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1.
Arch Microbiol ; 206(3): 102, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38353788

RESUMEN

A plant growth hormone indoleacetic acid-producing strain LX3-4T was isolated from a carrot rhizosphere soil sample collected in Shandong Province, China. It is Gram-stain-positive, non-motile, and has irregular short rod-shaped cells. LX3-4T shared high 16S rRNA gene sequence identity with Microbacterium oleivorans DSM 16091T (99.4%), M. testaceum NBRC 12675T (98.6%), M. marinum DSM 24947T (98.5%), M. resistens NBRC 103078T (98.4%), and M. paraoxydans NBRC 103076T (98.3%). Phylogenetic analysis based on the concatenated gene sequences of 16S rRNA gene, housekeeping genes gryB and rpoB also showed the distinction between strain LX3-4T and other Microbacterium species. Furthermore, analysis of the average nucleotide identities (ANI), the average amino acid identity (AAI), and the digital DNA-DNA hybridization (dDDH) values between strain LX3-4T and its relatives revealed that strain LX3-4T represents a distinct species. The genomic DNA G + C content of the strain is 69.5%. It can grow at 25-37 °C (optimum 37 °C), pH 5.0-10.0 (optimum pH 6.0-8.0), and the range of NaCl concentration is 0-7% (w/v) (optimum 1-5%). The colonies on agar plates are smooth, translucent, and pale yellow. The main cellular fatty acids of strain LX3-4T are anteiso-C15:0, anteiso-C17:0, and iso-C16:0. The predominant respiratory quinones are MK-12 and MK-11. Diphosphatidylglycerol, phosphatidylglycerol, an unidentified glycolipid, and an unidentified phosphoglycolipid are major polar lipids. The cell-wall sugar of strain LX3-4T is glucose. The cell-wall peptidoglycan contains glycine, alanine, lysine, and glutamic acid. In addition, this strain carries nitrogen fixation genes and can grow in nitrogen-free medium. Based on the polyphasic data, strain LX3-4T represents a novel species of the genus Microbacterium, for which the name Microbacterium dauci sp. nov. is proposed with strain LX3-4T (= CCTCC AB 2023103T = LMG 33159T) designated as the type strain.


Asunto(s)
Daucus carota , Hormona del Crecimiento , Reguladores del Crecimiento de las Plantas , Microbacterium , Filogenia , ARN Ribosómico 16S/genética , Rizosfera , Ácidos Indolacéticos , ADN
2.
Environ Sci Technol ; 58(35): 15650-15660, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39051472

RESUMEN

Accurate prediction of parameters related to the environmental exposure of chemicals is crucial for the sound management of chemicals. However, the lack of large data sets for training models may result in poor prediction accuracy and robustness. Herein, integrated transfer learning (TL) and multitask learning (MTL) was proposed for constructing a graph neural network (GNN) model (abbreviated as TL-MTL-GNN model) using n-octanol/water partition coefficients as a source domain. The TL-MTL-GNN model was trained to predict three bioaccumulation parameters based on enlarged data sets that cover 2496 compounds with at least one bioaccumulation parameter. Results show that the TL-MTL-GNN model outperformed single-task GNN models with and without the TL, as well as conventional machine learning models trained with molecular descriptors or fingerprints. Applicability domains were characterized by a state-of-the-art structure-activity landscape-based (abbreviated as ADSAL) methodology. The TL-MTL-GNN model coupled with the optimal ADSAL was employed to predict bioaccumulation parameters for around 60,000 chemicals, with more than 13,000 compounds identified as bioaccumulative chemicals. The high predictive accuracy and robustness of the TL-MTL-GNN model demonstrate the feasibility of integrating the TL and MTL strategy in modeling small-sized data sets. The strategy holds significant potential for addressing small data challenges in modeling environmental chemicals.


