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1.
Gels ; 10(9)2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39330152

RESUMO

The microstructure of bone consists of nano-hydroxyapatite (nano-HA) crystals aligned within the interspaces of collagen fibrils. To emulate this unique microstructure of bone, this work applied two biomimetic techniques to obtain bone-like microstructures in vitro, that is, combining the construction of collagen liquid crystal hydrogel (CLCH) with the application of a polymer-induced liquid precursor (PILP) mineralization process. Upon the elevation of pH, the collagen macromolecules within the collagen liquid crystal (CLC) were activated to self-assemble into CLCH, whose fibrils packed into a long and dense fiber bundle in high orientation, emulating the dense-packed matrix of bone. We demonstrated that the fibrillar mineralization of CLCH, leading to a bone-like nanostructured inorganic material part, can be achieved using the PILP crystallization process to pre-mineralize the dense collagen substrates of CLCH with CaCO3, immediately followed by the in situ mineral phase transformation of CaCO3 into weak-crystalline nano-HA. The combination of CLCH with the biomineralization process of PILP, together with the mineral phase transformation, achieved the in vitro simulation of the nanostructures of both the organic extracellular matrix (ECM) and inorganic ECM of bone. This design would constitute a novel idea for the design of three-dimension biomimetic bone-like material blocks for clinical needs.

2.
Sci Total Environ ; 954: 176382, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39304155

RESUMO

The capacitive deionization (CDI) has emerged as a robust technology due to its effective performance in removing and recovering phosphate in wastewater. However, there are still challenges in achieving fast charge transfer and high capacity phosphorus storage simultaneously. In this study, a layered double hydroxide-polyaniline-carbon nanotubes composite material (ZnFe-PANI/CNT) with heterojunction and pseudocapacitive characteristics was fabricated via a simple and effective precipitation strategy. The existence of heterojunction and pseudocapacitance of ZnFe-PANI/CNT was confirmed through material performance testing Moreover, with its fast charge transfer and high ion storage performance, it was achieved high phosphate adsorption efficiency (94 %) and sustainable electrode regeneration in low concentration phosphate wastewater. Ultraviolet photoelectron spectroscopy (UPS) and density functional theory revealed the ability to accelerate charge transfer, which was contributed by the heterojunction ZnFe-PANI/CNT. In addition, it was found that the synergies of electrostatic attraction, ligand exchange and surface complexation contributed to the high phosphate capture ability in the acidic environments. The binuclear bidentate or mononuclear bidentate structures dominated the surface configuration of phosphate adsorption at pH 4-9.

3.
J Hazard Mater ; 466: 133594, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38290334

RESUMO

Oil fouling is the crucial issue for the separation of oil-in-water emulsion by membrane technology. The latest research found that the membrane fouling rate was opposite to the widely used theoretical prediction by Derjaguin-Landau-Verwey-Overbeek (DLVO) or extended DLVO (XDLVO) theory. To interpret the contradiction, the molecular dynamics was adopted to explore the molecular behavior of oil and emulsifier (Tween 80) at membrane interface with the assistance of DLVO/XDLVO theory and membrane fouling models. The decreased flux attenuation and fitting of fouling models proved that the existence of Tween 80 effectively alleviated membrane fouling. Conversely, DLVO/XDLVO theory predicted that the membrane fouling should be exacerbated with the increase of Tween 80 concentration in O/W emulsion. This contradiction originated from the different interaction energy between oil/Tween 80 molecules and polyether sulfone (PES) membrane. The favorable free energy of Tween 80 was resulted from the sulfuryl groups in PES and hydrogen bonds (O-H…O) formation further strengthened the interaction. Therefore, Tween 80 could preferentially adsorb on membrane surface and form an isolation layer by demulsification and steric hindrance and resist the aggregation of oil, which effectively alleviated membrane fouling. This study provided a new insight in the interpretation of interaction in O/W emulsion.

