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1.
Carbohydr Polym ; 337: 122088, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710544

RESUMO

The construction of the preferred orientation structure by stretching is an efficient strategy to fabricate high-performance cellulose film and it is still an open issue whether crystalline structure or amorphous molecular chain is the key factor in determining the enhanced mechanical performance. Herein, uniaxial stretching with constant width followed by drying in a stretching state was carried out to cellulose hydrogels with physical and chemical double cross-linking networks, achieving high-performance regenerated cellulose films (RCFs) with an impressive tensile strength of 154.5 MPa and an elastic modulus of 5.4 GPa. The hierarchical structure of RCFs during uniaxial stretching and drying was systematically characterized from micro- to nanoscale, including microscopic morphology, crystalline structure as well as relaxation behavior at a molecular level. The two-dimensional correlation spectra of dynamic mechanical analysis and Havriliak-Negami fitting results verified that the enhanced mechanical properties of RCFs were mainly attributed to the stretch-induced tight packing and restricted relaxation of amorphous molecular chains. The new insight concerning the contribution of molecular chains in the amorphous region to the enhancement of mechanical performance for RCFs is expected to provide valuable guidance for designing and fabricating high-performance eco-friendly cellulose-based films.

2.
J Reconstr Microsurg ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38782030

RESUMO

BACKGROUND: Random flaps are the most used defect repair method for head and neck tumors and trauma plastic surgery. The distal part of the flap often undergoes oxidative stress (OS), ultimately leading to flap necrosis. Stem cells exosomes exhibit potential effects related to anti-inflammatory, regenerative, and antioxidant properties. Nuclear factor erythroid-2-related factor 2 (Nrf2) is an important factor in regulating oxidative balance. Exosomes have been reported to monitor its transcription to alleviate OS. This study examined the impacts and underlying mechanisms of antioxidant actions of exosomes derived from bone marrow mesenchymal stem cells (BMSCs-Exo) on random flaps. METHODS: BMSCs-Exo was injected into the tail veins of rats on days 0, 1, and 2 after surgery of random flaps. The rats were euthanized on day 3 to calculate the survival rate. Immunohistochemical staining, western blotting, dihydroethidium probe, superoxide dismutase, and malondialdehyde assay kits were used to detect OS level. Human umbilical vein endothelial cells were co-cultured with BMSCs-Exo and ML385 (an inhibitor of Nrf2) in vitro. RESULTS: BMSCs-Exo may significantly improve the survival rate of the random flaps by reducing apoptosis, inflammation, and OS while increasing angiogenesis. Besides, BMSCs-Exo can also increase mitochondrial membrane potential and reduce reactive oxygen species levels in vitro. These therapeutic effects might stem from the activation of the Keap1/Nrf2 signaling pathway. CONCLUSION: BMSCs-Exo improved the tissue antioxidant capacity by regulating the keap1/Nrf2 signaling pathway. BMSCs-Exo may be a new strategy to solve the problem of random flap necrosis.

3.
PLoS One ; 19(5): e0300833, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38820376

RESUMO

The invasive black tiger shrimp has caused serious ecological problems in the America. However, since it can be directly eaten or made into feed, it may be beneficial to other countries. In order to ensure ecological security, it is necessary to control the invasion of the black tiger shrimp through international cooperation. Common control modes of the black tiger shrimp include the introducing natural enemy mode, making feed mode and the "bringing to the table" mode. In order to derive the applicable scope of various control modes of the black tiger shrimp and provide suggestions for the security and sustainability of the ecological supply chain of the America and cooperative country, this article constructs three differential game models and compares and analyzes the equilibrium results obtained by the models. Finally, the study shows that the higher the price of feed and the price of black tiger shrimp, the greater the degree of control of the black tiger shrimp. If the price of the black tiger shrimp and the reputation of the America for controlling the black tiger shrimp are lower, the America can gain more benefits under the feed production mode. Otherwise, the America prefers to sell the black tiger shrimp directly, thus directly "bringing to the table". Compared with the feed production or "bringing to the table" mode, cooperative country prefer to control the black tiger shrimp flooding through the natural enemy introduction mode.


