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1.
Environ Sci Technol ; 58(37): 16632-16641, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39216011

RESUMO

Conductive nanofiltration (CNF) membranes hold great promise for removing small organic pollutants from water through enhanced Donnan exclusion and electrocatalytic degradation. However, current CNF membranes face limitations in conductivity, structural stability, and nanochannel control strategies. This work addresses these challenges by introducing aniline-functionalized carbon nanotubes (NH2-CNTs) as an interlayer. NH2-CNTs enhance the dispersibility and adhesion of pristine carbon nanotubes, leading to a more conductive and stable composite nanofiltration membrane. The redesigned NH2-CNTs interlayered conductive nanofiltration (NICNF) membrane exhibits a 10-fold increase in conductivity and a high response degree (80%) with excellent cyclic stability, surpassing existing CNF membranes. The synergistic effects of enhanced Donnan exclusion, voltage switching, and electrocatalysis enable the NICNF membrane to achieve selective recovery of mixed dyes, 98.97% removal of residual wastewater toxicity, and a 5.2-fold increase in permeance compared to the commercial NF270 membrane. This research paves the way for next-generation multifunctional membranes capable of the efficient recovery and degradation of toxic organic pollutants in wastewater.


Assuntos
Filtração , Membranas Artificiais , Nanotubos de Carbono , Poluentes Químicos da Água , Nanotubos de Carbono/química , Poluentes Químicos da Água/química , Compostos de Anilina/química , Águas Residuárias/química , Purificação da Água/métodos , Condutividade Elétrica
2.
Blood Purif ; 53(6): 486-492, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38198755

RESUMO

INTRODUCTION: The objective of this study was to report our experience of angioplasty with paclitaxel-coated balloon (PCB) versus common balloon (CB) for the treatment of repeated failing vascular access. METHODS: Retrospective, single-center analysis consisting of 88 patients treated with percutaneous transluminal angioplasty in the period from October 2020 through December 2021. Patients were divided into two groups according to the type of treatment as PCB (n = 41) and CB (n = 47). We analyzed target lesion primary patency and vascular access primary patency for 6 months and the rate of complications. RESULTS: There was no significant difference in the target lesion primary patency which was similar for 6 months between the two groups (PCB group vs. CB group at 1, 3, and 6 months; 95.12 vs. 89.36% (p = 0.55), 75.61 versus 74.47% (p = 0.90), 53.66% versus 63.83% (p = 0.33), respectively). Similarly, vascular access primary patency in the PCB group and CB group was 90.24 and 89.36% (p = 0.83), respectively, at 1 month, 65.85 and 68.09% (p = 0.82), respectively, at 3 months, 39.02 and 53.19% (p = 0.18), respectively, at 6 months. There were no major complications after endovascular treatment. CONCLUSION: Compared to CB angioplasty, PCB angioplasty has no short-term patency benefit in the treatment of vascular access repeated stenosis.


Assuntos
Angioplastia com Balão , Paclitaxel , Diálise Renal , Grau de Desobstrução Vascular , Humanos , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Estudos Retrospectivos , Masculino , Feminino , Angioplastia com Balão/métodos , Pessoa de Meia-Idade , Idoso , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/terapia , Dispositivos de Acesso Vascular , Materiais Revestidos Biocompatíveis , Constrição Patológica
3.
Surg Endosc ; 37(10): 7649-7657, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37491656

RESUMO

INTRODUCTION: Although transoral endoscopic thyroidectomy (TOETVA) is widely utilized in clinical practice, some problems and restrictions still remain. Our study compared the perioperative features and early surgical efficacy of TOETVA and a modified transoral and submental endoscopic thyroidectomy (TOaST) in early stage papillary thyroid carcinoma (PTC). METHODS: The clinical data of PTC patients who underwent endoscopic thyroidectomy, including 42 modified TOaST patients and 114 traditional TOETVA patients, were retrospectively collected. Propensity score matching was employed to reduce patient selection bias. The perioperative features and early surgical efficacy data of two groups were compared. RESULTS: The operation time of the TOaST group was significantly shorter than that of the TOETVA group (150.00 ± 35.47 min vs. 168.75 ± 44.49 min; P = 0.030). Furthermore, the TOaST group required shorter days for a normal diet (3.38 ± 0.93 days vs. 4.04 ± 1.03 days; P = 0.000) and a shorter hospital stay than the TOETVA group (5.85 ± 2.17 days vs. 6.12 ± 2.01 days; P = 0.003). There was no statistical difference in complications between the two groups, but the probability of numbness of the lower lip and chin in the TOaST group was lower than that in the TOETVA group(5.12% vs. 13.04%, P = 0.321). The symptoms of mandibular numbness and hoarseness of most patients were relieved in both groups 6 months after surgery, and no abnormalities and recurrence were found in the thyroid ultrasound. All the patients were satisfied with the appearance of their surgical incision. CONCLUSION: In early stage PTC patients, TOaST had the same surgical effectiveness as traditional TOETVA but can minimize the probability of mandibular numbness and improve the perioperative quality of life.