4.
Int Wound J ; 21(1): e14366, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37705319

RESUMO

Wound infections and delayed complications after caesarean section surgical procedure to mothers would have a prevalence of discomfort, stress and dissatisfaction in the postpartum period. In this report, one-pot synthesis is used for the preparation of chitosan (CS)-based copper nanoparticles (nCu), which was used for the preparation of zinc oxide (ZnO) hydrogel as wound dressing materials after surgery. The antibacterial activity of (CS-nCu/ZnO) developed hydrogels was studied zone of inhibition, against gram-positive and gram-negative bacteria. The antibacterial activity of the CS-nCu/ZnO hydrogel demonstrated that nanoformulated hydrogel materials have provided excellent bactericidal action against clinically approved bacterial pathogens. The biocompatibility and in vitro wound healing potential of the developed wound closure materials were studied by MTT assay and wound scratch assay methods, respectively. The MTT assay and cell migration assay results demonstrated that CS-nCu/ZnO hydrogel material induces cell compatibility and effective cell proliferation ability. These findings suggest that the CS-nCu/ZnO hydrogel outperforms CS-ZnO in terms of wound healing and could be used as a wound closure material in caesarean section wound treatment.


Assuntos
Quitosana , Óxido de Zinco , Gravidez , Humanos , Feminino , Óxido de Zinco/uso terapêutico , Óxido de Zinco/farmacologia , Quitosana/uso terapêutico , Antibacterianos/farmacologia , Cobre/uso terapêutico , Cobre/farmacologia , Hidrogéis/uso terapêutico , Cesárea , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Cicatrização , Bandagens
5.
Chemosphere ; 340: 139911, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37611752

RESUMO

With the rapid increase of sludge production from sewage treatment plants, the treatment of sludge drying condensate rich in a large amount of pollutants urgently needs to be addressed. Due to the unique characteristics of sludge drying condensate (high ammonia nitrogen and COD concentration), there are almost no reports on biological treatment methods specifically targeting sludge drying condensate. In this study, A/O-MBR process was proposed for sludge drying condensate treatment and the effects of ammonia nitrogen loads, alkalinity and aeration intensity were explored. Experimental results show that under the ammonia nitrogen load of 0.35 kg NH4+-N/(m3·d) and the aeration intensity of 0.5 m3/(m2·min), the removal rate of COD and NH4+-N could reach 94% and 99.86% with the addition of alkalinity (m(NaHCO3): m(NH4+-N) = 7:1), respectively. The distribution of living and dead microbial cells in the activated sludge of three reactors also proved that the supplement of alkalinity in the influent can ensure the feasible living conditions for microorganisms. In addition to traditional nitrifying bacteria, through the supplementation of alkalinity and the reduction of aeration intensity, the system had also domesticated high abundance heterogeneous nitrification aerobic denitrification (HN-AD) and aerobic denitrification bacteria (both more than 10% of the total bacterial count). The denitrification process of sludge drying condensate was simplified and the denitrification efficiency was greatly improved. The findings of this study could provide important theoretical guidance for the biological treatment process of sludge drying condensate.


Assuntos
Poluentes Ambientais , Esgotos , Amônia , Dessecação , Suplementos Nutricionais
6.
Environ Pollut ; 335: 122145, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37422084

RESUMO

In this study, the removal efficiency and mechanism of 8 kinds of typical micropollutants by membrane bioreactor (MBR) at different temperatures (i.e. 15, 25 and 35 °C) were investigated. MBR exhibited the high removal rate (>85%) for 3 kinds of industrial synthetic organic micropollutants (i.e. bisphenol A (BPA), 4-tert-octylphenol (TB) and 4-n-nonylphenol (NP)) with similar functional groups, structures and high hydrophobicity (Log D > 3.2). However, the removal rates of ibuprofen (IBU), carbamazepine (CBZ) and sulfamethoxazole (SMX) with pharmaceutical activity showed great discrepancy (i.e. 93%, 14.2% and 29%, respectively), while that of pesticides (i.e. acetochlor (Ac) and 2,4-dichlorophenoxy acetic acid (2,4-D) were both lower than 10%. The results showed that the operating temperature played a significant role in microbial growth and activities. High temperature (35 °C) led to a decreased removal efficiency for most of hydrophobic organic micropollutants, and was also not conducive for refractory CBZ due to the temperature sensitivity. At lower temperature (15 °C), a large amount of exopolysaccharides and proteins were released by microorganisms, which caused the inhibited microbial activity, poor flocculation and sedimentation, resulting in the polysaccharide-type membrane fouling. It was proved that dominant microbial degradation of 61.01%-92.73% and auxiliary adsorption of 5.29%-28.30% were the main mechanisms for micropollutant removal in MBR system except for pesticides due to the toxicity. Therefore, the removal rates of most micropollutants were highest at 25 °C due to the high activity sludge so as to enhance microbial adsorption and degradation.


