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1.
Pestic Biochem Physiol ; 204: 106089, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39277402

RESUMO

The tomato leafminer, Tuta absoluta (Meyrick), one of the most economically destructive pests of tomato, causes severe yields losses of tomato production globally. Rapid evolution of insecticide resistance requires the development of alternative control strategy for this pest. RNA interference (RNAi) represents a promising, innovative control strategy against key agricultural insect pests, which has recently been licensed for Colorado Potato Beetle control. Here two essential genes, voltage-gated sodium channel (Nav) and NADPH-cytochrome P450 reductase (CPR) were evaluated as targets for RNAi using an ex vivo tomato leaf delivery system. Developmental stage-dependent expression profiles showed TaNav was most abundant in adult stages, whereas TaCPR was highly expressed in larval and adult stages. T. absoluta larvae feeding on tomato leaflets treated with dsRNA targeting TaNav and TaCPR showed significant knockdown of gene expression, leading to reduction in adult emergence. Additionally, tomato leaves treated with dsRNA targeting these two genes were significantly less damaged by larval feeding and mining. Furthermore, bioassay with LC30 doses of λ-cyholthin showed that silencing TaNav and TaCPR increased T. absoluta mortality about 32.2 and 17.4%, respectively, thus indicating that RNAi targeting TaNav and TaCPR could increase the susceptibility to λ-cyholthin in T. absoluta. This study demonstrates the potential of using RNAi targeting key genes, like TaNav and TaCPR, as an alternative technology for the control of this most destructive tomato pests in the future.


Assuntos
Inseticidas , Larva , Folhas de Planta , Interferência de RNA , Solanum lycopersicum , Animais , Solanum lycopersicum/parasitologia , Solanum lycopersicum/genética , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Larva/genética , Mariposas/efeitos dos fármacos , Mariposas/genética , Mariposas/crescimento & desenvolvimento , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Canais de Sódio Disparados por Voltagem/genética , Canais de Sódio Disparados por Voltagem/metabolismo , Resistência a Inseticidas/genética , Piretrinas
2.
Artigo em Inglês | MEDLINE | ID: mdl-39316296

RESUMO

BACKGROUND: Fruquintinib has received approval for the management of patients with chemotherapy-resistant metastatic colorectal cancer (mCRC). However, combination of fruquintinib with immune checkpoint inhibitors (ICIs) is yet to be extensively studied. This study aims to assess the clinical efficacy, safety, and prognostic indicators of treatment regimen combining fruquintinib with ICIs in mCRC patients. METHODS: We analyzed data from mCRC patients who were administered fruquintinib either as a monotherapy or in conjunction with ICIs following conventional chemotherapy. Parameters such as the objective response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS), and incidence of adverse events were meticulously evaluated. Furthermore, the relationship between blood markers and patient prognosis was examined. RESULTS: A total of 72 mCRC patients were included in this study, with a median observation period of 48 months, 19 were treated with fruquintinib alone, while 53 received a combination therapy involving fruquintinib and ICIs. The combined therapy group exhibited superior ORR and DCR compared to the fruquintinib monotherapy group. Additionally, significant improvements in OS and PFS were observed in the combined treatment group. The occurrence of adverse events was generally manageable and well-tolerated across both groups, with no significant difference in incidence rates. Notably, albumin levels were identified as a prognostic marker for PFS and OS in the univariate Cox regression analysis. CONCLUSIONS: The combination of fruquintinib with ICIs demonstrated enhanced clinical efficacy and improved survival outcomes compared to fruquintinib monotherapy in mCRC patients. The safety of the combination regimen was deemed manageable and acceptable.