Asunto(s)
Aprendizaje Automático , Redes Neurales de la Computación , Bioacumulación
3.
Biochem Genet ; 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37658254

RESUMEN

Metabolites are important indicators of cancer and mutations in genes involved in amino acid metabolism may influence tumorigenesis. Immunotherapy is an effective cancer treatment option; however, its relationship with amino acid metabolism has not been reported. In this study, RNA-seq data for 371 liver cancer patients were acquired from TCGA and used as the training set. Data for 231 liver cancer patients were obtained from ICGC and used as the validation set to establish a gene signature for predicting liver cancer overall survival outcomes and immunotherapeutic responses. Four reliable groups based on 132 amino acid metabolism-related DEGs were obtained by consistent clustering of 371 HCC patients and a four-gene signature for prediction of liver cancer survival outcomes was developed. Our data show that in different clinical groups, the overall survival outcomes in the high-risk group were markedly low relative to the low-risk group. Univariate and multivariate analyses revealed that the characteristics of the 4-gene signature were independent prognostic factors for liver cancer. The ROC curve revealed that the risk characteristic is an efficient predictor for 1-, 2-, and 3-year HCC survival outcomes. The GSVA and KEGG pathway analyses revealed that high-risk score tumors were associated with all aspects of the degree of malignancy in liver cancer. There were more mutant genes and greater immune infiltrations in the high-risk groups. Assessment of the three immunotherapeutic cohorts established that low-risk score patients significantly benefited from immunotherapy. Then, we established a prognostic nomogram based on the TCGA cohort. In conclusion, the 4-gene signature is a reliable diagnostic marker and predictor for immunotherapeutic efficacy.

4.
J Environ Sci (China) ; 124: 98-104, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36182199

RESUMEN

Predicting the logarithm of hexadecane/air partition coefficient (L) for organic compounds is crucial for understanding the environmental behavior and fate of organic compounds and developing prediction models with polyparameter linear free energy relationships. Herein, two quantitative structure activity relationship (QSAR) models were developed with 1272 L values for the organic compounds by using multiple linear regression (MLR) and support vector machine (SVM) algorithms. On the basis of the OECD principles, the goodness of fit, robustness and predictive ability for the developed models were evaluated. The SVM model was first developed, and the predictive capability for the SVM model is slightly better than that for the MLR model. The applicability domain (AD) of these two models has been extended to include more kinds of emerging pollutants, i.e., oraganosilicon compounds. The developed QSAR models can be used for predicting L values of various organic compounds. The van der Waals interactions between the organic compound and the hexadecane have a significant effect on the L value of the compound. These in silico models developed in current study can provide an alternative to experimental method for high-throughput obtaining L values of organic compounds.


Asunto(s)
Contaminantes Ambientales , Relación Estructura-Actividad Cuantitativa , Alcanos , Modelos Lineales , Compuestos Orgánicos/química , Agua/química
5.
Curr Microbiol ; 79(8): 231, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35767195

RESUMEN

A novel facultatively aerobic bacterium designated SY8 was isolated from a peanut rhizosphere soil sample collected in Jiangsu Province, China. Cells are Gram-stain-positive, rod-shaped, and agar colonies are creamy, opaque, and usually rhizoidal. Strain growth occurs at 30 - 45 °C (optimum 30 °C), pH 4.0 - 10.0 (optimum pH 6.0) and 0 - 4% (w/v) NaCl (optimum 2%) in Luria-Bertani medium. Phylogenetic analysis of the 16S rRNA gene sequences indicated that strain SY8 forms a distinct lineage in the clade of genus Bacillus and is related to Bacillus pseudomycoides DSM 12442 T (99.9%). Phylogenetic analysis of the concatenated gene sequences of 16S rRNA, gryB and rpoD also indicated that strain SY8 forms a distinct lineage in Bacillus. Calculation of the average nucleotide identities and the digital DNA-DNA hybridization values between strain SY8 and the related type Bacillus strains further revealed that strain SY8 represents a distinct species. The predominant cellular fatty acids are iso C15:0 (28.7%) and summed feature 3 (C16:1ω7c and/or C16:1ω6c) (10.3%). The major polar lipids consisted of diphosphatidyl glycerol, phosphatidyl glycerol, phosphatidyl ethanolamine, phosphatidylinositol, and three unidentified phospholipids. The major menaquinone of SY8 was MK-7. Based on phenotypic, phylogenetic, chemotaxonomic, and genomic features, strain SY8 represents a novel species of the genus Bacillus. The name Bacillus arachidis sp. nov. is proposed with strain SY8T (= CCTCC AB 2021100 T=LMG 32409 T) designated as the type strain.