Assuntos
Praguicidas , Poluentes Químicos da Água , Temperatura , Poluentes Químicos da Água/análise , Compostos Orgânicos , Esgotos/química , Reatores Biológicos , Preparações Farmacêuticas , Membranas Artificiais , Eliminação de Resíduos Líquidos/métodos
7.
Elife ; 122023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36942939

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) continues to show no improvement in survival rates. One aspect of PDAC is elevated ATP levels, pointing to the purinergic axis as a potential attractive therapeutic target. Mediated in part by highly druggable extracellular proteins, this axis plays essential roles in fibrosis, inflammation response, and immune function. Analyzing the main members of the PDAC extracellular purinome using publicly available databases discerned which members may impact patient survival. P2RY2 presents as the purinergic gene with the strongest association with hypoxia, the highest cancer cell-specific expression, and the strongest impact on overall survival. Invasion assays using a 3D spheroid model revealed P2Y2 to be critical in facilitating invasion driven by extracellular ATP. Using genetic modification and pharmacological strategies, we demonstrate mechanistically that this ATP-driven invasion requires direct protein-protein interactions between P2Y2 and αV integrins. DNA-PAINT super-resolution fluorescence microscopy reveals that P2Y2 regulates the amount and distribution of integrin αV in the plasma membrane. Moreover, receptor-integrin interactions were required for effective downstream signaling, leading to cancer cell invasion. This work elucidates a novel GPCR-integrin interaction in cancer invasion, highlighting its potential for therapeutic targeting.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Linhagem Celular Tumoral , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Invasividade Neoplásica/genética , Trifosfato de Adenosina/metabolismo , Integrinas/metabolismo , Proliferação de Células/genética , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Receptores Purinérgicos P2Y2/genética , Receptores Purinérgicos P2Y2/metabolismo
8.
Eur J Med Res ; 28(1): 120, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36915204

RESUMO

BACKGROUND: Studies suggest that high-flow nasal cannula (HFNC) and non-invasive ventilation (NIV) can prevent reintubation in critically ill patients with a low risk of extubation failure. However, the safety and effectiveness in patients at high risk of extubation failure are still debated. Therefore, we conducted a systematic review and meta-analysis to compare the efficacies of HFNC and NIV in high-risk patients. METHODS: We searched eight databases (MEDLINE, Cochrane Library, EMBASE, CINAHL Complete, Web of Science, China National Knowledge Infrastructure, Wan-Fang Database, and Chinese Biological Medical Database) with reintubation as a primary outcome measure. The secondary outcomes included mortality, intensive care unit (ICU) length of stay (LOS), incidence of adverse events, and respiratory function indices. Statistical data analysis was performed using RevMan software. RESULTS: Thirteen randomized clinical trials (RCTs) with 1457 patients were included. The HFNC and NIV groups showed no differences in reintubation (RR 1.10, 95% CI 0.87-1.40, I2 = 0%, P = 0.42), mortality (RR 1.09, 95% CI 0.82-1.46, I2 = 0%, P = 0.54), and respiratory function indices (partial pressure of carbon dioxide [PaCO2]: MD - 1.31, 95% CI - 2.76-0.13, I2 = 81%, P = 0.07; oxygenation index [P/F]: MD - 2.18, 95% CI - 8.49-4.13, I2 = 57%, P = 0.50; respiratory rate [Rr]: MD - 0.50, 95% CI - 1.88-0.88, I2 = 80%, P = 0.47). However, HFNC reduced adverse events (abdominal distension: RR 0.09, 95% CI 0.04-0.24, I2 = 0%, P < 0.01; aspiration: RR 0.30, 95% CI 0.09-1.07, I2 = 0%, P = 0.06; facial injury: RR 0.27, 95% CI 0.09-0.88, I2 = 0%, P = 0.03; delirium: RR 0.30, 95%CI 0.07-1.39, I2 = 0%, P = 0.12; pulmonary complications: RR 0.67, 95% CI 0.46-0.99, I2 = 0%, P = 0.05; intolerance: RR 0.22, 95% CI 0.08-0.57, I2 = 0%, P < 0.01) and may have shortened LOS (MD - 1.03, 95% CI - 1.86-- 0.20, I2 = 93%, P = 0.02). Subgroup analysis by language, extubation method, NIV parameter settings, and HFNC flow rate revealed higher heterogeneity in LOS, PaCO2, and Rr. CONCLUSIONS: In adult patients at a high risk of extubation failure, HFNC reduced the incidence of adverse events but did not affect reintubation and mortality. Consequently, whether or not HFNC can reduce LOS and improve respiratory function remains inconclusive.


