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1.
Front Chem ; 12: 1407667, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39296365

RESUMO

Introduction: The increasing prevalence of recurrent spontaneous abortion (RSA) poses significant physical and psychological challenges for affected individuals. Quercetin, a natural plant flavonoid, shows promise in reducing miscarriage rates, yet its precise mechanism remains elusive. This study uses network pharmacology, molecular docking, and experimental validation to explore the molecular pathways through which quercetin mitigates RSA. Methods: Quercetin-related target genes were sourced from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), and RSA target genes were retrieved from the Comparative Toxicogenomics Database (CTD), with overlapping targets identified using Venn diagrams. All genes were visualized using the STRING database, and core targets were selected with Cytoscape 3.7.3. Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted using the DAVID and Reactome online resources. Subsequently, HTR-8/SVneo cells were stimulated with lipopolysaccharide (LPS) and treated with varying concentrations of quercetin (1, 5, and 10 µM), then subjected to CCK-8, wound healing, transwell, and annexin V-FITC/PI apoptosis assays. Reverse-transcription quantitative PCR was used to determine the mRNA expression levels of IL-1ß, TNF-α, and IL-6 in LPS-induced cells post-quercetin intervention, and western blotting was used to measure AKT1, MMP9, and caspase-3 protein levels. Results: A total of 139 quercetin-associated target genes were identified from the TCMSP database, and 98 disease-associated target genes were obtained from the CTD, resulting in 25 shared target genes. Gene ontology enrichment highlighted the involvement of these targets in positive regulation of apoptosis, response to hypoxia, and intrinsic apoptotic signaling pathway in response to DNA damage. KEGG pathway analysis indicated enrichment in pathways related to interleukin-4 and interleukin-13 signaling, cytokine signaling in the immune system, and apoptosis. Molecular docking studies revealed robust binding of quercetin with MMP9, AKT1, IL-1ß, TNF, and caspase-3. In vitro experiments demonstrated that quercetin enhanced LPS-induced cell activity, fostering proliferation, migration, and invasion, and reducing apoptosis. Moreover, quercetin reduced IL-1ß, TNF-α, and IL-6 mRNA expression, increased AKT1 and MMP9 protein levels, and reduced caspase-3 expression. Conclusion: Quercetin could mitigate the incidence of RSA by modulating inflammatory responses and apoptotic processes, through upregulation of AKT1 and MMP9, and downregulation of caspase-3, IL-1ß, TNF-α, and IL-6. Quercetin opens up a new way of thinking about treating RSA.

2.
Microbiol Spectr ; : e0414623, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39162513

RESUMO

The management of Pseudomonas aeruginosa (P. aeruginosa) infections presents a substantial challenge to clinics and public health, emphasizing the urgent need for innovative strategies to address this issue. Quorum sensing (QS) is an intercellular communication mechanism that coordinates bacterial activities involved in various virulence mechanisms, such as acquiring host nutrients, facilitating biofilm formation, enhancing motility, secreting virulence factors, and evading host immune responses, all of which play a crucial role in the colonization and infection of P. aeruginosa. The LasI/R and RhlI/R sub-systems dominate in the QS system of P. aeruginosa. Macrophages play a pivotal role in the host's innate immune response to P. aeruginosa invasion, particularly through phagocytosis as the initial host defense mechanism. This study investigated the effects of P. aeruginosa's QS system on THP-1 macrophages. Mutants of PAO1 with lasI/rhlI deletion, as well as their corresponding complemented strains, were obtained, and significant downregulation of QS-related genes was observed in the mutants. Furthermore, the ΔlasI and ΔlasIΔrhlI mutants exhibited significantly attenuated virulence in terms of biofilm formation, extracellular polymeric substances synthesis, bacterial adhesion, motility, and virulence factors production. When infected with ΔlasI and ΔlasIΔrhlI mutants, THP-1 macrophages exhibited enhanced scavenging ability against the mutants and demonstrated resistance to cytotoxicity, oxidative stress, inflammatory response, and apoptosis induced by the culture supernatants of these mutant strains. These findings offer novel insights into the mechanisms underlying how the lasI/rhlI mutation attenuates cytotoxicity, oxidative stress, inflammation, and apoptosis in macrophages induced by P. aeruginosa.IMPORTANCEP. aeruginosa is classified as one of the ESKAPE pathogens and poses a global public health concern. The QS system of this versatile pathogen contributes to a broad spectrum of virulence, thereby constraining therapeutic options for serious infections. This study illustrated that the lasI/rhlI mutation of the QS system plays a prominent role in attenuating the virulence of P. aeruginosa by affecting bacterial adhesion, biofilm formation, extracellular polymeric substances synthesis, bacterial motility, and virulence factors' production. Notably, THP-1 macrophages infected with mutant strains exhibited increased phagocytic activity in eliminating intracellular bacteria and enhanced resistance to cytotoxicity, oxidative stress, inflammation, and apoptosis. These findings suggest that targeted intervention toward the QS system is anticipated to diminish the pathogenicity of P. aeruginosa to THP-1 macrophages.

