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1.
Sci Rep ; 12(1): 13479, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35931720

RESUMO

The relapsing fever agent Borrelia hermsii is transmitted by the tick Ornithodoros hermsi. To study the B. hermsii-tick interactions required for pathogen acquisition and transmission we developed an artificial membrane feeding system for O. hermsi nymphs and adults that results in a high percentage of engorgement. This system provides the nutritional requirements necessary for the tick to develop, mate, and produce viable eggs. By inoculating the blood with B. hermsii, we were able to obtain infected ticks for quantitative studies on pathogen acquisition and persistence. These ticks subsequently transmitted the spirochetes to mice, validating this system for both acquisition and transmission studies. Using this feeding method, a mutant of the antigenic variation locus of B. hermsii (Vmp-) that is incapable of persisting in mice was acquired by ticks at equivalent densities as the wild-type. Furthermore, Vmp is not required for persistence in the tick, as the mutant and wild-type strains are maintained at similar numbers after ecdysis and subsequent feeding. These results support the theory that Vmp is an adaptation for mammalian infection but unnecessary for survival within the tick. Interestingly, B. hermsii numbers severely declined after acquisition, though these ticks still transmitted the infection to mice. This procedure reduces animal use and provides a safe, highly controlled and well-contained alternative method for feeding and maintaining O. hermsi colonies. Importantly, this system permits quantitative studies with B. hermsii strains through ingestion during the blood meal, and thus more closely recapitulates pathogen acquisition in nature than other artificial systems.


Assuntos
Borrelia , Ornithodoros , Febre Recorrente , Spirochaeta , Animais , Borrelia/genética , Mamíferos , Membranas Artificiais , Camundongos
2.
Anal Chim Acta ; 1222: 339986, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35934419

RESUMO

Two modes of electromembrane extraction (EME) were evaluated in this work, one using deep eutectic solvents (DESs) as liquid membrane, and another was gel electromembrane extraction (G-EME) based on solid agarose membrane. Both EME modes have eliminated organic solvents and are recognized as green strategies. Unlike classic EME in which polypropylene membrane and organic extracting solvents play an essential role in the extraction process, new modes of EME are based on biodegradable membranes and aqueous extracting solutions. Approaches of EME based on the new designs follow the green chemistry principles. Each mode of EME was evaluated for the determination of polar and non-polar bases drugs from human urine samples using high-performance liquid chromatography (HPLC) equipped with a diode array detector (DAD). EME using DES A was suitable for determining polar and non-polar bases drugs in a large polarity window. While extraction recoveries for all six drugs studied by G-EME were lower than EME using DES A. Comparing the two EME modes shows similar results in the analytical figures of merit. However, differences in extraction recoveries of the drugs by two EME modes were observed which is related to the difference in membranes structure. Our findings indicate that the differences between membranes properties used in two EME modes, including the permeability, hydrophilicity, hydrophobicity, and variety of interactions, are influencer factors on extraction efficiency. The two EME modes provided good linearity in the ranges of 16-100 and 19-100 µg. L-1 for G-EME and EME using DES A, respectively with (r2 > 0.993). Also, the detection limits (LODs) were 19-32 and 19-29 µg. L-1 for G-EME and EME using DES A, respectively.


Assuntos
Solventes Eutéticos Profundos , Membranas Artificiais , Cromatografia Líquida de Alta Pressão , Humanos , Sefarose/química , Solventes/química
3.
Comput Intell Neurosci ; 2022: 3245014, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958742