Assuntos
Cânula , Ventilação não Invasiva , Adulto , Humanos , Ventilação não Invasiva/efeitos adversos , Ventilação não Invasiva/métodos , Extubação , Unidades de Terapia Intensiva , Intubação Intratraqueal/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Oncogene ; 42(7): 491-500, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36357571

RESUMO

Pancreatic stellate cells (PSCs) are key to the treatment-refractory desmoplastic phenotype of pancreatic ductal adenocarcinoma (PDAC) and have received considerable attention as a stromal target for cancer therapy. This approach demands detailed understanding of their pro- and anti-tumourigenic effects. Interrogating PSC-cancer cell interactions in 3D models, we identified nuclear FGFR1 as critical for PSC-led invasion of cancer cells. ChIP-seq analysis of FGFR1 in PSCs revealed a number of FGFR1 interaction sites within the genome, notably NRG1, which encodes the ERBB ligand Neuregulin. We show that nuclear FGFR1 regulates transcription of NRG1, which in turn acts in autocrine fashion through an ERBB2/4 heterodimer to promote invasion. In support of this, recombinant NRG1 in 3D model systems rescued the loss of invasion incurred by FGFR inhibition. In vivo we demonstrate that, while FGFR inhibition does not affect the growth of pancreatic tumours in mice, local invasion into the pancreas is reduced. Thus, FGFR and NRG1 may present new stromal targets for PDAC therapy.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Camundongos , Animais , Regulação para Cima , Neuregulina-1/genética , Neuregulina-1/farmacologia , Células Estreladas do Pâncreas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética
11.
J Hazard Mater ; 436: 129224, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35739744

RESUMO

Peroxydisulfate (PDS)-based advanced oxidation processes (AOPs) have been demonstrated to be an effective technology for the removal of refractory organic contaminants from the aquatic environment. Herein, a photothermal synergistic strategy is developed to realize the green activation of PDS under solar light irradiation. An innovative solar photothermal reaction system and its corresponding evaluation method are established. The results show that there is a synergistic effect between light and light-generated thermal effects on the activation of PDS for effectively removing fulvic acid (FA). The maximum degradation percentage of FA increases from 42.6% to 90.8% after introducing ZrC nanoparticles as photothermal materials. The maximum temperature of the whole system is up to 66.4 â„ƒ after 120 min irradiation at 0.007 wt% solid content of ZrC, which is higher by 26.9% compared with that in the absence of ZrC nanoparticles. Furthermore, the underlying mechanism and PDS activation efficiency are deeply investigated. This work provides a viable strategy for directly using solar radiation to activate PDS for degrading refractory organic compounds, which creates a new avenue toward the utilization of solar energy for wastewater treatment.