Assuntos
Cirurgia Endoscópica por Orifício Natural , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/cirurgia , Câncer Papilífero da Tireoide/patologia , Tireoidectomia , Estudos Retrospectivos , Hipestesia/cirurgia , Qualidade de Vida , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia
4.
Mol Biol Evol ; 34(1): 88-92, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27744409

RESUMO

Molecular basis for mammalian echolocation has been receiving much concerns. Recent findings on the parallel evolution of prestin sequences among echolocating bats and toothed whales suggest that adaptations for high-frequency hearing have occurred during the evolution of echolocation. Here, we report that although the species tree for echolocating bats emitting echolocation calls with frequency modulated (FM) sweeps is paraphyletic, prestin exhibits similar functional changes between FM bats. Site-directed mutagenesis shows that the amino acid 308S in FM bats is responsible for the similar functional changes of prestin We strongly support that the occurrence of serine at position 308 is a case of hemiplasy, caused by incomplete lineage sorting of an ancestral polymorphism. Our study not only reveals sophisticated molecular basis of echolocation in bats, but also calls for caution in the inference of molecular convergence in species experiencing rapid radiation.


Assuntos
Proteínas de Transporte de Ânions/genética , Quirópteros/fisiologia , Ecolocação/fisiologia , Evolução Molecular , Animais , Evolução Biológica , Quirópteros/genética , Bases de Dados de Ácidos Nucleicos , Mutagênese Sítio-Dirigida , Filogenia , Polimorfismo Genético , Seleção Genética
5.
Mol Biol Evol ; 31(9): 2415-24, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24951728

RESUMO

Echolocation is a sensory system whereby certain mammals navigate and forage using sound waves, usually in environments where visibility is limited. Curiously, echolocation has evolved independently in bats and whales, which occupy entirely different environments. Based on this phenotypic convergence, recent studies identified several echolocation-related genes with parallel sites at the protein sequence level among different echolocating mammals, and among these, prestin seems the most promising. Although previous studies analyzed the evolutionary mechanism of prestin, the functional roles of the parallel sites in the evolution of mammalian echolocation are not clear. By functional assays, we show that a key parameter of prestin function, 1/α, is increased in all echolocating mammals and that the N7T parallel substitution accounted for this functional convergence. Moreover, another parameter, V1/2, was shifted toward the depolarization direction in a toothed whale, the bottlenose dolphin (Tursiops truncatus) and a constant-frequency (CF) bat, the Stoliczka's trident bat (Aselliscus stoliczkanus). The parallel site of I384T between toothed whales and CF bats was responsible for this functional convergence. Furthermore, the two parameters (1/α and V1/2) were correlated with mammalian high-frequency hearing, suggesting that the convergent changes of the prestin function in echolocating mammals may play important roles in mammalian echolocation. To our knowledge, these findings present the functional patterns of echolocation-related genes in echolocating mammals for the first time and rigorously demonstrate adaptive parallel evolution at the protein sequence level, paving the way to insights into the molecular mechanism underlying mammalian echolocation.


Assuntos
Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Ecolocação , Audição , Mamíferos/genética , Adaptação Biológica , Animais , Evolução Molecular , Células HEK293 , Humanos , Mamíferos/classificação , Mamíferos/fisiologia , Filogenia
6.
Arch Orthop Trauma Surg ; 135(7): 943-51, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26009255