RESUMO

Objective. To evaluate clinical efficacy and safety of absorbable and non-absorbable dental restorative membranes in guided bone regeneration (GBR). Articles concerning absorbable and non-absorbable prosthetic membrane-related studies of GBR were screened from multiple databases. In the end, 526 postoperative patients who met eligibility criteria were screened for the study from eight trials. The results showed that the repair success rate of the experimental group (absorbable dental restorative membrane) was higher than that of the control group (non-absorbable dental restorative membrane) (RR = 1.18, 95% CI [1.11,1.26], and the total physical therapy effect was P < 0.0001, I 2 = 0%), and the height of bone graft in the experimental group was higher than that in the control group (MD = 0.67, 95% CI [0.11, 1.23]). The thickness of bone graft in the experimental group was higher than that in the control group (MD = 0.43, 95% CI [0.30,0.56], P < 0.00001, I 2 = 61%), and the adverse events in the experimental group were less than those in the control group (RR = 0.31, 95% CI [0.18, 0.51], P < 0.00001, I 2 = 13%). Absorbable prosthetic membrane is superior to non-absorbable prosthetic membrane in clinical efficacy and safety.


Assuntos
Implantes Dentários , Regeneração Tecidual Guiada Periodontal , Implantes Absorvíveis , Regeneração Óssea , Implantes Dentários/efeitos adversos , Regeneração Tecidual Guiada Periodontal/métodos , Humanos , Membranas Artificiais , Resultado do Tratamento
4.
Langmuir ; 38(32): 9884-9891, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35921519

RESUMO

Although oil-water separation technology via wettability-controlled membranes has emerged as a promising technology to treat oily wastewater, membrane fouling by faulents such as sludge flocs and colloids, and the consequent clogging of pores, severely degrades the efficiency of filtration systems. One of the main promotors of fouling by faulents is oil fouling, which is also a form of fouling itself. Despite considerable practical and academic interest in the analysis of oil-fouled membranes, direct visualization of the entire process of oil infiltration into hydrophilic membranes is still preliminary owing to (i) the similar optical contrast and physical density between oil and water, (ii) the low penetration depth of imaging methods, and (iii) the lack of 3D segmentation capability. In this study, microcomputed X-ray tomography using tunable synchrotron radiation provided direct high-speed 3D visualization of the microscale dynamics of the oil infiltration of a prewetted hydrophilic filter membrane over time. Direct visualization of the interfacial dynamics of oil infiltration opens a window into the complex liquid (water/oil)-gas-solid interface and thus helps furnish an in-depth understanding of oil fouling in the prewetted membrane.


Assuntos
Purificação da Água , Membranas Artificiais , Óleos , Síncrotrons , Purificação da Água/métodos , Microtomografia por Raio-X
5.
Sci Rep ; 12(1): 13741, 2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-35962008

RESUMO

Microbial electrosynthesis (MES), is an emerging technology, for sustainable wastewater treatment. The dilute acetate solution, produced via MES, must be recovered, as dilute solutions can be expensive to store and transport. The acetate is expensive and environmentally damaging to recover by heat-intensive evaporative methods, such as distillation. In pursuit of a better energy economy, a membrane separation system is simulated to raise the concentration from 1 to 30 wt%, at a hydraulic pressure of approximately 50 bar. The concentrate is then simulated to be heat dried. Reverse osmosis (RO) could rase the acetate concentration to 8 wt%. A novel adaptation of osmotically assisted reverse osmosis (OARO) is then simulated to increase the concentration from 8 to 30 wt%. The inclusion of OARO, rather than a standalone RO unit, reduces the total heat and electric power requirement by a factor of 4.3. It adds to the membrane area requirement by a factor of 6. The OARO simulations are conducted by the internal concentration polarisation (ICP) model. Before the model is used, it is fitted to OARO experimental data, obtained from the literature. Membrane structure number of 701 µm and permeability coefficient of 2.51 L/m2/h/bar are ascertained from this model fitting exercise.