Assuntos
Águas Residuárias , Purificação da Água , Compostos Orgânicos , Oxirredução , Purificação da Água/métodos
12.
J Hazard Mater ; 424(Pt B): 127362, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34638075

RESUMO

Development of economic and efficient absorbent for the simultaneous removal of antibiotics and heavy metals is needed. In this study, a three-dimensional porous ultrathin g-C3N4 (UCN) /graphene oxide (GO) hydrogel (UCN-GH) was prepared by co-assembling of UCN and GO nanosheets via the facile hydrothermal reaction. Characterizations indicated that the addition of UCN significantly decreased the reduction of CO and O-CO related groups of GO during the hydrothermal reaction and introduced amine groups on UCN-GH. The UCN-GH exhibited excellent ability on the co-removal of Cu(II) (qmax = 2.0-2.5 mmol g-1) and tetracycline (TC) (qmax = 1.2-3.0 mmol g-1) from water. The adsorption capacities were increased as UCN mass ratio increasing. The mutual effects between Cu(II) and TC were examined through adsorption kinetics and isotherm models. Characterizations and computational chemistry analysis indicated that Cu(II) is apt to coordinate with the amine groups on UCN than with oxygen groups on GO, which accounts for the enhanced adsorption ability of UCN-GH. In the binary system, Cu(II) acts as a bridge between TC and UCN-GH enhanced the removal of TC. The effects of pH and regular salt ions on the removal of Cu(II)/TC were examined. Moreover, the prepared UCN-GH also showed comparable co-adsorption capacities in practical water/wastewater.


Assuntos
Grafite , Poluentes Químicos da Água , Adsorção , Antibacterianos , Cobre , Hidrogéis , Cinética , Tetraciclina , Poluentes Químicos da Água/análise
13.
Chemosphere ; 287(Pt 1): 131968, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34438214

RESUMO

The effective interception of membrane leads to the accumulation of microplastics (MPs) in membrane bioreactor (MBR) process for long-term operation. However, the influence of MPs accumulation on the performance of MBR hasn't been well understood. In this study, the accumulation of polypropylene microplastics (PP-MPs) in two MBRs run for 3 yr with or without discharging sludge was simulated by operating the lab-scale MBRs for 84 days. The variations of pollutant removal, membrane fouling, composition of soluble microbial product (SMP) and extracellular polymeric substance (EPS), and microbial community of MBRs were systematically investigated. The results show that the removal efficiency of COD and NH4+-N was not depressed by PP-MPs accumulation. However, the presence of PP-MPs in the range of 0.14-0.30 g/L could inhibit the growth of microorganisms, enhance the secretion of SMP and EPS, and reduce the microbial richness and diversity. In the contrary, the high concentration of PP-MPs (2.34-5.00 g/L) exhibited the opposite effects and mitigated membrane fouling, suggesting the important role of MPs concentration. It was also found that the exposure to high concentration of PP-MPs enhanced relative abundance of Clostridia, and inhibited the growth of Proteobacteria. The findings of this study provide a foresight to understand the effects of MPs accumulation on the performance of MBRs.


Assuntos
Microplásticos , Purificação da Água , Reatores Biológicos , Matriz Extracelular de Substâncias Poliméricas , Membranas Artificiais , Plásticos , Esgotos
14.
Bioresour Technol ; 340: 125728, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34385130

RESUMO

This study proposes a novel strategy to obtain high-efficiency synchronous removal of nitrogen and phosphorus from wastewater by the limited-aeration anaerobic/anoxic/aerobic membrane bioreactor (AAO-MBR) and evaluates its resource recovery potential. Effects of membrane flux on pollutants removal and membrane fouling were investigated, and the optimal flux of 30 L/(m2·h) was obtained with efficient nitrogen and phosphorus removal of 81.5 ± 6.1% and 96.7 ± 2.1%. Compared with traditional and chemical-aided AAO-MBRs, limited-aeration AAO-MBR also alleviated membrane fouling by enlarging sludge flocs, improved sludge activities, and enriched the functional bacteria and genes. The sludge denitrification activity and phosphorus uptake activity of the limited-aeration AAO-MBR were 1.7 and 4.2 times as those of the traditional AAO-MBR. Low-temperature sludge pyrolysis results showed that sludge from limited-aeration AAO-MBR had higher nutrient storage and release capacity. This study proved the efficient nutrient removal capacity and high resource recovery potential of the limited-aeration AAO-MBR process.