3.
Kaohsiung J Med Sci ; 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39162596

RESUMO

Recurrent spontaneous abortion (RSA) has a complex pathogenesis with an increasing prevalence and is one of the most intractable clinical challenges in the field of reproductive medicine. Quercetin (QCT) is an effective active ingredient extracted from Semen Cuscutae and Herba Taxilli used in traditional Chinese medicine for tonifyng the kidneys and promoting fetal restoration. Although QCT helps improve adverse pregnancy outcomes, the specific mechanism remains unclear. The trophoblast cell line HTR-8/SVneo cultured in vitro was treated with different concentrations of QCT, and the cell counting kit-8 assay, wound healing assay, transwell assay, and western blotting were used to evaluate the effects and mechanisms of QCT on the proliferation, migration, and invasion of HTR-8/SVneo cells, respectively. To assess the expression levels of miR-149-3p and AKT serine/threonine kinase 1 (AKT1), quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting analysis were performed. A dual-luciferase reporter assay was used to investigate the potential regulatory relationship between miR-149-3p and AKT1. Our results showed that QCT promoted the proliferation, migration, and invasion of trophoblast cells, promoted the expression of MMP2, MMP9, and vimentin, and downregulated the expression of E-cadherin. Mechanistically, QCT downregulated the expression of miR-149-3p and upregulated the expression of AKT1, and miR-149-3p directly targets AKT1, negatively regulating its expression. Overexpression of miR-149-3p and silencing of AKT1 counteracted the promotional effects of QCT on trophoblast proliferation, migration, and invasion. Taken together, QCT regulates the migration and invasion abilities of HTR-8/SVneo cells through the miR-149-3p/AKT1 axis, which may provide a promising therapeutic approach for RSA.

4.
Small ; : e2404737, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39210644

RESUMO

With the increasing focus on triboelectric-based sensors, research on synthesizing dielectric layers from specific substances is gradually emerging. Despite numerous negatively-charged triboelectric materials, there is a scarcity of synthesizable positively-charged materials, creating a research gap. This study demonstrates the molecular design of a conjugated, mesoporous, self-assembled sheet via bottom-up synthesis. The synthesized sheet is functionalized to create a triboelectric nanogenerator. Its large specific surface area, softness, and internal space increase the actual contact area and provide adsorption sites for polypyrrole nanoparticles. The incorporation of -COO functional group enhances positive triboelectric performance, forming a dielectric layer with charge-trapping capabilities. When contact with polytetrafluoroethylene (PTFE), this structure boosts the output voltage, showing significant amplification after charge injection with minimal decay. As a demonstration, the bilayer structure is applied as a touchpad on the experimenter's arm to write symbols. The signals are input into an innovative machine-learning model to interpret the writer's intent. Additionally, the device connects to a terminal for real-time medical services, suggesting practical applications for wearable triboelectric sensors with artificial intelligence.

