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1.
Nat Protoc ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237831

RESUMO

One of the foremost challenges in nanobiotechnology is obtaining direct evidence of nanoparticles' absorption and internalization in plants. Although confocal laser scanning microscopy (CLSM) or transmission electron microscopy (TEM) are currently the most commonly used tools to characterize nanoparticles in plants, subjectivity of researchers, incorrect sample handling, inevitable fluorescence leakage and limitations of imaging instruments lead to false positives and non-reproducibility of experimental results. This protocol provides an easy-to-operate dual-step method, combining CLSM for macroscopic tissue examination and TEM for cellular-level analysis, to effectively trace single particles in plant roots with accuracy and precision. In addition, we also provide detailed methods for processing plant materials before imaging, including cleaning, and staining, to maximize the accuracy and reliability of imaging. This protocol involves currently commonly used nanomaterial types, such as metal-based and doped carbon-based materials, and enables accurate localization of nanoparticles with different sizes at the cell level in Arabidopsis thaliana root samples either through contrast or element mapping analysis. It serves as a valuable reference and benchmark for scholars in plant science, chemistry and environmental studies to understand the interaction between plant roots and nanomaterials and to detect the distribution of nanomaterials in plants. Excluding plant culture time, the protocol can be completed in 4-5 d.

2.
ACS Nano ; 18(24): 15661-15670, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38841753

RESUMO

Methanogenic archaea, characterized by their cell membrane lipid molecules consisting of isoprenoid chains linked to glycerol-1-phosphate via ether bonds, exhibit exceptional adaptability to extreme environments. However, this distinct lipid architecture also complicates the interactions between methanogenic archaea and nanoparticles. This study addresses this challenge by exploring the interaction and transformation of selenium nanoparticles (SeNPs) within archaeal Methanosarcina acetivorans C2A. We demonstrated that the effects of SeNPs are highly concentration-dependent, with chemical stimulation of cellular processes at lower SeNPs concentrations as well as oxidative stress and metabolic disruption at higher concentrations. Notably, we observed the formation of a protein corona on SeNPs, characterized by the selective adsorption of enzymes critical for methylotrophic methanogenesis and those involved in selenium methylation, suggesting potential alterations in protein function and metabolic pathways. Furthermore, the intracellular transformation of SeNPs into both inorganic and organic selenium species highlighted their bioavailability and dynamic transformation within archaea. These findings provide vital insights into the nano-bio interface in archaeal systems, contributing to our understanding of archaeal catalysis and its broader applications.


Assuntos
Methanosarcina , Nanopartículas , Selênio , Selênio/química , Selênio/metabolismo , Methanosarcina/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Estresse Oxidativo
3.
Front Psychol ; 15: 1372694, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38882513

RESUMO

Background: The interplay between teaching engagement and performance has garnered attention in both theoretical and empirical research, primarily due to its influence on student academic achievement, teacher well-being, and the realization of institutional goals. This is especially pertinent in the realm of preschool education, where the scope of learning extends beyond academic content to encompass the broader socialization of children. Drawing from Affective Neuroscience research, this study investigates the role of affective tendencies as mediators in the relationship between work engagement and job performance. Objective: The primary aim of this research is to examine a chain mediation model that hypothesizes the predictive role of teacher engagement. This model posits the intermediary influence of four basic emotions-CARING, SEEKING, ANGER, and FEAR-followed by the mediating effect of job satisfaction on teacher job performance. Method: The study utilized a sample of 842 Chinese preschool teachers. Data were collected through an online questionnaire, employing a time-lagged design. The analysis was conducted using Model 80 of the PROCESS Macros. Results: The findings reveal that both positive and negative emotions significantly predict teachers' job satisfaction. However, job satisfaction does not influence job performance. The analysis confirmed the direct and total effects of teacher engagement, as well as the indirect effects, particularly through the positive emotion of Caring. Implications: The results are instrumental in informing and refining interventions designed to enhance teacher engagement and performance, underscoring the importance of emotional factors in the educational environment.