3.
J Hazard Mater ; 478: 135494, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39141940

RESUMO

The widespread use of organophosphate flame retardants (OPFRs), a serious type of pervasive environmental contaminants, has led to a global concern regarding their diverse toxicities to living beings. Using a combination of experimental and theoretical approaches, we systematically studied the adsorption, accumulation, and influence of a series of OPFRs on the lipid membranes of bacteria and cells. Our results revealed that OPFRs can aggregate in lipid membranes, leading to the destruction of membrane integrity. During this process, the molecular structure of the OPFRs is a dominant factor that significantly influences the strength of their interaction with the lipid membrane, resulting in varying degrees of biotoxicity. Triphenyl phosphate (TPHP), owing to its large molecular size and strong hydrophobicity, causes severe membrane disruption through the formation of nanoclusters. The corresponding severe toxicity originates from the phase transitions of the lipid membranes. In contrast, smaller OPFRs such as triethyl phosphate (TEP) and tris(2-chloroethyl) phosphate (TCEP) have weaker hydrophobicity and induce minimal membrane disturbance and ineffective damage. In vivo, gavage of TPHP induced more severe barrier damage and inflammatory infiltration in mice than TEP or TCEP, confirming the higher toxicity of TPHP. Overall, our study elucidates the structure-dependent adsorption of OPFRs onto lipid membranes, highlighting their destructive interactions with membranes as the origin of OPFR toxicity.


Assuntos
Retardadores de Chama , Organofosfatos , Retardadores de Chama/toxicidade , Adsorção , Animais , Organofosfatos/toxicidade , Organofosfatos/química , Lipídeos de Membrana/química , Camundongos , Interações Hidrofóbicas e Hidrofílicas , Escherichia coli/efeitos dos fármacos
4.
J Dig Dis ; 25(7): 453-462, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39211938

RESUMO

OBJECTIVE: We aimed to investigate the role of forkhead box O1 (FoxO1) inhibitor AS1842856 (AS) in nonalcoholic steatohepatitis (NASH) mice and the potential mechanisms. METHODS: Mice were given methionine-choline-sufficient (MCS), or methionine- and choline-deficient (MCD) diet for 5 weeks, along with AS (60 mg/kg) or vehicle gavage treatment (0.2 mL/day). Body and liver weight, serum triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), alanine aminotransferase (ALT), aspartate aminotransferase (AST), fasting glucose and insulin levels were measured. Liver macrophage infiltration and ileal ZO-1 protein expression were also detected. Interleukin (IL)-6, IL-1ß, and tumor necrosis factor (TNF)-α, sterol regulatory element binding protein (SREBP)-1c, phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6-phosphatase (G6Pase), α-smooth muscle actin (SMA), recombinant collagen type III α1 (Col3a1), and connective tissue growth factor (Ctgf) expressions were measured. Stool samples were collected for 16S rDNA sequencing. RESULTS: Compared to the MCD group, AS attenuated liver weight, reduced serum TG, ALT, and AST levels, increased HDL-C levels, mitigated hepatic steatosis, decreased macrophage infiltration, and augmented ileal ZO-1 proteins in NASH mice. It also reduced the levels of IL-6, IL-1ß, and TNF-α, alongside with the Srebp-1c mRNA expression. However, no significant effects on Pepck, G6Pase, α-SMA, Col3a1, or Ctgf were observed. Furthermore, AS promoted diversity and altered gut microbiota composition in NASH mice, causing increased beneficial bacteria like Akkermansia muciniphila, Parabacteroides distasonis, and Prevotellamassilia, which were associated with metabolic functions. CONCLUSION: FoxO1 inhibitor AS ameliorated hepatic steatosis, inflammation, and intestinal dysbiosis in NASH mice, making it a potentially promising treatment for NASH.


Assuntos
Proteína Forkhead Box O1 , Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Camundongos , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Masculino , Fígado/patologia , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Hepatite/tratamento farmacológico , Hepatite/prevenção & controle
5.
J Chem Inf Model ; 64(15): 6205-6215, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39074901

RESUMO

Accurate protein-ligand binding poses are the prerequisites of structure-based binding affinity prediction and provide the structural basis for in-depth lead optimization in small molecule drug design. However, it is challenging to provide reasonable predictions of binding poses for different molecules due to the complexity and diversity of the chemical space of small molecules. Similarity-based molecular alignment techniques can effectively narrow the search range, as structurally similar molecules are likely to have similar binding modes, with higher similarity usually correlated to higher success rates. However, molecular similarity is not consistently high because molecules often require changes to achieve specific purposes, leading to reduced alignment precision. To address this issue, we propose a new alignment method─Z-align. This method uses topological structural information as a criterion for evaluating similarity, reducing the reliance on molecular fingerprint similarity. Our method has achieved success rates significantly higher than those of other methods at moderate levels of similarity. Additionally, our approach can comprehensively and flexibly optimize bond lengths and angles of molecules, maintaining a high accuracy even when dealing with larger molecules. Consequently, our proposed solution helps in achieving more accurate binding poses in protein-ligand docking problems, facilitating the development of small molecule drugs. Z-align is freely available as a web server at https://cloud.zelixir.com/zalign/home.


