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1.
Huan Jing Ke Xue ; 45(2): 1150-1160, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471952

RESUMO

In order to evaluate the feasibility of using Burkholderia sp. Y4 as a cadmium (Cd)-reducing bacterial agent in contaminated wheat fields, the changes in the rhizosphere soil microbial community and Cd available state, as well as the content and transport characteristics of Cd in the wheat root, basal node, internode, and grain under the treatment of strain Y4 were tested using microbial high-throughput sequencing, step-by-step extraction, subcellular distribution, and occurrence analyses. The results showed that root application of strain Y4 significantly reduced the root and grain Cd content of wheat by 7.7% and 30.3%, respectively, compared with that in the control treatment. The Cd content and Cd transfer factor results in wheat vegetative organs showed that strain Y4 reduced the Cd transfer factor from basal node to internode by 79.3%, and Cd content in the wheat internode stem also decreased by 50.9%. The study of Cd occurrence morphology showed that strain Y4 treatment increased the proportion of residual Cd in roots and basal ganglia, decreased the contents of inorganic and water-soluble Cd in roots, and increased the content of residual Cd in basal ganglia. Further examination of the subcellular distribution of Cd showed that the Cd content in root cell walls and basal ganglia cell fluid increased by 21.3% and 98.2%, respectively, indicating that the Cd fixation ability of root cell walls and basal ganglia cell fluid was improved by the strain Y4 treatment. In the rhizosphere soil, it was found that the microbial community structure was changed by strain Y4 application. Under the Y4 treatment, the relative abundance of Burkholderia increased from 9.6% to 11.5%, whereas that of Acidobacteriota decreased. Additionally, the relative abundance of Gemmatimonadales, Pseudomonadales, and Chitinophagales were also increased by strain Y4 treatment. At the same time, the application of strain Y4 increased the pH value of rhizosphere soil by 8.3%. The contents of exchangeable Cd, carbonate-bound Cd, and iron-manganese oxide-bound Cd in the soil decreased by 44.4%, 21.7%, and 15.9%, respectively, whereas the proportion of residual Cd reached 53.6%. Root application of strain Y4 increased the contents of nitrate nitrogen and ammonium nitrogen in the soil by 22.0% and 21.4%, respectively, and the contents of alkaline nitrogen also increased to a certain extent. In conclusion, the root application of strain Y4 not only improved soil nitrogen availability but also inhibited Cd transport and accumulation from contaminated soil to wheat grains in a "two-stage" manner by reducing Cd availability in rhizosphere soil and improving Cd interception and fixation capacity of wheat roots and basal nodes. Therefore, Burkholderia Y4 has application potential as a Cd-reducing and growth-promoting agent in wheat.


Assuntos
Burkholderia , Compostos Férricos , Poluentes do Solo , Cádmio/análise , Triticum , Burkholderia/fisiologia , Fator de Transferência , Solo/química , Nitrogênio/análise , Poluentes do Solo/análise
2.
Chemosphere ; 355: 141828, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552800

RESUMO

Microorganisms play an important role in heavy metal bioremediation and soil fertility. The effects of soil inoculation with Pseudomonas sp. W112 on Cd accumulation in wheat were investigated by analyzing the transport, subcellular distribution and speciation of Cd in the soil and plants. Pseudomonas sp. W112 application significantly decreased Cd content in the roots, internode and grains by 10.2%, 29.5% and 33.0%, respectively, and decreased Cd transfer from the basal nodes to internodes by 63.5%. Treatment with strain W112 decreased the inorganic and water-soluble Cd content in the roots and increased the proportion of residual Cd in both the roots and basal nodes. At the subcellular level, the Cd content in the root cell wall and basal node cytosol increased by 19.6% and 61.8%, respectively, indicating that strain W112 improved the ability of the root cell wall and basal node cytosol to fix Cd. In the rhizosphere soil, strain W112 effectively colonized and significantly decreased the exchangeable Cd, carbonate-bound Cd and iron-manganese oxide-bound Cd content by 43.5%, 27.3% and 17.6%, respectively, while it increased the proportion of residual Cd by up to 65.2%. Moreover, a 3.1% and 23.5% increase in the pH and inorganic nitrogen content in the rhizosphere soil, respectively, was recorded. Similarly, soil bacterial community sequencing revealed that inoculating with strain W112 increased the abundance of Pseudomonas, Thauera and Azoarcus, which are associated with inorganic nitrogen metabolism, and decreased that of Acidobacteria, which is indicative of soil alkalinization. Hence, root application of Pseudomonas sp. W112 improved soil nitrogen availability and inhibited Cd accumulation in the wheat grains in a two-stage process: by reducing the Cd availability in the rhizosphere soil and by improving Cd interception and fixation in the wheat roots and basal nodes. Pseudomonas sp. W112 may be a suitable bioremediation agent for restoring Cd-contaminated wheat fields.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/análise , Triticum/metabolismo , Solo/química , Disponibilidade Biológica , Pseudomonas/metabolismo , Poluentes do Solo/análise , Raízes de Plantas/metabolismo , Nitrogênio/análise
3.
Brain Behav ; 14(2): e3432, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38361318