5.
Molecules ; 29(16)2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39202892

RESUMO

A series of Zr-TiO2 catalysts were prepared using a facile sol-gel method and were used for N-methylmorpholine (NMM) oxidation to N-methylmorpholine-N-oxide (NMMO). The structure features of Zr-TiO2 catalysts were studied in detail through a variety of characterization methods, such as XRD, SEM, N2 adsorption-desorption isotherms, XPS, EPR, and O2-TPD. As-obtained 5%Zr-TiO2 catalysts had superior catalytic performance and stability with a 97.6% NMMO yield at 40 °C, which related to Zr doping, a higher surface area, more oxygen vacancies, and oxygen chemisorption on the catalytic surface. This work provides an efficient preparation strategy of TiO2-based catalysts for selective oxidation reactions by a facile method.

6.
J Nanobiotechnology ; 22(1): 307, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38825668

RESUMO

Skin aging is characterized by the disruption of skin homeostasis and impaired skin injury repair. Treatment of aging skin has long been limited by the unclear intervention targets and delivery techniques. Engineering extracellular vesicles (EVs) as an upgraded version of natural EVs holds great potential in regenerative medicine. In this study, we found that the expression of the critical antioxidant and detoxification gene Gstm2 was significantly reduced in aging skin. Thus, we constructed the skin primary fibroblasts-derived EVs encapsulating Gstm2 mRNA (EVsGstm2), and found that EVsGstm2 could significantly improve skin homeostasis and accelerate wound healing in aged mice. Mechanistically, we found that EVsGstm2 alleviated oxidative stress damage of aging dermal fibroblasts by modulating mitochondrial oxidative phosphorylation, and promoted dermal fibroblasts to regulate skin epidermal cell function by paracrine secretion of Nascent Polypeptide-Associated Complex Alpha subunit (NACA). Furthermore, we confirmed that NACA is a novel skin epidermal cell protective molecule that regulates skin epidermal cell turnover through the ROS-ERK-ETS-Cyclin D pathway. Our findings demonstrate the feasibility and efficacy of EVs-mediated delivery of Gstm2 for aged skin treatment and unveil novel roles of GSTM2 and NACA for improving aging skin.


Assuntos
Vesículas Extracelulares , Fibroblastos , Glutationa Transferase , RNA Mensageiro , Envelhecimento da Pele , Cicatrização , Animais , Camundongos , Fibroblastos/metabolismo , Glutationa Transferase/metabolismo , Vesículas Extracelulares/metabolismo , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Epiderme/metabolismo , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Pele/metabolismo , Masculino , Humanos , Células Epidérmicas/metabolismo , Células Cultivadas
7.
Artigo em Inglês | MEDLINE | ID: mdl-38814596

RESUMO

Background: Infectious bone defect refers to severe bone tissue damage caused by skeletal infection, often resulting in impaired skeletal function and intense inflammatory responses. Treating infectious bone defects is a challenging task, as conventional treatment methods often fail to completely eliminate the infection focus and may easily lead to inflammatory responses in the bone defect area. Objective: To examine the impacts of bone transport (BT) in conjunction with drug-loaded calcium sulfate (DLCS) on the expression of inflammatory factors and vascular endothelial growth factor (VEGF) in rats with infectious bone defects. Methods: A total of 40 rats were randomly allocated to 4 groups-the sham, model, BT, and BT + DLCS groups-with 10 rats in each group. Interleukin 10 (IL-10), tumor necrosis factor (TNF), nuclear factor-κB (NF-κB), insulinlike growth factor 1 (IGF 1), and recombinant human basic fibroblast growth factor (rhbFGF) concentrations in serum were measured using enzyme-linked immunosorbent assay. In bone tissue, histopathological changes in defective bone were assessed through hematoxylin-eosin staining, CD34 expression was examined by immunohistochemistry, and VEGF expression was examined by Western blot. Results: In comparison with the sham group, the model group had significant increases in serum IL-10, TNF, and NF-κB concentrations as well as notable decreases in IGF-1 and rhbFGF serum concentrations and CD34 and VEGF expression in the bone tissue (P < .05). In contrast to the model group, both the BT and BT + DLCS groups had significant reductions in serum concentrations of IL-10, TNF, and NF-κB. Additionally, the BT and BT + DLCS groups had significant increases in serum concentrations of IGF-1 and rhbFGF as well as expression of CD34 and VEGF in the bone tissue (P < .05). The BT + DLCS group had significantly lower serum concentrations of IL-10, TNF, and NF-κB compared with the BT group. Furthermore, the BT + DLCS group had significantly elevated serum concentrations of IGF-1 and rhbFGF as well as increased expression of CD34 and VEGF in the bone tissue compared with the BT group (P < .05). Conclusion: The promotion of infected bone defect healing in rats through the combination of BT and DLCS may be attributed to the suppression of inflammatory responses and the elevation of VEGF expression to facilitate vascular regeneration.