Asunto(s)
Bacillus , Fabaceae , Arachis , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Fabaceae/genética , Ácidos Grasos , Fosfatidilgliceroles , Filogenia , ARN Ribosómico 16S/genética , Rizosfera , Análisis de Secuencia de ADN , Suelo , Microbiología del Suelo
6.
Curr Microbiol ; 78(1): 397-402, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33136204

RESUMEN

A novel aerobic bacterium designated DX6T was isolated from a Gobi soil sample collected in Bachu County, China. Cells are Gram-stain-negative and rod-shaped and colonies are creamy, circular and smooth. The growth range of NaCl concentration was 1-15% (optimum 2-10%, w/v). Growth occurs at 10-45 °C (optimum 37 °C) and pH 5.0-10.0 (optimum pH 7.0-9.0). Phylogenetic analysis of the 16S rRNA gene sequences indicated that strain DX6T formed a distinct lineage in the clade of genus Halomonas and is related to Halomonas desiderata DSM 9502T (98.3%), Halomonas kenyensis AIR-2T (97.7%), Halomonas daqingensis DQD2-30T (97.6%), Halomonas saliphila LCB169T (97.4%) and Halomonas endophytica MC28T (96.2%). Analysis of the housekeeping genes gryB and rpoD and calculation of the average nucleotide identities and the digital DNA-DNA hybridization values between strain DX6T and the related type Halomonas strains further revealed that strain DX6T represented a distinct species. The main respiratory quinones of strain DX6T were ubiquinone 9 (Q-9) and ubiquinone 8 (Q-8). The predominant cellular fatty acids were summed feature 8 (C18:1ω7c and/or C18:1ω6c), summed feature 3 (C16:1ω7c and/or C16:1ω6c) and C16:0. The major polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, an unidentified phosphatidylglycolipid, and four unidentified lipids. Based on the phenotypic, phylogenetic, chemotaxonomic and genomic features, strain DX6T represents a novel species of the genus Halomonas. The name Halomonas bachuensis sp. nov. is proposed with strain DX6T (= CCTCC AB 2020094T = KCTC 82196T) designated as the type strain.


Asunto(s)
Halomonas , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos , Halomonas/genética , Fosfolípidos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Suelo
7.
Int J Syst Evol Microbiol ; 70(1): 364-372, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31661054

RESUMEN

A Gram-stain-negative, rod-shaped bacterium, motile by means of a single polar flagellum, designated S-6-2T, was isolated from petroleum polluted river sediment in Huangdao, Shandong Province, PR China. The 16S rRNA gene sequence analysis revealed that S-6-2T represented a member of the genus Pseudomonas, sharing the highest sequence similarities with Pseudomonas parafulva (97.5 %) and Pseudomonas fulva (97.5 %). Phylogenetic analysis based on 16S rRNA gene, concatenated 16S rRNA, gyrB, rpoB and rpoD genes and genome core-genes indicated that S-6-2T was affiliated with the members of the Pseudomonas pertucinogena group. The average nucleotide identity (ANI) and genome-to-genome distance between the whole genome sequences of S-6-2T and closely related species of the genus Pseudomonas within the P. pertucinogena group were less than 77.94 % and 20.5 %, respectively. Differences in phenotypic characteristics were also found between S-6-2T and the closely related species. The major cellular fatty acids (>10 %) were summed feature 8 (C18 : 1ω7c/ C18  : 1ω6c), C16 : 0, C17 : 0cyclo and C12 : 0. The predominant respiratory quinone was ubiquinone 9. The major polar lipids were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), one unidentified lipid (L1), two unidentified phospholipids (PL1 and PL2) and an aminophospholipid (APL). The DNA G+C content of the genome of S-6-2T was 60.1 mol%. On the basis of the evidence from the polyphasic taxonomic study, strain S-6-2T can be classified as representative of a novel species of the genus Pseudomonas, for which the name Pseudomonas phragmitis sp. nov. is proposed. The type strain is S-6-2T (=CGMCC 1.15798T=KCTC 52539T).