RESUMO

INTRODUCTION: Cigarette smoking increases both the risk for insulin resistance and amyloid-ß (Aß) aggregation, and impaired brain insulin/insulin-like growth factor 1 (IGF1) signaling might increase risk factors for Alzheimer's disease (AD). We aimed to investigate the association among cerebrospinal fluid (CSF) insulin sensitivity/IGF1, glucose/lactate, and Aß42 and further explore whether insulin sensitivity contributed to the risk for AD in active smokers. METHODS: In this cross-sectional study, levels of insulin, IGF1, and lactate/glucose of 75 active smokers and 78 nonsmokers in CSF were measured. Three polymorphisms regulating IGF1 were genotyped. Analysis of variance was used to compare differences of variables between groups. Partial correlation was performed to test the relationship between CSF biomarkers and smoking status. General linear models were applied to test the interaction of the effect of single nucleotide polymorphisms and cigarette smoking on CSF IGF1 levels. RESULTS: In the CSF from active smokers, IGF1 and lactate levels were significantly lower (p = .016 and p = .010, respectively), whereas Aß42 (derived from our earlier research) and insulin levels were significantly higher (p < .001 and p = .022, respectively) as compared to the CSF from nonsmokers. The AG + GG genotype of rs6218 in active smokers had a significant effect on lower CSF IGF1 levels (p = .004) and lower CSF insulin levels in nonsmokers (p = .016). CONCLUSIONS: Cigarette smoking as the "at-risk" factor for AD might be due to lower cerebral insulin sensitivity in CSF, and the subjects with rs6218G allele seem to be more susceptible to the neurodegenerative risks for cigarette smoking.


Assuntos
Doença de Alzheimer , Fumar Cigarros , Resistência à Insulina , Humanos , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/epidemiologia , Biomarcadores/líquido cefalorraquidiano , Fumar Cigarros/líquido cefalorraquidiano , Estudos Transversais , Glucose/líquido cefalorraquidiano , Insulina/líquido cefalorraquidiano , Lactatos/líquido cefalorraquidiano , Fator de Crescimento Insulin-Like I/líquido cefalorraquidiano
4.
Toxicol Appl Pharmacol ; 484: 116860, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342444

RESUMO

Difenoconazole (DFZ) is a fungicidal pesticide extensively employed for the management of fungal diseases in fruits, vegetables, and cereal crops. However, its potential environmental impact cannot be ignored, as DFZ accumulation is able to lead to aquatic environment pollution and harm to non-target organisms. Quercetin (QUE), a flavonoid abundant in fruits and vegetables, possesses antioxidant and anti-inflammatory properties. In this article, carp were exposed to 400 mg/kg QUE and/or 0.3906 mg/L DFZ for 30 d to investigate the effect of QUE on DFZ-induced respiratory toxicity in carp. Research shows that DFZ exposure increases reactive oxygen species (ROS) production in the carp's respiratory system, leading to oxidative stress, inflammation, and damage to gill tissue and tight junction proteins. Further research demonstrates that DFZ induces mitochondrial dynamic imbalance and gill cell apoptosis. Notably, QUE treatment significantly reduces ROS levels, alleviates oxidative stress and inflammation, and mitigates mitochondrial dynamics imbalance and mitochondrial apoptosis. This study emphasizes the profound mechanism of DFZ toxicity to the respiratory system of common carp and the beneficial role of QUE in mitigating DFZ toxicity. These findings contribute to a better understanding of pesticide risk assessment in aquatic systems and provide new insights into strategies to reduce their toxicity.