Assuntos
Membranas Artificiais , Purificação da Água , Destilação , Filtração , Osmose , Soluções
6.
Environ Sci Technol ; 56(14): 10279-10288, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35802136

RESUMO

The permeance and selectivity of a reverse osmosis (RO) membrane are governed by its ultrathin polyamide film, yet the growth of this critical film during interfacial polymerization (IP) has not been fully understood. This study investigates the evolution of a polyamide nanofilm at the aqueous/organic interface over time. Despite its thickness remaining largely constant (∼15 nm) for the IP reaction time ranging from 0.5 to 60 min, the density of the polyamide nanofilm increased from 1.25 to 1.36 g cm-3 due to the continued reaction between diffused m-phenylenediamine and dangling acyl chloride groups within the formed polyamide film. This continued growth of the polyamide nanofilm led to a simultaneous increase in its crosslinking degree (from 50.1 to 94.3%) and the healing of nanosized defects, resulting in a greatly enhanced rejection of 99.2% for NaCl without sacrificing water permeance. Using humic acid as a molecular probe for sealing membrane defects, the relative contributions of the increased crosslinking and reduced defects toward better membrane selectivity were resolved, which supports our conceptual model involving both enhanced size exclusion and healed defects. The fundamental insights into the growth mechanisms and the structure-property relationship of the polyamide nanofilm provide crucial guidance for the further development and optimization of high-performance RO membranes.


Assuntos
Nylons , Água , Filtração/métodos , Membranas Artificiais , Polimerização
7.
Int J Mol Sci ; 23(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35887303

RESUMO

Present research was directed towards the development of new high-performance and cost-effective polysulfone membranes (PSFQ) by introducing ionic liquids (ILs-Cyphos 101 IL and Aliquat 336) into their matrix. Variation of ILs was performed with the aim to find the one that brings new properties and improves the functionality and selectivity of PSFQ membranes in ultrafiltration processes. Based on the obtained results of the rheological study, we established the compatibility of compounds and optimal content of the used ILs, namely 3 wt% and 15 wt% Cyphos 101 IL and compositions varying between 3 and 15 wt % Aliquat 336. Results indicated that the ILs acted as plasticizers when they were added to the system, a helpful aspect in processing membranes used in water decontamination. The efficiency and performance of the membranes were evaluated by their use in the treatment of diclofenac (DCF)-containing waters. Membranes obtained from PSFQ/Aliquat 336 solution containing 15 wt% IL exhibited a 97% removal degree of DCF in the treatment process of 50 mL solution containing 3 mg/L DCF. The separation efficiency was kept constant for four filtration/cleaning cycles. The results indicated an improvement in membrane performance as the amount of IL in their structure increased, which confirms the potential for application in water treatment processes.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Membranas , Membranas Artificiais
8.
J Chromatogr A ; 1676: 463271, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35779390

RESUMO

In this study, the retention on three types of columns, an immobilized artificial membrane (IAM), a cholesterol-bonded and an octadecyl (C18) column, was applied for the prediction of skin permeability. The first two columns are biomimicking ones, which have certain components of the skin bound to the stationary phase, and were applied in HPLC, while the sub-2 µm C18 column was studied in UHPLC because of its fast features. Fifty-eight compounds were analyzed applying different mobile-phase compositions, with varying percentages of organic modifier on every column, to extrapolate the retention factor to a theoretically purely aqueous mobile phase (log kw). The retention factors, along with two sets of theoretical molecular descriptors, were used to model the skin permeability coefficient (log Kp) using multiple linear regression (MLR) and partial least squares (PLS) regression modelling. Although the retention factors (log k) on the IAM column showed a better correlation with the skin permeability, the overall best model was obtained by applying a stepwise MLR approach on the UHPLC parameters combined with some theoretical descriptors. This model showed a good fit, and on top has potential to accurately predict skin permeability values. Furthermore, the UHPLC method has the advantage of being fast and can thus be classified as a high-throughput approach.


