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1.
FASEB J ; 37(11): e23226, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37815505

RESUMO

T-cell-mediated immunity is crucial in the immunopathology of periodontitis. The restoration of the homeostasis between the T helper cell 17 (Th17) and regulatory T cell (Treg) subsets by extracellular vesicles (EVs) obtained from human bone marrow stem cells (hBMSCs) promotes new bone formation and suppresses inflammation. Uncovering the functions of hBMSC-derived EVs in the immune microenvironment of periodontal tissue and their underlying regulatory mechanisms may shed new light on developing potential cell-free immunotherapies for periodontal regeneration. Here, we reported that the Th17/Treg ratio elevated in peripheral blood from periodontitis patients. Furthermore, we found that hBMSC-derived EVs could reduce the Th17/Treg ratio in CD4+ T cells from periodontitis patients in vitro and ameliorate conditions of experimental periodontitis in mice. Additionally, by investigating the differentially expressed miRNAs and target genes in EVs from hBMSCs stimulated with Porphyromonas gingivalis LPS using miRNA sequencing, we found that EV-miR-1246 is highly effective at downregulating the ratio of Th17/Treg in vitro. Mechanistically, EV-miR-1246 suppressed expression of its potential target angiotensin-converting enzyme 2 (ACE2) and increased the p-Yes-associated protein (YAP)1/YAP1 ratio in CD4+ T cells. Our results indicated that hBMSC-derived EVs improve periodontitis via miR-1246, consequently downregulating Th17/Treg ratio, and represented a promising therapeutic target for precision treatment in periodontitis.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , MicroRNAs , Periodontite , Humanos , Animais , Camundongos , Linfócitos T Reguladores , MicroRNAs/genética , Periodontite/terapia , Células Th17 , Proteínas Adaptadoras de Transdução de Sinal/genética , Homeostase
2.
J Clin Periodontol ; 51(9): 1210-1221, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38839576

RESUMO

AIM: To explore the levels of neutrophil extracellular traps (NETs) in patients with periodontitis and examine their effects on keratinization, barrier function of human gingival keratinocytes (HGKs) and the associated mechanisms. MATERIALS AND METHODS: Saliva, gingival crevicular fluid (GCF), clinical periodontal parameters and gingival specimens were collected from 10 healthy control subjects and 10 patients with stage II-IV periodontitis to measure the NET levels. Subsequently, mRNA and protein levels of keratinization and barrier indicators, as well as intracellular calcium and epithelial barrier permeability, were analysed in HGKs after NET stimulation. RESULTS: The study showed that NET levels significantly elevated in patients with periodontitis, across multiple specimens including saliva, GCF and gingival tissues. Stimulation of HGKs with NETs resulted in a decrease in the expressions of involucrin, cytokeratin 10, zonula occludens 1 and E-cadherin, along with decreased intracellular calcium levels and increased epithelial barrier permeability. Furthermore, the inhibition of keratinization by NETs is ERK-KLF4-dependent. CONCLUSIONS: This study indicates that NETs impair the barrier function of HGKs and suppress keratinization through ERK/KLF4 axis. These findings provide potential targets for therapeutic approaches in periodontitis to address impaired gingival keratinization.


Assuntos
Armadilhas Extracelulares , Gengiva , Líquido do Sulco Gengival , Queratinócitos , Periodontite , Humanos , Armadilhas Extracelulares/metabolismo , Gengiva/metabolismo , Líquido do Sulco Gengival/química , Queratinócitos/metabolismo , Periodontite/metabolismo , Periodontite/imunologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Fator 4 Semelhante a Kruppel , Saliva/metabolismo , Saliva/química , Cálcio/metabolismo , Cálcio/análise , Estudos de Casos e Controles , Epitélio , Queratinas/metabolismo , Caderinas/metabolismo , Caderinas/análise
3.
J Nanobiotechnology ; 22(1): 96, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448951

RESUMO

BACKGROUND: Nanoplastics (NPs) are now a new class of pollutants widely present in the soil, atmosphere, freshwater and marine environments. Nanoplastics can rapidly penetrate cell membranes and accumulate in human tissues and organs, thus posing a potential threat to human health. The heart is the main power source of the body. But up to now, the toxicological effects of long-term exposure to nanoplastics on the heart has not been revealed yet. RESULTS: We evaluated the effects of long term exposure of nanoplastics on cardiac cell/tissue in vitro and in vivo model. Furthermore, we explored the molecular mechanism by which nanoplastics exposure causes myocardial cell senescence. Immunohistochemistry, indirect immunofluorescence and ELISA were performed to detect the effects of nanoplastics on heart aging. We found that nanoplastics were able to induce significant cardiac aging through a series of biochemical assays in vivo. In vitro, the effects of nanoplastics on cardiac cell were investigated, and found that nanoplastics were able to internalize into cardiomyocytes in time and dose-dependant manner. Further biochemical analysis showed that nanoplastics induces cardiomyocytes senescence by detecting a series of senescence marker molecules. Molecular mechanism research shows that nanoplastics may cause mitochondrial destabilization by inducing oxidative stress, which leads to the leakage of mtDNA from mitochondria into the cytoplasm, and then cytoplasm-localized mt-DNA activates the cGAS-STING signaling pathway and promotes inflammation response, ultimately inducing cardiomyocytes senescence. CONCLUSIONS: In this work, we found that nanoplastics exposure induces premature aging of heart. Current research also reveals the molecular mechanism by which nanoplastics induces cardiomyocyte senescence. This study laid the foundation for further studying the potential harm of nanoplastics exposure on heart.


Assuntos
DNA Mitocondrial , Miócitos Cardíacos , Humanos , Microplásticos , Senescência Celular , Mitocôndrias , Transdução de Sinais
4.
Pestic Biochem Physiol ; 200: 105814, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582586

RESUMO

To explore active natural products against tobacco powdery mildew caused by Golovinomyces cichoracearum, an extract from the fermentation of endophytic Aspergillus fumigatus 0338 was investigated. The mechanisms of action for active compounds were also studied in detail. As a result, 14 indole alkaloid derivatives were isolated, with seven being newly discovered (1-7) and the remaining seven previously described (8-14). Notably, compounds 1-3 are rare linearly fused 6/6/5 tricyclic prenylated indole alkaloids, with asperversiamide J being the only known natural product of this kind. The isopentenyl substitutions at the 5-position in compounds 4 and 5 are also rare, with only compounds 1-(5-prenyl-1H-indol-3-yl)-propan-2-one (8) and 1-(6-methoxy-5-prenyl-1H-indol3-yl)-propan-2-one currently available. In addition, compounds 6 and 7 are new framework indole alkaloid derivatives bearing a 6-methyl-1,7-dihydro-2H-azepin-2-one ring. The purified compounds were evaluated for their activity against G. cichoracearum, and the results revealed that compounds 7 and 9 demonstrated obvious anti-G. cichoracearum activities with an inhibition rate of 82.6% and 85.2%, respectively, at a concentration of 250 µg/mL, these rates were better than that of the positive control agent, carbendazim (78.6%). The protective and curative effects of compounds 7 and 9 were also better than that of positive control, at the same concentration. Moreover, the mechanistic study showed that treatment with compound 9 significantly increased the structural tightness of tobacco leaves and directly affect the conidiospores of G. cichoracearum, thereby enhancing resistance. Compounds 7 and 9 could also induce systemic acquired resistance (SAR), directly regulating the expression of defense enzymes, defense genes, and plant semaphorins, which may further contribute to increased plant resistance. Based on the activity experiments and molecular dockings, the indole core structure may be the foundation of these compounds' anti-G. cichoracearum activity. Among them, the indole derivative parent structures of compounds 6, 7, and 9 exhibit strong effects. Moreover, the methoxy substitution in compound 7 can enhance their activity. By isolating and structurally identifying the above indole alkaloids, new candidates for anti-powdery mildew chemical screening were discovered, which could enhance the utilization of N. tabacum-derived fungi in pesticide development.


Assuntos
Alcaloides , Aspergillus fumigatus , Neopreno , Nicotiana , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/química , Alcaloides/farmacologia
5.
Cryobiology ; 111: 96-103, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37121387

RESUMO

This study focused on the biomechanical properties and microstructural changes in dentin of teeth in different age groups after cryopreserved for different durations. Ninety third molars from three age groups (youth group, middle-age group, and elderly group), were collected and randomly divided into three groups according to freezing time at -196 °C (7 days, 30 days, and 90 days). Control group was shored at ordinary temperature. After rewarming, the compressive strength and elastic modulus of the dentin were measured with an electronic universal tester. Scanning electron microscopy was used to evaluate the microstructure of dentin after cryopreservation. After cryopreservation, the compressive strength of the teeth in each experimental group was not significantly different from control group. With the increase of freezing time and age, dentin's elastic modulus showed a decreasing trend. There were statistically significances between the control group and freezing 90d group, freezing 7d and 90d group, youth and middle-aged group, youth and elderly group (P < 0.05). Both freezing time and age factors were significant for the elastic modulus of dentin(P<0.05). There was no interaction effect for age and freezing time. In transverse sections of scanning electron microscopy, the dentinal tubule became narrower, partially occluded, and more easily adhered to impurities in the long freezing time and elderly group. In longitudinal sections, with freezing time and age, the inner wall of the dentinal tubules became rough especially in the aged group cryopreserved for 90 days. No significant microcracks exited in any of the longitudinal sections of dentin.


Assuntos
Criopreservação , Dentina , Humanos , Idoso , Pessoa de Meia-Idade , Adolescente , Lactente , Criopreservação/métodos , Dentina/química , Congelamento , Microscopia Eletrônica de Varredura
6.
J Am Chem Soc ; 144(16): 7283-7294, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35420800

RESUMO

Multidrug resistance to chemotherapeutic drugs is one of the major causes for the failure of cancer treatment. Therefore, there is an urgent need to develop anticancer agents that can combat multidrug-resistant cancers effectively and mitigate drug resistance. Here, we report a rational design of anticancer heterochiral ß-peptide polymers as synthetic mimics of host defense peptides to combat multidrug-resistant cancers. The optimal polymer shows potent and broad-spectrum anticancer activities against multidrug-resistant cancer cells and is insusceptible to anticancer drug resistance owing to its membrane-damaging mechanism. The in vivo study indicates that the optimal polymer efficiently inhibits the growth and distant transfer of solid tumors and the metastasis and seeding of circulating tumor cells. Moreover, the polymer shows excellent biocompatibility during anticancer treatment on animals. In addition, the ß-peptide polymers address those prominent shortcomings of anticancer peptides and have superior stability against proteolysis, easy synthesis in large scale, and low cost. Collectively, the structural diversity and superior anticancer performance of ß-peptide polymers imply an effective strategy in designing and finding anticancer agents to combat multidrug-resistant cancers effectively while mitigating drug resistance.


Assuntos
Antineoplásicos , Neoplasias , Animais , Peptídeos Catiônicos Antimicrobianos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Neoplasias/tratamento farmacológico , Polímeros/química , Polímeros/farmacologia
7.
Anal Chem ; 94(40): 13913-13920, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36166257

RESUMO

A signaling strategy can directly determine the analytical performance and application scope of photoelectrochemical (PEC) immunoassays, so it is of great significance to develop an effective signaling strategy. The electro-Fenton reaction has been extensively used to degrade organic pollutants, but it has not been applied to PEC immunoassays. Herein, we report a novel signaling strategy for a PEC immunoassay based on electro-Fenton degradation of liposomes (Lip) on a photoelectrode. Lip vesicles are coated on Au@TiO2 core-shell photoactive material, which can prevent ascorbic acid (AA) from scavenging photogenerated holes. In the presence of a target, the immunomagnetic bead labels are converted to Fe3+ for electro-Fenton reaction, and hydroxyl radicals generated by the electro-Fenton reaction can degrade the Lip vesicles on the photoelectrode. Because of the degradation of Lip vesicles, photogenerated holes can be scavenged more effectively by AA, leading to an increase in photocurrent. Based on the electro-Fenton-regulated interface electron transfer, the sensitive "signal on" PEC immunoassay of a carcinoembryonic antigen is achieved, which features a dynamic range from 0.05 to 5 × 104 pg mL-1 and a detection limit of 0.01 pg mL-1. Our work provides a novel and efficient PEC immunoassay platform by introducing the electro-Fenton reaction into PEC analysis.


Assuntos
Técnicas Biossensoriais , Poluentes Ambientais , Ácido Ascórbico , Antígeno Carcinoembrionário/análise , Técnicas Eletroquímicas , Poluentes Ambientais/análise , Imunoensaio , Limite de Detecção , Lipossomos , Polímeros
8.
Chemistry ; 28(65): e202202226, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-35996361

RESUMO

The high-mortality invasive fungal infections seriously threaten the lives of immunocompromised people. Host defense peptides and cell-penetrating peptides are representative membrane-active peptides with different functions. Among them, host defense peptides mimicking is a valid strategy in the design of synthetic antifungal agents. Despite the brilliance in the field of intracellular delivery, the potential of cell-penetrating peptides and their mimics for designing antifungal agents has been overlooked. In this concept article, we describe the structural design of synthetic antifungal polymers as mimics of host defense peptides, and highlight the effectiveness and potential of cell-penetrating peptide-inspired strategy in designing potent and selective antifungal polymeric agents. In addition, an outlook for further expanding the design horizons of antifungal polymers is also presented.


Assuntos
Antifúngicos , Peptídeos Penetradores de Células , Humanos , Antifúngicos/farmacologia , Antifúngicos/química , Testes de Sensibilidade Microbiana , Peptídeos Penetradores de Células/química , Peptídeos Catiônicos Antimicrobianos , Polímeros
9.
Macromol Rapid Commun ; 43(23): e2200575, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35978269

RESUMO

Hybrid peptides with heterogeneous backbone are a class of peptide mimics with adjustable proteolytic stability obtained from incorporating unnatural amino acid residues into peptide backbone. α/ß-peptides and peptide/peptoid hybrids are two types of hybrid peptides that are widely studied for diverse applications, and several synthetic methods have been developed. In this mini review, the advance in hybrid peptide synthesis is summarized, including solution-phase method, solid-phase method, and novel polymerization method. Conventional solution-phase method and solid-phase method generally result in oligomers with defined sequences, while polymerization methods have advantages in preparing peptide hybrid polymers with high molecular weight with simple operation and low cost. In addition, the future development of polymerization method to realize the control of the peptide hybrid polymer sequence is discussed.


Assuntos
Peptoides , Peptoides/química , Peptídeos/química , Sequência de Aminoácidos , Polimerização , Polímeros/química
10.
J Clin Periodontol ; 49(11): 1192-1202, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35924763

RESUMO

AIM: The role of lipids in periodontitis has not been well studied. Thus, this study aimed to explore periodontitis-associated lipid profile changes and identify differentially expressed lipid metabolites in gingival tissues. MATERIALS AND METHODS: Gingival tissues from 38 patients with periodontitis (periodontitis group) and 38 periodontally healthy individuals (control group) were collected. A ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry-based non-targeted metabolomics platform was used to identify and compare the lipid profiles of the two groups. The distribution and expression of related proteins were subsequently analysed via immunohistochemistry to further validate the identified lipids. RESULTS: Lipid profiles significantly differed between the two groups, and 20 differentially expressed lipid species were identified. Lysophosphatidylcholines (lysoPCs), diacylglycerols (DGs), and phosphatidylethanolamines (PEs) were significantly up-regulated, while triacylglycerols (TGs) were downregulated in the periodontitis group. Moreover, the staining intensity of ABHD5/CGI-58, secretory phospholipase A2 (sPLA2), and sPLA2-IIA was significantly stronger in the gingival tissues of patients with periodontitis than in those of healthy controls. CONCLUSIONS: LysoPCs, DGs, and PEs were significantly up-regulated, whereas TGs were down-regulated in gingival tissues of patients with periodontitis. Correspondingly, the immunohistochemical staining of ABHD5/CGI-58, sPLA2, and sPLA2-IIA in gingival tissues was consistent with the downstream production of lipid classes (lysoPCs, TGs, and DGs).


Assuntos
Periodontite , Fosfolipases A2 Secretórias , 1-Acilglicerol-3-Fosfato O-Aciltransferase , Diglicerídeos , Humanos , Lipidômica , Lisofosfatidilcolinas , Fosfatidiletanolaminas , Triglicerídeos
11.
Ecotoxicol Environ Saf ; 241: 113742, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35679726

RESUMO

The application of plastic mulch films brings convenience to agricultural production, but also causes plastic waste that can be degraded into microplastics (MPs). However, little is known about the fate of plastic waste in agricultural ecosystem under freeze-thaw alternation in middle and high latitudes, as well as in highlands around the world. Whether the release of plasticizers, i.e. phthalate esters (PAEs), under such conditions would pose a potential risk to exposed organisms due to bioaccumulation is also unknown. To fill these data gaps, the agricultural fields in Liaoning of China with typical freeze-thaw alternation was selected as the study area. The transformation of plastic film was demonstrated by simulation freeze-thaw alternating from -30 to 20 â„ƒ. Soil samples were collected to investigate the patterns of MP composition, abundance, and distribution. Concurrently, the concentrations of two PAEs including bis(2-ethylhexyl) phthalate (DEHP) and diethyl phthalate (DEP) in soils were analyzed to provide information on the correlation between MPs abundance and PAEs concentrations as well as potential risks. The results showed that freeze-thaw alternating can accelerate the formation of MPs and release of PAEs from plastic waste. The abundance of MPs was positively correlated with the concentration of PAEs. Soil PAEs ranged from 3268 ± 213-6351 ± 110 µg/kg, indicating that over 40 % of the PAEs were transferred from plastic films to soils. Such residual amounts could pose risk for exposed organisms. Hence, the current study suggested that special concerns should be given to the release plasticizers in plastic waste of agricultural soils.


Assuntos
Ácidos Ftálicos , Poluentes do Solo , China , Dibutilftalato , Ecossistema , Ésteres , Plastificantes/análise , Plásticos , Solo , Poluentes do Solo/análise
12.
BMC Ophthalmol ; 21(1): 392, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34781932

RESUMO

PURPOSE: To investigate the macular vessel density and thickness in macular-on rhegmatogenous retinal detachment (RRD) after vitrectomy with gas and silicone oil (SO) tamponade. METHODS: Patients with macular-on RRD eyes, treated with a single successful vitrectomy with gas or SO tamponade and a minimum 30 months follow-up, were reviewed. Best-corrected visual acuity (BCVA), macular vessel density and retinal thickness by using optical coherence tomography angiography, were compared to the contralateral eyes. RESULTS: Sixteen eyes with gas tamponade and 17 eyes with SO tamponade were included in the study. LogMAR best-corrected visual acuity (BCVA) slightly improved from 0.25 ± 0.18 (Snellen 20/36) to 0.17 ± 0.23 (Snellen 20/30) in eyes with gas tamponade, and decreased from 0.30 ± 0.22 (Snellen 20/40) to 0.49 ± 0.28 (Snellen 20/62) in eyes with SO tamponade. The parafoveal vessel densities in superficial vascular complex (SVC) and the corresponding inner retinal thickness (IRT) were similar between the affected eyes and the contralateral eyes in gas tamponade group (P = 0.578, P = 0.943), while significantly reduced in the affected eyes, compared to the contralateral eyes in SO tamponade group (P < 0.001, P < 0.001). CONCLUSION: Eyes in SO tamponade group had worse BCVA, lower SVC vessel densities and thinner corresponding IRT after vitrectomy for macular-on RRD, than those in gas tamponade group.


Assuntos
Macula Lutea , Descolamento Retiniano , Tamponamento Interno , Humanos , Descolamento Retiniano/cirurgia , Óleos de Silicone , Vitrectomia
13.
J Environ Sci (China) ; 105: 150-162, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34130832

RESUMO

Eco-toxicity investigation of polymer materials was considered extremely necessary for their potential menace, which was widely use as mulching materials in agricultural. In this study, polyethylene (PE), polystyrene (PS) and synthetic biomaterials-Ecoflex and cellulose were applying into soil cultivated with two potential indicator plants species: oat (Avena sativa) and red radish (Raphanus sativum). Variety of chemical, biochemical parameters and enzyme activity in soil were proved as effective approach to evaluate polymers phytotoxicity in plant-soil mesocosm. The F-value of biomass, pH, heavy metal and electoral conductivity of Raphanus behaved significant different from T0. Significant analysis results indicated biodegradation was fast in PE than PS, besides, heavy metals were dramatically decrease in the end implied the plant absorption may help decrease heavy metal toxicity. The increase value at T2 of Dehydrogenase activity (0.84 higher than average value for Avena & 0.91 higher for Raphanus), Metabolic Index (3.12 higher than average value for Avena & 3.81 higher for Raphanus) means during soil enzyme activity was promoted by biodegradation for its heterotrophic organisms' energy transportation was stimulated. Statistics analysis was carried on Biplot PC1 (24.2% of the total variance), PC2 (23.2% of the total variance), versus PC3 (22.8% of the total variance), which indicated phosphatase activity and metabolic index was significant correlated, and high correlation of ammonium and protease activity. Furthermore, the effects were more evident in Raphanus treatments than in Avena, suggesting the higher sensitivity of Raphanus to polymers treatment, which indicate biodegradation of polymers in Raphanus treatment has produced intermediate phytotoxic compounds.


Assuntos
Raphanus , Poluentes do Solo , Biodegradação Ambiental , Polímeros/toxicidade , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
14.
Langmuir ; 36(11): 2901-2910, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32114762

RESUMO

In the treatment of coronary artery disease (CAD), the use of stent implantation often leads to clinical complications such as restenosis, delayed endothelial healing, and thrombosis. Here, we develop a double drug sustained-release coating for the stent surface by grafting heparin/NONOate nanoparticles (Hep/NONOates). The Hep/NONOates and surface modification of the stent were characterized by X-ray photoelectron spectroscopy, attenuated total reflection Fourier-transform infrared spectroscopy, static water contact angle, and scanning electron microscopy (SEM), and the release behaviors of the anticoagulant, heparin (Hep) and the bioactive molecule, nitric oxide (NO) were studied. Furthermore, the blood compatibility and cytotoxicity of the modified stent were evaluated by whole blood adhesion and platelet adhesion tests, hemolysis assay, morphological changes of red blood cells, plasma recalcification time assay, in vitro coagulation time tests, and MTT assay. Finally, the results of a rabbit carotid artery stent implantation experiment showed that the double drug sustained-release coating for the stent can accelerate regeneration of endothelial cells and keep good anticoagulant activity. This study can provide new design ideas based on nanotechnology for improving the safety and effectiveness of drug-eluting stents.


Assuntos
Anticoagulantes/uso terapêutico , Stents Farmacológicos , Heparina/uso terapêutico , Nanopartículas/química , Doadores de Óxido Nítrico/uso terapêutico , Compostos Nitrosos/uso terapêutico , Animais , Anticoagulantes/química , Anticoagulantes/toxicidade , Aterosclerose/terapia , Artérias Carótidas/cirurgia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Materiais Revestidos Biocompatíveis/toxicidade , Heparina/química , Heparina/toxicidade , Nanopartículas/toxicidade , Doadores de Óxido Nítrico/química , Doadores de Óxido Nítrico/toxicidade , Compostos Nitrosos/química , Compostos Nitrosos/toxicidade , Coelhos
15.
Anal Bioanal Chem ; 412(4): 861-870, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31865416

RESUMO

In this paper, we report the use of a smartphone and B, N, and S co-doped carbon dots (BNS-CDs) as a promising peroxidase mimic to quantify hydrogen peroxide (H2O2). The synthesized BNS-CDs exhibited excellent peroxidase-like activity to catalyze the reaction of the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) with H2O2 to generate a blue oxide product (ox-TMB) with maximum absorption at 652 nm. Steady-state kinetic analysis demonstrated that the BNS-CDs showed much higher affinity than natural horseradish peroxidase (HRP) for H2O2 due to their small size and larger specific surface area. A smartphone colorimetric readout device was employed to record the RGB (red green blue) value of the ox-TMB solution via the Android application Color Grab for quantitative detection. A good linear relationship (R2 = 0.9970) between the H2O2 concentration and |R-Rblank| value was obtained in the range of 3-30 µM with a limit of detection (LOD) of 0.8 µM. The current method was successfully applied to determine H2O2 in mouthwash and milk with recoveries of 92.70-108.30%. The developed assay is a promising portable detection platform for H2O2 with good sensitivity and selectivity, simple operation, fast response, and low cost. Graphical abstract.


Assuntos
Carbono/química , Colorimetria/instrumentação , Peróxido de Hidrogênio/análise , Leite/química , Antissépticos Bucais/análise , Animais , Benzidinas/química , Materiais Biomiméticos/química , Catálise , Desenho de Equipamento , Análise de Alimentos/instrumentação , Limite de Detecção , Peroxidase/química , Smartphone/instrumentação
16.
Int Arch Allergy Immunol ; 178(3): 229-237, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30408809

RESUMO

BACKGROUND: Cellulose powder (CP) has been reported as a safe and effective complementary treatment for allergic rhinitis (AR). Currently, CP has gained increasing application for clinical management worldwide, particularly in China. However, studies focusing on the effect of CP on normal human nasal epithelial cells (hNECs) and ciliary function are lacking. Here, we aimed to explore the adverse effects of CP on the activity and ciliary function of hNECs. METHODS: We biopsied ethmoid sinus or middle turbinate tissues during surgical resection from control subjects who underwent endoscopic sinus surgery for diseases other than AR. Cells were isolated and passaged, followed by differentiation in an air-liquid interface (ALI). Flow cytometry and cell viability test (cell counting kit-8) were performed to detect the cytotoxicity of CP (effects on cell proliferation) on normal hNECs. By using the ALI culture model, we investigated the effects of CP on ciliary beat frequency (CBF). RESULTS: There was a significant reduction in hNEC count at high concentrations of CP (2.5 mg/mL) at days 3 and 7 (both p < 0.05). As the concentration increased, cell death increased progressively from day 3 to day 7. However, these effects were not evident at low concentrations (0.25 mg/mL, p > 0.05). High-dose CP (2.5 mg) significantly reduced the CBF (p < 0.05). At lower concentrations (0.25-2.5 mg/mL), CP initially increased but subsequently reduced the CBF of hNECs compared with control group. CONCLUSIONS: Cytotoxicity and the suppression of ciliary beat at high concentrations justify more prudent use of CP for the management of AR.


Assuntos
Celulose/farmacologia , Cílios/efeitos dos fármacos , Mucosa Nasal/efeitos dos fármacos , Adulto , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Celulose/efeitos adversos , Celulose/uso terapêutico , Cílios/fisiologia , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Feminino , Humanos , Masculino , Pós , Rinite Alérgica/tratamento farmacológico
17.
Mol Pharm ; 16(5): 1929-1938, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-30916972

RESUMO

Rattle-type nanostructures with movable cores, porous shells, and hollow interiors have become attractive nanoplatforms in the field of nanomedicine, especially for targeted and stimuli-responsive drug delivery. In this work, rattle-type gold nanorods@void@porous-SiO2 (GVPS) nanocomposites were fabricated facilely using the surface-protecting etching method and exhibited high photothermal conversion efficiency. Taking advantage of the porous shell and hollow interior, the nanocomposites have abundant space for drug loading and successfully improved the drug loading capacity up to ∼19.6%. To construct a multifunctional drug delivery system, GVPS was further functionalized with polyethylene glycol (PEG) and cyclic RGD peptides to improve biocompatibility as well as selectivity toward the targeted cancer cells. Besides, to achieve precise regulation and near-infrared laser activation of the drug release, a phase-changing material, 1-tetradecanol (1-TD, Tm: 39 °C), was employed as gatekeepers in this system. After incubation with an αVß3 integrin receptor-overexpressed cell line, the as-prepared GVPSPR-DOX/TD nanocomposites exhibited great performances in combined photothermal therapy and chemotherapy. It is worth noting that the combined therapy showed superior efficiency in cancer cell killing to chemotherapy or photothermal therapy alone.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Ouro/química , Raios Infravermelhos , Nanocompostos/química , Nanotubos/química , Neoplasias/tratamento farmacológico , Fotoquimioterapia/métodos , Dióxido de Silício/química , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos/efeitos da radiação , Células HeLa , Humanos , Integrina alfaVbeta3/metabolismo , Células MCF-7 , Nanomedicina/métodos , Neoplasias/patologia , Peptídeos Cíclicos/química , Polietilenoglicóis/química , Porosidade
18.
Appl Microbiol Biotechnol ; 103(6): 2483-2492, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30685813

RESUMO

Ionic liquids (ILs) have been applied as an environmentally friendly solvent in the pretreatment of lignocellulosic biomass for more than a decade. The ILs involved pretreatment processes for cellulases mediated saccharification lead to both the breakdown of cellulose crystallinity and the decrease of lignin content, thereby improving the solubility of cellulose and the accessibility of cellulase. However, most cellulases are partially or completely inactivated in the presence of even low amount of ILs. Immobilized cellulases are found to perform improved stability and higher apparent activity in practical application compared with its free counterparts. Enzyme immobilization therefore has become a promising way to relieve the deactivation of cellulase in ILs. Various immobilization carriers and methods have been developed and achieved satisfactory results in improving the stability, activity, and recycling of cellulases in IL pretreatment systems. This review aims to provide detailed introduction of immobilization methods and carrier materials of cellulase, including natural polysaccharides, synthetic polymers, inorganic materials, magnetic materials, and newly developed composite materials, and illustrate key methodologies in improving the performance of cellulase in the presence of ILs. Especially, novel materials and concepts from the recently representative researches are focused and discussed comprehensively, and future trends in immobilization of cellulases in non-natural ILs environments are speculated in the end.


Assuntos
Celulase/metabolismo , Enzimas Imobilizadas/metabolismo , Líquidos Iônicos/química , Biomassa , Celulose/metabolismo , Hidrólise , Lignina/metabolismo , Polissacarídeos/química , Solventes
19.
Anal Chem ; 90(19): 11696-11702, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30175585

RESUMO

Nanozymes have emerged as promising alternatives to overcome the high cost and low stability of natural enzymes. Nanozymes with peroxidase-like activities have been studied to construct versatile biosensors by using specific biorecognition ligands (such as enzymes, antibodies, and aptamers) or molecularly imprinted polymers (MIPs). However, the use of bioligands compromises the high stability and low cost promise of nanozymes, while the MIPs may not be applicable to multiplex detection. To address these limitations, here we constructed the nanozyme sensor arrays based on peroxidase-like Pt, Ru, and Ir nanozymes. The cross-reactive nanozyme sensor arrays were successfully used for the detection of biothiols and proteins as well as the discrimination of cancer cells because of the differential nonspecific interactions between the components of the sensor arrays and the analytes. The usefulness of the nanozyme sensor arrays was further validated by the detection of blind unknown samples, where 28 of 30 biothiols and 42 of 45 proteins were correctly identified. Moreover, the practical application of the nanozyme sensor arrays was demonstrated by the successful discrimination of biothiols in serum and proteins in human urine.


Assuntos
Materiais Biocompatíveis/metabolismo , Técnicas Biossensoriais/métodos , Proteínas/análise , Compostos de Sulfidrila/análise , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Complexos de Coordenação/química , Complexos de Coordenação/metabolismo , Análise Discriminante , Glutationa/análise , Humanos , Impressão Molecular , Peroxidase/química , Peroxidase/metabolismo , Platina/química , Polímeros/química , Albumina Sérica/análise
20.
Bioconjug Chem ; 29(12): 4062-4071, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30404438

RESUMO

Copper sulfide (CuS) nanoparticles have been considered one of the most clinical relevant nanosystems because of their straightforward chemistry, small particle size, low toxicity, and intrinsic theranostic characteristics. In our previous studies, radioactive [64Cu]CuS nanoparticles were successfully developed to be used as efficient radiotracers for positron emission tomography and for photothermal ablation therapy of cancer cells using near-infrared laser irradiation. However, the major challenge of CuS nanoparticles as a theranostic platform is the lack of a means for effective targeted delivery to the tumor site. To overcome this challenge, we designed and synthesized angiogenesis-targeting [64Cu]CuS nanoparticles, which are coupled with cyclic RGDfK peptide [c(RGDfK)] through polyethylene glycol (PEG) linkers using click chemistry. In assessing their tumor-targeting efficacy, we found that the tumor uptakes of [64Cu]CuS-PEG-c(RGDfK) nanoparticles at 24 h after intravenous injection were significantly greater (8.6% ± 1.4% injected dose/gram of tissue) than those of nontargeted [64Cu]CuS-PEG nanoparticles (4.3% ± 1.2% injected dose/gram of tissue, p < 0.05). Irradiation of tumors in mice administered [64Cu]CuS-PEG-c(RGDfK) nanoparticles induced 98.7% necrotic areas. In contrast, irradiation of tumors in mice administered nontargeted CuS-PEG nanoparticles induced 59% necrotic areas ( p < 0.05). The angiogenesis-targeting [64Cu]CuS nanoparticles may serve as a promising platform for image-guided ablation therapy with high efficacy and minimal side effects in future clinical translation of this novel class of multifunctional nanomaterials.


Assuntos
Radioisótopos de Cobre/química , Cobre/química , Integrina alfaVbeta3/química , Terapia a Laser , Nanopartículas Metálicas/química , Neoplasias Experimentais/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Animais , Células HEK293 , Humanos , Camundongos , Peptídeos Cíclicos/química , Polietilenoglicóis/química
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