Assuntos
Carpas , Dioxolanos , Praguicidas , Triazóis , Animais , Quercetina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Dinâmica Mitocondrial , Carpas/metabolismo , Antioxidantes/farmacologia , Estresse Oxidativo , Inflamação , Sistema Respiratório , Apoptose
5.
J Ethnopharmacol ; 319(Pt 3): 117317, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37832809

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Although therapeutic hypothermia is currently considered an effective treatment for neonatal hypoxic-ischemic encephalopathy (HIE), neonatal HIE is a disease requiring multiple therapeutic measures. Related Chinese herbal injections (CHIs) have been carried out in Chinese local hospitals for several years, and the outcomes all seem to show positive results. At the same time, other Traditional Chinese medicine (TCM) methods have also shown vigorous vitality. AIM OF THE STUDY: This study constructed a network meta-analysis (NMA) to investigate the efficacy of CHIs including Shenmai Injection (SMI), Compound musk injection (SXI), Ligustrazine injection (CXI), Compound danshen injection (DSI), Astragalus injection (HQI), Ginkgo biloba extract injection (YXI), and Puerarin injection (GGI) combined with traditional symptomatic treatment (TST) and TST alone in HIE. METHODS: A literature review was conducted in several databases from inception to 9 February 2023. The quality of the included studies was assessed by the Cochrane risk of bias tool. Data were analyzed by STATA 17.0 and R 4.2.2 software. Surface under the cumulative ranking curve (SUCRA) probability values were applied to rank the examined treatments. Bayesian network meta-analysis was designed to access the effectiveness of different CHIs. RESULTS: A total of 46 eligible randomized controlled trials involving 3,448 patients and 7 CHIs were included. The results of the NMA showed that SMI, SXI, CXI, DSI, HQI, YXI, and GGI combined with TST significantly improved treatment performance compared to TST alone. SMI + TST had obvious superiorities in the clinical effective rate and the original reflection recovery time. SXI + TST was the most advantageous in the Cure rate and the Neonatal Behavioral Neurological Assessment (NBNA). CXI + TST was shown to reduce the incidence of sequelae best. All articles reported that there were no obvious adverse drug reactions/adverse drug events (ADRs/ADEs). CONCLUSION: This NMA showed that using CHIs in combination with TST improved treatment performance and could be beneficial for patients with HIE compared to using TST alone. Thereinto, SXI + TST showed a preferable improvement in patients with HIE when unified considering the clinical effective rate and other outcomes. As for safety, more evidence is needed to support this hypothesis.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Hipóxia-Isquemia Encefálica , Recém-Nascido , Humanos , Medicina Tradicional Chinesa , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Teorema de Bayes , Metanálise em Rede
6.
Funct Integr Genomics ; 23(4): 329, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910254

RESUMO

Improved chondrogenic differentiation of mesenchymal stem cells (MSCs) by genetic regulation is a potential method for regenerating articular cartilage. LncRNA MIR22HG has been proven to accelerate osteogenic differentiation, but the regulation mechanism of chondrogenic differentiation is still unclear. Human adipose-derived stem cells (hADSCs) have been widely utilised for bone tissue engineering applications. The present study aimed to examine the effect of MIR22HG on the chondrogenic differentiation of hADSCs. The results confirmed that MIR22HG was downregulated in the process of chondrogenic differentiation. Subsequently, gain- and loss-of-function of MIR22HG experiments showed that the overexpression of MIR22HG suppressed the deposition of cartilage matrix proteoglycans and decreased the expression of cartilage-related markers (e.g. Sox9, ACAN and Col2A1), whereas the knockdown of MIR22HG had the opposite effect. MIR22HG could bind to CTCF (CCCTC-binding factor), and CTCF could bind to the CRLF1 (cytokine receptor-like factor 1) promoter and upregulate CRLF1 gene expression. Besides, inhibition of CRLF1 can reverse the effect of MIR22HG on cell chondrogenic differentiation of hADSCs. Taken together, our outcomes reveal that MIR22HG suppressed chondrogenic differentiation by interaction with CTCF to stabilise CRLF1.