RESUMO

INTRODUCTION: Titanium-nickel shape memory alloy (Ti-Ni SMA) is characterized by shape-memory effect, super-elasticity, excellent fatigue behavior, corrosion resistance, acceptable biocompatibility and high damping capacity. MATERIALS AND METHODS: Claw-like Ti-Ni SMA fixator (SMA-claw) has been used to treat transverse fracture of patella. 29 patients (19 males, 10 females) aged from 21 to 71 years old (averaged 43.0 years old) have been received open reduction and internal fixation with SMA-claw from January 2011 to December 2011. After operation, patients have been received gradual knee function exercises, followed by radiographic analysis and Lysholm Knee Score at 1, 2, 3, 6, 9 and 12 months postoperation. RESULTS: The mean follow-up time was 11.48 months (25 patients finished, 1 lost after 6 months and 3 lost after 9 months). Radiographic bone union occurred at 2 months (7 patients) or 3 months (22 patients). Satisfied range of motion for the knee joint has been observed with 1.90/141.72° (hyperextension/flexion) at 3 months, 4.83/143.97° at 6 months, 4.82/144.82° at 9 months and 5.2/145° at 12 months postsurgery. CONCLUSION: The Ti-Ni SMA-claw fixator produced good osteosynthesis effect by continuous recovery stress with relatively simple and minimally invasive handling process, which can be introduced as an alternative to traditional tension band technique for treatment of patellar transverse fracture.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/instrumentação , Fraturas Ósseas/cirurgia , Patela/lesões , Adulto , Idoso , Ligas , Desenho de Equipamento , Feminino , Fixação Interna de Fraturas/métodos , Consolidação da Fratura , Fraturas Ósseas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Níquel , Patela/diagnóstico por imagem , Patela/cirurgia , Estudos Prospectivos , Radiografia , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Titânio , Resultado do Tratamento , Adulto Jovem
7.
Small ; 10(23): 4886-94, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25059988

RESUMO

Light-responsive hydrogel particles with multi-compartmental structure are useful for applications in microreactors, drug delivery and tissue engineering because of their remotely-triggerable releasing ability and combinational functionalities. The current methods of synthesizing multi-compartmental hydrogel particles typically involve multi-step interrupted gelation of polysaccharides or complicated microfluidic procedures with limited throughput. In this study, a two-step sequential gelation process is developed to produce agarose/alginate double network multi-compartmental hydrogel particles using droplets assemblies induced by superhydrophobic surface as templates. The agarose/alginate double network multi-compartmental hydrogel particles can be formed with diverse hierarchical structures showing combinational functionalities. The synthesized hydrogel particles, when loaded with polypyrrole (PPy) nanoparticles that act as photothermal nanotransducers, are demonstrated to function as near-infrared (NIR) light triggerable and deformation-free hydrogel materials. Periodic NIR laser switching is applied to stimulate these hydrogel particles, and pulsatile release profiles are collected. Compared with massive reagents released from single-compartmental hydrogel particles, more regulated release profiles of the multi-compartmental hydrogel particles are observed.


Assuntos
Hidrogéis/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Alginatos/química , Cobre/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Géis/química , Interações Hidrofóbicas e Hidrofílicas , Raios Infravermelhos , Lasers , Luz , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanopartículas/química , Nanotubos/química , Polímeros/química , Pirróis/química , Sefarose/química , Engenharia Tecidual/métodos , Água/química
8.
Mar Pollut Bull ; 207: 116950, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39243470

RESUMO

Microplastic (MP) pollution has emerged as a global concern, prompting numerous studies on MP detection. Due to the remaining methodological challenges, it affects the accuracy and reliability of MP's impact assessment on river systems. To address this, the establishment of standardized operating protocols is crucial, encompassing sampling, separation, digestion, and characterization methods. This study evaluates the current tools used for identifying and quantifying MPs in riverine ecosystems, aiming to offer harmonized guidelines for future protocols. Recommendations include adopting a consistent format for reporting MP concentrations and providing improved information on sampling, separation, and digestion for enhanced cross-study comparisons. The importance of quality assurance and quality control is also discussed. Furthermore, we highlight unresolved issues, proposing avenues for further investigation. Suggestions encompass standardizing river sampling methods, optimizing technical steps and analysis processes, and enhancing the accuracy, reliability, and comparability of detection data to advance our understanding of MPs in river environments.


