Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 246
Filtrar
1.
BMC Med ; 22(1): 407, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304842

RESUMO

BACKGROUND: Kidney transplantation is the optimal renal replacement therapy for children with end-stage renal disease; however, delayed graft function (DGF), a common post-operative complication, may negatively impact the long-term outcomes of both the graft and the pediatric recipient. However, there is limited research on DGF in pediatric kidney transplant recipients. This study aims to develop a predictive model for the risk of DGF occurrence after pediatric kidney transplantation by integrating donor and recipient characteristics and utilizing machine learning algorithms, ultimately providing guidance for clinical decision-making. METHODS: This single-center retrospective cohort study includes all recipients under 18 years of age who underwent single-donor kidney transplantation at our hospital between 2016 and 2023, along with their corresponding donors. Demographic, clinical, and laboratory examination data were collected from both donors and recipients. Univariate logistic regression models and differential analysis were employed to identify features associated with DGF. Subsequently, a risk score for predicting DGF occurrence (DGF-RS) was constructed based on machine learning combinations. Model performance was evaluated using the receiver operating characteristic curves, decision curve analysis (DCA), and other methods. RESULTS: The study included a total of 140 pediatric kidney transplant recipients, among whom 37 (26.4%) developed DGF. Univariate analysis revealed that high-density lipoprotein cholesterol (HDLC), donor after circulatory death (DCD), warm ischemia time (WIT), cold ischemia time (CIT), gender match, and donor creatinine were significantly associated with DGF (P < 0.05). Based on these six features, the random forest model (mtry = 5, 75%p) exhibited the best predictive performance among 97 machine learning models, with the area under the curve values reaching 0.983, 1, and 0.905 for the entire cohort, training set, and validation set, respectively. This model significantly outperformed single indicators. The DCA curve confirmed the clinical utility of this model. CONCLUSIONS: In this study, we developed a machine learning-based predictive model for DGF following pediatric kidney transplantation, termed DGF-RS, which integrates both donor and recipient characteristics. The model demonstrated excellent predictive accuracy and provides essential guidance for clinical decision-making. These findings contribute to our understanding of the pathogenesis of DGF.


Assuntos
Função Retardada do Enxerto , Transplante de Rim , Aprendizado de Máquina , Doadores de Tecidos , Humanos , Transplante de Rim/efeitos adversos , Feminino , Masculino , Criança , Estudos Retrospectivos , Adolescente , Pré-Escolar , Lactente
2.
Diabetes Obes Metab ; 26(1): 3-15, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37726973

RESUMO

Emerging evidence suggests that the ubiquitin-mediated degradation of insulin-signalling-related proteins may be involved in the development of insulin resistance and its related disorders. Tripartite motif-containing (TRIM) proteins, a superfamily belonging to the E3 ubiquitin ligases, are capable of controlling protein levels and function by ubiquitination, which is essential for the modulation of insulin sensitivity. Recent research has indicated that some of these TRIMs act as key regulatory factors of metabolic disorders such as type 2 diabetes mellitus, obesity, nonalcoholic fatty liver disease, and atherosclerosis. This review provides a comprehensive overview of the latest evidence linking TRIMs to the regulation of insulin resistance and its related disorders, their roles in regulating multiple signalling pathways or cellular processes, such as insulin signalling pathways, peroxisome proliferator-activated receptor signalling pathways, glucose and lipid metabolism, the inflammatory response, and cell cycle control, as well as recent advances in the development of TRIM-targeted drugs.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Insulinas , Humanos , Ubiquitinação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/metabolismo
3.
BMC Genomics ; 24(1): 588, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794356

RESUMO

BACKGROUND: The fruits of Gardenia are rich in flavonoids and geniposides, which have various pharmacological effects such as antioxidant, anti-inflammatory and anticancer. In this study, we analyzed the transcriptome and metabolome of gardenia peel and kernel at different growth stages, revealed the regulatory network related to flavonoid synthesis, and identified the key regulatory genes. RESULTS: The results showed that in terms of flavonoid metabolic pathways, gardenia fruits mainly synthesized cinnamic acid through the phenylpropanoid pathway, and then synthesized flavonoids through the action of catalytic enzymes such as 4-coumaroyl-CoA ligase, chalcone synthase, chalcone isomerase and flavanol synthase, respectively. In addition, we found that the metabolomics data showed a certain spatial and temporal pattern in the expression of genes related to the flavonoid metabolism pathway and the relative content of metabolites, which was related to the development and ripening process of the fruit. CONCLUSIONS: In summary, this study successfully screened out the key genes related to the biosynthesis metabolism of flavonoids in gardenia through the joint analysis of transcriptome and metabolome. This is of certain significance to the in-depth study of the formation mechanism of gardenia efficacy components and the improvement of quality.