8.
Ecotoxicol Environ Saf ; 277: 116373, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38653023

RESUMO

Cr (VI) is extremely harmful to both the environment and human health, and it can linger in the environment for a very long period. In this research, the Leersia hexandra Swartz constructed wetland-microbial fuel cell (CW-MFC) system was constructed to purify Cr (VI) wastewater. By comparing with the constructed wetland (CW) system, the system electricity generation, pollutants removal, Cr enrichment, and morphological transformation of the system were discussed. The results demonstrated that the L. hexandra CW-MFC system promoted removal of pollutants and production of electricity of the system. The maximum voltage of the system was 499 mV, the COD and Cr (VI) removal efficiency was 93.73% and 97.00%. At the same time, it enhanced the substrate and L. hexandra ability to absorb Cr and change it morphologically transformation. Additionally, the results of XPS and XANES showed that the majority of the Cr in the L. hexandra and substrate was present as Cr (III). In the L. hexandra CW-MFC system, Geobacter also functioned as the primary metal catabolic reducing and electrogenic bacteria. As a result, L. hexandra CW-MFC system possesses the added benefit of removing Cr (VI) while producing energy compared to the traditional CW system.


Assuntos
Fontes de Energia Bioelétrica , Cromo , Águas Residuárias , Poluentes Químicos da Água , Áreas Alagadas , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Biodegradação Ambiental , Hydrocharitaceae , Geobacter/metabolismo , Eletricidade
9.
Med Sci Monit ; 30: e942626, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38525551

RESUMO

BACKGROUND This study aimed to evaluate the epidemiology of osteoarthritis in China in a comprehensive and reliable way, to project its future epidemiological patterns, and to mitigate its health hazards. MATERIAL AND METHODS Data were extracted and analyzed from the Global Burden of Diseases Study 2019. Trends in osteoarthritis epidemiology were explored using joinpoint regression analysis. Additionally, we analyzed dynamic trends using the sociodemographic index (SDI) of China. To assess and predict the epidemiology of osteoarthritis from 2020 to 2039, we used both the Bayesian age-period-cohort model and Nordpred model. RESULTS The number of prevalent cases, incident cases, and years lived with disability (YLDs) for osteoarthritis in China increased from 51.8, 4.6, and 1.8 million, respectively, in 1990, to 132.8, 10.7, and 4.7 million, respectively, in 2019, and the average annual percentage changes were 3.286, 2.938, and 3.324, respectively. The prevalence and YLDs peaked in the population aged over 90 years old, while the incidence peaked in the population aged around 50 years old. A significant positive correlation was found between osteoarthritis burden and SDI. Osteoarthritis burden is expected to continue to increase. In the population studied here, it was higher in women than in men, but this may invert by 2039. CONCLUSIONS The prevalence, incidence, and YLDs of osteoarthritis had significantly increased and may continue to increase during the next 2 decades. Prevention and treatment strategies should target women, middle-aged individuals, and the elderly.


Assuntos
Carga Global da Doença , Osteoartrite , Idoso , Masculino , Pessoa de Meia-Idade , Humanos , Feminino , Idoso de 80 Anos ou mais , Teorema de Bayes , Prevalência , Osteoartrite/epidemiologia , Incidência , China/epidemiologia , Saúde Global
10.
ACS Omega ; 9(3): 3565-3573, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38284057