Assuntos
Cooperação Internacional , Espécies Introduzidas , Animais , Penaeidae
4.
Front Bioeng Biotechnol ; 12: 1380213, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585712

RESUMO

Microbially Induced Calcite Precipitation (MICP) represents an environmentally friendly and innovative soil grouting technology. Involving intricate biochemical processes, it poses challenges for a thorough investigation of factors influencing microbial grouting effectiveness through experimentation alone. Consequently, A three-dimensional numerical model was developed to predict the permeability of bio-grouting in porous media. The numerical model is validated by comparing its results with test results available in the literature. The validated model is then used to investigate the effects of variation bacterial solution concentration, cementation solution concentration, grouting rate and grouting time on grouting effectiveness. It was founded that the remediation effect was positively correlated with the bacterial solution concentration and the number of grouting. An increased grouting rate enhanced the transport efficiency of reactants. Additionally, the concentration of cementation solution exhibited no significant effect on the reduction of calcium carbonate yield and permeability.

5.
Int J Biol Macromol ; 266(Pt 2): 131425, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583830

RESUMO

Nano-MoS2 exhibit oxidoreductase-like activities, and has been shown to effectively eliminate excessive intracellular ROS and inhibit Aß aggregation, thus demonstrating promising potential for anti-Alzheimer's disease (anti-AD) intervention. However, the low water dispersibility and high toxicity of nano-MoS2 limits its further application. In this study, we developed a chondroitin sulphate (CS)-modified MoS2 nanoenzyme (CS@MoS2) by harnessing the excellent biocompatibility of CS and the exceptional activities of nano-MoS2 to explore its potential in anti-AD research. Promisingly, CS@MoS2 significantly inhibited Aß1-40 aggregation and prevented toxic injury in SH-SY5Y cells caused by Aß1-40. In addition, CS@MoS2 protected these cells from oxidative stress damage by regulating ROS production, as well as promoting the activities of SOD and GSH-Px. CS@MoS2 also modulated the intracellular Ca2+ imbalance and downregulated Tau hyperphosphorylation by activating GSK-3ß. CS@MoS2 suppressed p-NF-κB (p65) translocation to the nucleus by inhibiting MAPK phosphorylation, and modulated the expression of downstream anti- and proinflammatory cytokines. Owing to its multifunctional activities, CS@MoS2 effectively improved spatial learning, memory, and anxiety in D-gal/AlCl3-induced AD mice. Taken together, these results indicate that CS@MoS2 has significant potential for improving the therapeutic efficacy of the prevention and treatment of AD, while also presenting a novel framework for the application of nanoenzymes.


Assuntos
Doença de Alzheimer , Sulfatos de Condroitina , Dissulfetos , Molibdênio , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Sulfatos de Condroitina/química , Sulfatos de Condroitina/farmacologia , Animais , Camundongos , Humanos , Molibdênio/química , Molibdênio/farmacologia , Dissulfetos/química , Dissulfetos/farmacologia , Peptídeos beta-Amiloides/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Linhagem Celular Tumoral , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Masculino , Modelos Animais de Doenças
6.
Int J Biol Macromol ; 264(Pt 1): 130270, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423423