Assuntos
Colesterol , Membranas Artificiais , Cromatografia Líquida de Alta Pressão/métodos , Permeabilidade , Preparações Farmacêuticas
9.
J Am Chem Soc ; 144(30): 13764-13772, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35866599

RESUMO

Introducing alien intercalations to sub-nanometer scale nanochannels is one desirable strategy to optimize the ion transportation of two-dimensional nanomaterial membranes for improving osmotic energy harvest (OEH). Diverse intercalating agents have been previously utilized to realize this goal in OEH, but with modest performance, complex operations, and physicochemical uncertainty gain. Here, we employ the self-exfoliation behavior of oxidative fragments (OFs) from graphene oxide basal plane under an alkaline environment to encapsulate detached OFs in nanochannels for breaking a trade-off between permeability and selectivity, boosting power density from 1.8 to 4.9 W m-2 with a cation selectivity of 0.9 and revealing a negligible decline in power density and trade-off during a long-term operation test (∼168 h). The strategy of membrane design, employing the intrinsically self-exfoliated OFs to decorate the nanochannels, provides an alternative and facile approach for ion separation, OEH, and other nano-fluidic applications.


Assuntos
Grafite , Membranas Artificiais , Osmose , Permeabilidade
10.
J Am Soc Mass Spectrom ; 33(8): 1510-1517, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35866646

RESUMO

Naphthenic acids comprise one of the most toxic compounds of the produced water released from offshore oil platforms. Therefore, developing and applying faster, simpler, and more efficient analytical methods for analyzing naphthenic acids are urgently needed. Electromembrane extraction (EME) uses the electrokinetic migration of target ions through a porous membrane. Herein, the EME method was applied to extract naphthenic acids from produced water. The EME method was optimized, and the optimal conditions encompassed decanol as the organic solvent, the sample with pH 10.0, 5 min of extraction at 200 V, and the ratio 4:1 (borate buffer/matrix, v/v). Electrochemical impedance spectroscopy confirmed charged species' migration from produced water through the EME. Subsequently, all extracts were analyzed by ultra-high-resolution mass spectrometry. The EME efficiency was assessed by comparing the extraction results to the liquid-liquid extraction (LLE) method results. Analytical results showed good linearity for both solvent and matrix curves (R2 > 0.98). Low detection limits ranged from 0.10 to 0.13 µg mL-1 and quantification limits from 0.36 to 0.45 µg mL-1. Precision and accuracy values ranged from -13.3% to 16.5%. These values fit the proposed method, demonstrating that the EME was more efficient than LLE in naphthenic acid extraction. The EME method preferably extracted aromatic compounds with double-bond equivalence from 6 to 8. The EME coupled with ultra-high-resolution mass spectrometry was demonstrated as a promising analytical approach to naphthenic acid extraction as an efficient and more environmentally friendly alternative to conventional extraction methods.


Assuntos
Membranas Artificiais , Água , Ácidos Carboxílicos , Espectrometria de Massas , Solventes/química , Água/química
11.
Environ Sci Technol ; 56(15): 10954-10962, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35819002

RESUMO

To enhance the use of nanofiltration in the production of quality drinking water, particularly through the efficient removal of micropollutants yet still preserving essential minerals, the targeted nanofiltration membranes (NFMs) are required to have small pore dimensions coupled with a high, net-negative charge density. Herein, after the formation of a separation layer using piperazine interfacially polymerized with trimesoyl chloride, the exploitation of residual amine groups was systematically investigated by different diacyl chlorides in an organic milieu, which caused the upper part of the final separation layer to be denser and highly negatively charged. Hence, this protocol offers a novel means to fabricate NFMs simultaneously endowed with a low molecular cutoff (MWCO) of 145-238 Da and a reduced rejection of MgCl2 (48%-80%) as well as a competitive water permeance. Those features are ideally applicable to the goal of removing small micropollutants while preserving mineral ions, as needed for the energy-efficient production of safe, quality drinking water. Furthermore, an attempt was made to correlate MWCO with MgCl2 rejection, which provides some insights on the nexus of the electrostatic effects constrained by size exclusion. The significance of residual amine groups and the modification environment was unveiled, and this method paves a new avenue for designing functional NFMs.