Asunto(s)
Sedimentos Geológicos/microbiología , Contaminación por Petróleo , Filogenia , Pseudomonas/clasificación , Ríos/microbiología , Contaminantes Químicos del Agua , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Hibridación de Ácido Nucleico , Petróleo , Fosfolípidos/química , Pseudomonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/química
8.
Prep Biochem Biotechnol ; 50(2): 116-122, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31526107

RESUMEN

In recent years, there have been many studies on producing acetoin by microbial fermentation, while only a few studies have focused on chiral acetoin biosynthesis. The weight assignment method was first applied to balance the chiral purity (expressed as the enantiomeric excess value) and the titer of acetoin. Bacillus sp. H-18W, a thermophile, was selected from seven Bacillus strains for chiral acetoin production. To lower the cost of the fermentation medium, soybean meal was used as a feedstock. Four kinds of frequently used commercial proteinases with different active sites were tested for the hydrolyzation of the soybean meal, and the combination of the acidic proteinase and the neutral proteinase showed the best results. In a fermentation medium containing 100 g L-1 glucose and 200 g L-1 hydrolysate, Bacillus sp. H-18W produced 21.84 g L-1 acetoin with an ee value of 96.25% at 60 h. This is the first report of using a thermophilic strain to produce chiral acetoin by microbial fermentation. Thermophilic fermentation can reduce the risk of bacterial contamination and can save cooling water. Using soybean meal hydrolysate and glucose as feedstocks, this work provides an economical and alternative method for the production of chiral pure acetoin.


Asunto(s)
Acetoína/metabolismo , Bacillus/metabolismo , Fermentación , Bacillus/clasificación , Cinética , Filogenia , Glycine max/metabolismo , Estereoisomerismo
9.
Prep Biochem Biotechnol ; 50(9): 935-942, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32538266

RESUMEN

2,3,5,6-Tetramethylpyrazine (TMP) has health care functions, especially for cardiovascular and cerebrovascular health. In this study, we found that Bacillus coagulans, a well-known probiotic, has the capability to produce acetoin, a precursor of TMP. The culture conditions and medium for the production of TMP by B. coagulans CICC 20138 were optimized. Then, a novel three-step process was successfully performed for the production of TMP from edible materials by B. coagulans. First, in the acetoin enrichment process, 12.61 ± 0.34 g/L acetoin was generated at 36 h. Second, in the spore enrichment process, various factors were optimized to make the bacteria produce more spores to improve the resistance to subsequent high-temperature reactions. Third, in the TMP enrichment process, the final concentration of TMP and B. coagulans spores contained in the product reached 2.54 ± 0.26 g/L and 8.81 × 108 CFU/mL at 46 h, respectively. This is the first report of using a probiotic bacterium to produce TMP. Using edible materials and the probiotic strain, this work provides a novel method for the production of a TMP food additive rich in B. coagulans spores.


Asunto(s)
Bacillus coagulans/metabolismo , Microbiología Industrial , Pirazinas/metabolismo , Acetoína/metabolismo , Probióticos/metabolismo
10.
Biotechnol Lett ; 37(8): 1671-7, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25851952

RESUMEN

OBJECTIVE: To enzymatically synthesize aroma acetoin fatty acid esters, useful as flavor and fragrance ingredients in foods. RESULTS: Immobilized Candida antarctica lipase B (CALB), performed significantly better than lipases from Rhizopus niveus and Candida rugosa in carrying out the esterification of acetoin and fatty acids. C4-C12 straight chain fatty acids were suitable acyl donors and CALB had a strong preference for longer straight chains up to ten carbon atoms. Higher temperatures, 40-60 °C, and higher acetoin/fatty acid molar ratios favored the conversion. The maximum yield of acetoin octanoate obtained was (51 ± 1) % after 24 h reaction time in hexane with 0.25 M octanoic acid, 5:1 excess acetoin and an enzyme concentration of 6 g/mol fatty acid at 60 °C. The enzyme activity declined at a steady rate during reuse at 60 °C and after the 10th cycle, 65 % of initial activity was still be retained. CONCLUSION: This is the first report of acetoin fatty acid ester synthesis by biological method and CALB has been shown to be effective for the lipase-catalyzed esterification of acetion and C4-C12 straight chain fatty acids.


