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1.
Molecules ; 29(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38611845

RESUMO

In this paper, berberine hydrochloride-loaded liposomes-in-gel were designed and developed to investigate their antioxidant properties and therapeutic effects on the eczema model of the mouse. Berberine hydrochloride-liposomes (BBH-L) as the nanoparticles were prepared by the thin-film hydration method and then dispersed BBH-L evenly in the gel matrix to prepare the berberine hydrochloride liposomes-gel (BBH-L-Gel) by the natural swelling method. Their antioxidant capacity was investigated by the free radical scavenging ability on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and H2O2 and the inhibition of lipid peroxides malondialdehyde (MDA). An eczema model was established, and the efficacy of the eczema treatment was preliminarily evaluated using ear swelling, the spleen index, and pathological sections as indicators. The results indicate that the entrapment efficiency of BBH-L prepared by the thin-film hydration method was 78.56% ± 0.7%, with a particle size of 155.4 ± 9.3 nm. For BBH-L-Gel, the viscosity and pH were 18.16 ± 6.34 m Pas and 7.32 ± 0.08, respectively. The cumulative release in the unit area of the in vitro transdermal study was 85.01 ± 4.53 µg/cm2. BBH-L-Gel had a good scavenging capacity on DPPH and H2O2, and it could effectively inhibit the production of hepatic lipid peroxides MDA in the concentration range of 0.4-2.0 mg/mL. The topical application of BBH-L-Gel could effectively alleviate eczema symptoms and reduce oxidative stress injury in mice. This study demonstrates that BBH-L-Gel has good skin permeability, excellent sustained release, and antioxidant capabilities. They can effectively alleviate the itching, inflammation, and allergic symptoms caused by eczema, providing a new strategy for clinical applications in eczema treatment.


Assuntos
Berberina , Eczema , Animais , Camundongos , Antioxidantes/farmacologia , Berberina/farmacologia , Lipossomos , Peróxido de Hidrogênio , Peróxidos Lipídicos
2.
Biopolymers ; 114(7): e23554, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37232459

RESUMO

The regulation of the biodegradation rate of 3D-regenerated silk fibroin scaffolds and the avoidance of premature collapse are important concerns for their effective applications in tissue engineering. In this study, bromelain, which is specific to sericin, was used to remove sericin from silk, and high molecular weight silk fibroin was obtained after the fibroin fibers were dissolved. Afterwards, a 3D scaffold was prepared via freeze-drying. The Sodium dodecyl sulfate-polyacrylamide gel electrophoresis results showed that the average molecular weight of the regenerated silk fibroin prepared by using the bromelain-degumming method was approximately 142.2 kDa, which was significantly higher than that of the control groups prepared by using the urea- and Na2 CO3 -degumming methods. The results of enzyme degradation in vitro showed that the biodegradation rate and internal three-dimensional structure collapse of the bromelain-degumming fibroin scaffolds were significantly slower than those of the two control scaffolds. The proliferation activity of human umbilical vein vascular endothelial cells inoculated in bromelain-degumming fibroin scaffolds was significantly higher than that of the control scaffolds. This study provides a novel preparation method for 3D-regenerated silk fibroin scaffolds that can effectively resist biodegradation, continuously guide cell growth, have good biocompatibility, and have the potential to be used for the regeneration of various connective tissues.


Assuntos
Fibroínas , Sericinas , Humanos , Fibroínas/química , Alicerces Teciduais/química , Bromelaínas , Materiais Biocompatíveis/química , Sericinas/química , Peso Molecular , Células Endoteliais/metabolismo , Engenharia Tecidual/métodos , Seda/química , Proliferação de Células
3.
BMC Oral Health ; 23(1): 141, 2023 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-36906526