Assuntos
Simulação de Acoplamento Molecular , Proteínas , Ligantes , Proteínas/química , Proteínas/metabolismo , Ligação Proteica , Desenho de Fármacos , Conformação Proteica , Sítios de Ligação
6.
Bioresour Technol ; 406: 131007, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38901747

RESUMO

This study investigated the effects of carbon/nitrogen (C/N) ratio on microbial community in moving bed biofilm reactor (MBBR) using metagenomic analysis, and the dynamic changes of relevant antibiotic resistance genes (ARGs) were also analyzed. The results showed that under low C/N ratio, MBBR exhibited average removal rates of 98.41 % for ammonia nitrogen and 75.79 % for total nitrogen. Metagenomic analysis showed low C/N ratio altered the structure of biofilm and water microbiota, resulting in the detachment of bacteria such as Actinobacteria from biofilm into water. Furthermore, sulfamethazine (SMZ)-resistant bacteria and related ARGs were released into water under low C/N ratio, which lead to the increase of SMZ resistance rate to 90%. Moreover, most dominant genera are potential hosts for both nitrogen cycle related genes and ARGs. Specifically, Nitrosomonas that carried gene sul2 might be released from biofilm into water. These findings implied the risks of antibiotic resistance dissemination in MBBR under low C/N ratio.


Assuntos
Biofilmes , Reatores Biológicos , Carbono , Metagenômica , Nitrogênio , Biofilmes/efeitos dos fármacos , Carbono/farmacologia , Reatores Biológicos/microbiologia , Metagenômica/métodos , Resistência Microbiana a Medicamentos/genética , Microbiota/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Bactérias/genética
7.
Adv Healthc Mater ; 13(22): e2400659, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38700840

RESUMO

The exploration of sonodynamic therapy (SDT) as a possible replacement for antibiotics by creating reactive oxygen species (ROS) is suggested as a non-drug-resistant theranostic method. However, the low-efficiency ROS generation and complex tumor microenvironment which can deplete ROS and promote tumor growth will cause the compromised antibacterial efficacy of SDT. Herein, through an oxygen vacancy engineering strategy, TiO2- x microspheres with an abundance of Ti3+ are synthesized using a straightforward reductant co-assembly approach. The narrow bandgaps and Ti3+/Ti4+-mediated multiple-enzyme catalytic activities of the obtained TiO2- x microspheres make them suitable for use as sonosensitizers and nanozymes. When graphene quantum dot (GQD) nanoantibiotics are deposited on TiO2- x microspheres, the resulting GQD/TiO2- x shows an increased production of ROS, which can be ascribed to the accelerated separation of electron-hole pairs, as well as the peroxidase-like catalytic activity mediated by Ti3+, and the depletion of glutathione mediated by Ti4+. Moreover, the catalytic activities of TiO2- x microspheres are amplified by the heterojunctions-accelerated carrier transfer. In addition, GQDs can inhibit Topo I, displaying strong antibacterial activity and further enhancing the antibacterial activity. Collectively, the combination of GQD/TiO2- x-mediated SDT/NCT with nanoantibiotics can result in a synergistic effect, allowing for multimodal antibacterial treatment that effectively promotes wound healing.