Asunto(s)
Acetoína/metabolismo , Enzimas Inmovilizadas/metabolismo , Ácidos Grasos/metabolismo , Aromatizantes/metabolismo , Proteínas Fúngicas/metabolismo , Lipasa/metabolismo , Temperatura
11.
J Basic Microbiol ; 55(9): 1125-33, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25832555

RESUMEN

Polyhydroxyalkanoates (PHAs) are usually biosynthesized using mesophilic strains, but the fermentation processes often suffer from bacterial contamination. This work reports the screening of thermophilic bacteria capable of producing PHAs under elevated temperatures to reduce the contamination risk. Strain XH2 was isolated from an oilfield and identified as Aneurinibacillus sp. by morphology, physiological-biochemical characterization, and 16S rDNA phylogenetic analysis. This strain can produce PHA granules, which was detected by Nile red staining and transmission electron microscopic imaging. At 55 °C, 111.6 mg l(-1) of PHA was produced in a fermentation medium containing glucose, peptone, and yeast extract. If peptone was removed from the medium, the yield of PHA would be enhanced by 2.4 times. The main monomers of the PHA product were identified to be 3-hydroxybutyrate and 3-hydroxyvalerate with a molar ratio of 17.2:1 by gas chromatography-mass spectroscopy (GC-MS) and nuclear magnetic resonance analyses. Two minor homologues, 3-hydroxyoctanoate, and 3-hydroxy-4-phenylbutanoate, were tentatively identified by GC-MS as well. This is the first report of thermophilic PHA bacterial producer from the Firmicutes phylum.


Asunto(s)
Fermentación , Yacimiento de Petróleo y Gas/microbiología , Paenibacillus/metabolismo , Polihidroxialcanoatos/biosíntesis , China , Cromatografía de Gases , Espectrometría de Masas , Microscopía Electrónica , Yacimiento de Petróleo y Gas/química , Paenibacillus/química , Paenibacillus/clasificación , Paenibacillus/aislamiento & purificación , Filogenia , Polihidroxialcanoatos/química
12.
Noncoding RNA Res ; 9(3): 744-758, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38577019

RESUMEN

Trastuzumab-induced cardiotoxicity (TIC) is a common and serious disease with abnormal cardiac function. Accumulating evidence has indicated certain non-coding RNAs (ncRNAs), functioning as competing endogenous RNAs (ceRNAs), impacting the progression of cardiovascular diseases. Nonetheless, the specific involvement of ncRNA-mediated ceRNA regulatory mechanisms in TIC remains elusive. The present research aims to comprehensively investigate changes in the expressions of all ncRNA using whole-transcriptome RNA sequencing. The sequencing analysis unveiled significant dysregulation, identifying a total of 43 circular RNAs (circRNAs), 270 long noncoding RNAs (lncRNAs), 12 microRNAs (miRNAs), and 4131 mRNAs in trastuzumab-treated mouse hearts. Subsequently, circRNA-based ceRNA networks consisting of 82 nodes and 91 edges, as well as lncRNA-based ceRNA networks comprising 111 nodes and 112 edges, were constructed. Using the CytoNCA plugin, pivotal genes-miR-31-5p and miR-644-5p-were identified within these networks, exhibiting potential relevance in TIC treatment. Additionally, KEGG and GO analyses were conducted to explore the functional pathways associated with the genes within the ceRNA networks. The outcomes of the predicted ceRNAs and bioinformatics analyses elucidated the plausible involvement of ncRNAs in TIC pathogenesis. This insight contributes to a better understanding of underlying mechanisms and aids in identifying promising targets for effective prevention and treatment strategies.