Assuntos
Monitoramento Ambiental , Microplásticos , Rios , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Rios/química , Microplásticos/análise , Poluentes Químicos da Água/análise , Ecossistema
9.
Mar Pollut Bull ; 205: 116656, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38950516

RESUMO

Microplastics (MPs) are the pollutants, found widely across various environmental media. However, studies on the MP pollution in urban rivers and the necessary risk assessments remain limited. In this study, the abundance and characteristics of microplastics in a typical urban river were examined to evaluate their distribution, sources, and ecological risks. It was observed that the abundance of MPs in sediments (220-2840 items·kg-1 dry weight (DW)) was much higher than that in surface water (2.9-10.3 items·L-1), indicating that the sediment is the "sink" of river MPs. Surface water and sediment were dominated by small particle size MPs (< 0.5 mm). Fiber and debris were common shapes of MPs in rivers and sediments. The microplastics in river water and sediments were primarily white and transparent, respectively. Polypropylene (PP) and polyethylene (PE) were the major polymers found.


Assuntos
Monitoramento Ambiental , Microplásticos , Rios , Poluentes Químicos da Água , Microplásticos/análise , Rios/química , China , Poluentes Químicos da Água/análise , Medição de Risco , Sedimentos Geológicos/química
10.
ACS Nano ; 18(28): 18211-18229, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38946122

RESUMO

Transarterial chemoembolization (TACE), the mainstay treatment of unresectable primary liver cancer that primarily employs nondegradable drug-loaded embolic agents to achieve synergistic vascular embolization and locoregional chemotherapy effects, suffers from an inferior drug burst behavior lacking long-term drug release controllability that severely limits the TACE efficacy. Here we developed gelatin-based drug-eluting microembolics grafted with nanosized poly(acrylic acid) serving as a biodegradable ion-exchange platform that leverages a counterion condensation effect to achieve high-efficiency electrostatic drug loading with electropositive drugs such as doxorubicin (i.e., drug loading capacity >34 mg/mL, encapsulation efficiency >98%, and loading time <10 min) and an enzymatic surface-erosion degradation pattern (∼2 months) to offer sustained locoregional pharmacokinetics with long-lasting deep-tumor retention capability for TACE treatment. The microembolics demonstrated facile microcatheter deliverability in a healthy porcine liver embolization model, superior tumor-killing capacity in a rabbit VX2 liver cancer embolization model, and stabilized extravascular drug penetration depth (>3 mm for 3 months) in a rabbit ear embolization model. Importantly, the microembolics finally exhibited vessel remodeling-induced permanent embolization with minimal inflammation responses after complete degradation. Such a biodegradable ion-exchange drug carrier provides an effective and versatile strategy for enhancing long-term therapeutic responses of various local chemotherapy treatments.


Assuntos
Quimioembolização Terapêutica , Doxorrubicina , Animais , Quimioembolização Terapêutica/métodos , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Coelhos , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/tratamento farmacológico , Suínos , Resinas Acrílicas/química , Polieletrólitos/química , Portadores de Fármacos/química , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/farmacocinética , Gelatina/química , Nanopartículas/química , Humanos , Liberação Controlada de Fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem
11.
Int J Biol Macromol ; 261(Pt 2): 129829, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38296134

RESUMO

Three-dimensional interpenetrating and hierarchically porous carbon material is an efficient catalyst support in water remediation and it is still a daunting challenge to establish the relationship between hierarchically porous structure and catalytic degradation performance. Herein, a highly porous silica (SiO2)/cellulose-based carbon aerogel with iron-based catalyst (FexOy) was fabricated by in-situ synthesis, freeze-drying and pyrolysis, where the addition of SiO2 induced the hierarchically porous morphology and three-dimensional interpenetrating sheet-like network with nitrogen doping. The destruction of cellulose crystalline structure by SiO2 and the iron-catalyzed breakdown of glycosidic bonds synergistically facilitated the formation of electron-rich graphite-like carbon skeleton. The unique microstructure is confirmed to be favorable for the diffusion of reactants and electron transport during catalytic process, thus boosting the catalytic degradation performance of carbon aerogels. As a result, the catalytic degradation efficiency of tetracycline under light irradiation by adding only 5 mg of FexOy/SiO2 cellulose carbon aerogels was as high as 90 % within 60 min, demonstrating the synergistic effect of photocatalysis and Fenton reaction. This ingenious structure design provides new insight into the relationship between hierarchically porous structure of carbon aerogels and their catalytic degradation performance, and opens a new avenue to develop cellulose-based carbon aerogel catalysts with efficient catalytic performance.