Assuntos
Água Potável , Nylons , Aminas , Cátions Bivalentes , Membranas Artificiais
12.
Int J Mol Sci ; 23(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35806220

RESUMO

The effect of the modification of the polyvinyl alcohol (PVA) selective layer of thin film composite (TFC) membranes by aluminosilicate (Al2O3·SiO2) nanoparticles on the structure and pervaporation performance was studied. For the first time, PVA-Al2O3·SiO2/polyacrylonitrile (PAN) thin film nanocomposite (TFN) membranes for pervaporation separation of ethanol/water mixture were developed via the formation of the selective layer in dynamic mode. Selective layers of PVA/PAN and PVA-Al2O3·SiO2/PAN membranes were formed via filtration of PVA aqueous solutions or PVA-Al2O3·SiO2 aqueous dispersions through the ultrafiltration PAN membrane for 10 min at 0.3 MPa in dead-end mode. Average particle size and zeta potential of aluminosilicate nanoparticles in PVA aqueous solution were analyzed using the dynamic light scattering technique. Structure and surface properties of membranes were studied using scanning electron microscopy (SEM), atomic force microscopy (AFM) and water contact angle measurements. Membrane performance was investigated in pervaporation dehydration of ethanol/water mixtures in the broad concentration range. It was found that flux of TFN membranes decreased with addition of Al2O3·SiO2 nanoparticles into the selective layer due to the increase in selective layer thickness. However, ethanol/water separation factor of TFN membranes was found to be significantly higher compared to the reference TFC membrane in the whole range of studied ethanol/water feed mixtures with different concentrations, which is attributed to the increase in membrane hydrophilicity. It was found that developed PVA-Al2O3·SiO2/PAN TFN membranes were more stable in the dehydration of ethanol in the whole range of investigated concentrations as well as at different temperatures of the feed mixtures (25 °C, 35 °C, 50 °C) compared to the reference membrane which is due to the additional cross-linking of the selective layer by formation hydrogen and donor-acceptor bonds between aluminosilicate nanoparticles and PVA macromolecules.


Assuntos
Nanopartículas , Álcool de Polivinil , Resinas Acrílicas , Silicatos de Alumínio , Desidratação , Etanol/química , Humanos , Membranas Artificiais , Álcool de Polivinil/química , Dióxido de Silício , Água/química
13.
J Virol ; 96(15): e0075122, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35867566

RESUMO

Lumpy skin disease virus (LSDV) is a poxvirus that causes severe systemic disease in cattle and is spread by mechanical arthropod-borne transmission. This study quantified the acquisition and retention of LSDV by four species of Diptera (Stomoxys calcitrans, Aedes aegypti, Culex quinquefasciatus, and Culicoides nubeculosus) from cutaneous lesions, normal skin, and blood from a clinically affected animal. The acquisition and retention of LSDV by Ae. aegypti from an artificial membrane feeding system was also examined. Mathematical models of the data were generated to identify the parameters which influence insect acquisition and retention of LSDV. For all four insect species, the probability of acquiring LSDV was substantially greater when feeding on a lesion compared with feeding on normal skin or blood from a clinically affected animal. After feeding on a skin lesion LSDV was retained on the proboscis for a similar length of time (around 9 days) for all four species and for a shorter time in the rest of the body, ranging from 2.2 to 6.4 days. Acquisition and retention of LSDV by Ae. aegypti after feeding on an artificial membrane feeding system that contained a high titer of LSDV was comparable to feeding on a skin lesion on a clinically affected animal, supporting the use of this laboratory model as a replacement for some animal studies. This work reveals that the cutaneous lesions of LSD provide the high-titer source required for acquisition of the virus by insects, thereby enabling the mechanical vector-borne transmission. IMPORTANCE Lumpy skin disease virus (LSDV) is a high consequence pathogen of cattle that is rapidly expanding its geographical boundaries into new regions such as Europe and Asia. This expansion is promoted by the mechanical transmission of the virus via hematogenous arthropods. This study quantifies the acquisition and retention of LSDV by four species of blood-feeding insects and reveals that the cutaneous lesions of LSD provide the high titer virus source necessary for virus acquisition by the insects. An artificial membrane feeding system containing a high titer of LSDV was shown to be comparable to a skin lesion on a clinically affected animal when used as a virus source. This promotes the use of these laboratory-based systems as replacements for some animal studies. Overall, this work advances our understanding of the mechanical vector-borne transmission of LSDV and provides evidence to support the design of more effective disease control programmes.