Assuntos
Células-Tronco Mesenquimais , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Osteogênese , Fator de Ligação a CCCTC/genética , Fator de Ligação a CCCTC/metabolismo , Fator de Ligação a CCCTC/farmacologia , Diferenciação Celular/genética , Células-Tronco Mesenquimais/metabolismo , Células Cultivadas
7.
Pestic Biochem Physiol ; 196: 105590, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945241

RESUMO

The increasing concern over environmental pollution caused by the pesticide avermectin used in aquaculture has attracted significant attention. The use of avermectin, a neurotoxic pesticide, in aquatic environments leads to toxic effects on non-target organisms, particularly causing harm to fish. The phenolic compound ferulic acid possesses excellent anti-inflammatory and antioxidant capabilities. This study was conducted by establishing a chronic exposure experiment to avermectin, proposes the use of ferulic acid as a dietary additive to protect the carp brain from damage caused by exposure to avermectin. Furthermore, it investigates the anti-inflammatory and antioxidant effects of ferulic acid in the carp brain under chronic exposure to avermectin. The experimental results demonstrate that ferulic acid can alleviate brain tissue inflammation and oxidative stress by modulating the Nrf2/Keap1 and NF-κB signaling pathways. It protects the carp brain from chronic avermectin-induced damage, preserves the integrity of the carp blood-brain barrier, enhances the levels of feeding factors, and thereby alleviates carp growth inhibition. These findings provide new therapeutic strategies and a theoretical foundation for the sustainable development of carp aquaculture.


Assuntos
Carpas , Praguicidas , Animais , NF-kappa B/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Imunidade Inata , Carpas/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Transdução de Sinais , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Estresse Oxidativo , Anti-Inflamatórios , Encéfalo/metabolismo , Proteínas de Peixes/metabolismo
8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(9): 1134-1139, 2023 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-37643961

RESUMO

OBJECTIVE: To explore the clinical characteristics and genetic basis for a child with X-linked lissencephaly with abnormal genitalia (XLAG). METHODS: A child with XLAG who had presented at the Third Affiliated Hospital of Zhengzhou University in May 2021 was selected as the study subject. Peripheral blood samples of the child and his parents were collected and subjected to high-throughput sequencing. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the result was analyzed by using bioinformatic software. RESULTS: The child was found to have harbored a hemizygous c.945_948del variant in exon 2 of the ARX gene, which as a frameshifting variant has resulted in a truncated protein. His mother was found to be heterozygous for the variant, whilst his father was of wild type. The variant was unreported previously. CONCLUSION: The hemizygous c.945_948del variant of the ARX gene probably underlay the XLAG in this patient. Above finding has provided a basis for the diagnosis and genetic counseling for this family.


Assuntos
Lissencefalias Clássicas e Heterotopias Subcorticais em Banda , Humanos , Criança , Éxons , Biologia Computacional , Aconselhamento Genético , Genitália , Fatores de Transcrição , Proteínas de Homeodomínio
9.
J Orthop Surg Res ; 18(1): 430, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37312126

RESUMO

BACKGROUND: Tumor necrosis factor-alpha (TNF-α), one of the pro-inflammatory cytokines mediating the local inflammatory process in joints, inhibits cartilage formation and has a detrimental effect on stem cell-based cartilage regeneration for the treatment of osteoarthritis (OA). However, the mechanisms behind this inhibitory effect are still poorly understood. Mitochondrial morphological changes mediated by mitochondrial fusion and fission are highly plastic, are quite sensitive to environmental stimuli and play a crucial role in maintaining cell structure and function. In our study, chondrogenic differentiated human adipose stem cells (hADSCs) were exposed to TNF-α and the effect of TNF-α on the ability of hADSCs to chondrogenic differentiate and on mitochondrial fusion and fission was observed and analyzed. The aim was to investigate the role and mechanisms of mitochondrial fusion and fission regulation in the chondrogenic differentiation of hADSCs under normal conditions and under exposure to TNF-α. METHODS: We used flow cytometry to identify hADSCs immunophenotypes CD29, CD44, CD34, CD45, and HLA-DR. Alcian blue staining and Sirius red staining were used to observe the formation of proteoglycans and collagen during the chondrogenic differentiation of hADSCs, respectively. The mRNA and protein expression levels of the cartilage formation marker SOX9, type II collagen (COL2A1), and Aggrecan were measured by real-time fluorescent quantitative PCR (RT-qPCR) and western blot, respectively. The fluorescent probes MitoTracker® Red CMXRos and JC-1 were used to visualize mitochondria morphology and detect mitochondrial membrane electricity (MMP). Affymetrix PrimeView™ chips were used for gene expression profiling. RESULTS: The results showed that the chondrogenic differentiation of hADSCs was inhibited in the presence of TNF-α that optic atrophy 1 (OPA1) expression was significantly upregulated and mitochondria were prolonged and interconnected during this process. Gene microarray and RT-qPCR data showed that the presence of TNF-α led to increased expression of TNFα receptor 2 (TNFRSF1B) and RELA during chondrogenic differentiation of hADSCs. CONCLUSIONS: TNF-α inhibits chondrogenic differentiation of human adipose stem cells by activating RELA expression through TNFRSF1B upregulating OPA1 expression thereby increasing mitochondrial fusion.