Assuntos
Gardenia , Iridoides , Gardenia/genética , Frutas/genética , Flavonoides , Multiômica
4.
Small ; 19(17): e2207705, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36710245

RESUMO

Coupling hollow semiconductor with metal-organic frameworks (MOFs) holds great promise for constructing high-efficient CO2 photoreduction systems. However, energy band mismatch between them makes it difficult to exert their advantages to maximize the overall photocatalytic efficiency, since that the blockage of desirable interfacial charge transfer gives rise to the enrichment of photoelectrons and CO2 molecules on the different locations. Herein, an interfacial engineering is presented to overcome this impediment, based on the insertion of plasmonic metal into the heterointerfaces between them, forming a stacked semiconductor/metal@MOF photocatalyst. Experimental observations and theoretical simulations validate the critical roles of embedded Au in maneuvering the charge separation/transfer and surface reaction: (i) bridges the photoelectron transfer from hollow CdS (H-CdS) to ZIF-8; (ii) produces hot electrons and shifts them to ZIF-8; (iii) induces the formation of ZIF-8 defects in promoting the CO2 adsorption/activation and transformation to CO with low energy barriers. Consequently, the as-prepared H-CdS/Au@ZIF-8 with optimal ZIF-8 thickness exhibits distinctly boosted activity and superb selectivity in CO production as compared with H-CdS@ZIF-8 and other counterparts. This work provides protocols to take full advantages of components involved for enhanced solar-to-chemical energy conversion efficiency of hybrid artificial photosynthetic systems through rationally harnessing the charge transfer between them.

5.
Angew Chem Int Ed Engl ; 62(30): e202305639, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37254229

RESUMO

In photosynthesis, solar energy is harvested by photosensitizers, and then, the excited electrons transfer via a Z-Scheme mode to enzymatic catalytic centers to trigger redox reactions. Herein, we constructed a core-shell Z-scheme heterojunction of semiconductor@single-atom catalysts (SACs). The oxygen-vacancy-rich ZnO core and single-atom Co-N4 sites supported on nitrogen-rich carbon shell (SA-Co-CN) act as the photosensitizer and the enzyme-mimicking active centers, respectively. Driven by built-in electric field across the heterojunction, photoexcited electrons could rapidly (2 ps) transfer from the n-type ZnO core to the p-type SA-Co-CN shell, finally boosting the catalytic performance of the surface-exposed single-atom Co-N4 sites for peroxymonosulfate (PMS) activation under light irradiation. The synergies between photocatalysis and heterogeneous Fenton-like reaction lead to phenomenally enhanced production of various reactive oxygen species for rapid degradation of various microcontaminants in water. Experimental and theoretical results validate that the interfacial coupling of SA-Co-CN with ZnO greatly facilitates PMS adsorption and activation by reducing the adsorption energy and enhancing the cascade electron transfer processes for the photo-Fenton-like reaction.

6.
Plant Biotechnol J ; 20(2): 323-334, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34558775

RESUMO

Ramie is an important fibre-producing crop in China; however, the genetic basis of its agronomic traits remains poorly understood. We produced a comprehensive map of genomic variation in ramie based on resequencing of 301 landraces and cultivars. Genetic analysis produced 129 signals significantly associated with six fibre yield-related traits, and several genes were identified as candidate genes for respective traits. Furthermore, we found that natural variations in the promoter region of Bnt14G019616 were associated with extremely low fibre abundance, providing the first evidence for the role of pectin methylesterase in fibre growth of plants. Additionally, nucleotide diversity analysis revealed that breeding selection has been markedly focussed on chromosome 9 in which ~ 39.6% sequence underwent selection, where one gibberellin-signalling-repressed DELLA gene showed distinct selection signatures in the cultivars. This study provides insights into the genetic architecture and breeding history of fibre yield traits in ramie. Moreover, the identification of fibre yield-related genetic loci and large-scale genomic variation represent valuable resources for genomics-assisted breeding of this crop.