RESUMO

The demand for clean-energy collection has gradually increased in recent years, making triboelectric nanogenerators a promising research field, because of their advantages in convenient manufacturing, diversified materials, and diverse synthesis and modification possibilities. However, recent studies indicate that charge decay, a major limiting factor in the triboelectric output, prevents the induced charge from combining with the bottom electrode, leading to charge loss. The use of charge-trapping sites to retain the induced charge generated during the friction process is an important solution in the field of triboelectric nanogenerator research. This study proposes the use of an elastic ink with macroscopic magnetism as trapping sites by coating the ink as dots between the polytetrafluoroethylene (PTFE) dielectric layer and the electrode layer. Nickel particles in the magnetic ink are doped into the system as microcapacitors, which prevent the combination of the friction layer and induced charges on the back electrode. Because the nickel itself can be used as a charge-potential trap to capture the charge introduced by the charge-injection process, the charge can be maintained for a long time and achieve a long-term high-output state. The output voltage was more than 6 times that of the reference group without the magnetic-ink coating after 3 h. The results provide a reference direction for research on preventing charge decay and trapping charges in triboelectric nanogenerators.

11.
Appl Microbiol Biotechnol ; 108(1): 57, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38180553

RESUMO

With the inappropriate use of antibiotics, antibiotic resistance has emerged as a major dilemma for patients infected with Pseudomonas aeruginosa. Elastase B (LasB), a crucial extracellular virulence factor secreted by P. aeruginosa, has been identified as a key target for antivirulence therapy. Quercetin, a natural flavonoid, exhibits promising potential as an antivirulence agent. We aim to evaluate the impact of quercetin on P. aeruginosa LasB and elucidate the underlying mechanism. Molecular docking and molecular dynamics simulation revealed a rather favorable intermolecular interaction between quercetin and LasB. At the sub-MICs of ≤256 µg/ml, quercetin was found to effectively inhibit the production and activity of LasB elastase, as well as downregulate the transcription level of the lasB gene in both PAO1 and clinical strains of P. aeruginosa. Through correlation analysis, significant positive correlations were shown between the virulence gene lasB and the QS system regulatory genes lasI, lasR, rhlI, and rhlR in clinical strains of P. aeruginosa. Then, we found the lasB gene expression and LasB activity were significantly deficient in PAO1 ΔlasI and ΔlasIΔrhlI mutants. In addition, quercetin significantly downregulated the expression levels of regulated genes lasI, lasR, rhlI, rhlR, pqsA, and pqsR as well as effectively attenuated the synthesis of signaling molecules 3-oxo-C12-HSL and C4-HSL in the QS system of PAO1. Quercetin was also able to compete with the natural ligands OdDHL, BHL, and PQS for binding to the receptor proteins LasR, RhlR, and PqsR, respectively, resulting in the formation of more stabilized complexes. Taken together, quercetin exhibits enormous potential in combating LasB production and activity by disrupting the QS system of P. aeruginosa in vitro, thereby offering an alternative approach for the antivirulence therapy of P. aeruginosa infections. KEY POINTS: • Quercetin diminished the content and activity of LasB elastase of P. aeruginosa. • Quercetin inhibited the QS system activity of P. aeruginosa. • Quercetin acted on LasB based on the QS system.


Assuntos
Pseudomonas aeruginosa , Quercetina , Humanos , Quercetina/farmacologia , Virulência , Pseudomonas aeruginosa/genética , Simulação de Acoplamento Molecular , Elastase Pancreática
12.
Med Sci Monit ; 29: e942346, 2023 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-38142297

RESUMO

BACKGROUND Osteoporosis is a systemic chronic disease characterized by bone mineral density (BMD) reduction. This study aimed to assess the prevalence of osteoporosis and fracture risks in northwestern China and investigate the related anthropometric risk factors. MATERIAL AND METHODS Between July 2022 and August 2022, 1429 participants (1295 females, 134 males) with measured BMD were recruited to participate in this cross-sectional study. Data on height, weight, and T score were collected. Spearman's correlation and multiple linear regression analysis were used to investigate the relationships between various demographic factors and BMD and the 10-year risk of major osteoporotic fracture (MO) and hip fracture (HP). RESULTS The overall prevalence of osteoporosis in northwest China was 42.34%, with 44.56% in females and 20.90% in males. Age negatively affects females' T scores (r=-0.304, P<0.05), and height positively influences both sexes' T scores (r=0.059 P<0.05). Age (r=0.148, P<0.05) and height were positive predictors of MO (r=0.027, P<0.05), while weight was a negative predictor (r=-0.035, P<0.05). The conclusion for HP was consistent with that of MO, except for the T score, which was a positive predictor of HP (r=0.014, P<0.05). CONCLUSIONS The prevalence of osteoporosis in northeast China is high. The association between anthropometric parameters and osteoporosis in adults in northwest China is different between sexes.