RESUMO

Fire alarm systems are essential for protecting lives and properties from fire hazards. However, most of the existing fire alarm nanopapers rely on the resistance reduction after heating, which requires direct contact with the flame. In this study, we present a novel fire alarm nanopaper (CMPA) based on heat-triggered shape recovery. The CMPA is composed of hydroxypropyl methyl cellulose (HPMC) as the matrix and 2D nanomaterials M(OH)(OCH3) as fillers. When the temperature of CMPA exceeded the glass transition, the thrice-folded CMPA-1.0 flattened in 30s and connected to the alarm circuit based on its conductive surface. According to the results, the CMPA-1.0 with a thickness of about 0.2 mm had an efficient electromagnetic shielding of 42.1 dB. Moreover, the CMPA-1.0 self-extinguished rapidly after being ignited with its original shape preserved. The peak heat release rate of CMPA-1.0 was 108.9 W/g, which was 61.9 % lower than that of HPMC. Furthermore, the thermal conductivity of CMPA-1.0 reached to 0.317 W m-1 K-1, which was 40.8 % higher than that of HPMC, reducing the heat accumulation effectively. This work shows that CMPA is an ideal material for sensitive and safe early fire alarm, and the strategy based on heat-triggered shape recovery is promising in fire alarm application.


Assuntos
Celulose , Retardadores de Chama , Temperatura Alta , Dopamina , Derivados da Hipromelose
7.
Int J Biol Macromol ; 263(Pt 2): 130379, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403214

RESUMO

Cytoplasmic coat protein complex II (COPII) plays a multifunctional role in the transport of newly synthesized proteins, autophagosome formation, and endoplasmic reticulum (ER)-ER-phagy. However, the molecular mechanisms of the COPII subunit in ER-phagy in plant pathogens remain unknown. Here, we identified the subunit of COPII vesicles (BcSfb3) and explored the importance of BcSfb3 in Botrytis cinerea. BcSfb3 deletion affected vegetative growth, conidiation, conidial morphology, and plasma membrane integrity. We confirmed that the increase in infectious hyphal growth was delayed in the ΔBcSfb3 mutant, reducing its pathogenicity in the host plant. Furthermore, the ΔBcSfb3 mutant was sensitive to ER stress, which caused massive ER expansion and induced the formation of ER whorls that were taken up into the vacuole. Further examination demonstrated that BcSfb3 deletion caused ER stress initiated by unfolded protein response, and which led to the promotion of ER-phagy and autophagy that participate in sclerotia formation. In conclusion, these results demonstrate that BcSfb3 plays an important role in fungal development, pathogenesis, ER-phagy and autophagy in B. cinerea.


Assuntos
Autofagia , Retículo Endoplasmático , Virulência , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Botrytis
8.
Glob Chang Biol ; 30(1): e17141, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273520

RESUMO

Droughts have been implicated as the main driver behind recent vegetation die-off and are projected to drive greater mortality under future climate change. Understanding the coupling relationship between vegetation and drought has been of great global interest. Currently, the coupling relationship between vegetation and drought is mainly evaluated by correlation coefficients or regression slopes. However, the optimal drought timescale of vegetation response to drought, as a key indicator reflecting vegetation sensitivity to drought, has largely been ignored. Here, we apply the optimal drought timescale identification method to examine the change in coupling between vegetation and drought over the past three decades (1982-2015) with long-term satellite-derived Normalized Difference Vegetation Index and Standardized Precipitation-Evapotranspiration Index data. We find substantial increasing response of vegetation to drought timescales globally, and the correlation coefficient between vegetation and drought under optimal drought timescale overall declines between 1982 and 2015. This decrease in vegetation-drought coupling is mainly observed in regions with water deficit, although its initial correlation is relatively high. However, vegetation in water-surplus regions, with low coupling in earlier stages, is prone to show an increasing trend. The observed changes may be driven by the increasing trend of atmospheric CO2 . Our findings highlight more pressing drought risk in water-surplus regions than in water-deficit regions, which advances our understanding of the long-term vegetation-drought relationship and provides essential insights for mapping future vegetation sensitivity to drought under changing climate conditions.