Assuntos
Carbono , Compostos Heterocíclicos , Carbono/química , Ferro/química , Dióxido de Silício , Celulose/química , Porosidade , Tetraciclina/química , Antibacterianos , Catálise
12.
Water Res ; 252: 121251, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38324983

RESUMO

Nanofiltration (NF) membranes play a pivotal role in water treatment; however, the persistent challenge of membrane fouling hampers their stable application. This study introduces a novel approach to address this issue through the creation of a poly(3,4-ethylenedioxythiophene) (PEDOT)-based conductive membrane, achieved by synergistically coupling interfacial polymerization (IP) with in situ self-polymerization of EDOT. During the IP reaction, the concurrent generation of HCl triggers the protonation of EDOT, activating its self-polymerization into PEDOT. This interwoven structure integrates with the polyamide network to establish a stable selective layer, yielding a remarkable 90 % increase in permeability to 20.4 L m-2 h-1 bar-1. Leveraging the conductivity conferred by PEDOT doping, an electro-assisted cleaning strategy is devised, rapidly restoring the flux to 98.3 % within 5 min, outperforming the 30-minute pure water cleaning approach. Through simulations in an 8040 spiral-wound module and the utilization of the permeated salt solution for cleaning, the electro-assisted cleaning strategy emerges as an eco-friendly solution, significantly reducing water consumption and incurring only a marginal electricity cost of 0.055 $ per day. This work presents an innovative avenue for constructing conductive membranes and introduces an efficient and cost-effective electro-assisted cleaning strategy to effectively combat membrane fouling.


Assuntos
Membranas Artificiais , Compostos Orgânicos , Polimerização , Permeabilidade , Condutividade Elétrica
13.
Environ Sci Technol ; 47(22): 13167-74, 2013 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-24117418

RESUMO

In this paper, we report the technical breakthroughs to synthesize outer-selective thin-film composite (TFC) hollow fiber membranes, which is in an urgent need for osmotic power generation with the pressure-retarded osmosis (PRO) process. In the first step, a defect-free thin-film composite membrane module is achieved by vacuum-assisted interfacial polymerization. The PRO performance is further enhanced by optimizing the support in terms of pore size and mechanical strength and the TFC layer with polydopamine coating and molecular engineering of the interfacial polymerization solution. The newly developed membranes can stand over 20 bar with a peak power density of 7.63 W/m(2), which is equivalent to 13.72 W/m(2) of its inner-selective hollow fiber counterpart with the same module size, packing density, and fiber dimensions. The study may provide insightful guidelines for optimizing the interfacial polymerization procedures and scaling up of the outer-selective TFC hollow fiber membrane modules for PRO power generation.


Assuntos
Fontes Geradoras de Energia , Membranas Artificiais , Pressão Osmótica , Polimerização , Pressão , Vácuo , Indóis/química , Peso Molecular , Permeabilidade , Polímeros/química , Porosidade
14.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 35(1): 108-11, 2013 Feb.
Artigo em Zh | MEDLINE | ID: mdl-23472858

RESUMO

OBJECTIVE: To investigate the feasibility of hip arthroplasty in the treatment of elderly patients with Evans I-III intertrochanteric fracture of femur by analyzing its biomechanics characters. METHODS: We solved the CT digital image files with the graphics processing software Mimics at DICOM 3.0 standard, and reconstructed the three-dimensional entity of femur with CAD modeling software Unigraphics. Then the fracture line was defined in the model as the line between the tip of greater trochanter and inferior margin of small trochanter, above which the upper bone was removed. Afterwards the two prosthesises with different stem lengths (120 mm and 170 mm) were implanted into the fracture model respectively as hip arthroplasty with 3 mm bone cement layer between prosthesis and femur, and the bone defect was repatched with 5 mm bone cement layer. A three-dimensional finite element model was established with finite element analysis software ABAQUS 6.5. We formulated different material parameters under the stress condition standing with single leg to build the stress distribution map of the femur prosthesis, and took 5 loci of region of stress concentration to calculate the mean value of stress. RESULTS: The stress distribution maps of the short and long stem length prothesises were similar. And there were two areas of stress concentration, including the upper portion and the lower portion close to the joint of the prosthesis stem, and the stress concentration in the junction part was obviously between the lower portion and the upper area of the small trachanter. The stress reached the first concentration area at the junction and then gradually reached the second concentration area at the interior terminal of the stem. While the stress gradually increased along the lateral prosthesis stem, and reached the stress concentration area at the end. CONCLUSIONS: The stress distribution maps in the femur prosthesises are similar between hip arthroplasty in the treatment of intertrochanteric fracture of femur and the traditional hip arthroplasty surgery. The peak stress values are higher in the long stem prosthesis in the treatment of intertrochanteric fracture of femur than the short type, while they are under the rupture value of the metal.