Assuntos
Osteoporose , Fraturas por Osteoporose , Adulto , Masculino , Feminino , Humanos , Estudos Transversais , Prevalência , Osteoporose/epidemiologia , Densidade Óssea , China/epidemiologia , Fatores de Risco , Absorciometria de Fóton
13.
Microb Pathog ; 185: 106397, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37852553

RESUMO

The escalating prevalence of carbapenem-resistant Pseudomonas aeruginosa (CRPA) poses a significant threat to global public health through the spread of its 'high-risk' clones. Immediate and decisive research into antimicrobial agents against CRPA is crucial for the development of effective measures and interventions. Overexpression of the MexAB-OprM efflux pump is one of the major mechanisms of CRPA. Since the active efflux of antibacterial agents plays a significant role in mediating drug resistance in CRPA, the inhibition of efflux pumps has become a promising strategy to restore antibacterial potency. Piperine (PIP) has been proven to be a promising efflux pump inhibitor in some bacteria. However, there are no studies on whether PIP can act as a potential efflux pump inhibitor in CRPA. The present study aimed to identify the antibacterial activity of PIP against CRPA and to evaluate the effect on the MexAB-OprM efflux pump. Molecular docking was used to analyze the possible interaction of PIP with the proteins of the MexAB-OprM efflux pump in CRPA. The effect of PIP on the expression of the MexAB-OprM efflux pump was investigated by real-time quantitative PCR (qPCR) and ethidium bromide accumulation efflux assay. The effect of PIP on CRPA imipenem (IPM) resistance was investigated by the checkerboard dilution method. The results demonstrated that PIP exhibited the lowest binding affinity of -9.1 kcal towards efflux pump proteins. A synergistic effect between PIP and IPM on CRPA was observed. More importantly, PIP effectively hindered the efflux of ethidium bromide and IPM by up-regulating MexR gene expression while down-regulating MexA, MexB, and OprM gene expressions. In conclusion, PIP could enhance the antibacterial activity of IPM by inhibiting the MexAB-OprM efflux pump. Our work proved that PIP had the potential to be an efflux pump inhibitor of CRPA.


Assuntos
Imipenem , Pseudomonas aeruginosa , Imipenem/farmacologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Etídio/farmacologia , Simulação de Acoplamento Molecular , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Testes de Sensibilidade Microbiana
14.
Nat Commun ; 14(1): 6734, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872158

RESUMO

Materials that break multiple symmetries allow the formation of four-fermion condensates above the superconducting critical temperature (Tc). Such states can be stabilized by phase fluctuations. Recently, a fermionic quadrupling condensate that breaks the Z2 time-reversal symmetry was reported in Ba1-xKxFe2As2. A phase transition to the new state of matter should be accompanied by a specific heat anomaly at the critical temperature where Z2 time-reversal symmetry is broken ([Formula: see text]). Here, we report on detecting two anomalies in the specific heat of Ba1-xKxFe2As2 at zero magnetic field. The anomaly at the higher temperature is accompanied by the appearance of a spontaneous Nernst effect, indicating the breakdown of Z2 symmetry. The second anomaly at the lower temperature coincides with the transition to a zero-resistance state, indicating the onset of superconductivity. Our data provide the first example of the appearance of a specific heat anomaly above the superconducting phase transition associated with the broken time-reversal symmetry due to the formation of the novel fermion order.