Assuntos
Mudança Climática , Secas , Água , Ecossistema , China
9.
BMJ ; 384: e076410, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38286487

RESUMO

OBJECTIVE: To evaluate the comparative efficacy and safety of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on glycaemic control, body weight, and lipid profile in adults with type 2 diabetes. DESIGN: Systematic review and network meta-analysis. DATA SOURCES: PubMed, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), and Embase from database inception to 19 August 2023. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Eligible randomised controlled trials enrolled adults with type 2 diabetes who received GLP-1RA treatments and compared effects with placebo or any GLP-1RA drug, with a follow-up duration of at least 12 weeks. Trials with a crossover design, non-inferiority studies comparing GLP-1RA and other drug classes without a placebo group, using withdrawn drugs, and non-English studies were deemed ineligible. RESULTS: 76 eligible trials involving 15 GLP-1RA drugs and 39 246 participants were included in this network meta-analysis; all subsequent estimates refer to the comparison with placebo. All 15 GLP-1RAs effectively lowered haemoglobin A1c and fasting plasma glucose concentrations. Tirzepatide induced the largest reduction of haemoglobin A1c concentrations (mean difference -2.10% (95% confidence interval -2.47% to -1.74%), surface under the cumulative ranking curve 94.2%; high confidence of evidence), and fasting plasma glucose concentrations (-3.12 mmol/L (-3.59 to -2.66), 97.2%; high confidence), and proved the most effective GLP-1RA drug for glycaemic control. Furthermore, GLP-1RAs were shown to have strong benefits to weight management for patients with type 2 diabetes. CagriSema (semaglutide with cagrilintide) resulted in the highest weight loss (mean difference -14.03 kg (95% confidence interval -17.05 to -11.00); high confidence of evidence), followed by tirzepatide (-8.47 kg (-9.68 to -7.26); high confidence). Semaglutide was effective in lowering the concentration of low density lipoprotein (-0.16 mmol/L (-0.30 to -0.02)) and total cholesterol (-0.48 mmol/L (-0.84 to -0.11)). Moreover, this study also raises awareness of gastrointestinal adverse events induced by GLP-1RAs, and concerns about safety are especially warranted for high dose administration. CONCLUSIONS: GLP-1RAs are efficacious in treating adults with type 2 diabetes. Compared with the placebo, tirzepatide was the most effective GLP-1RA drug for glycaemic control by reducing haemoglobin A1c and fasting plasma glucose concentrations. GLP-1RAs also significantly improved weight management for type 2 diabetes, with CagriSema performing the best for weight loss. The results prompt safety concerns for GLP-1RAs, especially with high dose administration, regarding gastrointestinal adverse events. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022342845.


Assuntos
Diabetes Mellitus Tipo 2 , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon , Adulto , Humanos , Glicemia , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Hemoglobinas Glicadas , Controle Glicêmico/métodos , Hipoglicemiantes/efeitos adversos , Metanálise em Rede , Redução de Peso , Metabolismo dos Lipídeos/efeitos dos fármacos
10.
Int J Biol Macromol ; 261(Pt 2): 129829, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38296134

RESUMO

Three-dimensional interpenetrating and hierarchically porous carbon material is an efficient catalyst support in water remediation and it is still a daunting challenge to establish the relationship between hierarchically porous structure and catalytic degradation performance. Herein, a highly porous silica (SiO2)/cellulose-based carbon aerogel with iron-based catalyst (FexOy) was fabricated by in-situ synthesis, freeze-drying and pyrolysis, where the addition of SiO2 induced the hierarchically porous morphology and three-dimensional interpenetrating sheet-like network with nitrogen doping. The destruction of cellulose crystalline structure by SiO2 and the iron-catalyzed breakdown of glycosidic bonds synergistically facilitated the formation of electron-rich graphite-like carbon skeleton. The unique microstructure is confirmed to be favorable for the diffusion of reactants and electron transport during catalytic process, thus boosting the catalytic degradation performance of carbon aerogels. As a result, the catalytic degradation efficiency of tetracycline under light irradiation by adding only 5 mg of FexOy/SiO2 cellulose carbon aerogels was as high as 90 % within 60 min, demonstrating the synergistic effect of photocatalysis and Fenton reaction. This ingenious structure design provides new insight into the relationship between hierarchically porous structure of carbon aerogels and their catalytic degradation performance, and opens a new avenue to develop cellulose-based carbon aerogel catalysts with efficient catalytic performance.