4.
Anal Chem ; 96(22): 8981-8989, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38758609

RESUMO

Addressing the challenge of understanding how cellular interfaces dictate the mechanical resilience and adhesion of archaeal cells, this study demonstrates the role of the surface layer (S-layer) in methanogenic archaea. Using a combination of atomic force microscopy and single-cell force spectroscopy, we quantified the impact of S-layer disruption on cell morphology, mechanical properties, and adhesion capabilities. We demonstrate that the S-layer is crucial for maintaining cell morphology, where its removal induces significant cellular enlargement and deformation. Mechanical stability of the cell surface is substantially compromised upon S-layer disruption, as evidenced by decreased Young's modulus values. Adhesion experiments revealed that the S-layer primarily facilitates hydrophobic interactions, which are significantly reduced after its removal, affecting both cell-cell and cell-bubble interactions. Our findings illuminate the S-layer's fundamental role in methanogen architecture and provide a chemical understanding of archaeal cell surfaces, with implications for enhancing methane production in biotechnological applications.


Assuntos
Microscopia de Força Atômica , Análise de Célula Única , Propriedades de Superfície , Archaea/química , Archaea/metabolismo , Adesão Celular , Interações Hidrofóbicas e Hidrofílicas
5.
ACS Nano ; 18(18): 11828-11836, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38659192

RESUMO

As essential primary producers, cyanobacteria play a major role in global carbon and nitrogen cycles. Though the influence of nanoplastics on the carbon metabolism of cyanobacteria is well-studied, little is known about how nanoplastics affect their nitrogen metabolism, especially under environmentally relevant nitrogen concentrations. Here, we show that nitrogen forms regulated growth inhibition, nitrogen consumption, and the synthesis and release of microcystin (MC) in Microcystis aeruginosa exposed to 10 µg/mL amino-modified polystyrene nanoplastics (PS-NH2) with a particle size of 50 nm under environmentally relevant nitrogen concentrations of nitrate, ammonium, and urea. We demonstrate that PS-NH2 inhibit M. aeruginosa differently in nitrate, urea, and ammonium, with inhibition rates of 51.87, 39.70, and 36.69%, respectively. It is caused through the differences in impairing cell membrane integrity, disrupting redox homeostasis, and varying nitrogen transport pathways under different nitrogen forms. M. aeruginosa respond to exposure of PS-NH2 by utilizing additional nitrogen to boost the production of amino acids, thereby enhancing the synthesis of MC, extracellular polymeric substances, and membrane phospholipids. Our results found that the threat of nanoplastics on primary producers can be regulated by the nitrogen forms in freshwater ecosystems, contributing to a better understanding of nanoplastic risks under environmentally relevant conditions.


Assuntos
Microcystis , Nitrogênio , Microcystis/efeitos dos fármacos , Microcystis/metabolismo , Microcystis/crescimento & desenvolvimento , Nitrogênio/química , Nitrogênio/metabolismo , Microcistinas/metabolismo , Poliestirenos/química , Tamanho da Partícula , Microplásticos/metabolismo , Nanopartículas/química , Nitratos/metabolismo , Nitratos/química , Ureia/metabolismo , Ureia/química , Ureia/farmacologia
6.
Int J Dermatol ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632699

RESUMO

BACKGROUND: Generalized pustular psoriasis (GPP) is a rare, potentially life-threatening skin disease often requiring long-term therapy. We aimed to evaluate the use of Interleukin (IL)-17A inhibitors (secukinumab and ixekizumab) in GPP patients over 96 weeks. METHODS: We retrospectively analyzed a case series of 18 patients with GPP who received secukinumab (n = 13) and ixekizumab (n = 5) therapy with a 96-week follow-up period. The primary effectiveness analysis included determining the percentage of patients who achieved ≥90% or 100% improvement in the Generalized Pustular Psoriasis Area and Severity Index (GPPASI) score. Adherence was captured using the medication possession ratio (MPR). RESULTS: Using the as-observed (AO) method, 87% and 67% of patients treated with secukinumab or ixekizumab achieved GPPASI 90 and 100 responses, respectively. At Week 96, the mean GPPASI improvements from baseline GPPASI were 96.3% (95% CI: 0.91-1.01) using the AO method. After Week 48, 14 patients tapered (n = 8) or terminated (n = 6) the treatment. High-adherence therapy (MPR ≥ 80%) was significantly superior to the low-adherence group in the rate of patients achieving a GPPASI 100 response (AO, 100% vs. 38%, P < 0.05). By Week 96, 5 (27.8%) patients had new GPP flares, and 4 (80%) were in the low-adherence group. No new safety signals occurred. CONCLUSION: IL-17A inhibitors led to effective and sustained improvement in GPP patients, and high-adherence therapy had long-term positive effects on skin clearance. Given its relapsing nature, improving compliance is beneficial for long-term clinical management.