Assuntos
Antibacterianos , Grafite , Pontos Quânticos , Espécies Reativas de Oxigênio , Titânio , Pontos Quânticos/química , Titânio/química , Titânio/farmacologia , Grafite/química , Grafite/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Camundongos , Antibacterianos/química , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Catálise , Humanos , Terapia por Ultrassom/métodos , Infecções Bacterianas/tratamento farmacológico , Microesferas
8.
ACS Appl Mater Interfaces ; 16(17): 21689-21698, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38629436

RESUMO

Plasmonic nanozymes bring enticing prospects for catalytic sterilization by leveraging plasmon-engendered hot electrons. However, the interface between plasmons and nanozymes as the mandatory path of hot electrons receives little attention, and the mechanisms of plasmonic nanozymes still remain to be elucidated. Herein, a plasmonic carbon-dot nanozyme (FeCG) is developed by electrostatically assembling catalytic iron-doped carbon dots (Fe-CDs) with plasmonic gold nanorods. The energy harvesting and hot-electron migration are remarkably expedited by a spontaneous organic-inorganic heterointerface holding a Fermi level-induced interfacial electric field. The accumulated hot electrons are then fully utilized by conductive Fe-CDs to boost enzymatic catalysis toward overproduced reactive oxygen species. By synergizing with localized heating from hot-electron decay, FeCG achieves rapid and potent disinfection with an antibacterial efficiency of 99.6% on Escherichia coli within 5 min and is also effective (94.2%) against Staphylococcus aureus. Our work presents crucial insights into the organic-inorganic heterointerface in advanced plasmonic biocidal nanozymes.


Assuntos
Antibacterianos , Carbono , Escherichia coli , Ouro , Staphylococcus aureus , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Carbono/química , Catálise , Ouro/química , Antibacterianos/química , Antibacterianos/farmacologia , Pontos Quânticos/química , Transporte de Elétrons , Ferro/química
9.
Aquat Toxicol ; 271: 106918, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38598945

RESUMO

Antibiotics are commonly found in the aquatic environment, which can affect microbial community compositions and activities, and even have potential adverse impacts on human and ecosystem health. The current understanding of the effects of antibiotics on microalgae growth and algal dissolved organic matter (DOM) remains indistinct. To understand the toxic effects of antibiotics on the microalgae, Microcystis aeruginosa was exposed to clarithromycin (CLA) in this study. Cell density determination, chlorophyll content determination, and organic spectrum analysis were conducted to show the effect of CLA exposure on the growth, photosynthetic activity, and organic metabolic processes of Microcystis aeruginosa. The findings revealed that the physiological status of algae could be significantly influenced by CLA exposure in aquatic environments. Specifically, exposure to 1 µg/L CLA stimulated the growth and photosynthetic activity of algal cells. Conversely, CLA above 10 µg/L led to the inhibition of algal cell growth and photosynthesis. Notably, the inhibitory effects intensified with the increasing concentration of CLA. The molecular weight of DOM produced by Microcystis aeruginosa increased when exposed to CLA. Under the exposure of 60 µg/L CLA, a large number of algal cells ruptured and died, and the intracellular organic matter was released into the algal liquid. This resulted in an increase in high molecular weight substances and soluble microbial-like products in the DOM. Exposure to 1 and 10 µg/L CLA stimulated Microcystis aeruginosa to produce more humic acid-like substances, which may be a defense mechanism against CLA. The results were useful for assessing the effects of antibiotic pollution on the stability of the microalgae population and endogenous DOM characteristics in aquatic ecosystems.


Assuntos
Claritromicina , Microcystis , Fotossíntese , Poluentes Químicos da Água , Microcystis/efeitos dos fármacos , Microcystis/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Fotossíntese/efeitos dos fármacos , Claritromicina/toxicidade , Claritromicina/farmacologia , Microalgas/efeitos dos fármacos , Clorofila/metabolismo , Antibacterianos/toxicidade
10.
Signal Transduct Target Ther ; 9(1): 79, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38565886