Assuntos
Adipócitos , Fator de Necrose Tumoral alfa , Humanos , Fator de Necrose Tumoral alfa/farmacologia , Diferenciação Celular/genética , Citocinas , Mitocôndrias , GTP Fosfo-Hidrolases , Receptores Tipo II do Fator de Necrose Tumoral , Fator de Transcrição RelA
10.
Front Microbiol ; 14: 1102907, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37333657

RESUMO

Klebsiella aerogenes is a common infectious bacterium that poses a threat to human health. Nevertheless, there are limited data on the population structure, genetic diversity, and pathogenicity of K. aerogenes, especially among men who have sex with men (MSM). The present study aimed to clarify the sequence types (STs), clonal complexes (CCs), resistance genes, and virulence factors of popular strains. Multilocus sequence typing was used to describe the population structure of K. aerogenes. The Virulence Factor Database and Comprehensive Antibiotic Resistance Database were used to assess the virulence and resistance profiles. In this study, next-generation sequencing was performed on nasal swabs specimens collected in an HIV Voluntary Counseling Testing outpatient department in Guangzhou, China, from April to August 2019. The identification results showed that a total of 258 K. aerogenes isolates were collected from 911 participants. We found that the isolates were most resistant to furantoin (89.53%, 231/258) and ampicillin (89.15%, 230/258), followed by imipenem (24.81%, 64/258) and cefotaxime (18.22%, 47/258). The most common STs in carbapenem-resistant K. aerogenes were ST4, ST93, and ST14. The population has at least 14 CCs, including several novel ones identified in this study (CC11-CC16). The main mechanism of drug resistance genes was antibiotic efflux. Based on the presence of the iron carrier production genes irp and ybt, we identified two clusters according to virulence profiles. In cluster A, CC3 and CC4 carry the clb operator encoding the toxin. Increased monitoring is needed for the three main ST type strains carried by MSM. The main clone group CC4 has a large number of toxin genes, and it spreads among MSM. Caution is needed to prevent further spread of this clone group in this population. In sum, our results may provide a foundation for the development of new therapeutic and surveillance strategies for treating MSM.

11.
Huan Jing Ke Xue ; 44(5): 2879-2888, 2023 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-37177959

RESUMO

Shanxi is one of the main producing areas of Forsythia suspensa in China. In order to explore the safety of the soil in the areas where Forsythia suspensa grows,70 surface (0-25 cm) soil samples were collected from the main growing areas of F. suspensa in the eastsouth of Shanxi Province in July 2017. The concentration and composition characteristics of 16 polycyclic aromatic hydrocarbons (PAHs) in the sample soils were analyzed using chemical extraction and gas chromatography-mass spectrometry (GC-MS). The diagnostic ratio method was used to determine the source of PAHs in the areas. The potential ecological risk was assessed by using the method of calculating the equivalent carcinogenic concentration of benzo[a]pyrene. The results showed that the average concentration of total PAHs (Σ16PAHs) in all of the soil samples was 1.85 µg·g-1, which was dominated by three ring number PAHs, accounting for 76.7% of the total PAHs. The detection rates of phenanthrene (Phe) and anthracene (Ant) were both 100% of all the sample sites. The soil PAHs in the wild F. suspensa growing areas mainly originated from coal, biomass burning, and motor vehicle exhaust emissions, which resulted from air transport and sedimentation pathways. In all of the sample sites, the concentration of Σ16PAHs the limit standard level (0.2 µg·g-1) of Maliszewska-Kordybach for agricultural soil pollution and exceeded the soil heavy pollution level limit value (1.0 µg·g-1) in 41.4% of the sample sites. The concentration of BaP was above the risk control standard for soil contamination of agricultural land (0.55 µg·g-1) in 10% of all the soil samples. A total of 11.4% of the sample soil ΣBaPeq16PAHs and ΣBaPeq8BPAHs exceeded the agricultural soil screening value (0.55 µg·g-1). These results indicate that the contamination of PAHs was at a detectable level in the soil of wild F. suspensa growing in Shanxi, and thus their potential ecological risks should not be ignored. It is necessary to enhance the research regarding these areas to ensure the safe production of medicinal plants.