Assuntos
Reatores Biológicos , Eliminação de Resíduos Líquidos , Anaerobiose , Nutrientes , Esgotos
15.
Bioresour Technol ; 338: 125527, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34274586

RESUMO

An electrochemical membrane-aerated biofilm reactor (EMABR) was developed for removing sulfamethoxazole (SMX) and trimethoprim (TMP) from contaminated water. The exertion of electric field greatly enhanced the degradation of SMX and TMP in the EMABR (~60%) compared to membrane-aerated biofilm reactor (MABR, < 10%), due to the synergistic effects of the electro-oxidation (the generation of reactive oxygen species) and biological degradation. Microbial community analyses demonstrated that the EMABR enriched the genus of Xanthobacter, which was potentially capable of degrading aromatic intermediates. Moreover, the EMABR had a lower relative abundance of antibiotic resistance genes (ARGs) (0.23) compared to the MABR (0.56), suggesting the suppression of ARGs in the EMABR. Further, the SMX and TMP degradation pathways were proposed based on the detection of key intermediate products. This study demonstrated the potential of EMABR as an effective technology for removing antibiotics from micro-polluted surface water and suppressing the development of ARGs.


Assuntos
Antibacterianos , Águas Residuárias , Antibacterianos/farmacologia , Biofilmes , Reatores Biológicos , Resistência Microbiana a Medicamentos/genética , Sulfametoxazol , Água
16.
Cells ; 10(4)2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33918004

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis with a 5 year survival rate of less than 8%, and is predicted to become the second leading cause of cancer-related death by 2030. Alongside late detection, which impacts upon surgical treatment, PDAC tumours are challenging to treat due to their desmoplastic stroma and hypovascular nature, which limits the effectiveness of chemotherapy and radiotherapy. Pancreatic stellate cells (PSCs), which form a key part of this stroma, become activated in response to tumour development, entering into cross-talk with cancer cells to induce tumour cell proliferation and invasion, leading to metastatic spread. We and others have shown that Fibroblast Growth Factor Receptor (FGFR) signalling can play a critical role in the interactions between PDAC cells and the tumour microenvironment, but it is clear that the FGFR signalling pathway is not acting in isolation. Here we describe our current understanding of the mechanisms by which FGFR signalling contributes to PDAC progression, focusing on its interaction with other pathways in signalling networks and discussing the therapeutic approaches that are being developed to try and improve prognosis for this terrible disease.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Transdução de Sinais , Humanos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células Estreladas do Pâncreas/metabolismo , Células Estreladas do Pâncreas/patologia , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo
17.
Regen Biomater ; 8(3): rbab015, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35707698

RESUMO

We have designed and developed an effective drug delivery system using biocompatible polymer of poly (ethylene glycol)-polyaspartic acid (mPEG-PAsp) for co-loading the chemotherapy drugs paclitaxel (PTX) and cisplatin (CP) in one nano-vehicle. This study aimed to improve the anti-cancer efficacy of combinations of chemotherapy drugs and reduce their side effects. mPEG-PAsp-(PTX/Pt) nano-micelles disperse well in aqueous solution and have a narrow size distribution (37.8 ± 3.2 nm) in dynamic light scattering (DLS). Drug release profiles found that CP released at pH 5.5 was significantly faster than that at pH 7.4. MPEG-PAsp-(PTX/Pt) nano-micelles displayed a significantly higher tumor inhibitory effect than mPEG-PAsp-PTX nano-micelles when the polymer concentrations reached 50 µg/mL. Our data indicated that polymer micelles of mPEG-PAsp loaded with the combined drug exert synergistic anti-tumor efficacy on SKOV3 ovarian cells via different action mechanisms. Results from our studies suggested that mPEG-PAsp-(PTX/Pt) nano-micelles are promising alternatives for carrying and improving the delivery of therapeutic drugs with different water solubilities.