RESUMO

Fluoropyrimidine-based combination chemotherapy plus targeted therapy is the standard initial treatment for unresectable metastatic colorectal cancer (mCRC), but the prognosis remains poor. This phase 3 trial (ClinicalTrials.gov: NCT03950154) assessed the efficacy and adverse events (AEs) of the combination of PD-1 blockade-activated DC-CIK (PD1-T) cells with XELOX plus bevacizumab as a first-line therapy in patients with mCRC. A total of 202 participants were enrolled and randomly assigned in a 1:1 ratio to receive either first-line XELOX plus bevacizumab (the control group, n = 102) or the same regimen plus autologous PD1-T cell immunotherapy (the immunotherapy group, n = 100) every 21 days for up to 6 cycles, followed by maintenance treatment with capecitabine and bevacizumab. The main endpoint of the trial was progression-free survival (PFS). The median follow-up was 19.5 months. Median PFS was 14.8 months (95% CI, 11.6-18.0) for the immunotherapy group compared with 9.9 months (8.0-11.8) for the control group (hazard ratio [HR], 0.60 [95% CI, 0.40-0.88]; p = 0.009). Median overall survival (OS) was not reached for the immunotherapy group and 25.6 months (95% CI, 18.3-32.8) for the control group (HR, 0.57 [95% CI, 0.33-0.98]; p = 0.043). Grade 3 or higher AEs occurred in 20.0% of patients in the immunotherapy group and 23.5% in the control groups, with no toxicity-associated deaths reported. The addition of PD1-T cells to first-line XELOX plus bevacizumab demonstrates significant clinical improvement of PFS and OS with well tolerability in patients with previously untreated mCRC.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Oxaloacetatos , Humanos , Bevacizumab/uso terapêutico , Capecitabina/uso terapêutico , Oxaliplatina , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Imunoterapia
11.
Int J Biol Macromol ; 265(Pt 1): 130644, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462102

RESUMO

The main proteinase (Mpro) of SARS-CoV-2 plays a critical role in cleaving viral polyproteins into functional proteins required for viral replication and assembly, making it a prime drug target for COVID-19. It is well known that noncompetitive inhibition offers potential therapeutic options for treating COVID-19, which can effectively reduce the likelihood of cross-reactivity with other proteins and increase the selectivity of the drug. Therefore, the discovery of allosteric sites of Mpro has both scientific and practical significance. In this study, we explored the binding characteristics and inhibiting process of Mpro activity by two recently reported allosteric inhibitors, pelitinib and AT7519 which were obtained by the X-ray screening experiments, to probe the allosteric mechanism via molecular dynamic (MD) simulations. We found that pelitinib and AT7519 can stably bind to Mpro far from the active site. The binding affinity is estimated to be -24.37 ± 4.14 and - 26.96 ± 4.05 kcal/mol for pelitinib and AT7519, respectively, which is considerably stable compared with orthosteric drugs. Furthermore, the strong binding caused clear changes in the catalytic site of Mpro, thus decreasing the substrate accessibility. The community network analysis also validated that pelitinib and AT7519 strengthened intra- and inter-domain communication of Mpro dimer, resulting in a rigid Mpro, which could negatively impact substrate binding. In summary, our findings provide the detailed working mechanism for the two experimentally observed allosteric sites of Mpro. These allosteric sites greatly enhance the 'druggability' of Mpro and represent attractive targets for the development of new Mpro inhibitors.


Assuntos
Aminoquinolinas , Compostos de Anilina , COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Peptídeo Hidrolases/metabolismo , Inibidores de Proteases/química , Simulação de Acoplamento Molecular , Cisteína Endopeptidases/metabolismo , Simulação de Dinâmica Molecular , Antivirais/farmacologia , Antivirais/química
12.
Cancer Res ; 84(10): 1613-1629, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38381538

RESUMO

Neutrophil extracellular traps (NET), formed by the extracellular release of decondensed chromatin and granules, have been shown to promote tumor progression and metastasis. Tumor-associated neutrophils in hepatocellular carcinoma (HCC) are prone to NET formation, highlighting the need for a more comprehensive understanding of the mechanisms of action of NETs in liver cancer. Here, we showed that DNA of NETs (NET-DNA) binds transmembrane and coiled-coil domains 6 (TMCO6) on CD8+ T cells to impair antitumor immunity and thereby promote HCC progression. TGFß1 induced NET formation, which recruited CD8+ T cells. Binding to NET-DNA inhibited CD8+ T cells function while increasing apoptosis and TGFß1 secretion, forming a positive feedback loop to further stimulate NET formation and immunosuppression. Mechanistically, the N-terminus of TMCO6 interacted with NET-DNA and suppressed T-cell receptor signaling and NFκB p65 nuclear translocation. Blocking NET formation by inhibiting PAD4 induced potent antitumor effects in wild-type mice but not TMCO6-/- mice. In clinical samples, CD8+ T cells expressing TMCO6 had an exhausted phenotype. TGFß1 signaling inhibition or TMCO6 deficiency combined with anti-PD-1 abolished NET-driven HCC progression in vivo. Collectively, this study unveils the role of NET-DNA in impairing CD8+ T-cell immunity by binding TMCO6 and identifies targeting this axis as an immunotherapeutic strategy for blocking HCC progression. SIGNIFICANCE: TMCO6 is a receptor for DNA of NETs that mediates CD8+ T-cell dysfunction in HCC, indicating that the NET-TMCO6 axis is a promising target for overcoming immunosuppression in liver cancer.