7.
J Rheumatol ; 51(7): 678-681, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38490673

RESUMO

OBJECTIVE: To determine the minimal important change (MIC) and meaningful change value (MCV) of the Disease Activity Index for Psoriatic Arthritis (DAPSA) and the effect size (ES) of DAPSA. METHODS: This was a retrospective cohort study, recruiting 106 patients who agreed to participate in the research from the Department of Dermatology, Xiangya Hospital, between November 1, 2019, and April 1, 2023. An anchor-based method using linear regression analyses was used to determine the MICs and MCVs of the DAPSA. The anchor question assessed whether the patient's well-being had changed since their previous visit, employing a 5-point Likert scale that ranged from "much improved" to "much deteriorated." RESULTS: The overall MIC value was 8.4 (95% CI 0.01-16.75). The MIC improvement was 9.5 (95% CI 0.89-18.14) and MIC deterioration was 1.1 (95% CI -9.81 to 12.05). The overall MCV was 10.5 (95% CI 4.34-16.72). MCV improvement was 11.4 (95% CI 5.95-16.95) and MCV deterioration was 1.1 (95% CI -9.81 to 12.05). The ES was 0.6. CONCLUSION: A change in DAPSA of 8.4 is indicative of an MIC, offering physicians an additional means to contextualize the patient's perception of disease activity during treatment, and a change in DAPSA of 10.5 is likely to be regarded as MCV. These values can enhance the utility of DAPSA in psoriatic arthritis clinical trials.


Assuntos
Artrite Psoriásica , Índice de Gravidade de Doença , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artrite Psoriásica/diagnóstico , China , População do Leste Asiático , Estudos Longitudinais , Diferença Mínima Clinicamente Importante , Estudos Retrospectivos
8.
J Dermatolog Treat ; 35(1): 2331782, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38513258

RESUMO

BACKGROUND: Data on the characteristics and treatment outcomes of super-responders and non-super-responders in psoriasis under adalimumab treatment are limited. METHODS: A retrospective analysis from psoriatic patients treated with adalimumab was compared to characterize super-responders vs non-super-responders' groups, identify factors associated with super response, and assess treatment outcomes after switching. RESULTS: 15 out of 70 (21.4%) patients were categorized as super-responder. The proportion of patients achieving a PASI 100 response was significantly higher in super-responders than non-super-responders at weeks 12, 24, and 52. Female sex and Charlson Co-morbidity Index were significantly associated with super-responders. A high level of high-density lipoprotein was independently associated with PASI 90 response at weeks 24 and 52. Additionally, nearly 35%-43% of non-super-responders switching to interleukin-17A (IL-17A) inhibitors may achieve a PASI 100 response at week 12. In contrast, all super-responders switching to IL-17A inhibitors achieved a PASI 100 response at week 4. CONCLUSIONS: Super-responders treated with adalimumab have a higher rate of being female and fewer comorbidities. And super-responders have better PASI responses than non-super-responders, whether the patients were treated with adalimumab or switched to IL-17A inhibitors.