Assuntos
Boehmeria , Boehmeria/genética , Loci Gênicos , Genoma de Planta/genética , Estudo de Associação Genômica Ampla , Fenótipo , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único , Seleção Genética
7.
Ecotoxicol Environ Saf ; 233: 113313, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35182801

RESUMO

BACKGROUND: A few studies have reported phthalate exposure as a risk factor for depressive symptoms, but the results have been inconsistent. Whether chronic inflammation mediates the relationship between phthalates (PAEs) and depressive symptoms remains unclear. In this study, we establish mediating models of inflammatory factors and explore the mediating role of chronic inflammation in the association between PAEs exposure and depressive symptoms. METHODS: The sample included 989 participants from the Study on Health and Environment of the Elderly in Lu'an City, Anhui Province. Geriatric depression scale (GDS-30) was used to screen depressive symptoms of the elderly. The levels of seven kinds of PAEs in urine samples and four inflammatory factors in serum of the elderly were measured. To establish the mediating effect of inflammatory factors to explore the potential effect of PAEs exposure on the increased odds of depressive symptoms. RESULTS: Adjusted for multiple variables, the highest tertiles of Mono (2-ethylhexyl) phthalate (MEHP) (95%CI = 1.051-2.112), Mono benzyl phthalate (MBzP) (95%CI = 1.016-2.082) and Mono butyl phthalate (MBP) (95%CI = 1.102-2.262) were positively correlated with depressive symptoms. The mediating effect of IL-6 and generalized inflammation factor between MEHP exposure and depressive symptoms were 15.96% (95%CI=0.0288-0.1971) and 14.25% (95%CI = 0.0167-0.1899). CONCLUSIONS: High levels of MEHP, MBzP and MBP increased the odds of depressive symptoms in the elderly, and chronic inflammation had a partial mediating effect on the increased odds of depressive symptoms due to MEHP exposure.


Assuntos
Poluentes Ambientais , Ácidos Ftálicos , Idoso , Depressão/induzido quimicamente , Dibutilftalato , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidade , Poluentes Ambientais/urina , Humanos , Inflamação/induzido quimicamente , Ácidos Ftálicos/toxicidade , Ácidos Ftálicos/urina
8.
Small ; 17(45): e2102105, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34558184

RESUMO

Rational phase engineering of reduction cocatalyst offers a promising route to modulate the photocatalytic activity and selectivity in the conversion of CO2 to chemical feedstocks. However, it remains a great challenge to choose a suitable phase given that high-crystallinity phase is more conducive to the charge transfer and separation, while amorphous phase is more favorable for the adsorption and activation of CO2 molecules. To resolve this dilemma, herein, with Pd as a well-defined model, a surface amorphization strategy has been developed to fabricate crystalline@amorphous semi-core-shell cocatalysts based on the transformation of outer layer atoms of crystalline cocatalysts to disorder phase. According to the theoretical and experimental analysis, in the heterostructured cocatalysts, crystalline core shuttles the photoexcited electrons from light-harvesting semiconductor to amorphous shell due to its strong electronic coupling with both components. Meanwhile, amorphous shell provides efficient active sites for preferential activation and conversion of CO2 and suppression of undesirable proton reduction. Benefiting from the synergistic effects between crystalline core and amorphous shell, the optimized heterophase cocatalyst with suitable thickness of amorphous shell achieves superior CO (22.2 µmol gcat-1 h-1 ) and CH4 (38.1 µmol gcat-1 h-1 ) formation rates with considerable selectivity and high stability in comparison with crystalline and amorphous counterparts.


Assuntos
Dióxido de Carbono , Procedimentos de Cirurgia Plástica , Eletrônica , Elétrons , Semicondutores
9.
Appl Environ Microbiol ; 87(18): e0111021, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34232723