RESUMO

BACKGROUND: Intrafibrillar remineralization within the hybrid layers (HLs) has recently attracted extensive attention in achieving durable resin-dentin bonds. The polyhydroxy-terminated poly(amidoamine) dendrimer (PAMAM-OH) at fourth generation becomes a desirable candidate to induce intrafibrillar remineralization to protect exposed collagen fibrils within HLs based on the size exclusion effect of fibrillar collagen. However, the remineralization process in vivo is time-consuming, during which the exposed collagen fibrils are vulnerable to enzymatic degradation, resulting in unsatisfactory remineralization. Thereby, if PAMAM-OH itself possesses concomitant anti-proteolytic activity during the induction of remineralization, it would be very beneficial to obtain satisfactory remineralization. METHODS: Binding capacity tests using adsorption isotherm and confocal laser scanning microscopy (CLSM) were performed to assess if the PAMAM-OH had adsorption capacity on dentin. Anti-proteolytic testings were detected by MMPs assay kit, in-situ zymography and ICTP assay. Adhesive infiltration of resin-dentin interface and tensile bond strength before and after thermomechanical cycling were implemented to assess if the PAMAM-OH adversely affected resin-dentin bonds. RESULTS: Anti-proteolytic testings performed using MMPs assay kit, in-situ zymography and ICTP assay indicated that PAMAM-OH inhibited exogenous soluble MMP-9 as well as had inhibitory effect on the endogenous proteases. Adhesive infiltration of resin-dentin interface and tensile bond strength before and after thermomechanical cycling were implemented to indicate that the PAMAM-OH pretreatment had no adverse effects on immediate dentin bonding and prolonged the durability of resin-dentin bonds. CONCLUSIONS: PAMAM-OH possesses anti-proteolytic activity and prevents exposed collagen fibrils within HLs from degradation, which lays the foundation for the satisfactory intrafibrillar remineralization induced by PAMAM-OH within HLs to achieve durable resin-dentin bonds in the next work.


Assuntos
Dendrímeros , Colagem Dentária , Colágeno/metabolismo , Dendrímeros/análise , Dendrímeros/metabolismo , Colagem Dentária/métodos , Dentina/metabolismo , Adesivos Dentinários/química , Teste de Materiais , Metaloproteinases da Matriz/metabolismo , Resistência à Tração
4.
Anal Bioanal Chem ; 414(5): 2009-2019, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35048136

RESUMO

A simple rhodamine-based compound CK was designed and synthesized as a fluorescent chemosensor for Sn2+ based on Sn2+-mediated cyclization. The optical investigation indicated that the probe could quantitatively detect Sn2+ in a concentration range of 10-30 µM, with a detection limit of 118 nM. Moreover, probe CK, with low cytotoxicity, was successfully applied for imaging of Sn2+ in HeLa cells and mice, exhibiting excellent biocompatibility and cell membrane permeability. For on-site monitoring, CK-hybridized polymethyl methacrylate (PMMA) nanofibers were prepared by electrospinning and successfully employed for the visual detection of Sn2+ in actual samples. All the results demonstrated that the chemosensor could be a promising tool for the detection of Sn2+ in vitro and in vivo.


Assuntos
Nanofibras/química , Rodaminas/química , Estanho/análise , Animais , Diagnóstico por Imagem , Células HeLa , Humanos , Limite de Detecção , Camundongos , Polimetil Metacrilato/química
5.
J Oral Rehabil ; 49(5): 495-504, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35158405

RESUMO

BACKGROUND: Obstructive sleep apnea (OSA) is associated with increases in QT interval corrected for heart rate (QTc interval) and QT variability index (QTVI) and sleep bruxism (SB) is prevalent in OSA patients. OBJECTIVES: To examine whether QTc interval and QT variability were changed during episodes of rhythmic masticatory muscle activities (RMMAs)/SB in SB patients with and without OSA. METHODS: The RR and QTc intervals, and QTVI during RMMAs with or without accompanied limb movements (RMMAs/LMs) in 10 normal controls and 10 SB patients without OSA and during apneic and recovery periods of OSA in 10 SB patients with OSA were analysed. RESULTS: In the SB patients without OSA and controls, QTc intervals and QTVI were significantly increased during RMMAs/LMs compared with those during the 10 s periods (from 10th to 20th s) before the onset and after the offset of RMMAs/LMs, and significantly increased during RMMAs/LMs with awakenings compared with those with microarousals and no arousals. In addition, QTc interval and QTVI were positively correlated with the duration of RMMAs/LMs. Moreover, in the SB patients with OSA, QTc interval and QTVI during the recovery period of OSA events were significantly longer and higher than those during the apneic period regardless of accompanied RMMAs/LMs, and QTc interval and QTVI during the apneic and recovery periods accompanied with RMMAs/LMs were significantly longer and higher than those without accompanied RMMAs/LMs. CONCLUSION: OSA and RMMAs/LMs events were associated with longer QTc intervals and higher QTVI, and RMMAs/LMs might contribute to these changes associated with OSA events accompanied with RMMAs/LMs.