Assuntos
Ceratopogonidae , Doença Nodular Cutânea , Vírus da Doença Nodular Cutânea , Animais , Bovinos , Dietilamida do Ácido Lisérgico , Membranas Artificiais , Mosquitos Vetores
14.
Artigo em Inglês | MEDLINE | ID: mdl-35805879

RESUMO

Forward osmosis (FO) is an evolving membrane separation technology for water treatment and reclamation. However, FO water treatment technology is limited by factors such as concentration polarization, membrane fouling, and reverse solute flux. Therefore, it is of a great importance to prepare an efficient high-density porous membrane and to select an appropriate draw solute to reduce concentration polarization, membrane fouling, and reverse solute flux. This review aims to present a thorough evaluation of the advancement of different draw solutes and membranes with their effects on FO performance. NaCl is still widely used in a large number of studies, and several general draw solutes, such as organic-based and inorganic-based, are selected based on their osmotic pressure and water solubility. The selection criteria for reusable solutes, such as heat-recovered gaseous draw, magnetic field-recovered MNPs, and electrically or thermally-responsive hydrogel are primarily based on their industrial efficiency and energy requirements. CA membranes are resistant to chlorine degradation and are hydrophilic, while TFC/TFN exhibit a high inhibition of bio-adhesion and hydrolysis. AQPs are emerging membranes, due to proteins with complete retention capacity. Moreover, the development of the hybrid system combining FO with other energy or water treatment technologies is crucial to the sustainability of FO.


Assuntos
Membranas Artificiais , Purificação da Água , Osmose , Cloreto de Sódio , Soluções , Águas Residuárias
15.
Water Res ; 221: 118810, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35834972

RESUMO

Considerable attention has been paid in recent years to the recovery and effective utilization of organic matter in municipal wastewater for the establishment of a circular economy. Direct membrane filtration (DMF) of municipal wastewater using microfiltration (MF) or ultrafiltration (UF) membranes to retain and concentrate the organic matter in municipal wastewater could be a practical option for this purpose. However, severe membrane fouling and high concentrations of organic matter remaining in the DMF permeate are concerns to be addressed. Application of a simple pretreatment using fixed biofilms was investigated to address these issues. In this study, experiments were carried out at an existing municipal wastewater treatment plant. A moving bed biofilm reactor (MBBR) process operated under a very short HRT of 1 h and DO concentration of 0.5 mg/L selectively degraded low-molecular-weight dissolved organic matter in municipal wastewater without degradation of membrane-recoverable suspended and colloidal organic matter. Application of the pretreatment did not reduce the amount of organic carbon recovered by DMF using an MF membrane (approximately 70% of the influent COD being recovered), while it dramatically mitigated the membrane fouling probably due to the alteration of characteristics of dissolved organic matter in wastewater. The pretreatment also reduced the concentration of organic matter in the DMF permeate by 41%: COD concentration in the DMF permeate was as low as 40 mg/L. With the established MBBR pretreatment, performances of MF (0.1 µm) and UF (molecular weight cut-off: 150,000) membranes for DMF were compared in parallel. It was found that the increase of the recoverable amount of organic matter by using UF was marginal (about 5%), whereas fouling in UF was much more severe than that in MF. The severe fouling in UF was caused by inorganic colloids such as FeS that could pass through MF membranes but be retained by UF membranes. Based on the results obtained in this study, it is concluded that MF is more suitable than UF for efficient DMF.