RESUMO

Microbial degradation plays an important role in environmental remediation. However, most microorganisms' pollutant-degrading capabilities are weakened due to their entry into a viable but nonculturable (VBNC) state. Although there is some evidence for the VBNC state of pollutant-degrading bacteria, limited studies have been conducted to investigate the VBNC state of pollutant degraders among fungi. In this work, the morphological, physiological, and molecular changes of phenol-degrading yeast strain LN1 exposed to high phenol concentrations were investigated. The results confirmed that Candida sp. strain LN1, which possessed a highly efficient capability of degrading 1,000 mg/liter of phenol as well as a high potential for aromatic compound degradation, entered into the VBNC state after 14 h of incubation with 6,000 mg/liter phenol. Resuscitation of VBNC cells can restore their phenol degradation performance. Compared to normal cells, significant dwarfing, surface damage, and physiological changes of VBNC cells were observed. Molecular analysis indicated that downregulated genes were related to the oxidative stress response, xenobiotic degradation, and carbohydrate and energy metabolism, whereas upregulated genes were related to RNA polymerase, amino acid metabolism, and DNA replication and repair. This report revealed that a pollutant-degrading yeast strain entered into the VBNC state under high concentrations of contaminants, providing new insights into its survival status and bioremediation potential under stress. IMPORTANCE The viable but nonculturable (VBNC) state is known to affect the culturability and activity of microorganisms. However, limited studies have been conducted to investigate the VBNC state of other pollutant degraders, such as fungi. In this study, the VBNC state of a phenol-degrading yeast strain was discovered. In addition, comprehensive analyses of the morphological, physiological, and molecular changes of VBNC cells were performed. This study provides new insight into the VBNC state of pollutant degraders and how they restored the activities that were inhibited under stressful conditions. Enhanced bioremediation performance of indigenous microorganisms could be expected by preventing and controlling the formation of the VBNC state.


Assuntos
Candida/efeitos dos fármacos , Poluentes Ambientais/administração & dosagem , Fenol/administração & dosagem , Biodegradação Ambiental/efeitos dos fármacos , Candida/genética , Candida/crescimento & desenvolvimento , Candida/metabolismo , Relação Dose-Resposta a Droga , Genoma Fúngico , Viabilidade Microbiana/efeitos dos fármacos , Estresse Fisiológico , Sequenciamento Completo do Genoma
10.
Ecotoxicol Environ Saf ; 211: 111889, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33461014

RESUMO

The widespread use of cyclophosphamide (CP) in medical treatment had caused ubiquitous contamination in the environment. To data, many studies have been carried out on the toxic effect of CP. However, among these toxic effects of CP, which are the most sensitive remains unclear. Present study aimed to investigate the toxicity of CP on mice and evaluate the sensitivity of physiological-biochemical parameters upon exposure of mice to CP. Results showed that as compared with the control group, CP caused significant reduction in body weight (p < 0.01), spleen coefficient (p < 0.01), leukocyte density (p < 0.01) and alanine transaminase (ALT) in kidney (p < 0.01); However superoxide dismutase (SOD), malondialdehyde (MDA), ALT in liver and creatinine (Cr) in kidney significantly (p < 0.05) increased. Among the suppressed physiological and biochemical parameters, the sensitivity to CP toxicity was generally ranked as body weight > leukocyte density > ALT in kidney > spleen coefficient; while among the stimulated parameters, the sensitivity was ranked as MDA (liver) > Cr (kidney) > ALT (liver). Overall, the most sensitive parameters to CP toxicity may be associated with growth, immune system and the normal function of liver and kidney.


Assuntos
Ciclofosfamida/toxicidade , Mutagênicos/toxicidade , Alanina Transaminase/metabolismo , Animais , Antioxidantes/metabolismo , Creatinina , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Camundongos , Estresse Oxidativo/fisiologia , Superóxido Dismutase/metabolismo , Testes de Toxicidade
11.
BMC Emerg Med ; 21(1): 52, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879092