Assuntos
Artroplastia de Quadril/instrumentação , Fraturas do Quadril/cirurgia , Prótese de Quadril , Idoso , Artroplastia de Quadril/métodos , Fenômenos Biomecânicos , Cimentos Ósseos , Simulação por Computador , Feminino , Análise de Elementos Finitos , Humanos , Processamento de Imagem Assistida por Computador , Software , Estresse Mecânico
15.
Environ Sci Process Impacts ; 25(9): 1479-1490, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37581367

RESUMO

Rivers are important channels for the transport of microplastics (MPs) from land to sea. In this work, the temporal variation and risk assessment of MP pollution in the surface water of the Wei River, a typical seasonal river in northern China, were quantified. The number abundance of MPs in the dry season was significantly higher than that in the wet season (p < 0.05). Fiber was the most abundant type of MP in both dry and wet seasons. Infrared spectrometer and Raman spectroscopy identification showed that polypropylene (PP) and polyethylene (PE) were the major polymers found in both dry and wet seasons, and the mixture of different MP polymers was more diverse in the dry season. The risk assessment showed that the average pollution load index (PLI) and risk quotient (RQ) were 2.10 and 1.19 in the dry season, which significantly decreased to 1.25 and 0.74, respectively, in the wet season (p < 0.05). In total, the results from this study highlight the characteristics of seasonal rivers that influence the temporal distribution and risk assessment of microplastics, providing scientific reference for policymakers and river managers to effectively deal with MP pollution.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Estações do Ano , Rios/química , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Polímeros , China , Medição de Risco
16.
Huan Jing Ke Xue ; 44(1): 231-242, 2023 Jan 08.
Artigo em Zh | MEDLINE | ID: mdl-36635811

RESUMO

This study aimed to explore the occurrence state, morphological characteristics, polymer types, as well as potential ecology of microplastics in the Weihe River in Northwest China. Thus, we identified the abundance distribution, shape, particle size, color, and polymer type of microplastics in the surface water of the Weihe River by conducting field sampling, microscope observation, Fourier infrared spectroscopy, Micro-Raman spectroscopy, etc., during the normal water period (May) of 2021. Subsequently, we analyzed the potential ecological and environmental risks of microplastics using the pollution load index method and species sensitivity distribution method. The results showed that microplastics were detected to exist in all sampling points and the abundance ranged from (2.9±0.8) to (10.3±2.8) n·L-1. The concentration of microplastics in the main stream of the Weihe River was higher than that in the tributaries. Fiber (15.04%-77.03%), small size (<0.5 mm) (27.27%-89.38%), and colored (15.85%-49.53%) were the predominant microplastic types. Polyethylene (32.98%), polypropylene (29.79%), polystyrene (21.21%), and polyethylene (10.61%) terephthalate were the main types of polymers detected. In general, the microplastic pollution in Weihe River was at a medium level and had not affected aquatic organisms, but its high concentration and the characteristic of the plastics to adsorb other pollutants are still of concern.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Polietileno , China , Água
17.
Chemosphere ; 318: 137930, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36693478

RESUMO

The nanofiltration (NF) membranes with the specific separation accuracy for molecules with the size of 0.5-2 nm have been applied in various industries. However, the traditional polymeric NF membranes still face problems like the trade-off effect, organic solvent consumption, and weak durability in harsh conditions. The participation of coordination action or metal-organic coordination compounds (MOCs) brings the membrane with uniform pores, better antifouling properties, and high hydrophilicity. Some of the aqueous-phase reactions also help to introduce a green fabrication process to NF membranes. This review critically summarizes the recent research progress in coordination chemistry relevant NF membranes. The participation of coordination chemistry was classified by the various functions in NF membranes like additives, interlayers, selective layers, coating layers, and cross-linkers. Then, the effect and mechanism of the coordination chemistry on the performance of NF membranes are discussed in depth. Perspectives are given for the further promotion that coordination chemistry can make in NF processes. This review also provides comprehensive insight and constructive guidance on high-performance NF membranes with coordination chemistry.