Assuntos
Linfócitos T CD8-Positivos , Carcinoma Hepatocelular , Armadilhas Extracelulares , Neoplasias Hepáticas , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Animais , Humanos , Camundongos , Armadilhas Extracelulares/imunologia , Armadilhas Extracelulares/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Neutrófilos/imunologia , Neutrófilos/metabolismo , DNA/imunologia , DNA/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linhagem Celular Tumoral , Masculino
13.
ACS Nano ; 18(4): 3814-3825, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38230632

RESUMO

Nanomaterials with enzyme-mimicking functions, termed nanozymes, offer attractive opportunities for biocatalysis and biomedicine. However, manipulating nanozyme selectivity poses an insurmountable hurdle. Here, we propose the concept of an energy-governed electron lock that controls electron transfer between nanozyme and substrates to achieve selectivity manipulation of enzyme-like catalysis. An electron lock can be constructed and opened, via modulating the nanozyme's electron energy to match the energy barrier of enzymatic reactions. An iron-doped carbon dot (FeCD) nanozyme with easy-to-regulate electron energy is selected as a proof of concept. Through regulating the conduction band which dominates electron energy, activatable oxidase and selective peroxidase (POD) with substrate affinity 123-fold higher than that of natural horseradish peroxidase (HRP) is achieved. Furthermore, while maintaining selectivity, FeCDs exhibit catalytic kinetics comparable to that of HRP upon transforming photons into electrons. Superior selectivity, efficient catalysis, and undetectable biotoxicity energize FeCDs as potent targeted drugs on antibiotic-resistant bacterial abscesses. An electron lock provides a robust strategy to manipulate selectivity toward advanced nanozymes.


Assuntos
Elétrons , Peroxidases , Peroxidase , Peroxidase do Rábano Silvestre , Catálise
14.
J Environ Manage ; 350: 119597, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38029495

RESUMO

Due to the limitations of traditional ultraviolet (UV) in microbial inactivation in water, it is necessary to explore a more suitable and efficient UV disinfection method. In this study, an electron beam excitation multi-wavelength ultraviolet (EBE-MW-UV) system was established and aims to analyze its differential microbial inactivation capabilities in comparison to single-wavelength UV-LEDs in waterborne applications. Furthermore, the inactivation mechanisms of this system on microorganisms were explored. The results showed that EBE-MW-UV had significantly higher inactivation effects on the Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Candida albicans in water compared to UV-LEDs (p<0.05), and the inactivation effect of EBE-MW-UV on Escherichia coli and Pseudomonas aeruginosa at the same UV dose was 3.8 and 1.9 log higher than that of UV-LEDs, respectively, EBE-MW-UV exhibited better inactivation effects on Gram-negative bacteria. Further research found that, under the majority of irradiation doses, neither EBE-MW-UV nor UV-LEDs were significantly affected by the concentration of suspended solids (5 and 20 mg/L) or humic acids (2 and 5 mg/L) in the water. Mechanism analysis revealed that during the disinfection process of EBE-MW-UV, microbial DNA and proteins were initially damaged, which prevented the occurrence of dark repair and led to bacterial inactivation. In addition, UV irradiation led to the production of additional reactive oxygen species (ROS) inside the cells, increasing cell membrane permeability and exacerbating membrane damage. This was accompanied by a decrease in energy metabolism and depletion of ATP, ultimately resulting in microbial inactivation. Therefore, EBE-MW-UV demonstrated more effective disinfection than single-wavelength UV-LEDs, showing great potential. Our research gives new insights into the characteristics of multiple wavelength ultraviolet, and provides scientific basis for the selection of new light sources in the field of ultraviolet disinfection.