13.
J Hazard Mater ; 469: 134096, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38522195

RESUMEN

Arsenic (As)-contaminated soil poses great health risk to human mostly through inadvertent oral exposure. We investigated CaAl-layered double hydroxide (CaAl-LDH), a promising immobilising agent, for the remediation of As-contaminated Chinese soils. The effects on specific soil properties and As fractionation were analyzed, and changes in the health risk of soil As were accurately assessed by means of advanced in vivo mice model and in vitro PBET-SHIME model. Results showed that the application of CaAl-LDH significantly increased soil pH and concentration of Fe and Al oxides, and effectively converted active As fractions into the most stable residual fraction, guaranteeing long-term remediation stability. Based on in vivo test, As relative bioavailability was significantly reduced by 37.75%. Based on in vitro test, As bioaccessibility in small intestinal and colon phases was significantly reduced by 25.65% and 28.57%, respectively. Furthermore, As metabolism (reduction and methylation) by the gut microbiota inhabiting colon was clearly observed. After immobilisation with CaAl-LDH, the concentration of bioaccessible As(Ⅴ) in the colon fluid was significantly reduced by 61.91%, and organic As (least toxic MMA(V) and DMA(V)) became the main species, which further reduced the health risk of soil As. In summary, CaAl-LDH proved to be a feasible option for immobilisation remediation of As-contaminated soils, and considerable progress was made in relevant health risk assessment.


Asunto(s)
Arsénico , Contaminantes del Suelo , Animales , Humanos , Ratones , Arsénico/química , Disponibilidad Biológica , Contaminantes del Suelo/análisis , Suelo/química , Medición de Riesgo
14.
Environ Sci Pollut Res Int ; 30(50): 108846-108854, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37759049

RESUMEN

With an increase in production and application of various engineering nanomaterials (ENMs), they will inevitably be released into the environment. Adsorption of various organic chemicals onto ENMs will impact on their environmental behavior and toxicology. It is unrealistic to experimentally determine adsorption equilibrium constants (K) for the vast number of organics and ENMs due to high cost in expenditure and time. Herein, appropriate molecular dynamics (MD) methods were evaluated and selected by comparing experimental K values of seven organics adsorbed onto graphene with the MD-calculated ones. Machine learning (ML) models on K of organics adsorption onto graphene and black phosphorus nanomaterials were constructed based on a benchmark data set from the MD simulations. Lasso models based on Mordred descriptors outperformed ML models built by support vector machine, random forest, k-nearest neighbor, and gradient boosting decision tree, in terms of cross-validation coefficients (Q2 > 0.90). The Lasso models also outperformed conventional poly-parameter linear free energy relationship models for predicting logK. Compared with previous models, the Lasso models considered more compounds with different functional groups and thus have broader applicability domains. This study provides a promising way to fill the data gap in logK for chemicals adsorbed onto the ENMs.


Asunto(s)
Grafito , Simulación de Dinámica Molecular , Adsorción , Compuestos Orgánicos/química , Aprendizaje Automático
15.
Water Res ; 244: 120506, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37651863

RESUMEN

Fe(VI) is a versatile agent for water purification, and various strategies have been developed to improve its pollutant removal efficiency. Herein, it was found that in addition to intermediate iron species [Fe(IV)/Fe(V)], direct electron transfer (DET) played a significant role in the abatement of organic pollutants in Fe(VI)/carbon quantum dots (CQDs) system. Around 86, 83, 73, 64, 52, 45 and 17% of BPA, DCF, SMX, 4-CP, phenol, p-HBA, and IBP (6 µM) could be oxidized by 30 µM of Fe(VI), whereas with the addition of CQDs (4 mg/L), the oxidation ratio of these pollutants increased to 98, 99, 80, 88, 87, 66 and 57%, respectively. The negative impact induced by solution pH and background constituents on Fe(VI) abatement of pollutants could be alleviated by CQDs, and CQDs acted as catalysts for mediating DET from organic pollutants to Fe(VI). Theoretical calculation revealed that iron species [Fe(VI)/Fe(V)/Fe(IV)] was responsible for the oxidation of 36% of phenol, while DET contributed to the oxidation of 64% of phenol in the Fe(VI)/CQDs system. Compared with iron species oxidation, the CQDs mediated DET from pollutants to Fe(VI) was more efficient for utilizing the oxidation capacity of Fe(VI). The DET mechanism presented in the study provides a prospective strategy for improving the pollution control potential of Fe(VI).