Assuntos
Carbono , Compostos Heterocíclicos , Carbono/química , Ferro/química , Dióxido de Silício , Celulose/química , Porosidade , Tetraciclina/química , Antibacterianos , Catálise
11.
J Cell Physiol ; 238(12): 2855-2866, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37942811

RESUMO

The regulatory network between signaling pathways and transcription factors (TFs) is crucial for the maintenance of pluripotent stem cells. However, little is known about how the key TF OCT4 coordinates signaling pathways to regulate self-renewal and lineage differentiation of porcine pluripotent stem cells (pPSCs). Here, we explored the function of OCT4 in pPSCs by transcriptome and chromatin accessibility analysis. The TFs motif enrichment analysis revealed that, following OCT4 knockdown, the regions of increased chromatin accessibility were enriched with EOMES, GATA6, and FOXA1, indicating that pPSCs differentiated toward the mesoendoderm (ME) lineage. Besides, pPSCs rapidly differentiated into ME when the WNT/ß-catenin inhibitor XAV939 was removed. However, the ME differentiation of pPSCs caused by OCT4 knockdown did not rely on the activation of WNT/ß-catenin signaling because the target gene of WNT/ß-catenin signaling, AXIN2 was not upregulated after OCT4 knockdown, despite significant upregulation of WLS and some WNT ligands. Importantly, OCT4 is directly bound to the promoter and enhancers of EOMES and repressed its transcription. Overexpression of EOMES was sufficient to induce ME differentiation in the presence of XAV939. These results demonstrate that OCT4 can regulate WNT/ß-catenin signaling and prevent ME differentiation of pPSCs by repressing EOMES transcription.


Assuntos
Diferenciação Celular , Células-Tronco Pluripotentes , Via de Sinalização Wnt , Animais , beta Catenina/genética , beta Catenina/metabolismo , Diferenciação Celular/genética , Cromatina/metabolismo , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Suínos , Via de Sinalização Wnt/genética , Proteínas com Domínio T/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Linhagem Celular
12.
Front Immunol ; 14: 1264705, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37954613

RESUMO

Background: Inflammatory bowel disease (IBD) has caused severe health concerns worldwide. Studies on gut microbiota have provided new targets for preventing and treating IBD. Therefore, it is essential to have a comprehensive understanding of the current status and evolution of gut microbiota and IBD studies. Methods: A bibliometric analysis was performed on documents during 2003-2022 retrieved from the Scopus database, including bibliographical profiles, citation patterns, and collaboration details. Software programs of VOSviewer, CiteSpace, and the Bibliometrix R package visually displayed the mass data presented in the scientific landscapes and networks. Results: 10479 publications were retrieved, showing a steadily growing tendency in interest. Xavier Ramnik J. group led the total number of publications (73 papers) and 19787 citations, whose productive work aroused widespread concern. Among the 1977 academic journals, the most prolific ones were Inflammatory Bowel Diseases, Frontiers in Immunology, and Nutrients. Research outputs from the United States (US, 9196 publications), China (5587), and Italy (2305) were highly ranked. Conclusion: Our bibliometric study revealed that the role of gut microbiota has become a hot topic of IBD research worldwide. These findings are expected to improve understanding of research characteristics and to guide future directions in this field.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Humanos , Bibliometria , China , Bases de Dados Factuais
13.
J Thorac Dis ; 15(8): 4486-4496, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37691663