RESUMO

BACKGROUND: Endothelial glycocalyx (EG) abnormal degradation were widely found in critical illness. However, data of EG degradation in multiple traumas is limited. We performed a study to assess the EG degradation and the correlation between the degradation and organ functions in polytrauma patients. METHODS: A prospective observational study was conducted to enroll health participants (control group) and polytrauma patients (trauma group) at a University affiliated hospital between Feb 2020 and Oct 2020. Syndecan1 (SDC1) and heparin sulfate (HS) were detected in serum sample of both groups. In trauma group, injury severity scores (ISS) and sequential organ failure assessments (SOFA) were calculated. Occurrences of acute kidney injury (AKI), trauma-induced coagulopathy (TIC) within 48 h and 28-day all-cause mortality in trauma group were recorded. Serum SDC1 and HS levels were compared between two groups. Correlations between SDC1/HS and the indicators of organ systems in the trauma group were analyzed. ROC analyses were performed to assess the predictive value of SDC1 and HS for AKI, TIC within 48 h, and 28-day mortality in trauma group. RESULTS: There were 45 polytrauma patients and 15 healthy participants were collected, totally. SDC1 and HS were significantly higher in trauma group than in control group (69.39 [54.18-130.80] vs. 24.15 [13.89-32.36], 38.92 [30.47-67.96] vs. 15.55 [11.89-23.24], P <  0.001, respectively). Trauma group was divided into high degradation group and low degradation group according to SDC1 median. High degradation group had more severe ISS, SOFA scores, worse organ functions (respiratory, kidney, coagulation and metabolic system), and higher incidence of hypothermia, acidosis and shock. The area under the receiver operator characteristic curves (AUC) of SDC1 to predict AKI, TIC occurrence within 48 h and 28-day mortality were 0.838 (95%CI: 0.720-0.957), 0.700 (95%CI: 0.514-0.885) and 0.764 (95%CI: 0.543-0.984), respectively. CONCLUSIONS: EG degradation was elevated significantly in polytrauma patients, and the degradation was correlated with impaired respiratory, kidney, coagulation and metabolic systems in early stage. Serum SDC1 is a valuable predictive indicator of early onset of AKI, TIC, and 28-day mortality in polytrauma patients.


Assuntos
Endotélio/patologia , Glicocálix , Traumatismo Múltiplo , Glicocálix/patologia , Humanos , Escala de Gravidade do Ferimento , Traumatismo Múltiplo/complicações , Escores de Disfunção Orgânica , Estudos Prospectivos , Curva ROC , Estudos Retrospectivos
12.
Nanotechnology ; 31(16): 165401, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-31860891

RESUMO

The development of low-cost, highly efficient and durable non-precious-metal (NPM) electrocatalysts for the oxygen reduction reaction (ORR) is of great significance. Herein, we report an ingenious two-step strategy for the fabrication of NPM electrocatalysts containing multifarious cobalt species embedded in nitrogen-rich nanocarbons (Co-N-C). Firstly, Co ions were fixed by coordination with 1H-Imidazo[4,5-f][1,10]phenanthroline (Hip), and secondly the Co-Hip precursor with abundant Co, C and N sources was subjected to calcination at various temperatures (700-900 °C). The obtained Co-N-C catalysts exhibited excellent activity in terms of the ORR in alkaline conditions, with a half-wave potential of 0.82 eV versus the reversible hydrogen electrode, which is close to that of commercial Pt/C. Moreover, the Co-N-C exhibited an unexpected catalytic activity with long-term stability and immunity to methanol which is better than commercial Pt/C catalyst, suggesting that Co-N-C with dual active sites of the single-atom Co sites (Co-N4) and Co2N can be a promising alternative to replace Pt-based electrocatalysts in fuel cells. This work can provide a new route to designing promising catalysts with dual active sites for ORR.

13.
Mol Biol Rep ; 47(2): 1013-1020, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31820312

RESUMO

Ramie (Boehmeria nivea) is a widely cropped species in southern China due to its high economic value of natural fiber for industry. Development of phloem and xylem is key evidence for generating fiber. However, the MicroRNA (miRNA) profiles of phloem and xylem in ramie have not been reported yet. miRNA belong to a small RNA family which has been recognized as an important regulator for various biological processes. In the present study, we aimed to identify differently expressed miRNAs between phloem and xylem in adult ramie. The results showed that 137 and 122 unique conserved miRNAs were identified from phloem and xylem libraries, respectively. Meanwhile, 4 novel miRNAs were identified from ramie by miRDeep2. Of these miRNAs, 77 conserved miRNAs in ramie were differentially expressed. Among the differentially expressed miRNAs, 44 miRNAs and 33 miRNAs were up-regulated and down-regulated in phloem compared to that in xylem, respectively. The functions of differentially expressed miRNAs were associated with regulating the development and differentiation of phloem and xylem. The present study provides a glance of miRNA profiles for further understanding of miRNA role in ramie development.