Asunto(s)
Contaminantes Ambientales , Electrones , Fenol , Fenoles , Carbono , Hierro
16.
J Colloid Interface Sci ; 629(Pt B): 336-344, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36162391

RESUMEN

Titanium dioxide photocatalysts with high reduction potential and visible light response hold great promise in photochemical conversion. Here, we used a simple glycine doping method to synthesize novel N-TiO2@C photocatalysts with upward shifted conduction bands and narrowed band gaps as well as inhibited recombination of photoinduced electron-hole pairs. The N-TiO2@C photocatalysts exhibited higher visible light response and remarkably enhanced photocatalytic activity in the production of nicotinamide adenine dinucleotide (NADH) by photomediated reduction of NAD+ without any electron mediator. The yield of NADH was up to 70.3 % far greater than that of the undoped TiO2 (11.3 %), and it stabilized at ca. 60 % after 10 cycles. The viability of coupling NADH regeneration with enzymatic reaction (alcohol dehydrogenase) was established in aldehyde reduction where formaldehyde was specifically reduced to methanol. These findings shed new light on the modulation of the band structure of semiconductors and develop an electron mediator free strategy for NADH-dependent artificial photosynthesis through coupled photocatalytic and enzymatic approaches.

17.
Front Cell Infect Microbiol ; 12: 808837, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35281446

RESUMEN

Objectives: Doxorubicin (Dox), a chemotherapeutic anthracycline agent for the treatment of a variety of malignancies, has a limitation in clinical application for dose-dependent cardiotoxicity. The purpose of this study was to explore the relationship between the composition/function of the gut microbiota and Dox-induced cardiotoxicity (DIC). Methods: C57BL/6J mice were injected intraperitoneally with 15 mg/kg of Dox, with or without antibiotics (Abs) administration. The M-mode echocardiograms were performed to assess cardiac function. The histopathological analysis was conducted by H&E staining and TUNEL kit assay. The serum levels of creatine kinase (CK), CK-MB (CK-MB), lactic dehydrogenase (LDH), and cardiac troponin T (cTnT) were analyzed by an automatic biochemical analyzer. 16S rRNA gene and metagenomic sequencing of fecal samples were used to explore the gut microbiota composition and function. Key Findings: Dox caused left ventricular (LV) dilation and reduced LV contractility. The levels of cardiomyocyte apoptosis and myocardial enzymes were elevated in Dox-treated mice compared with the control (Con) group. 16S rRNA gene sequencing results revealed significant differences in microbial composition between the two groups. In the Dox group, the relative abundances of Allobaculum, Muribaculum, and Lachnoclostridium were significantly decreased, whereas Faecalibaculum, Dubosiella, and Lachnospiraceae were significantly increased compared with the Con group at the genus level. Functional enrichment with Cluster of orthologous groups of proteins (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that the Dox mice displayed different clusters of cellular processes and metabolism from the Con mice. The different species and their functions between the two groups were associated with the clinical factors of cardiac enzymes. Moreover, depletion of the gut microbiota could alleviate Dox-induced myocardial injury and cardiomyocyte apoptosis. Conclusions: The study here shows that composition imbalance and functional changes of the gut microbiota can be one of the etiological mechanisms underlying DIC. The gut microbiota may serve as new targets for the treatment of cardiotoxicity and cardiovascular diseases.


Asunto(s)
Cardiotoxicidad , Microbioma Gastrointestinal , Animales , Apoptosis , Cardiotoxicidad/tratamiento farmacológico , Cardiotoxicidad/etiología , Cardiotoxicidad/metabolismo , Doxorrubicina/toxicidad , Ratones , Ratones Endogámicos C57BL , Estrés Oxidativo , ARN Ribosómico 16S/genética
18.
Nanomaterials (Basel) ; 12(4)2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35214919