Assuntos
Apneia Obstrutiva do Sono , Bruxismo do Sono , Eletrocardiografia , Humanos , Projetos Piloto , Polissonografia , Apneia Obstrutiva do Sono/complicações , Bruxismo do Sono/complicações
6.
Biomacromolecules ; 20(7): 2821-2829, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31244022

RESUMO

Glycogen, a randomly branched glucose polymer, provides energy storage in organisms. It forms small ß particles which in animals bind to form composite α particles, which give better glucose release. Simulations imply ß particle size is controlled only by activities and sizes of glycogen biosynthetic enzymes and sizes of polymer chains. Thus, storing more glucose requires forming more ß particles, which are expected to sometimes form α particles. No α particles have been reported in bacteria, but the extraction techniques might have caused degradation. Using milder glycogen extraction techniques on Escherichia coli, transmission electron microscopy and size-exclusion chromatography showed α particles, consistent with this hypothesis for α-particle formation. Molecular density and size distributions show similarities with animal glycogen, despite very different metabolic processes. These general polymer constraints are such that any organism which needs to store and then release glucose will have similar α and ß particle structures: a type of convergent evolution.


Assuntos
Escherichia coli/química , Glucose/química , Glicogênio/química , Polímeros/química , Partículas alfa , Partículas beta , Metabolismo Energético/genética , Escherichia coli/ultraestrutura , Glicogênio/ultraestrutura , Microscopia Eletrônica de Transmissão
7.
Environ Geochem Health ; 40(6): 2441-2452, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29691784

RESUMO

Concentrations of eight trace metals (TMs) in road dust (RD) (particles < 25 µm) from urban areas of Xinxiang, China, were determined by inductively coupled plasma mass spectrometry. The geometric mean concentrations of Zn, Mn, Pb, As, Cu, Cr, Ni and Cd were 489, 350, 114, 101, 60.0, 39.7, 31.6, and 5.1 mg kg-1, respectively. When compared with TM levels in background soil, the samples generally display elevated TM concentrations, except for Cr and Mn, and for Cd the enrichment value was 69.6. Spatial variations indicated TMs in RD from park path would have similar sources with main roads, collector streets and bypasses. Average daily exposure doses of the studied TMs were about three orders of magnitude higher for hand-to-mouth ingestion than dermal contact, and the exposure doses for children were 9.33 times higher than that for adults. The decreasing trend of calculated hazard indexes (HI) for the eight elements was As > Pb > Cr > Mn > Cd > Zn > Ni > Cu for both children and adults.


Assuntos
Arsênio/análise , Poeira/análise , Monitoramento Ambiental , Metais Pesados/análise , Oligoelementos/análise , China , Cidades , Humanos , Tamanho da Partícula , Medição de Risco
8.
Anal Chem ; 89(7): 4184-4191, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28276243

RESUMO

Accurate quantification of nonspecific protein adsorption on biomaterial surfaces is essential for evaluation of their antifouling properties. The quartz crystal microbalance (QCM) is an acoustic sensor widely used for the measurement of protein adsorption. However, although the QCM is highly sensitive, it does have performance limitations when working with surfaces modified with thick viscous layers. In the case of polymer brush surfaces, factors such as the thickness and viscosity of the brush may bring such limitations. In the present work, three types of antifouling molecules were used to explore the applicability of QCM for the evaluation of the protein resistance of hydrophilic polymer brush surfaces. Adsorption was also measured by surface plasmon resonance (SPR) as a reference. It was shown that the detection of adsorbed protein requires that protein be located within a critical distance from the QCM chip surface, determined by the viscosity of polymer brush. For larger proteins like fibrinogen, adsorption is expected to occur mainly "on top" of the polymer brush, and brush thickness determines whether protein is located in the "detectable zone". For smaller proteins like lysozyme, adsorption is expected to occur mainly at the chip surface and within the polymer brush layer and to be detectable by QCM. However, the quantity of adsorbed lysozyme may be underestimated when secondary adsorption also occurred. It is concluded that QCM data suggesting very low protein adsorption on polymer brush surfaces should take account of these considerations and should be treated generally with caution.