Assuntos
Forsythia , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo/química , Monitoramento Ambiental/métodos , Poluentes do Solo/análise , China , Emissões de Veículos/análise , Poluição Ambiental/análise , Medição de Risco
12.
Talanta ; 260: 124569, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37116360

RESUMO

Single-molecule detection (SMD) aims to achieve the ultimate limit-of-detection (LOD) in biosensing. This method detects a countable number of targeted analyte molecules in solution, where the dynamics of molecule diffusion, capturing, identification and delivery greatly impact the SMD's efficiency and accuracy. In this study, we adopt the first-passage time method to investigate the diffusion-controlled reaction process in SMD. We analyze the influence of detection conditions on incubation time and the expected coefficient of variation (CV) under three SMD molecule capturing strategies, including solid-phase capturing (one-dimensional solid-liquid interface fixation), liquid-phase magnetic bead (MB) capturing, and liquid-phase direct fluorescence pair labeling. We find that inside a finite-sized reaction chamber, a finite average reaction time exists in all three capturing strategies, while the liquid-phase strategies are in general more efficient than the solid-phase approaches. CV can be estimated by averaging first-passage time solely in all three strategies, and the CV reduction is achievable given an extended reaction time. To further enable zeptomolar detection, extra treatments, such as adopting liquid-phase fluorescence pairs with high diffusion rates to label the molecule, or designing specific sensing devices with large effective sensing areas would be required. This framework provides solid theoretical support to guide the design of SMD sensing strategies and sensor structures to achieve desired measurement time and CV.


Assuntos
Técnicas Biossensoriais , Fluorescência
13.
J Colloid Interface Sci ; 641: 155-165, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36931214

RESUMO

Developing highly efficient, sustainable carbon cathodes is essential for emerging Zn-ion hybrid supercapacitors (ZICs). Herein, lignin's novel chemical modification (amination) has been developed to produce high quantity pyrrolic-N moieties as active sites. Furthermore, chemically modified amine moieties in lignin are vital as a natural self-activating template to generate hierarchical porosity in the 2D (graphene-like) architecture with exceedingly high surface area (2926.4 m2g-1). The rationally introduced dominated pyrrolic-N moieties boost the Zn-ion storage capacity and reaction kinetics due to the dual energy storage mechanism and efficient charge transfer between pyrrolic-N and Zn+2 ions. Furthermore, the pyrrolic-N species are energetically favorable for the adsorption of Zn+2 ions by the formation of N-Zn+2 chemical bonds. Besides, the nitrogen oxides reduce the intrinsic resistance and induce a more polarized surface, resulting in high wettability and efficient transfer of electrolytes into the pores of hydrophobic carbon materials. Subsequently, the chemically modified lignin-derived activated carbon material (Chem-ACM) as a cathode in ZICs delivers a high capacity of 161.2 mA h g-1 at 1 A g-1 with the admirable energy density of 106.7 W h kg-1 at 897 W kg-1 and excellent retention capacity (94%) after 10,000 cycles. Mainly, the assembled quasi solid-state ZICs using Chem-ACM retains the remarkable storage capacity (202 mA h g-1 at 0.2 Ag-1) even at a high bending angle. Notably, the Chem-ACM has been further employed in symmetric supercapacitors as an electrode, and it displays exceptional specific capacitance of 354 Fg-1 at 0.5 Ag-1 with tremendous energy (43.5 W h kg-1) and the power density (0.53 kW kg-1). Additionally, the charge storage capability of Chem-ACM is positively dependent on high nitrogen contents, and it is extrapolated that pyrrolic-N moieties are dominant active sites. Hence, the designed amination-assisted biocarbon synthesis provides a new way to prepare high nitrogen-containing biocarbon for ZICs and further understand pyrrolic-N species' impact on Zn-ion storage.

14.
Int J Biol Macromol ; 238: 124031, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36933599

RESUMO

Actuators are widely used in bionic devices and soft robots, among which invisible actuators have some unique applications, including performing secret missions. In this paper, highly visible transparent cellulose-based UV-absorbing films were prepared by dissolving cellulose raw materials using N-methylmorpholine-N-oxide (NMMO) and using ZnO nanoparticles as UV absorbers. Furthermore, transparent actuator was fabricated by growing highly transparent and hydrophobic polytetrafluoroethylene (PTFE) film on regenerated cellulose (RC)-ZnO composite film. In addition to its sensitive response to Infrared (IR) light, the as-prepared actuator also shows a highly sensitive response to UV light, which is attributed to the strong absorption of UV light by ZnO NPs. Thanks to the drastic differences in adsorption capacity between the RC-ZnO and PTFE materials for water molecules, the asymmetrically- assembled actuator demonstrates extremely high sensitivity and excellent actuation performance, with a force density of 60.5, a maximum bending curvature of 3.0 cm-1, and a response time of below 8 s. Bionic bug, smart door and the arm of excavator made from the actuator all exhibit sensitive responses to UV and IR lights.