RESUMEN

Layered black phosphorus (BP) has exhibited exciting application prospects in diverse fields. Adsorption of organics onto BP may influence environmental behavior and toxicities of both organic pollutants and BP nanomaterials. However, contributions of various intermolecular interactions to the adsorption remain unclear, and values of adsorption parameters such as adsorption energies (Ead) and adsorption equilibrium constants (K) are lacking. Herein, molecular dynamic (MD) and density functional theory (DFT) was adopted to calculate Ead and K values. The calculated Ead and K values for organics adsorbed onto graphene were compared with experimental ones, so as to confirm the reliability of the calculation methods. Polyparameter linear free energy relationship (pp-LFER) models on Ead and logK were developed to estimate contributions of different intermolecular interactions to the adsorption. The adsorption in the gaseous phase was found to be more favorable than in the aqueous phase, as the adsorbates need to overcome cohesive energies of water molecules onto BP. The affinity of the aromatics to BP was comparable to that of graphene. The pp-LFER models performed well for predicting the Ead and K values, with external explained variance ranging from 0.90 to 0.97, and can serve as effective tools to rank adsorption capacities of organics onto BP.

19.
Int Immunopharmacol ; 105: 108545, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35091339

RESUMEN

Sepsis-induced cardiac injury leads to the high rate of mortality, the therapeutics for this disorder are limited. Disulfiram (DSF) is an FDA-approved treatment for chronic alcohol addiction, and its cardio-protection is gradually discovered in recent years. In present study, mice were injected with lipopolysaccharide (LPS, 15 mg/kg) to induce a septic cardiac injury model, and aimed to investigate the protective effect of DSF on sepsis-induced cardiac injury and the underlying mechanisms. Results showed that DSF treatment alleviated the lowered left heart function and myocardial cell apoptosis induced by LPS. Moreover, we found that LPS increased myocardium lipid peroxidation, DNA damage and the activation of NLRP3 inflammasome, which were significantly reduced by DSF. These results suggested the protective role of DSF in LPS-induced cardiac injury, and the mechanism involved the inhibition on the oxidative stress and NLRP3 inflammasome activation. Given the potent cardiac protection effect of DSF, repurposing DSF in the clinic would represent a new strategy to protect and treat sepsis-induced cardiac injury.


Asunto(s)
Inflamasomas , Lipopolisacáridos , Animales , Disulfiram/farmacología , Disulfiram/uso terapéutico , Inflamasomas/metabolismo , Ratones , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Estrés Oxidativo
20.
J Pharm Pharmacol ; 74(2): 259-267, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34923585

RESUMEN

OBJECTIVES: Disulfiram (DSF), an old drug for treating chronic alcohol addiction, has been reported to exhibit widely pharmacological actions. This study aimed to explore the protective effect of DSF on lipopolysaccharide (LPS)-induced acute kidney injury (AKI). METHODS: C57BL/6J mice were treated with 15 mg/kg LPS (i.p.) with or without DSF pre-treatment (i.p.). The histopathological analysis was conducted by H&E staining and TUNEL kit assay. An automatic biochemical analyser was used to determine the serum creatinine and blood urea nitrogen (BUN). Expressions of 8-OHdG, NLRP3 and IL-1ß in the kidney tissues were observed by IHC staining. The protein expressions of ß-actin, Bax, Bcl-2, NLRP3, caspase-1 (p20), pro-IL-1ß and IL-1ß were analysed by western blot. KEY FINDINGS: DSF attenuated the histopathologic deterioration of the kidney and inhibited the elevation of creatinine and BUN levels in mice. DSF inhibited LPS-induced cell apoptosis. Moreover, DSF treatment reversed the LPS-induced excessive oxidative stress. The NLRP3 inflammasome activation induced by the LPS, as indicated by up-regulation of NLRP3 expression, cleaved caspase-1 (p20) and IL-1ß, was also suppressed by DSF. CONCLUSIONS: The study here shows that DSF protects against the AKI induced by LPS at least partially via inhibiting oxidative stress and NLRP3 inflammasome activation.


Asunto(s)
Lesión Renal Aguda/tratamiento farmacológico , Disulfiram/farmacología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Estrés Oxidativo/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Modelos Animales de Enfermedad , Etiquetado Corte-Fin in Situ , Inflamasomas/metabolismo , Lipopolisacáridos , Masculino , Ratones , Ratones Endogámicos C57BL
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