Assuntos
Purificação da Água , Água , Elétrons , Purificação da Água/métodos , Microbiologia da Água , Raios Ultravioleta , Escherichia coli , Desinfecção/métodos
15.
Phys Chem Chem Phys ; 25(29): 19788-19794, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37449776

RESUMO

Fluidic transport down to the nanometer scale is of great importance for a wide range of applications such as energy harvesting, seawater desalination, and water treatment and may help to understand many biological processes. In this work, we studied the interfacial friction of liquid water on a series of nanostructures through molecular dynamics (MD) simulations. Our results reveal that the friction coefficient of the water-solid interface cannot be described using a previously reported simple function of the free energy corrugation. Considering that the water-solid friction is firmly correlated with the microscopic water motion, we proposed a probability parameter P(d, t) to classify water motion modes on a surface. We demonstrate that this parameter can be used to accurately predict the water-solid friction by simply monitoring the water binding time on a nanosurface. More importantly, according to the relationship between P(d, t) and friction, we found that the friction coefficient can be used as an indicative criterion for quantitatively assessing hydrophobic or hydrophilic materials, where the borderline is roughly 2 × 105 N s m-3. That is if the water-solid friction is less than 2 × 105 N s m-3, the surface is considered hydrophobic. But if the friction is larger than this value, the surface is hydrophilic. The present findings could help to better understand fluidic transport at the nanoscale and guide the future design of functional materials, such as super-hydrophobic and super-hydrophilic surfaces by structure engineering.

16.
Biosens Bioelectron ; 237: 115497, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37390642

RESUMO

Surface-enhanced Raman spectroscopy (SERS) sandwich biosensors have received tremendous attention in early diagnosis of bacterial infections. However, efficiently engineering nanoscale plasmonic hots pots (HS) towards ultrasensitive SERS detection still remains challenging. Herein, we propose a bioinspired synergistic HS engineering strategy to construct ultrasensitive SERS sandwich bacterial sensor (named USSB), by coupling bioinspired signal module and plasmonic enrichment module to synergistically boost the number and intensity of HS. The bioinspired signal module is based on dendritic mesoporous silica nanocarrier (DMSN) loaded with plasmonic nanoparticles and SERS tag, while magnetic Fe3O4 nanoparticles coated with Au shell are employed in plasmonic enrichment module. We demonstrate that DMSN effectively shrank nanogaps between plasmonic nanoparticles to improve HS intensity. Meanwhile, plasmonic enrichment module contributed to plenty of additional HS inside and outside individual "sandwich". Ascribing to the boosted number and intensity of HS, the constructed USSB sensor exhibits ultrahigh detection sensitivity (7 CFU/mL) and selectivity towards model pathogenic bacteria of Staphylococcus aureus. Remarkably, the USSB sensor enables fast and accurate bacterial detection in real blood samples of septic mice, achieving early diagnosis of bacterial sepsis. The proposed bioinspired synergistic HS engineering strategy opens up a new direction for constructing ultrasensitive SERS sandwich biosensors, and may promote their advancing applications in the early diagnosis and prognosis of devastating diseases.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Animais , Camundongos , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Análise Espectral Raman/métodos , Staphylococcus aureus , Bactérias , Dióxido de Silício , Ouro/química
17.
Chemosphere ; 335: 139151, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37290506

RESUMO

Microplastics (MPs) could serve as substrates for microbial colonization and biofilm formation. However, research on the effects of different types of microplastics and natural substrates on biofilm formation and community structure in the presence of antibiotic-resistant bacteria (ARB) is limited. In this study, we employed by means of microcosm experiments to analyze the situation of biofilms conditions, bacterial resistance patterns, antibiotic resistance genes (ARGs) distribution, and bacterial community on different substrates using microbial cultivation, high throughtput sequencing and PCR. The result showed that biofilms on different substrates markedly increased with time, with MPs surfaces formed more biofilm than stone. Analyses of antibiotic resistant showed negligible differences in the resistance rate to the same antibiotic at 30 d, but tetB would be selectively enriched on PP and PET. The microbial communities associated with biofilms on MPs and stones exhibited variations during different stages of formation. Notably, phylum WPS-2 and Epsilonbacteraeota were identified as the dominant microbiomes of biofilms on MPs and stones at 30 d, respectively. Correlation analysis suggested that WPS-2 could potentially be a tetracycline-resistant bacterium, while Epsilonbacteraeota did not correlate with any detected ARB. Our results emphasized the potential threat posed by MPs as attachment carriers for bacteria, particularly ARB, in aquatic environments.