Assuntos
Águas Residuárias , Purificação da Água , Biofilmes , Reatores Biológicos , Carbono , Filtração/métodos , Membranas Artificiais , Ultrafiltração/métodos , Purificação da Água/métodos
16.
Commun Biol ; 5(1): 745, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35879398

RESUMO

Extracellular mitochondria are present and act as non-cell-autonomous signals to support energetic homeostasis. While mitochondria allograft is a promising approach in rescuing neurons, glia, and vascular cells in CNS injury and disease, there are profound limitations in cellular uptake of mitochondria together with the efficacy. Here, we modified mitochondria by coating them with cationic DOTAP mixed with DOPE via a modified inverted emulsion method to improve mitochondrial transfer and efficacy. We initially optimized the method using control microbeads and liposomes followed by using mitochondria isolated from intact cerebral cortex of male adult C57BL/6J mice. After the coating process, FACS analysis indicated that approximately 86% of mitochondria were covered by DOTAP/DOPE membrane. Moreover, the artificial membrane-coated mitochondria (AM-mito) shifted the zeta-potential toward positive surface charge, confirming successful coating of isolated mitochondria. Mitochondrial proteins (TOM40, ATP5a, ACADM, HSP60, COX IV) and membrane potentials were well maintained in AM-mito. Importantly, the coating improved mitochondrial internalization and neuroprotection in cultured neurons. Furthermore, intravenous infusion of AM-mito immediately after focal cerebral ischemia-reperfusion amplified cerebroprotection in vivo. Collectively, these findings indicate that mitochondrial surface coating with artificial lipid membrane is feasible and may improve the therapeutic efficacy of mitochondria allograft.


Assuntos
Membranas Artificiais , Mitocôndrias , Animais , Lipídeos , Lipossomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo
17.
Environ Sci Technol ; 56(14): 10339-10348, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35786926

RESUMO

Biofouling in anaerobic membrane bioreactors (AnMBRs) has not been studied widely. Moreover, the effect of membrane surface properties on biofilm formation beyond initial deposition is controversial. We investigated biofouling with polyvinyldifluoride, polyacrylonitrile, and zwitterion-modified polyethersulfone ultrafiltration membranes having different properties during 72 h filtration using natural anaerobes isolated from AnMBR and analyzed biofilm characteristics by physicochemical and molecular techniques. A decrease in membrane performance was positively correlated with biofilm formation on polyvinyldifluoride and polyacrylonitrile membranes, and as expected, physical cleaning effectively mitigated biofilm on hydrophilic and low-roughness membranes. Surprisingly, while the biofilm on the hydrophilic and low-surface roughness zwitterion-modified membrane was significantly impaired, the impact on transmembrane pressure was the highest. This was ascribed to the formation of a soft compressible thin biofilm with high hydraulic resistance, and internal clogging and pore blocking due to high pore-size distribution. Anaerobe community analysis demonstrated some selection between the bulk and biofilm anaerobes and differences in the relative abundance of the dominant anaerobes among the membranes. However, correlation analyses revealed that all membrane properties studied affected microbial communities' composition, highlighting the system's complexity. Overall, our findings indicate that the membrane properties can affect biofilm formation and the anaerobic microbial population but not necessarily alleviate biofouling.


Assuntos
Incrustação Biológica , Anaerobiose , Bactérias Anaeróbias , Biofilmes , Reatores Biológicos , Membranas Artificiais , Ultrafiltração/métodos
18.
Water Res ; 221: 118752, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35810632