RESUMO

Background: Early cardiopulmonary exercise test (CPET) may predict the prognosis of patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI). However, data from CPET to assess the exercise capacity of patients with AMI PCI are still scarce. This study aimed to evaluate the safety of the CPET and assess the predictors and clinical influence of exercise capacity measured by CPET in patients with AMI within 1 week after PCI. Methods: A total of 275 patients with AMI who underwent PCI in the acute phase were selected. Reduced exercise capacity was defined as peak oxygen uptake (VO2peak) <16 mL/kg/min. According to VO2peak, patients were divided into a normal exercise tolerance group and a reduced exercise tolerance group. The general clinical conditions were compared between the 2 groups to investigate the safety of CPET and the influencing factors of exercise tolerance. A nomogram model for predicting patients' exercise capacity was further developed. Clinical outcomes were recorded. Results: The median time of CPET in all patients was 5 days after PCI. Among the 275 patients, exercise tolerance decreased in 90 cases (32.72%). Multivariate logic analysis showed that E/e', age, glycosylated hemoglobin, and estimated glomerular filtration rate (eGFR) were independent predictors of early exercise capacity reduction in these patients. Utilizing the correlation coefficients from pre-assessment clinical and CPET indicators within the logistic regression framework, we constructed a nomogram model to forecast the diminishing exercise tolerance in AMI patients. The predictive accuracy of this model, as indicated by a C-index of 0.771 and an area under the receiver operating characteristic (ROC) curve of 0.771 (95% CI: 0.710-0.832), demonstrates its potential as a robust tool in clinical settings. During a follow-up of 24 months, the incidence of clinical outcomes in patients with low exercise tolerance was significantly higher than that in patients with normal exercise tolerance, among which all-cause mortality and reinfarction were statistically different (P=0.009 and P=0.043). Conclusions: The reduced exercise capacity in patients with AMI after initial PCI is related to age, diastolic dysfunction, renal function, and blood glucose control, which may lead to poor clinical prognosis. The nomogram prediction model performed well in predicting the declining exercise tolerance of patients with AMI.

14.
Oral Dis ; 2023 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-37455401

RESUMO

BACKGROUND: The aim of this study was to determine the significance of elective neck dissection (END) for patients of different ages with T2N0M0 oral squamous cell carcinoma (OSCC) and sought to analyze the reasons behind it and its value for clinical guidance. METHODS: This study enrolled 391 patients with T2N0M0 OSCC who were surgically treated in our hospital and were divided into young-, moderate-, and advanced-age groups according to our previous study. The Chi-square test and Kaplan-Meier analysis were performed for statistical analysis. RESULTS: Compared with moderate- and advanced-age patients, young patients with T2N0M0 OSCC had higher lymph node metastasis rates and lymph node ratios. Therefore, END significantly improved the recurrence (p = 0.001) and survival (p = 0.001) for young patients, but not for moderate-age patients. Advanced-age patients even benefit from watchful waiting. END significantly improved recurrence and survival in young patients with smoking or alcohol consumption habits. CONCLUSIONS: END improved the prognosis of young patients, and it was related to their higher metastasis rate. However, advanced-age patients benefited from the wait-and-see policy. END is essential for the young patients with smoking or drinking habit, it is also highly recommended for nonsmokers and nondrinkers.

15.
ACS Macro Lett ; 12(7): 880-887, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37343235

RESUMO

Cellulose-based dielectrics with attractive dielectric performance are promising candidates to develop eco-friendly electrostatic energy storage devices. Herein, all-cellulose composite films with superior dielectric constant were fabricated by manipulating the dissolution temperature of native cellulose, where we revealed the relationship among the hierarchical microstructure of the crystalline structure, the hydrogen bonding network, the relaxation behavior at a molecular level, and the dielectric performance of the cellulose film. The coexistence of cellulose I and cellulose II led to a weakened hydrogen bonding network and unstable C6 conformations. The increased mobility of cellulose chains in the cellulose I-amorphous interphase enhanced the dielectric relaxation strength of side groups and localized main chains. As a result, the as-prepared all-cellulose composite films exhibited a fascinating dielectric constant of as high as 13.9 at 1000 Hz. This work proposed here provides a significant step toward fundamentally understanding the dielectric relaxation of cellulose, thus developing high-performance and eco-friendly cellulose-based film capacitors.