Assuntos
Boehmeria/genética , MicroRNAs/genética , Boehmeria/metabolismo , China , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Anotação de Sequência Molecular/métodos , Floema/genética , Proteínas de Plantas/genética , Transcriptoma/genética , Xilema/genética
14.
Water Sci Technol ; 81(6): 1159-1169, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32597403

RESUMO

Given the highly complex recalcitrant nature of synthetic dyes, biological treatment of textile wastewater using efficient bacterial species is still considered as an environmentally friendly manner. In this study, a reactive blue 19 (RB19)-degrading strain, Bacillus sp. JF4, which was isolated by resuscitation-promoting factor (Rpf) strategy, was immobilized into polyvinyl alcohol-calcium alginate-activated carbon beads (JF4-immobilized beads) for RB19 decolorization. Results suggest that the JF4-immobilized beads, which were capable of simultaneous adsorption and biodegradation, showed a high decolorization activity, while they exhibited better tolerability towards high RB19 concentrations. The JF4-immobilized beads could almost completely decolorize 100 mg/L RB19 within 10 d, while only 92.1% was decolorized by free bacteria within 12 d. Further investigation on the equilibrium and kinetics of the adsorption process suggests that the pseudo-second-order model best fit the adsorption kinetics data, and the Freundlich isotherm was the most suitable for the description of the equilibrium data. Notably, the repeated batch cycles indicated that complete decolorization of 100 mg/L RB19 by JF4-immobilized beads can be maintained for at least three cycles without much reduction in efficiency. These findings suggest that immobilizing Rpf-resuscitated strain into beads was an effective strategy for textile wastewater treatment.


Assuntos
Bacillus , Antraquinonas , Biodegradação Ambiental , Corantes
15.
Chemistry ; 25(70): 15983-15987, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31536145

RESUMO

We report a general design strategy for a new class of luminogens with dual-state emission (DSEgens) that are brightly emissive in both the solution and solid state, with solvatochromism properties, by constructing a partially shared donor-acceptor pattern based on a twisted molecule. The DSEgens with bright fluorescence emission in both the solid and solution state demonstrate a unique solvatochromism behaviour depending on solvent polarity and thus may have applications in anti-counterfeiting.

16.
Analyst ; 144(15): 4483-4487, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31270525

RESUMO

A unique diffusion-dependent emission phenomenon of gold nanoclusters was discovered, and can be regulated by the variation in viscosity and temperature. This specific property of gold nanoclusters was further used for viscosity monitoring in live cells, and the results demonstrated that gold nanoclusters are capable of real-time monitoring the abnormal viscosity change inside the cells.


Assuntos
Citoplasma/metabolismo , Ouro/química , Nanopartículas Metálicas/química , Células A549 , Microambiente Celular/fisiologia , Difusão , Glutationa/química , Humanos , Medições Luminescentes/métodos , Temperatura , Viscosidade
17.
J Nanosci Nanotechnol ; 19(2): 1026-1034, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30360194

RESUMO

Nitrogen doped nanoporous activated carbon (N-NPAC) was prepared via the facile and effective KOH activation method using Zizania latifolia (ZL), a common Chinese aquatic vegetable, as the raw material. The biomass derived N-NPAC exhibited high content of nitrogen (18.4 at%), large surface area (1493.4 m²/g) and abundant nanopores. The unique physical-chemical structure endows the N-NPAC with great application potential in adsorbents. The performance of the N-NPAC for the adsorptive removal of bisphenol A (BPA) was studied. The results showed the adsorption processes were barely affected by solution pH. The adsorption kinetics are well-fitted by the pseudo-second-order kinetic model and the adsorption isotherms followed the Langmuir isotherm model. The maximum adsorption capacity calculated by the Langmuir isotherm model is 555.5 mg/g at 313 K, demonstrating the promise of the N-NPAC for the application in water cleanup. This study provides an example using the inexpensive and abundantly available biomass as the raw materials for the large scale production of nanocarbons and paves an avenue for the development of bio-derived nanomaterials.


Assuntos
Nanoporos , Poluentes Químicos da Água , Adsorção , Compostos Benzidrílicos , Cinética , Nitrogênio , Fenóis
18.
Ecotoxicol Environ Saf ; 179: 188-197, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31048215