Assuntos
Indústrias , Polímeros , Membranas
18.
J Colloid Interface Sci ; 630(Pt A): 772-782, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36283265

RESUMO

Immobilizing catalyst system faces the challenge of balancing catalysts stability and exposure of active site in water treatment. In this study, a novel in-situ synthesis of monoclinic phase of titanium dioxide (TiO2(B)) in cellulose-derived carbon aerogel (TCA) is proposed for processing multi-task in water treatment. The homogeneous gelation reaction supported the high dispersion of TiO2(B) in carbon skeleton. Meanwhile, TiO2 acts as crosslinker to reinforce cellulose network, then the grain refinement of amorphous TiO2 is limited to obtain TiO2(B) during carbonization. Benefiting from the reinforced structure, TCA remains the porous structure after carbonization and exposes more adsorption site than carbon aerogel blended with anatase particles (ACA). The adsorption performance of TCA are 837.3 mg/g, 1156.2 mg/g and 512.6 mg/g on methylene blue, malachite green and crystal violet, respectively. Compared with ACA, the superior interaction between TiO2 and graphite-like carbon improves the degradation rate of tetracycline from 1.3 × 10-3 min-1 to 8.6 × 10-3 min-1, and maintains the degradation efficiency in 3 rounds cyclic test. Besides, TCA also exhibits nearly twice to ACA on absorption capacity of different oil. This facile in-situ synthesis method offers a new insight in fabricating carbon aerogel immobilized photocatalysts system for multi-task in water treatment.


Assuntos
Nanocompostos , Purificação da Água , Carbono , Titânio/química , Nanocompostos/química , Celulose/química , Catálise
19.
Adv Healthc Mater ; 12(30): e2301645, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37557883

RESUMO

Developing efficient integrated diagnosis and treatment agents based on fuel-free self-movement nanomotors remains challenging in antitumor therapy. In this study, a covalent organic framework (COF)-based biomimetic nanomotor composed of polypyrrole (PPy) core, porphyrin-COF shell, and HCT116 cancer cell membrane coating is reported. Under near-infrared (NIR) light irradiation, the obtained mPPy@COF-Por can overcome Brownian motion and achieves directional motion through self-thermophoretic force generated from the PPy core. The HCT116 cancer cell membrane coating enables the nanomotor to selectively recognize the source cell lines and reduces the bio-adhesion of mPPy@COF-Por in a biological medium, endowing with this NIR light-powered nanomotor good mobility. More importantly, such multifunctional integration allows the COF-based nanomotor to be a powerful nanoagent for cancer treatment, and the high infrared thermal imaging/photoacoustic imaging/fluorescence trimodal imaging-guided combined photothermal/photodynamic therapeutic effect on HCT116 tumor cell is successfully achieved. The results offer considerable promise for the development of COF nanomotors with integrated imaging/therapy modalities in biomedical applications.


Assuntos
Estruturas Metalorgânicas , Neoplasias , Humanos , Polímeros , Pirróis/farmacologia , Medicina de Precisão , Neoplasias/terapia , Linhagem Celular Tumoral
20.
ACS Appl Mater Interfaces ; 14(3): 3900-3909, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35020367

RESUMO

The cell surface can be engineered with synthetic DNA for various applications ranging from cancer immunotherapy to tissue engineering. However, while elegant methods such as click conjugation and lipid insertion have been developed to engineer the cell surface with DNA, little effort has been made to systematically evaluate and compare these methods. Resultantly, it is often challenging to choose a right method for a certain application or to interpret data from different studies. In this study, we systematically evaluated click conjugation and lipid insertion in terms of cell viability, engineering efficiency, and displaying stability. Cells engineered with both methods can maintain high viability when the concentration of modified DNA is less than 25-50 µM. However, lipid insertion is faster and more efficient in displaying DNA on the cell surface than click conjugation. The efficiency of displaying DNA with lipid insertion is 10-40 times higher than that with click conjugation for a large range of DNA concentration. However, the half-life of physically inserted DNA on the cell surface is 3-4 times lower than that of covalently conjugated DNA, which depends on the working temperature. While the half-life of physically inserted DNA molecules on the cell surface is shorter than that of DNA molecules clicked onto the cell surface, lipid insertion is more effective than click conjugation in the promotion of cell-cell interactions under the two different experimental settings. The data acquired in this work are expected to act as a guideline for choosing an approximate method for engineering the cell surface with synthetic DNA or even other biomolecules.


Assuntos
Materiais Biocompatíveis/química , Engenharia Celular , DNA/química , Células Matadoras Naturais/química , Lipídeos/química , Comunicação Celular , Sobrevivência Celular , DNA/síntese química , Teste de Materiais , Estrutura Molecular
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