16.
Microbiol Spectr ; 11(3): e0052623, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37191530

RESUMO

Botrytis cinerea, the causal agent of gray mold, is an important plant pathogen causing preharvest and postharvest diseases. Due to the extensive use of commercial fungicides, fungicide-resistant strains have emerged. Natural compounds with antifungal properties are widely present in various kinds of organisms. Perillaldehyde (PA), derived from the plant species Perilla frutescens, is generally recognized as a potent antimicrobial substance and to be safe to humans and the environment. In this study, we demonstrated that PA could significantly inhibit the mycelial growth of B. cinerea and reduced its pathogenicity on tomato leaves. We also found that PA had a significant protective effect on tomato, grape, and strawberry. The antifungal mechanism of PA was investigated by measuring the reactive oxygen species (ROS) accumulation, the intracellular Ca2+ level, the mitochondrial membrane potential, DNA fragmentation, and phosphatidylserine exposure. Further analyses revealed that PA promoted protein ubiquitination and induced autophagic activities and then triggered protein degradation. When the two metacaspase genes, BcMca1 and BcMca2, were knocked out from B. cinerea, all mutants did not exhibit reduced sensitivity to PA. These findings demonstrated that PA could induce metacaspase-independent apoptosis in B. cinerea. Based on our results, we proposed that PA could be used as an effective control agent for gray mold management. IMPORTANCE Botrytis cinerea causes gray mold disease, is considered one of the most important dangerous pathogens worldwide, and leads to severe economic losses worldwide. Due to the lack of resistant varieties of B. cinerea, gray mold control has mainly relied on application of synthetic fungicides. However, long-term and extensive use of synthetic fungicides has increased fungicide resistance in B. cinerea and is harmful to humans and the environment. In this study, we found that perillaldehyde has a significant protective effect on tomato, grape, and strawberry. We further characterized the antifungal mechanism of PA on B. cinerea. Our results indicated that PA induced apoptosis that was independent of metacaspase function.


Assuntos
Fungicidas Industriais , Solanum lycopersicum , Humanos , Antifúngicos/farmacologia , Fungicidas Industriais/farmacologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Apoptose
17.
Front Immunol ; 14: 1143548, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168869

RESUMO

Background: Probiotics play a vital role in treating immune and inflammatory diseases by improving intestinal barrier function; however, a comprehensive evaluation is missing. The present study aimed to explore the impact of probiotics on the intestinal barrier and related immune function, inflammation, and microbiota composition. A systematic review and meta-analyses were conducted. Methods: Four major databases (PubMed, Science Citation Index Expanded, CENTRAL, and Embase) were thoroughly searched. Weighted mean differences were calculated for continuous outcomes with corresponding 95% confidence intervals (CIs), heterogeneity among studies was evaluated utilizing I2 statistic (Chi-Square test), and data were pooled using random effects meta-analyses. Results: Meta-analysis of data from a total of 26 RCTs (n = 1891) indicated that probiotics significantly improved gut barrier function measured by levels of TER (MD, 5.27, 95% CI, 3.82 to 6.72, P < 0.00001), serum zonulin (SMD, -1.58, 95% CI, -2.49 to -0.66, P = 0.0007), endotoxin (SMD, -3.20, 95% CI, -5.41 to -0.98, P = 0.005), and LPS (SMD, -0.47, 95% CI, -0.85 to -0.09, P = 0.02). Furthermore, probiotic groups demonstrated better efficacy over control groups in reducing inflammatory factors, including CRP, TNF-α, and IL-6. Probiotics can also modulate the gut microbiota structure by boosting the enrichment of Bifidobacterium and Lactobacillus. Conclusion: The present work revealed that probiotics could improve intestinal barrier function, and alleviate inflammation and microbial dysbiosis. Further high-quality RCTs are warranted to achieve a more definitive conclusion. Clinical trial registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=281822, identifier CRD42021281822.