Assuntos
Nanopartículas , Óxido de Zinco , Raios Ultravioleta , Celulose/química , Água/química , Nanopartículas/química
15.
Nano Lett ; 23(6): 2253-2261, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36729707

RESUMO

Upconversion nanoparticles (UCNPs) have been frequently applied in Förster resonance energy transfer (FRET) bioanalysis. However, the understanding of how surface coatings, bioconjugation, and dye-surface distance influence FRET biosensing performance has not significantly advanced. Here, we investigated UCNP-to-dye FRET DNA-hybridization assays in H2O and D2O using ∼24 nm large NaYF4:Yb3+,Er3+ UCNPs coated with thin layers of silica (SiO2) or poly(acrylic acid) (PAA). FRET resulted in strong distance-dependent PL intensity changes. However, the PL decay times were not significantly altered because of continuous Yb3+-to-Er3+ energy migration during Er3+-to-dye FRET. Direct bioconjugation of DNA to the thin PAA coating combined with the closest possible dye-surface distance resulted in optimal FRET performance with minor influence from competitive quenching by H2O. The better comprehension of UCNP-to-dye FRET was successfully translated into a microRNA (miR-20a) FRET assay with a limit of detection of 100 fmol in a 80 µL sample volume.


Assuntos
Técnicas Biossensoriais , Nanopartículas , Ácidos Nucleicos , Transferência Ressonante de Energia de Fluorescência , Dióxido de Silício , Técnicas Biossensoriais/métodos
16.
Chinese Journal of School Health ; (12): 498-501, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-972731

RESUMO

Objective@#To explore the effect of the comprehensive intervention on overweight and obesity among middle school students at the population level (health education lecture and official account push) and individual level (personalized dietary guidance), so as to provide a reference for preventing and controlling their overweight and obesity.@*Methods@#Three junior high schools and three senior high schools were randomly selected in Guangzhou in 2018 by convenience sampling. Through physical examination, 1 457 overweight and obese students aged from 12 to 18 years old were screened. Intervention was administered through "Student Personalized Dietary Guidance" manual, health tweets on the official accounts, and health education lectures from September 2018 to December 2019. The Chi square test was used to compare the difference in overweight and obesity constituent ratio between the two groups before and after the intervention. And intervention effect was evaluated by analyzing the number needed to treated(NTT).@*Results@#The proportion of overweight before the intervention was 66.71% (972/1 457), and decreased to 59.92% (873/1 457) after the intervention; the proportion of obesity before the intervention was 33.29% (485/1 457), which decreased to 26.63% (388/1 457) after the intervention. Among obese students, the smallest NNT was seen in the girl group aged 12-13 years (NNT=2.6, 95% CI =1.9-4.1), while the largest NNT in the boy group aged 14-18 years (NNT=5.9, 95% CI =4.7-8.1). The NNT of the girls aged 12-13 years was the smallest (NNT=2.7, 95% CI =2.2-3.5), and the NNT of the boys aged 14-18 years was the largest (NNT=7.4, 95% CI =6.0-9.7).@*Conclusion@#Health education at population level (health education lectures, official account push) with individual level (personalized dietary guidance) can effectively intervene overweight and obesity among middle school students in Guangzhou.

17.
Small ; 18(47): e2203354, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36180408

RESUMO

The ambient air-processed preparation of kesterite Cu2 ZnSn(S,Se)4 (CZTSSe) thin film is highly promising for the fabrication of low-cost and eco-friendly solar cells. However, the Sn volatilization loss and formation of a thick Mo(S,Se)2 interfacial layer during the traditional selenization process pose challenges for fabricating high-efficiency CZTSSe solar cells. Here, CZTS precursors prepared by a sol-gel process in ambient air are selenized and assisted with SnSe2 vapor via one- and two-step selenization to prepare a CZTSSe absorber on a Mo film and, subsequently, solar cells. For one-step selenization, the thickness of the fine grain and Mo(S,Se)2 layers near the back contact can be significantly reduced with increasing SnSe2 vapor partial pressure in the mixed selenization atmosphere, while the device efficiency is only 7.97% due to the severe interface recombination. For two-step selenization, the desired morphology and stoichiometry of the absorber can be achieved through the assistance of Sn-poor precursors selenized with high SnSe2 vapor partial pressure to regulate the Sn content in CZTSSe, yielding the highest efficiency of 10.85%. This study improves the understanding of the key role of the microenvironment during film growth towards the production of high-efficiency thin film solar cells and other photoelectronic devices.