Assuntos
Interleucina-17 , Psoríase , Humanos , Feminino , Masculino , Adalimumab/uso terapêutico , Estudos de Coortes , Estudos Retrospectivos , Resultado do Tratamento , Psoríase/tratamento farmacológico , Psoríase/induzido quimicamente , Inibidores de Interleucina , Índice de Gravidade de Doença
9.
Proc Natl Acad Sci U S A ; 121(4): e2317058121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38232281

RESUMO

Integration of methanogenic archaea with photocatalysts presents a sustainable solution for solar-driven methanogenesis. However, maximizing CH4 conversion efficiency remains challenging due to the intrinsic energy conservation and strictly restricted substrates of methanogenic archaea. Here, we report a solar-driven biotic-abiotic hybrid (biohybrid) system by incorporating cadmium sulfide (CdS) nanoparticles with a rationally designed methanogenic archaeon Methanosarcina acetivorans C2A, in which the glucose synergist protein and glucose kinase, an energy-efficient route for glucose transport and phosphorylation from Zymomonas mobilis, were implemented to facilitate nonnative substrate glucose for methanogenesis. We demonstrate that the photo-excited electrons facilitate membrane-bound electron transport chain, thereby augmenting the Na+ and H+ ion gradients across membrane to enhance adenosine triphosphate (ATP) synthesis. Additionally, this biohybrid system promotes the metabolism of pyruvate to acetyl coenzyme A (AcCoA) and inhibits the flow of AcCoA to the tricarboxylic acid (TCA) cycle, resulting in a 1.26-fold augmentation in CH4 production from glucose-derived carbon. Our results provide a unique strategy for enhancing methanogenesis through rational biohybrid design and reprogramming, which gives a promising avenue for sustainably manufacturing value-added chemicals.


Assuntos
Trifosfato de Adenosina , Metano , Metano/metabolismo , Transporte de Elétrons , Trifosfato de Adenosina/metabolismo , Metabolismo Energético , Transporte Biológico , Methanosarcina/metabolismo
10.
Plant Dis ; 108(3): 599-607, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37682223

RESUMO

Walnut is cultivated around the world for its precious woody nut and edible oil. Recently, walnut infected by Colletotrichum spp. resulted in a great yield and quality loss. In August and September 2014, walnut fruits with anthracnose were sampled from two commercial orchards in Shaanxi and Liaoning provinces, and five representative isolates were used in this study. To identify the pathogen properly, four genes per region (internal transcribed spacer, glyceraldehyde-3-phosphate dehydrogenase, actin, and chitin synthase) were sequenced and used in phylogenetic studies. Based on multilocus phylogenetic analysis, five isolates clustered with Colletotrichum fioriniae, including its ex-type, with 100% bootstrap support. The results of multilocus phylogenetic analyses, morphology, and pathogenicity confirmed that C. fioriniae was one of the walnut anthracnose pathogens in China. All 13 fungicides tested inhibited mycelial growth and spore germination. Flusilazole, fluazinam, prochloraz, and pyraclostrobin showed the strongest suppressive effects on the mycelial growth than the others, the average EC50 values ranged from 0.09 to 0.40 µg/ml, and there was not any significant difference (P < 0.05). Pyraclostrobin, thiram, and azoxystrobin were the most effective fungicides on spore germination (P < 0.05), and the EC50 values ranged from 0.01 to 0.44 µg/ml. Pyraclostrobin, azoxystrobin, fluazinam, flusilazole, mancozeb, thiram, and prochloraz exhibited a good control effect on walnut anthracnose caused by C. fioriniae, and preventive activities were greater than curative activities. Pyraclostrobin at 250 a.i. µg/ml and fluazinam at 500 a.i. µg/ml provided the highest preventive and curative efficacy, and the values ranged from 81.3 to 82.2% and from 72.9 to 73.6%, respectively. As a consequence, mancozeb and thiram could be used at the preinfection stage, and pyraclostrobin, azoxystrobin, flusilazole, fluazinam, and prochloraz could be used at the early stage for effective prevention and control of walnut anthracnose caused by C. fioriniae. The results will provide more significant instructions for controlling the disease effectively in northern China.


Assuntos
Aminopiridinas , Fungicidas Industriais , Juglans , Maneb , Pirimidinas , Silanos , Estrobilurinas , Triazóis , Zineb , Fungicidas Industriais/farmacologia , Nozes , Tiram , Filogenia , China
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