15.
Virus Res ; 335: 199184, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532140

RESUMO

Pseudomonas aeruginosa is a clinically common conditionally pathogenic bacterium, and the abuse of antibiotics has exacerbated its drug resistance in recent years. This has resulted in extensive reports about the usage of Pseudomonas aeruginosa phage as a novel antibacterial drug. In this study, we isolated a novel phage HZ2201 with a broad lytic spectrum. The lytic rate of this phage against Pseudomonas aeruginosa reached 78.38% (29/37), including 25 multi-drug- and carbapenem-resistant Pseudomonas aeruginosa strains. Transmission electron microscopy revealed that phage HZ2201 belongs to the class Caudoviricetes. Biological characterization showed that phage HZ2201 had an latent period of 40 min, a lytic period of 20 min, and a burst size of 440 PFU/cell, with improved tolerance to temperature and pH. Considering genomic analysis, the HZ2201 genome was a circular double-stranded DNA with a size of 45,431 bp and a guanine-cytosine (G + C) content of 52.16%, and contained 3 tRNAs. 27 of the 74 open reading frames (ORFs) annotated by the Rapid Annotation using Subsystem Technology (RAST) tool could be matched to the genomes of known functions, and no genes related to virulence and antibiotic resistance were found. The phylogenetic tree suggests that phage HZ2201 is highly related to the phage ZCPS1 and PaP3, and ORF57 and ORF17 are predicted to encode a holin and an endolysin, respectively. Cell lysis by HZ2201 proceeds through the holin-endolysin system, suggesting that it is a novel phage. Additionally, we demonstrated that phage HZ2201 has a high inhibitory capacity against Pseudomonas aeruginosa biofilms. The results of our study suggest that phage HZ2201 is a novel potential antimicrobial agent for treating drug-resistant Pseudomonas aeruginosa infection.


Assuntos
Bacteriófagos , Fagos de Pseudomonas , Bacteriófagos/genética , Pseudomonas aeruginosa/genética , Filogenia , Fagos de Pseudomonas/genética , Genômica/métodos , Genoma Viral , Biofilmes
16.
Macromol Biosci ; 23(4): e2200502, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36637816

RESUMO

The regeneration strategy for bone defects is greatly limited by the bone microenvironment, and excessive reactive oxygen species (ROS) seriously hinder the formation of new bone. Reduced graphene oxide (rGO) is expected to meet the requirements because of its ability to scavenge free radicals through electron transfer. Antioxidant hydrogels based on gelatine methacrylate (GM), acrylyl-ß-cyclodextrin (Ac-CD), and rGO functionalized with ß-cyclodextrin (ß-CD) are developed for skull defect regeneration, but the mechanism of how rGO-based hydrogels enhance bone repair remains unclear. In this work, it is confirmed that the GM/Ac-CD/rGO hydrogel has good antioxidant capacity, and promotes osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and angiogenesis of human umbilical vein endothelial cells (HUVECs). The rGO-based hydrogel affects ZEB1/Notch1 to promote tube formation. Furthermore, two-photon laser scanning microscopy is used to observe the ROS in a skull defect. The rGO-based hydrogel promotes type H vessel formation in a skull defect. In conclusion, the hydrogel neutralizes ROS in the vicinity of a skull defect and stimulates ZEB1/Notch1 to promote the coupling of osteogenesis and angiogenesis, which may be a possible approach for bone regeneration.


Assuntos
Grafite , Osteogênese , Humanos , Grafite/farmacologia , Espécies Reativas de Oxigênio , Hidrogéis/farmacologia , Antioxidantes , Regeneração Óssea , Diferenciação Celular , Células Endoteliais da Veia Umbilical Humana , Gelatina/farmacologia , Homeobox 1 de Ligação a E-box em Dedo de Zinco , Receptor Notch1
17.
J Int Med Res ; 51(1): 3000605221147444, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36628439

RESUMO

OBJECTIVE: To identify key genes involved in occurrence and development of polycystic ovary syndrome (PCOS). METHODS: By downloading the GSE85932 dataset from the GEO database, we used bioinformatical analysis to analyse differentially expressed genes (DEGs) from blood samples of eight women with PCOS and eight matched controls. Following bioinformatic analysis, we performed a cross-sectional study of serum samples taken from 79 women with PCOS and 36 healthy controls. RESULTS: From the 178 DEGs identified by bioinformatical analysis, 15 genes were identified as significant, and of these, ORM1 and ORM2 were selected for further verification as potential biomarkers for PCOS. Serum ORM1 and ORM2 levels were significantly increased in women with PCOS, and had a high diagnostic value. ORM1 and ORM2 were positively correlated with testosterone, cholesterol, and triglycerides. ORM1 levels were negatively correlated with high density lipoprotein (HDL) while ORM2 levels showed no significant correlation. CONCLUSIONS: ORM may be an effective biomarker for the diagnosis of PCOS and its monitoring may be a useful therapeutic strategy.