Assuntos
Fibrinogênio/química , Muramidase/química , Polímeros/química , Técnicas de Microbalança de Cristal de Quartzo , Adsorção , Muramidase/metabolismo , Tamanho da Partícula , Ressonância de Plasmônio de Superfície , Propriedades de Superfície , Viscosidade
9.
Ann Hepatol ; 15(4): 482-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27236147

RESUMO

UNLABELLED:  Introduction. Oxymatrine (OMTR) is widely used for the treatment of chronic hepatitis B (CHB) in China. Several recent reports revealed that OMTR together with interferon yielded a higher sustained virological response (SVR) than interferon alone. AIM: To elucidate this topic using meta-analysis of data from published randomized controlled trials (RCTs). MATERIAL AND METHODS: The Cochrane Central Register of Controlled Trials, Medline, Science Citation Index, EMBASE, China National Knowledge Infrastructure, Wanfang Database and China Biomedical Database were searched to identify RCTs that evaluated SVR to interferón therapies and interferon plus OMTR therapies in CHB patients. RESULTS: The literature search yielded 238 studies, and 11 RCTs comprising 968 patients matched the selection criteria. Overall, SVR was significantly higher in patients treated with interferon plus OMTR than in patients treated with interferon alone (SVR: 60.7 vs. 39.8%; relative risk: 1.56; 95% confidence interval: 1.37-1.77; p < 0.05). Combined therapy of interferon plus OMTR were also superior to interferon therapies alone in achieving the endof-treatment viral response, alaninetransaminase normalization, HBeAg loss, and HBeAg seroconversion. CONCLUSIONS: Combined therapy of interferon plus OMTR may yield a higher SVR than interferon therapies. The exact outcome needs to perform rigorously designed, multicenter, and large randomized controlled trials.


Assuntos
Alcaloides/uso terapêutico , Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Quinolizinas/uso terapêutico , DNA Viral/sangue , Quimioterapia Combinada , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/genética , Hepatite B Crônica/sangue , Hepatite B Crônica/imunologia , Humanos , Interferons/uso terapêutico , Polietilenoglicóis/uso terapêutico , Resposta Viral Sustentada
10.
Langmuir ; 30(2): 501-8, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24377837

RESUMO

The adsorption of lysozyme is difficult to control by pH because of the relatively high isoelectric point of this protein (11.1). In this article, we demonstrate good control of lysozyme adsorption by pH in the range of 4-10 on silicon surfaces through modification with poly(2-(dimethylamino ethyl) methacrylate)-block-poly(methacrylic acid) (PDMAEMA-b-PMAA) diblock copolymer brushes. We show that the thickness of the outer PMAA block (lPMAA) is critical to the adsorption. When lPMAA was less than 10 nm, adsorption increased with increasing pH, and the difference in adsorption between high and low pH increased with lPMAA. The ratio of adsorption at pH 10 and pH 4 reached values as high as 16.4. When lPMAA was more than 10 nm, the adsorption tendency on the PDMAEMA-b-PMAA diblock copolymer brushes was similar to that on PMAA homopolymer brushes. These results indicate that the combination of PDMAEMA and PMAA gives adsorption behavior reflecting the properties of both polymers. However, if the outer PMAA block is thicker than a critical value, then the protein-resistant effect of the inner PDMAEMA block is screened.


Assuntos
Muramidase/química , Ácidos Polimetacrílicos/química , Adsorção , Concentração de Íons de Hidrogênio , Muramidase/metabolismo , Tamanho da Partícula , Propriedades de Superfície
11.
Int J Biol Macromol ; 255: 128185, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37977456

RESUMO

Chitosan and cellulose nanofiber films are frequently employed as biodegradable materials for food packaging. However, many exhibit suboptimal hydrophobicity and antioxidant properties. To address these shortcomings, we enhanced the performance by adding different concentrations of soybean protein isolate (SPI) to chitosan-cellulose nanofiber (CS-CNF) films. As SPI concentration varied, the turbidity, particle size, and ζ-potential of the film-forming solutions initially decreased and subsequently increased. This suggests that 1 % SPI augments the electrostatic attraction and compatibility. Rheological analysis confirmed a pronounced apparent viscosity at this concentration. Analyses using Fourier transform infrared spectra, Raman spectra, X-ray diffraction, and Scanning electron microscope revealed the presence of hydrogen bonds and electrostatic interactions between SPI and CS-CNF, indicative of superior compatibility. When SPI concentration was set at 1 %, notable enhancements in film attributes were observed: improvements in tensile strength and elongation at break, a reduction in water vapor permeability by 8.23 %, and an elevation in the contact angle by 18.85 %. Furthermore, at this concentration, the ABTS+ and DPPH scavenging capacities of the film surged by 61.53 % and 46.18 %, respectively. Meanwhile, the films we prepare are not toxic. This research offers valuable insights for the advancement and application of protein-polysaccharide-based films.