RESUMO

Identifying indigenous bacterial community and exploring the potential of native microorganisms are crucial for in situ bioremediation of nitrogenous pollutants in water bodies. This study evaluated the bacterial communities of sediment samples from a nitrogen polluted river, and revealed the possible environmental factors shaping the bacterial populations. Importantly, viable but non-culturable bacteria which possessed nitrogen removal capabilities in indigenous population of the sediments were explored by resuscitation promoting factor (Rpf). It was found that the sediments from upstream (URS) and lower stream (LRS) of Puyang river showed both different pollutants levels and bacterial community. Nitrate nitrogen, organic carbon and ammonium nitrogen probably had a significant effect on bacterial compositions between URS and LRS. From URS and LRS, a total of thirteen strains with heterotrophic nitrification ability were resuscitated by Rpf addition, which belonged to genera Bacillus, Pseudomonas, Stenotrophomonas and Acinetobacter. Among them, the strain Pseudomonas sp. SSPR1 was found to display high removal capabilities of simultaneous nitrification and denitrification, and the average ammonium and nitrate removal rates were 2.23 and 0.86 mg/(L·h), respectively. These resuscitated strains could be considered to be used for biological nitrogen removal in rivers and their receiving water bodies.


Assuntos
Compostos de Amônio/análise , Sedimentos Geológicos/microbiologia , Microbiota , Nitrogênio/análise , Rios/microbiologia , Poluentes Químicos da Água/análise , Acinetobacter/efeitos dos fármacos , Acinetobacter/isolamento & purificação , Aerobiose , Biodegradação Ambiental , China , Desnitrificação , Monitoramento Ambiental , Processos Heterotróficos/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Nitrificação , Pseudomonas/efeitos dos fármacos , Pseudomonas/isolamento & purificação
19.
Ecotoxicol Environ Saf ; 171: 813-822, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30660975

RESUMO

Investigating the occurrence of disinfection by-products (DBPs) and identify the related influencing factors in drinking water is essentially important to control DBPs risk. In this study, 64 tap water samples were collected from 8 counties (or county level cities) in Jinhua Region of Zhejiang Province, China. Results showed that the median (range) of trihalomethane (THMs), haloacetic acids (HAAs), haloacetonitriles (HANs), haloketones (HKs) and halonitromethanes (HNMs) were 23.2 (9.1-40.9), 15.3 (5.8-38.6), 2.2 (0.7-7.6), 2.1 (0.2-6.4) and 0.7 (0.2-2.9) µg/L, respectively. HAAs, HANs, HKs and HNMs levels were generally higher in summer than in winter or spring, while for THMs in most counties, higher levels occurred in winter than in summer or spring. Spatially, Yongkang, Yiwu and Dongyang had higher DBPs levels than Pujiang, Pan'an, Lanxi, Wuyi and Jinhua, which was generally consistent with their economy development (GDP). Correlation analysis showed that DBPs occurrence in tap water was significantly related with physicochemical parameters. Principle component analysis further suggested that organic matter (DOC and UVA254) are the major factors influencing the occurrence of THMs, HAAs, HANs and HKs in tap water, while for HNMs, both the organic (DOC and UVA254) and inorganic factors (e.g. Temp, NO2--N, pH, Br- and NH4+-N) played important role in its formation.


Assuntos
Desinfetantes/química , Água Potável/química , Poluentes Químicos da Água/química , Acetatos/análise , Acetonitrilas/análise , China , Hidrocarbonetos Halogenados/análise , Cetonas/análise , Estações do Ano , Trialometanos/análise
20.
Ecotoxicol Environ Saf ; 175: 251-262, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30903881

RESUMO

In recent years, the heavy metal ions have been immoderately released into the ecological system and result in potential hazardous to public health. Herein, the sodium dodecyl sulfate intercalated molybdenum disulfide (SDS-MoS2) was synthesized for the adsorption of Cr(VI). The SDS molecule was flat and vertically intercalated into the interlayer of MoS2, which was further evidenced by density functional theory calculations. The capture of Cr(VI) on the sphere-like SDS-MoS2 relied on solution pH. The retention of Cr(VI) on SDS-MoS2 attained 63.92 mg/g, and the removal process was endothermic, spontaneous and increased with temperature increasing. The main removal mechanism of Cr(VI) onto SDS-MoS2 was Cr(VI) fixing on the surface of the composites by chemisorption involving possible Cr-S coordination bonding. More importantly, Cr(VI) passed into the increased interlamination and reacted at the interlamination of SDS-MoS2, which was further proved at molecular level. The results can provide critical information for the application of SDS-MoS2 in Cr(VI) elimination or other kinds of pollutants removal in natural aquatic environment.


Assuntos
Cromo/análise , Dissulfetos/química , Molibdênio/química , Dodecilsulfato de Sódio/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Soluções , Propriedades de Superfície
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA