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1.
Angew Chem Int Ed Engl ; 63(30): e202403241, 2024 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-38710651

RESUMO

Exocytosis involving the fusion of intracellular vesicles with cell membrane, is thought to be modulated by the mechanical cues in the microenvironment. Single-cell electrochemistry can offer unique information about the quantification and kinetics of exocytotic events; however, the effects of mechanical force on vesicular release have been poorly explored. Herein, we developed a stretchable microelectrode with excellent electrochemical stability under mechanical deformation by microfabrication of functionalized poly(3,4-ethylenedioxythiophene) conductive ink, which achieved real-time quantitation of strain-induced vesicular exocytosis from a single cell for the first time. We found that mechanical strain could cause calcium influx via the activation of Piezo1 channels in chromaffin cell, initiating the vesicular exocytosis process. Interestingly, mechanical strain increases the amount of catecholamines released by accelerating the opening and prolonging the closing of fusion pore during exocytosis. This work is expected to provide revealing insights into the regulatory effects of mechanical stimuli on vesicular exocytosis.


Assuntos
Células Cromafins , Exocitose , Células Cromafins/metabolismo , Microeletrodos , Animais , Microtecnologia/métodos , Cálcio/metabolismo , Estresse Mecânico , Polímeros/química , Compostos Bicíclicos Heterocíclicos com Pontes/química
2.
J Clin Pediatr Dent ; 47(6): 142-149, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37997245

RESUMO

The aim was to investigate the relationship between time to hemostasis and pulpotomy outcomes with the use of iRoot BP Plus (Innovative Bioceramics, Vancouver, Canada) for young permanent teeth of patients aged from 7 to 12 with symptomatic irreversible pulpitis and evaluate the outcomes of pulpotomy. The present study was a prospective cohort study. Two hundred and six young permanent teeth with symptomatic irreversible pulpitis underwent pulpotomy with the use of iRoot BP Plus. All patients underwent pulpotomy in accordance with a standardized protocol. Patients were postoperatively re-called after 3, 6, 12 months. Successful cases were defined according to clinical and radiographic evaluations. Main outcome measures included tooth position, cave shape, previous restoration, preoperative symptoms, time to hemostasis and outcomes. On the basis of univariate linear regression model, the relationships between time to hemostasis was evaluated, and p < 0.05 indicated a difference that achieved statistical significance. One hundred and ninety-three teeth can be evaluated after a follow-up for 6 to 36 months. The mean age of subjects was 9.43 ± 1.51 years. The overall clinical and radiographic success rate of pulpotomy reached 71.5% (138/193). After adjusting potential confounders (age, sex, previous restoration), non-linear relationship was detected between time to hemostasis and pulpotomy outcomes whose point was 4 minutes. The relationship between time to hemostasis and pulpotomy outcomes is non-linear. Pulpotomy outcomes was negatively related with time to hemostasis when time to hemostasis is more than 4 minutes.


Assuntos
Pulpite , Pulpotomia , Humanos , Criança , Pulpotomia/métodos , Compostos de Cálcio , Estudos Prospectivos , Pulpite/cirurgia , Silicatos , Hemostasia , Resultado do Tratamento , Óxidos
3.
Zhongguo Zhong Yao Za Zhi ; 48(22): 6075-6081, 2023 Nov.
Artigo em Zh | MEDLINE | ID: mdl-38114214

RESUMO

With the continuous exploration of microemulsions as solvents for traditional Chinese medicine extraction, polyoxyethy-lene(35) castor oil(CrEL), a commonly used surfactant, is being utilized by researchers. However, the problem of detecting residues of this surfactant in microemulsion extracts has greatly hampered the further development of microemulsion solvents. Based on the chemical structures of the components in CrEL and the content determination method of castor oil in the 2020 edition of the Chinese Pharmacopoeia(Vol. Ⅳ), this study employed gas chromatography(GC) and single-factor experiments to optimize the preparation method of methyl ricinoleate from CrEL. The conversion coefficient between the two was validated, and the optimal sample preparation method was used to process microemulsion extracts of Zexie Decoction from three batches. The content of methyl ricinoleate generated was determined, and the content of CrEL in the microemulsion extracts of Zexie Decoction was calculated using the above conversion coefficient. The results showed that the optimal preparation method for CrEL was determined. Specifically, 10 mL of 1 mol·L~(-1) KOH-methanol solution was heated at 60 ℃ for 15 min in a water bath. Subsequently, 10 mL of boron trifluoride etherate-methanol(1∶3) solution was heated at 60 ℃ for 15 min in a water bath, followed by extraction with n-hexane twice. CrEL could stably produce 20.84% methyl ricinoleate. According to this conversion coefficient, the average mass concentration of CrEL in the three batches of Zexie Decoction microemulsion extracts was 11.94 mg·mL~(-1), which was not significantly different from the CrEL mass concentration of 11.57 mg·mL~(-1) during microemulsion formulation, indicating that the established content determination method of this study was highly accurate, sensitive, and repeatable. It can be used for subsequent research on microemulsion extracts of Zexie Decoction and provide a reference for quality control of other drug formulations containing CrEL.


Assuntos
Óleo de Rícino , Polietilenoglicóis , Polietilenoglicóis/química , Metanol , Tensoativos/química , Solventes , Água/química , Emulsões/química
4.
J Integr Plant Biol ; 64(7): 1364-1373, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35442564

RESUMO

Here, through single-molecule real-time sequencing, we present a high-quality genome sequence of the Japanese larch (Larix kaempferi), a conifer species with great value for wood production and ecological afforestation. The assembled genome is 10.97 Gb in size, harboring 45,828 protein-coding genes. Of the genome, 66.8% consists of repeat sequences, of which long terminal repeat retrotransposons are dominant and make up 69.86%. We find that tandem duplications have been responsible for the expansion of genes involved in transcriptional regulation and stress responses, unveiling their crucial roles in adaptive evolution. Population transcriptome analysis reveals that lignin content in L. kaempferi is mainly determined by the process of monolignol polymerization. The expression values of six genes (LkCOMT7, LkCOMT8, LkLAC23, LkLAC102, LkPRX148, and LkPRX166) have significantly positive correlations with lignin content. These results indicated that the increased expression of these six genes might be responsible for the high lignin content of the larches' wood. Overall, this study provides new genome resources for investigating the evolution and biological function of conifer trees, and also offers new insights into wood properties of larches.


Assuntos
Larix , Larix/genética , Larix/metabolismo , Lignina/genética , Lignina/metabolismo , Árvores/metabolismo , Madeira/genética
5.
Surg Radiol Anat ; 44(4): 551-558, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35303119

RESUMO

OBJECTIVES: The purpose of this study was to investigate short- and long-term postoperative changes of both morphology and transverse stability in mandibular ramus after intraoral vertical ramus osteotomy (IVRO) in patients with jaw deformity using three-dimensional (3D) orthognathic surgery planning treatment software for measurement of distances and angles. STUDY DESIGN: This retrospective study included consecutive patients with skeletal Class III malocclusion who had undergone intraoral vertical ramus osteotomy and computed tomography images before (T0), immediately after (T1), and 1 year after (T2) surgery. Reference points, reference lines and evaluation items were designated on the reconstructed 3D surface models to measure distances, angles and volume. The average values at T0, T1, T2 and time-dependent changes in variables were obtained. RESULTS: After surgery, the condylar length, ramal height, mandibular body length and mandibular ramus volume were significantly decreased (P < 0.01), while clinically insignificant change was observed from T1 to T2. The angular length was increased immediately after surgery (P < 0.05), but it was decreased 1 year after surgery (P < 0.05). Lateral ramal inclination showed significant increase after surgery (P < 0.05) and maintained at T2. CONCLUSION: Changes in the morphology of the mandibular ramus caused by IVRO do not obviously bring negative effect on facial appearance. Furthermore, despite position and angle of mandibular ramus changed after IVRO, good transverse stability was observed postoperatively. Therefore, IVRO technique can be safely used without compromising esthetic results.


Assuntos
Osteotomia Sagital do Ramo Mandibular , Prognatismo , Cefalometria/métodos , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Osteotomia Sagital do Ramo Mandibular/métodos , Prognatismo/cirurgia , Estudos Retrospectivos
6.
BMC Oral Health ; 22(1): 62, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260122

RESUMO

BACKGROUND: The application of calcium phosphate (CaP)-based bone substitutes plays an important role in periodontal regeneration, implant dentistry and alveolar bone reconstruction. The incorporation of strontium (Sr) into CaP-based bone substitutes appears to improve their biological properties, but the reported in vivo bone repair performance is inconsistent among studies. Herein, we conducted a systematic review and meta-analysis to investigate the in vivo performance of Sr-doped materials. METHODS: We searched PubMed, EMBASE (via OVIDSP), and reference lists to identify relevant animal studies. The search, study selection, and data extraction were performed independently by two investigators. Meta-analyses and sub-group analyses were conducted using Revman version 5.4.1. The heterogeneity between studies were assessed by I2. Publication bias was investigated through a funnel plot. RESULTS: Thirty-five studies were finally enrolled, of which 16 articles that reported on new bone formation (NBF) were included in the meta-analysis, covering 31 comparisons and 445 defects. The overall effect for NBF was 2.25 (95% CI 1.61-2.90, p < 0.00001, I2 = 80%). Eight comparisons from 6 studies reported the outcomes of bone volume/tissue volume (BV/TV), with an overall effect of 1.42 (95% CI 0.65-2.18, p = 0.0003, I2 = 75%). Fourteen comparisons reported on the material remaining (RM), with the overall effect being -2.26 (95% CI - 4.02 to - 0.50, p = 0.0009, I2 = 86%). CONCLUSIONS: Our study revealed that Sr-doped calcium phosphate bone substitutes improved in vivo performance of bone repair. However, more studies are also recommended to further verify this conclusion.


Assuntos
Substitutos Ósseos , Fosfatos de Cálcio , Animais , Substitutos Ósseos/uso terapêutico , Osso e Ossos , Fosfatos de Cálcio/uso terapêutico , Humanos , Estrôncio/uso terapêutico
7.
Angew Chem Int Ed Engl ; 61(26): e202203757, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35451556

RESUMO

Many cells in vivo have their inherent motions, which involve numerous biochemical and biophysical signals synergistically regulating cell behavior and function. However, existing methods offer little information about the concurrently chemical and physical responses of dynamically pulsing cells. Here, we report a soft electrode with an electrospun poly(3,4-ethylenedioxythiophene) (PEDOT)-based nanomesh to fully comply with spontaneous motions of cells. Moreover, this electrode demonstrated excellent electrical conductivity, electrochemical performance and cellular biocompatibility. Cardiomyocytes cultured thereon exhibited autonomous and rhythmic contractility, and synchronously induced mechanical deformation of the underlying electrode, which allowed real-time monitoring of nitric oxide release and electrophysiological activity of cardiomyocytes. This work provides a promising way toward recording chemical and electrical signals of biological systems with their natural motions.


Assuntos
Miócitos Cardíacos , Polímeros , Condutividade Elétrica , Eletrodos , Fenômenos Eletrofisiológicos
8.
AAPS PharmSciTech ; 22(3): 110, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33733385

RESUMO

This study sought to improve the oral bioavailability and enhance the anti-enteritis effect of fraxetin by incorporating it into long circulating liposomes (F-LC-Lipo). The optimal formulation of F-LC-Lipo was obtained via orthogonal design. The particle size, morphology, encapsulation efficiency, stability, and anti-enteritis effect of F-LC-Lipo were evaluated. The particle size of F-LC-Lipo was 166.65 ± 8.75 nm with entrapment efficiency (EE) of 92.18 ± 0.17%. The release rate in different dissolution media (pH 1.2 HCl, DDW, and pH 7.4 PBS) was significantly higher than that of fraxetin solution. Compared with the free fraxetin solution, F-LC-Lipo increased oral bioavailability of fraxetin by 4.43 times (443%). More importantly, F-LC-Lipo could improve the levels of interleukin-1 beta (IL-1ß), IL-6, malondialdehyde (MDA), superoxide dismutase (SOD), tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), prostaglandin E2 (PEG2), and IL-10 in rats with enteritis. Overall, these results suggested that LC-Lipo may serve as a potential carrier for improving the solubility and oral bioavailability of fraxetin as well as improving its enteritis effect.


Assuntos
Antioxidantes/administração & dosagem , Antioxidantes/uso terapêutico , Cumarínicos/administração & dosagem , Cumarínicos/uso terapêutico , Enterite/tratamento farmacológico , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/uso terapêutico , Disponibilidade Biológica , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Enterite/patologia , Lipossomos , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley
9.
Macromol Rapid Commun ; 40(17): e1800730, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30537429

RESUMO

A negative-charged, metal-containing cyclomatrix polyphosphazene microsphere (MCPM) is synthesized using the strategy of precipitation polymerization of di-functionalized polyoxometalates (POMs) and hexachlorocyclotriphosphazene. The chemical structure of these MCPMs is well characterized by 13 C MAS NMR and 31 P MAS NMR, as well as FT-IR, electron microscopy, and X-ray photoelectron spectroscopy. The covalent grafting of the rigid POMs clusters into the framework of these microspheres prevents the collapsing of the pores, making these MCPMs porous materials. Taking advantage of the porous structure and the negative charges in the frameworks, these materials show interesting charge-selective adsorption properties, as demonstrated by the selective adsorption of positive-charged dyes in comparison with negative-charged dyes.


Assuntos
Corantes/química , Microesferas , Compostos Organofosforados/química , Polímeros/química , Compostos de Tungstênio/química , Adsorção , Porosidade
10.
Acta Radiol ; 59(2): 212-220, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28509567

RESUMO

Background Radiation-induced parotid gland damage is a common complication of radiotherapy (RT) in patients with nasopharyngeal carcinoma (NPC), which always causes xerostomia, dysphagia, dental caries, and even sleep disorders. Early evaluation of radiation-induced parotid damage is required to facilitate early interventions. Purpose To early-evaluate radiation-induced parotid damage using diffusion kurtosis imaging (DKI) in patients with NPC undergoing RT. Material and Methods Thirty-two patients with NPC underwent DKI for parotid glands pre-RT (two weeks before RT), mid-RT (five weeks after RT began), and post-RT (four weeks after RT). Parotid volume, apparent diffusion coefficient (ADC), corrected diffusion coefficient (D), excess diffusion kurtosis coefficient (K) values, mean radiation dose, and xerostomia degrees were recorded and analyzed. Results During RT, parotid ADC (change rates = 41.3 ± 25.2% at mid-RT, 70.8 ± 34.3% at post-RT) and D (change rates = 41.9 ± 25.2% at mid-RT, 63.2 ± 30.2% at post-RT) increased, while parotid volume (atrophy rates = 31.5 ± 7.9% at mid-RT, 30.6 ± 10.3% at post-RT) and K (change rates = -17.8 ± 11.0% at mid-RT, -29.8 ± 9.0% at post-RT) decreased significantly (all P < 0.001). At post-RT, the change rate of parotid D values was significantly positively correlated with the mean radiation dose ( r = 0.455, P < 0.001). Parotid ADC, D, and K values showed excellent intra- and inter-observer agreement (intraclass correlation coefficient = 0.946-0.985). Conclusion Radiation-induced parotid damage in patients with NPC undergoing RT could be effectively evaluated by DKI in the early stage.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias Nasofaríngeas/complicações , Neoplasias Nasofaríngeas/radioterapia , Glândula Parótida/patologia , Glândula Parótida/efeitos da radiação , Adulto , Idoso , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Radioterapia/efeitos adversos , Dosagem Radioterapêutica
11.
Lasers Med Sci ; 33(4): 899-908, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29374364

RESUMO

Various flap graft techniques in the treatment of gingival recession have already been reported in the literatures for root coverage. Laser therapy has effects of ablative, hemostatic, and decontamination. Therefore, we performed a meta-analysis of randomized controlled trials (RCTs) to compare the efficacy of flap surgery combined with laser with surgery alone for treating gingival recession. The studies were searched from PubMed, Embase, Web of science, and the Cochrane Central Register of Controlled Trials by two reviewers up to August 2017. The quality of RCTs was assessed by Cochrane Handbook. Data were extracted from studies and analyzed by Review Manager 5.3. 95% confidence interval (CI) and risk ratio (RR) were calculated for dichotomous data. Seven RCTs with 173 patients and 296 teeth were included in the meta-analysis. We found no statistically significant differences between two groups in GRD (gingival recession depth) (P = 0.21), GRW (gingival recession width) (P = 0.92), RES (root esthetic score) (P = 0.21), and CRC (complete root coverage) (P = 0.09). Statistically significant differences were found between two groups in the WKT (width of keratinized tissue) (P < 0.0001) and 1-year follow-up of PD (probing depth) (P = 0.03) and CAL (clinical attachment level) (P < 0.00001). The meta-analysis found that surgery with laser therapy provided clinical advantages in terms of WKT and 1-year follow-up of PD and CAL. However, flap graft associated with laser did not offer additional benefit to root coverage and esthetics in treating gingival recession. More long-term studies are required to assess these parameters.


Assuntos
Retração Gengival/radioterapia , Gengiva/efeitos da radiação , Humanos , Terapia com Luz de Baixa Intensidade , Retalhos Cirúrgicos , Raiz Dentária/cirurgia , Resultado do Tratamento
12.
Biopolymers ; 107(8)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28422272

RESUMO

Aiming at understanding the molecular mechanism of the lignin dissolution in imidazolium-based ionic liquids (ILs), this work presents a combined quantum chemistry (QC) calculation and molecular dynamics (MD) simulation study on the interaction of the lignin model compound, veratrylglycerol-ß-guaiacyl ether (VG) with 1-allyl-3-methylimidazolium chloride ([Amim]Cl). The monomer of VG is shown to feature a strong intramolecular hydrogen bond, and its dimer is indicated to present important π-π stacking and intermolecular hydrogen bonding interactions. The interactions of both the cation and anion of [Amim]Cl with VG are shown to be stronger than that between the two monomers, indicating that [Amim]Cl is capable of dissolving lignin. While Cl- anion forms a hydrogen-bonded complex with VG, the imidazolium cation interacts with VG via both the π-π stacking and intermolecular hydrogen bonding. The calculated interaction energies between VG and the IL or its components (the cation, anion, and ion pair) indicate the anion plays a more important role than the cation for the dissolution of lignin in the IL. Theoretical results provide help for understanding the molecular mechanism of lignin dissolution in imidazolium-based IL. The theoretical calculations on the interaction between the lignin model compound and [Amim]Cl ionic liquid indicate that the anion of [Amim]Cl plays a more important role for lignin dissolution although the cation also makes a substantial contribution.


Assuntos
Compostos Alílicos/química , Imidazóis/química , Líquidos Iônicos/química , Lignina/química , Modelos Químicos , Ligação de Hidrogênio
13.
Sensors (Basel) ; 17(11)2017 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-29135928

RESUMO

Wearable sensors for detection of human activities have encouraged the development of highly elastic sensors. In particular, to capture subtle and large-scale body motion, stretchable and wide-range strain sensors are highly desired, but still a challenge. Herein, a highly stretchable and transparent stain sensor based on ionic liquids and elastic polymer has been developed. The as-obtained sensor exhibits impressive stretchability with wide-range strain (from 0.1% to 400%), good bending properties and high sensitivity, whose gauge factor can reach 7.9. Importantly, the sensors show excellent biological compatibility and succeed in monitoring the diverse human activities ranging from the complex large-scale multidimensional motions to subtle signals, including wrist, finger and elbow joint bending, finger touch, breath, speech, swallow behavior and pulse wave.


Assuntos
Dispositivos Eletrônicos Vestíveis , Atividades Humanas , Humanos , Líquidos Iônicos , Movimento (Física) , Polímeros
14.
Biomacromolecules ; 17(7): 2321-8, 2016 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-27251028

RESUMO

We previously reported the coassembly of various proteins with poly(4-vinylpyridine) (P4VP) to form core-shell nanoparticles (CSNPs). However, P4VP suffers from its cytotoxicity and in vivo toxicity, which prohibit it from many potential biomedical applications. Here, pyridine-grafted diblock copolymer poly(caprolactone-graft-pyridine)-block-poly(caprolactone) [P(CL-g-Py)-b-PCL] was prepared through a combination of ring-opening polymerization and Cu(I) catalyzed azide-alkyne cycloaddition reaction. CSNPs could be readily constructed by the self-assembly of transferrin (Tf) and P(CL-g-Py)-b-PCL, which showed a narrower range of particle sizes, improved stability, and higher loading capacity for anticancer drug doxorubicin (DOX), compared with similar particles prepared from the coassembly of Tf and P4VP. Additionally, the drug-loaded Tf/P(CL-g-Py)-b-PCL CSNPs could effectively target MCF7 cancer cells via the binding of Tf to transferrin receptors (TfR).


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Polímeros/química , Caproatos/química , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lactonas/química , Células MCF-7 , Estrutura Molecular , Polivinil/química , Receptores da Transferrina/metabolismo , Transferrina/química , Transferrina/metabolismo
15.
Biomacromolecules ; 15(4): 1346-54, 2014 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-24611557

RESUMO

Thiol-modified nanoparticles have potential applications in mucoadhesive drug delivery and have been examined in this regard for topical ocular delivery. In this paper we provide a simple method for the synthesis of a dithiol terminated amphiphilic diblock copolymer. Bidentate dithiol-poly(ethylene glycol)-poly(d,l-lactide) (SH2-PEG-PDLLA) was synthesized and micelles with dithiol-containing coronas were prepared from this block copolymer via the emulsion method. In vitro release studies indicated that the presence of the thiol groups at the surface did not affect the rate of release of dexamethasone, used as a representative ocular drug. The micelles also showed low cytotoxicity to human corneal epithelial cells (HCEC) and murine fibroblast cells (3T3 cells). A hydrophobic red fluorophore, Nile red, was loaded into the core of micelles and confocal microscopy was used to study HCEC uptake and retention of the micelles. The micelles were rapidly endocytosed by the HCEC, with intracellular micelle levels remaining unchanged with incubation times from 5 to 120 min. Interestingly, Nile red was eliminated significantly more slowly from HCECs treated with the thiolated micelles. These results suggest that these dithiolated micelles may be effective for topical ocular drug delivery.


Assuntos
Administração Oftálmica , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Polímeros/síntese química , Células 3T3/efeitos dos fármacos , Animais , Células Cultivadas , Dexametasona/administração & dosagem , Dexametasona/farmacocinética , Portadores de Fármacos/síntese química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Células Epiteliais/efeitos dos fármacos , Epitélio Corneano/citologia , Epitélio Corneano/efeitos dos fármacos , Corantes Fluorescentes/farmacocinética , Humanos , Camundongos , Micelas , Oxazinas/farmacocinética , Poliésteres/química , Polietilenoglicóis/química , Polímeros/química , Tolueno/análogos & derivados , Tolueno/química
16.
Environ Sci Pollut Res Int ; 31(33): 45875-45886, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38981966

RESUMO

The corrosion behavior of carbon steel under the coexistence of carbon dioxide and SRB was studied by means of corrosion weight loss, SEM, EDS, in situ pH test, and other methods. The results showed that Chloride ions, temperature, pH, and oxygen coexist with iron bacteria will affect the corrosion under the coexistence of CO2 and SRB, and SRB tends to grow in a favorable environment for itself, and the corrosion rate of X52N at 42 days is slightly higher than that at 21 days. However, the pitting depth increased sharply from 21.20 µm in 21 days to 39.79 µm in 42 days. So that the corrosion can be divided into two stages. First, SRB catalyze the dissolution of FeCO3, leading to local uniform corrosion. Second, SRB directly obtain electrons from the metal surface, resulting in local pitting. In addition, the environment under the stable mineralized biofilm was found to be slightly alkaline.


Assuntos
Dióxido de Carbono , Aço , Corrosão , Aço/química , Dióxido de Carbono/química , Biofilmes , Carbono/química
17.
J Hazard Mater ; 474: 134768, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38820749

RESUMO

Cadmium (Cd) and microplastics (MPs) gradually increased to be prevalent contaminants in soil, it is important to understand their combined effects on different soil-plant systems. We studied how different doses of polylactic acid (PLA) and polyethylene (PE) affected Cd accumulation, pakchoi growth, soil chemical and microbial properties, and metabolomics in two soil types. We found that high-dose MPs decreased Cd accumulation in plants in red soil, while all MPs decreased Cd bioaccumulation in fluvo-aquic soil. This difference was primarily attributed to the increase in dissolved organic carbon (DOC) and pH in red soil by high-dose MPs, which inhibited Cd uptake by plant roots. In contrast, MPs reduced soil nitrate nitrogen and available phosphorus, and weakened Cd mobilization in fluvo-aquic soil. In addition, high-dose PLA proved detrimental to plant health, manifesting in shortened shoot and root lengths. Co-exposure of Cd and MPs induced the shifts in bacterial populations and metabolites, with specific taxa and metabolites closely linked to Cd accumulation. Overall, co-exposure of Cd and MPs regulated plant growth and Cd accumulation by driving changes in soil bacterial community and metabolic pathways caused by soil chemical properties. Our findings could provide insights into the Cd migration in different soil-plant systems under MPs exposure. ENVIRONMENTAL IMPLICATION: Microplastics (MPs) and cadmium (Cd) are common pollutants in farmland soil. Co-exposure of MPs and Cd can alter Cd accumulation in plants, and pose a potential threat to human health through the food chain. Here, we investigated the effects of different types and doses of MPs on Cd accumulation, plant growth, soil microorganisms, and metabolic pathways in different soil-plant systems. Our results can contribute to our understanding of the migration and transport of Cd by MPs in different soil-plant systems and provide a reference for the control of combined pollution in the future research.


Assuntos
Cádmio , Microplásticos , Microbiologia do Solo , Poluentes do Solo , Cádmio/metabolismo , Cádmio/toxicidade , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Microplásticos/toxicidade , Microplásticos/metabolismo , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Poliésteres/metabolismo , Poliésteres/química , Polietileno/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Solo/química , Plantas/metabolismo , Plantas/efeitos dos fármacos
18.
ACS Biomater Sci Eng ; 10(8): 4878-4890, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39041681

RESUMO

The demand for macroporous hydrogel scaffolds with interconnected porous and open-pore structures is crucial for advancing research and development in cell culture and tissue regeneration. Existing techniques for creating 3D porous materials and controlling their porosity are currently constrained. This study introduces a novel approach for producing highly interconnected aspartic acid-gelatin macroporous hydrogels (MHs) with precisely defined open pore structures using a one-step emulsification polymerization method with surface-modified silica nanoparticles as Pickering stabilizers. Macroporous hydrogels offer adjustable pore size and pore throat size within the ranges of 50 to 130 µm and 15 to 27 µm, respectively, achieved through variations in oil-in-water ratio and solid content. The pore wall thickness of the macroporous hydrogel can be as thin as 3.37 µm and as thick as 6.7 µm. In addition, the storage modulus of the macroporous hydrogels can be as high as 7250 Pa, and it maintains an intact rate of more than 92% after being soaked in PBS for 60 days, which is also good performance for use as a biomedical scaffold material. These hydrogels supported the proliferation of human dental pulp stem cells (hDPSCs) over a 30 day incubation period, stretching the cell morphology and demonstrating excellent biocompatibility and cell adhesion. The combination of these desirable attributes makes them highly promising for applications in stem cell culture and tissue regeneration, underscoring their potential significance in advancing these fields.


Assuntos
Quitosana , Emulsões , Gelatina , Hidrogéis , Alicerces Teciduais , Gelatina/química , Hidrogéis/química , Humanos , Porosidade , Quitosana/química , Alicerces Teciduais/química , Emulsões/química , Células-Tronco/citologia , Aminoácidos/química , Proliferação de Células/efeitos dos fármacos , Polpa Dentária/citologia , Técnicas de Cultura de Células em Três Dimensões/métodos , Células Cultivadas , Técnicas de Cultura de Células/métodos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Engenharia Tecidual/métodos
19.
Adv Mater ; 36(19): e2312352, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38301140

RESUMO

Developing artificial ion transport systems, which process complicated information and step-wise regulate properties, is essential for deeply comprehending the subtle dynamic behaviors of natural channel proteins (NCPs). Here a photo-controlled logic-gated K+ channel based on single-chain random heteropolymers containing molecular motors, exhibiting multi-core processor-like properties to step-wise control ion transport is reported. Designed with oxygen, deoxygenation, and different wavelengths of light as input signals, complicated logical circuits comprising "YES", "AND", "OR" and "NOT" gate components are established. Implementing these logical circuits with K+ transport efficiencies as output signals, multiple state transitions including "ON", "Partially OFF" and "Totally OFF" in liposomes and cancer cells are realized, further causing step-wise anticancer treatments. Dramatic K+ efflux in the "ON" state (decrease by 50% within 7 min) significantly induces cancer cell apoptosis. This integrated logic-gated strategy will be expanded toward understanding the delicate mechanism underlying NCPs and treating cancer or other diseases is expected.


Assuntos
Apoptose , Luz , Humanos , Potássio/metabolismo , Potássio/química , Canais de Potássio/metabolismo , Linhagem Celular Tumoral , Ativação do Canal Iônico , Lipossomos/química , Lipossomos/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Lógica
20.
Front Chem ; 12: 1417763, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887698

RESUMO

Introduction: Facial nerve injury significantly impacts both the physical and psychological] wellbeing of patients. Despite advancements, there are still limitations associated with autografts transplantation. Consequently, there is an urgent need for effective artificial grafts to address these limitations and repair injuries. Recent years have witnessed the recognition of the beneficial effects of chitosan (CS) and graphene in the realm of nerve repair. Dental pulp stem cells (DPSCs) hold great promise due to their high proliferative and multi-directional differentiation capabilities. Methods: In this study, Graphene/CS (G/CST) composite tubes were synthesized and their physical, chemical and biological properties were evaluated, then DPSCs were employed as seed cells and G/CST as a scaffold to investigate their combined effect on promoting facial nerve injury repair. Results and Disscussion: The experimental results indicate that G/CST possesses favorable physical and chemical properties, along with good cyto-compatibility. making it suitable for repairing facial nerve transection injuries. Furthermore, the synergistic application of G/CST and DPSCs significantly enhanced the repair process for a 10 mm facial nerve defect in rabbits, highlighting the efficacy of graphene as a reinforcement material and DPSCs as a functional material in facial nerve injury repair. This approach offers an effective treatment strategy and introduces a novel concept for clinically managing facial nerve injuries.

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