Assuntos
Síndrome do Ovário Policístico , Feminino , Humanos , Síndrome do Ovário Policístico/diagnóstico , Síndrome do Ovário Policístico/genética , Estudos Transversais , Colesterol , Triglicerídeos , Testosterona
18.
Polymers (Basel) ; 14(23)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36501562

RESUMO

A complex signal processing technique is usually required to process the data in most sensor design structures, and integration into real applications is also challenging. This work presents a dynamic rotational sensor using polymethyl methacrylate (PMMA) fiber for robot movement assessment. The sensor design structure is based on the coupling of light intensity, in which two PMMA fibers are twisted together. Both fibers are bent after twisting and attached on the linear translation stage, which is further attached to the robot. The variation in bending radius causes the bending loss, and that loss is coupled in the second fiber. The change in the macro-bend radius corresponds to the rotation of the robot. Experimental results indicate that the sensor can operate in full rotational cycle (i.e., 0°-360°) as well as for clock and anti-clockwise rotation. Moreover, different rotational speeds (2°/s, 3°/s, 5°/s, and 10°/s) were carried out. The hysteresis loss of the sensor was about 0.77% and the sensitivity was 8.69 nW/°. The presented dynamic rotational sensor is cost-effective and easily integrated into the robot structure to analyze the robot's circular motion.

19.
Nanomicro Lett ; 15(1): 2, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36441263

RESUMO

While boron nitride (BN) is widely recognized as the most promising thermally conductive filler for rapidly developing high-power electronic devices due to its excellent thermal conductivity and dielectric properties, a great challenge is the poor vertical thermal conductivity when embedded in composites owing to the poor interfacial interaction causing severe phonon scattering. Here, we report a novel surface modification strategy called the "self-modified nanointerface" using BN nanocrystals (BNNCs) to efficiently link the interface between BN and the polymer matrix. Combining with ice-press assembly method, an only 25 wt% BN-embedded composite film can not only possess an in-plane thermal conductivity of 20.3 W m-1 K-1 but also, more importantly, achieve a through-plane thermal conductivity as high as 21.3 W m-1 K-1, which is more than twice the reported maximum due to the ideal phonon spectrum matching between BNNCs and BN fillers, the strong interaction between the self-modified fillers and polymer matrix, as well as ladder-structured BN skeleton. The excellent thermal conductivity has been verified by theoretical calculations and the heat dissipation of a CPU. This study provides an innovative design principle to tailor composite interfaces and opens up a new path to develop high-performance composites.

20.
Medicine (Baltimore) ; 101(38): e30833, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36197192

RESUMO

BACKGROUND: Actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1) is associated with prognosis in many cancers. The aim of this study was to systematically evaluate the potential correlation between AFAP1-AS1 and the prognosis of digestive system cancers (DSC). METHODS: EMBASE, Web of Science, Cochrane Library, PubMed, Wanfang Data (Chinese), and CNKI (Chinese) were comprehensively searched for literature published from the establishment of the database to September 2021.All case-control studies that met the inclusion criteria were retrieved; additionally manual retrieval and literature tracing was performed. After extracting the relevant data, Revman 5.3.5 software was used for meta-analysis. RESULTS: Eighteen studies were included in analyses, high expression of AFAP1-AS1 was significantly correlated with poor prognosis in DSC, including overall survival (HR = 1.93, 95% CI: 1.72-2.17, P < .001) and disease-free survival/progression-free survival (HR = 1.87, 95% CI: 1.56-2.26, P < .001). In addition, the expression of AFAP1-AS1 was significantly correlated with tumor size, tumor stage, and lymph node metastasis. CONCLUSION: High expression of AFAP1-AS1 was associated with poor prognosis in DSC. Therefore, it could be used as a potential marker for evaluating prognosis in DSC.


Assuntos
Neoplasias do Sistema Digestório , RNA Longo não Codificante , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Sistema Digestório/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Prognóstico , RNA Antissenso , RNA Longo não Codificante/genética
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