18.
J Gastrointest Oncol ; 13(4): 1782-1792, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36092349

RESUMO

Background: Colon adenocarcinoma (COAD) is an incurable malignancy and the third most common tumor worldwide. Advances in biomarkers screening have greatly contributed to explore the new diagnostic and prognostic biomarkers for the early detection and prognostic of COAD. However, the heterogeneity-specific nature of COAD in patients of different cancer stages, different races, genders and age are still the major challenge to clinical treatment. Methods: Gene expression, copy number (CN), and dependency score (DS) data were obtained from the Cancer Cell Line Encyclopedia (CCLE), and linear regression analyses were performed using R language. We conducted receiver operating characteristic (ROC) curve analysis and compared the area under the ROC curve area under the curve (AUC) values to evaluate the sensitivity and specificity of nuclear cap binding protein subunit 2 (NCBP2) for the diagnosis of COAD in The Cancer Genome Atlas (TCGA) database. Survival analysis was performed in the distinct NCBP2 expression groups. In vitro experiments and bioinformatics analysis were used to investigate the molecular mechanisms of NCBP2 in COAD and its biological roles. A Connectivity Map (Cmap) was used to identify potential small molecule targeted drugs for NCBP2 in COAD. Results: Through the linear regression analysis of DS, CN, and gene expression, we determined that NCBP2 met our criteria. The mean AUC of the ROC curve of NCBP2 was 0.940±0.050. Survival analysis showed that high NCBP2 expression was associated with a worse prognosis [hazard ratio (HR) =1.98, P<0.007]. NCBP2 knockdown inhibited COAD cell proliferation and caused G0/G1 phase arrest in COAD cells. Conclusions: NCBP2 was the novel diagnostic and prognostic biomarker of in COAD. Our research had implications for the treatment of colon cancer.

19.
Phys Rev E ; 106(1): L012603, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35974529

RESUMO

The active Brownian particle (ABP) model describes a swimmer, synthetic or living, whose direction of swimming is a Brownian motion. The swimming is due to a propulsion force, and the fluctuations are typically thermal in origin. We present a two-dimensional model where the fluctuations arise from nonthermal noise in a propelling force acting at a single point, such as that due to a flagellum. We take the overdamped limit and find several modifications to the traditional ABP model. Since the fluctuating force causes a fluctuating torque, the diffusion tensor describing the process has a coupling between translational and rotational degrees of freedom. An anisotropic particle also exhibits a mass-dependent noise-induced drift, which does not disappear in the overdamped limit. We show that these effects have measurable consequences for the long-time diffusivity of active particles, in particular adding a contribution that is independent of where the force acts.

20.
Nat Commun ; 13(1): 4935, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999227

RESUMO

Control over the copy number and nanoscale positioning of quantum dots (QDs) is critical to their application to functional nanomaterials design. However, the multiple non-specific binding sites intrinsic to the surface of QDs have prevented their fabrication into multi-QD assemblies with programmed spatial positions. To overcome this challenge, we developed a general synthetic framework to selectively attach spatially addressable QDs on 3D wireframe DNA origami scaffolds using interfacial control of the QD surface. Using optical spectroscopy and molecular dynamics simulation, we investigated the fabrication of monovalent QDs of different sizes using chimeric single-stranded DNA to control QD surface chemistry. By understanding the relationship between chimeric single-stranded DNA length and QD size, we integrated single QDs into wireframe DNA origami objects and visualized the resulting QD-DNA assemblies using electron microscopy. Using these advances, we demonstrated the ability to program arbitrary 3D spatial relationships between QDs and dyes on DNA origami objects by fabricating energy-transfer circuits and colloidal molecules. Our design and fabrication approach enables the geometric control and spatial addressing of QDs together with the integration of other materials including dyes to fabricate hybrid materials for functional nanoscale photonic devices.


Assuntos
Nanoestruturas , Pontos Quânticos , Corantes , DNA/química , DNA de Cadeia Simples , Nanoestruturas/química , Pontos Quânticos/química
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