RESUMO

Organic matter (OM) in surface and ground waters may cause membrane fouling that is laborious to clean once established. Spontaneous osmotic backwash (OB) induced by solar irradiance fluctuation has been demonstrated for early mineral scaling/organic fouling control in decentralised small-scale photovoltaic powered-nanofiltration/reverse osmosis (PV-NF/RO) membrane systems. However, various OM types will interact differently with membranes which in turn affects the effectiveness of OB. This work evaluates the suitability of spontaneous OB cleaning for eleven OM types (covering low-molecular-weight organics (LMWO), humic substances, polyphenolic compounds and biopolymers) regarding adhesive interactions with NF/RO membranes. The adhesive interactions were quantified by an asymmetric flow field-flow fractionation coupled with an organic carbon detector (FFFF-OCD). The underlying mechanism of OM-membrane adhesive interactions affecting OB cleaning was elucidated. The results indicate that humic acid (a typical humic substance) and tannic acid (a typical polyphenolic compound) induced stronger adhesive interaction with NF/RO membranes than biopolymers and LMWO. When the mass loss of an OM due to adhesion was below a critical range, the spontaneous OB is most effective (>85% flux recovery); and above this range, the OB becomes ineffective (<50% flux recovery). Polyphenolic compounds and humic substances resulted in lower OB cleaning efficiency, due to their higher aromatic content, enhancing hydrophobic interactions and hydrogen bonding. Calcium-facilitated adhesion of some OM types (such as humic substances, polyphenolics and biopolymers) increased irreversible organic fouling potential and weakened OB cleaning, which was verified by both FFFF-OCD and membrane filtration results. This work provides a guidance to formulate strategies to enhance spontaneous OB cleaning, such as first identifying the adhesion of OM in feedwater (surface and ground waters) using FFFF-OCD, and then removing "sticky" OM using suitable pre-treatment processes.


Assuntos
Substâncias Húmicas , Purificação da Água , Adesivos , Membranas Artificiais , Osmose , Energia Renovável , Purificação da Água/métodos
19.
Bioresour Technol ; 360: 127542, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35777641

RESUMO

The seasonal and annual energy efficiency of mainstream anaerobic membrane bioreactor (AnMBR) was first assessed in an onsite pilot plant (15 m3/d) and then estimated in a scaled-up plant (10,000 m3/d) in temperate climates (15-25 °C). It was found that the annual net electricity demand was 0.100 and 0.090 kWh/m3, and the annual net energy (electricity + heat) demand was -0.158 and -0.309 kWh/m3 under the dissolved methane recovery condition and the non-recovery condition, respectively, demonstrated that the application of mainstream AnMBR in temperate climates is electricity saving and energy positive. The energy efficiency of the AnMBR decreased with temperature drop due to the reduction of methane production, and the increase in biogas sparging to mitigate membrane fouling. Since approximately 26.7%-39.7% of input COD remained in sludge, attention should be paid to recovering this potential energy to improve the overall energy performance of the mainstream AnMBR plants in future.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Anaerobiose , Reatores Biológicos , Conservação de Recursos Energéticos , Membranas Artificiais , Metano , Estações do Ano , Esgotos , Águas Residuárias/análise
20.
Bioresour Technol ; 360: 127628, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35850395

RESUMO

In this study, microbial fuel cells deploying heterogeneous ion exchange membranes were assessed. The behavior of the cells as a function of the membrane applied was evaluated in terms of maximal current density, electron recovery efficiency and energy production rate (up to 427.5 mA, 47.7 % and 660 J m-2h-1, respectively) at different substrate (acetate) feedings (2.15 - 8.6 mM). System performance was characterized in the light of oxygen and acetate crossovers. The effect of membranes (in relation to the oxygen mass transfer coefficient, kO) on the microbial diversity of anodic and membrane-surface biofilms was investigated. Based on the relative abundance of bacterial orders, the two populations could be distinguished and membranes with larger kO tended to promote more the air-tolerant microbes in the biofouling layer. This indicates that membrane kO has a direct effect on membrane foulant microbial composition, and thus, on the expected time-stability of the membrane.


Assuntos
Fontes de Energia Bioelétrica , Microbiota , Fontes de Energia Bioelétrica/microbiologia , Biofilmes , Eletrodos , Troca Iônica , Membranas Artificiais , Oxigênio
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