Assuntos
Microbioma Gastrointestinal , Probióticos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Probióticos/uso terapêutico , Inflamação , Bifidobacterium
18.
ACS Appl Mater Interfaces ; 15(19): 23701-23710, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37140941

RESUMO

Polypropylene (PP) serves as an excellent commercialized polymer dielectric film owing to its high breakdown strength, excellent self-healing ability, and flexibility. However, its low dielectric constant causes the large volume of the capacitor. Constructing multicomponent polypropylene-based all-organic polymer dielectric films is a facile strategy for achieving high energy density and efficiency simultaneously. Thereinto, the interfaces between the components become the key factors that determine the energy storage performance of the dielectric films. In this work, we propose to fabricate high-performance polyamide 513 (PA513)/PP all-organic polymer dielectric films via the construction of abundant well-aligned and isolated nanofibrillar interfaces. Laudably, a significant enhancement in the breakdown strength is achieved from 573.1 MV/m of pure PP to 692.3 MV/m with 5 wt % of PA513 nanofibrils. Besides, a maximum discharge energy density of about 4.4 J/cm2 is realized with 20 wt % of PA513 nanofibrils, which is about 1.6-folds higher than pure PP. Simultaneously, the energy efficiency of samples with modulated interfaces maintains higher than 80% up to 600 MV/m, which is much higher than pure PP of about 40.7% at 550 MV/m. This work provides a new strategy to fabricate high-performance multicomponent all-organic polymer dielectric films on an industrial scale.

19.
Energy Econ ; 120: 106618, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36915626

RESUMO

Using U.S. data, we investigate how the COVID-19 pandemic influences oil price returns in an asset pricing framework. Unlike earlier studies, we consider a threshold model to allow for the possibility that COVID-19 risk may not play a role until it reaches a certain level. Based on WTI crude oil spot price data from January 2020 to December 2021, our findings show that oil returns significantly decline with the daily number of COVID-19 deaths but only if the daily death toll exceeds approximately 2100. In addition, a more severe COVID-19 pandemic can substantially increase the exposure of oil returns to various systematic risk factors, which has not been documented in previous literature.

20.
Am J Chin Med ; 51(3): 677-699, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36883990

RESUMO

Ulcerative colitis (UC) has become a global epidemic, and the lack of an effective cure highlights the necessity and urgency to explore novel therapies. Sijunzi Decoction (SJZD), a classical Chinese herbal formula, has been comprehensively applied and clinically proven effective in treating UC; however, the pharmacological mechanism behind its therapeutic benefits is largely obscure. Here, we find that SJZD can restore microbiota homeostasis and intestinal barrier integrity in DSS-induced colitis. SJZD significantly alleviated the colonic tissue damage and improved the goblet cell count, MUC2 secretion, and tight junction protein expressions, which indicated enhanced intestinal barrier integrity. SJZD remarkedly suppressed the abundance of phylum Proteobacteria and genus Escherichia-Shigella, which are typical features of microbial dysbiosis. Escherichia-Shigella was negatively correlated with body weight and colon length, and positively correlated with disease activity index and IL-1[Formula: see text]. Furthermore, through gut microbiota depletion, we confirmed that SJZD exerted anti-inflammatory activities in a gut microbiota-dependent manner, and fecal microbiota transplantation (FMT) validated the mediating role of gut microbiota in the SJZD treatment of UC. Through gut microbiota, SJZD modulates the biosynthesis of bile acids (BAs), especially tauroursodeoxycholic acid (TUDCA), which has been identified as the signature BA during SJZD treatment. Cumulatively, our findings disclose that SJZD attenuates UC via orchestrating gut homeostasis in microbial modulation and intestinal barrier integrity, thus offering a promising alternative approach to the clinical management of UC.


Assuntos
Colite Ulcerativa , Colite , Medicamentos de Ervas Chinesas , Panax , Animais , Camundongos , Colite Ulcerativa/tratamento farmacológico , Homeostase , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Colo , Sulfato de Dextrana , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
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