18.
Water Environ Res ; 93(3): 360-369, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32725934

RESUMO

In this study, the different graphene derivatives, graphene oxide (GO), carboxylic acid-modified graphene (G-COOH), and amine-modified graphene (G-NH2 ), were used to prepare polyvinylidene fluoride (PVDF) composite membranes. The membrane modification performance was evaluated using the extended Derjaguin-Landau-Verwey-Overbeek theory and quartz crystal microbalance dissipation monitoring. The results show that the addition of low-dose GO and G-NH2 can improve membrane surface porosity and permeability. The hydrophilicity and electron donor monopolarity of PVDF/GO composite membranes were enhanced by adding more than 0.024 wt% GO, thus improving its antifouling ability. In addition, the enhancement of hydrophilicity, free energy of cohesion, and antifouling ability of composite membrane modified with G-COOH and G-NH2 was more significant compared with that of GO with the same dosage, which implies the important role of functional group in additives. This study provides new insights for the blending modification of PVDF membranes by systematically comparing the addition of graphene derivatives with different functional groups. PRACTITIONER POINTS: The comprehensive comparison of membrane modification with different graphene derivatives was investigated. The enhancement of hydrophilicity and antifouling ability of membranes modified with G-COOH and G-NH2 was more significant than that of GO. The free energy of cohesion of nanocomposite membrane was affected by the functional group of additives. G-NH2 composite membrane had the best comprehensive performance with great hydrophilicity, permeability, and antifouling performance.


Assuntos
Incrustação Biológica , Grafite , Membranas Artificiais , Polivinil , Técnicas de Microbalança de Cristal de Quartzo
19.
Sci Total Environ ; 728: 138557, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32361109

RESUMO

The purpose of this study is to investigate the effect of COD/N interference on mature anammox granular sludge formed by different biological carriers. Three anammox granular sludge rectors were established with no biological carriers (R1), GAC (R2) and PVA-gel bead (R3), respectively. As the COD/N ratio increased to 1:2, the activity of anaerobic ammonia oxidizing bacteria in R1 and R2 was significantly inhibited. However, the nitrogen removal effect of R3 did not decrease dramatically, and the nitrogen removal rate in this phase was 1.54 ± 0.05 kg N/m3·d. As the COD/N ratio increased to 1:1.5, the removal of NH4+-N in all reactors gradually decreased. The order of COD resistance of the three reactors in this study was R3 > R2 > R1. It was found that Candidatus Brocadia might be sensitive to the presence of organic matter. The abundance of heterotrophic denitrifying bacteria increased gradually in each reactor under increased influent COD/N ratios.


Assuntos
Reatores Biológicos , Esgotos , Amônia , Anaerobiose , Bactérias , Desnitrificação , Nitrogênio , Oxirredução
20.
Mini Rev Med Chem ; 20(2): 123-133, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31648635

RESUMO

Natural compounds, such as paclitaxel and camptothecin, have great effects on the treatment of tumors. Such natural chemicals often achieve anti-tumor effects through a variety of mechanisms. Therefore, it is of great significance to conduct further studies on the anticancer mechanism of natural anticancer agents to lay a solid foundation for the development of new drugs. Myricetin, originally isolated from Myrica nagi, is a natural pigment of flavonoids that can inhibit the growth of cancer cells (such as liver cancer, rectal cancer, skin cancer and lung cancer, etc.). It can regulate many intracellular activities (such as anti-inflammatory and blood lipids regulation) and can even be bacteriostatic. The purpose of this paper is to outline the molecular pathways of the anticancer effects of myricetin, including the effect on cancer cell death, proliferation, angiogenesis, metastasis and cell signaling pathway.


Assuntos
Antineoplásicos/farmacologia , Flavonoides/farmacologia , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Flavonoides/química , Humanos , Estrutura Molecular , Neoplasias/patologia , Transdução de Sinais/efeitos dos fármacos
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