Assuntos
Microplásticos , Plásticos , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Antibacterianos/farmacologia , Biofilmes
19.
ACS Nano ; 17(8): 7443-7455, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37057958

RESUMO

Alcoholic liver injury (ALI) is the leading cause of serious liver disease, whereas current treatments are mostly supportive and unable to metabolize alcohol directly. Here we report a metabolic reprogramming strategy for targeted alcohol detoxification and ALI management based on a confined cascade nanoreactor. The nanoreactor (named AA@mMOF) is designed by assembling natural enzymes of alcohol oxidase (AOx) and aldehyde dehydrogenase (ALDH) in the cavity of a mesoporous metal organic framework (mMOF) nanozyme with intrinsic catalase (CAT)-like activity. By conducting confined AOx/CAT/ALDH cascade reactions, AA@mMOF enables self-accelerated alcohol degradation (>0.5 mg·mL-1·h-1) with negligible aldehyde diffusion and accumulation, reprogramming alcohol metabolism and allowing high-efficiency detoxification. Administered to high-dose alcohol-intoxicated mice, AA@mMOF shows surprising liver targeting and accumulation performance and dramatically reduces blood alcohol concentration and rapidly reverses unconsciousness and acute liver injury to afford targeted alcoholism treatment. Moreover, AA@mMOF dramatically alleviates fat accumulation and oxidative stress in the liver of chronic alcoholism mice to block and reverse the progression of ALI. By conducting confined AOx/CAT/ALDH cascade reactions for high-efficiency alcohol metabolism reprogramming, AA@mMOF nanoreactor offers a powerful modality for targeted alcohol detoxification and ALI management. The proposed confined cascade metabolic reprogramming strategy provides a paradigm shift for the treatment of metabolic diseases.


Assuntos
Alcoolismo , Camundongos , Animais , Alcoolismo/metabolismo , Concentração Alcoólica no Sangue , Fígado/metabolismo , Etanol , Aldeído Desidrogenase/metabolismo , Nanotecnologia
20.
Patient Prefer Adherence ; 17: 583-589, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36919185

RESUMO

Background: Phosphodiesterase 5 inhibitors (PDE5Is) and other more invasive options merely provide symptomatic relief rather than a permanent improvement in erectile dysfunction (ED), whereas the long-term improvement in ED via low-intensity extracorporeal shockwave therapy (Li-ESWT) has been confirmed. So far, no comparative study of sildenafil versus Li-ESWT has been conducted with respect to treatment satisfaction. Objective: In this study, we aim to compare erectile function status and satisfaction rates in patients who received sildenafil or Li-ESWT for ED. Methods: Patients complaining of ED were considered candidates. Participants chose to enter one of two active treatment groups according to their treatment intention-either a 9-week Li-ESWT regimen or 100 mg on-demand sildenafil. The erectile function was evaluated using the erectile function domain of the International Index of Erectile Function questionnaires (IIEF-EF), while the treatment satisfaction was evaluated using the Erectile Dysfunction Inventory of Treatment Satisfaction questionnaires (EDITS). Results: We enrolled 72 participants in the study (42 in the Li-ESWT group and 30 in the sildenafil group). Patients in both groups were young men. Four weeks after the last session, the IIEF-EF score for Li-ESWT and sildenafil was 16.3± 5.5 and 18.3± 6.5 (P > 0.05), respectively. The total EDITS index of the patient version and the partner version were similar in the two groups. Among EDITS questions measuring overall satisfaction and efficacy duration, the score was higher in the Li-ESWT group. Conclusion: We found that Li-ESWT may have better satisfaction than on-demand sildenafil for young ED patients. However, further studies are needed to determine the factors influencing satisfaction.

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