Assuntos
Quitosana , Filmes Comestíveis , Nanofibras , Quitosana/química , Proteínas de Soja/química , Celulose , Nanofibras/química , Resistência à Tração , Permeabilidade , Embalagem de Alimentos
12.
J Control Release ; 365: 176-192, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992873

RESUMO

Coacervate droplets formed by liquid-liquid phase separation have attracted considerable attention due to their ability to enrich biomacromolecules while preserving their bioactivities. However, there are challenges to develop coacervate droplets as delivery vesicles for therapeutics resulting from the lack of physiological stability and inherent lack of membranes in coacervate droplets. Herein, polylysine-polynucleotide complex coacervate droplets with favorable physiological stability are formulated to efficiently and facilely concentrate small molecules, biomacromolecules and nanoparticles without organic solvents. To improve the biocompatibility, the PEGylated phospholipid membrane is further coated on the surface of the coacervate droplets to prepare coacervate-based artificial protocells (ArtPC) with membrane-like and cytoplasm-like structures. The ArtPC can confine the cyclic catalytic system of uricase and catalase inside to degrade uric acid and deplete the toxicity of H2O2. This biofunctional ArtPC effectively reduces blood uric acid levels and prevents renal injuries in mice with persistent hyperuricemia. The ArtPC-based therapy can bridge the disciplines of synthetic biology, pharmaceutics and therapeutics.


Assuntos
Células Artificiais , Hiperuricemia , Animais , Camundongos , Células Artificiais/química , Células Artificiais/metabolismo , Hiperuricemia/tratamento farmacológico , Ácido Úrico , Peróxido de Hidrogênio , Citoplasma
13.
Enzyme Microb Technol ; 173: 110376, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38096655

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) can improve the effectiveness with which agricultural waste is utilized. This study described the potent AA9 family protein MsLPMO3, derived from Morchella sextelata. It exhibited strong binding to phosphoric acid swollen cellulose (PASC), and had the considerable binding ability to Cu2+ with a Kd value of 2.70 µM by isothermal titration calorimetry (ITC). MsLPMO3 could also act on PASC at the C1 carbon via MALDI-TOF-MS results. Moreover, MsLPMO3 could boost the hydrolysis efficiency of corncob and wheat bran in combination with glycoside hydrolases. MsLPMO3 also exhibited strong oxidizing ability for 2,6-dimethoxyphenol (2,6-DMP), achieving the best Vmax value of 443.36 U·g-1 for pH 7.4 with a H2O2 concentration of 300 µM. The structure of MsLPMO3 was obtained using AlphaFold2, and the molecular docking results elucidated the specific interactions and key residues involved in the recognition process between MsLPMO3 and cellulose. Altogether, this study expands the knowledge of AA9 family proteins in cellulose degradation, providing valuable insights into the mechanisms of synergistic degradation of lignocellulose with cellulases.


Assuntos
Celulose , Oxigenases de Função Mista , Celulose/metabolismo , Oxigenases de Função Mista/metabolismo , Simulação de Acoplamento Molecular , Peróxido de Hidrogênio/metabolismo , Polissacarídeos/metabolismo , Oxirredução , Estresse Oxidativo
14.
Langmuir ; 29(4): 1122-8, 2013 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-23265296

RESUMO

Polymer brush layers based on block copolymers of poly(oligo(ethylene glycol) methacrylate) (POEGMA) and poly(glycidyl methacrylate) (PGMA) were formed on silicon wafers by activators generated by electron transfer atom transfer radical polymerization (AGET ATRP). Different types of biomolecule can be conjugated to these brush layers by reaction of PGMA epoxide groups with amino groups in the biomolecule, while POEGMA, which resists nonspecific protein adsorption, provides an antifouling environment. Surfaces were characterized by water contact angle, ellipsometry, and Fourier transform infrared spectroscopy (FTIR) to confirm the modification reactions. Phase segregation of the copolymer blocks in the layers was observed by AFM. The effect of surface properties on protein conjugation was investigated using radiolabeling methods. It was shown that surfaces with POEGMA layers were protein resistant, while the quantity of protein conjugated to the diblock copolymer modified surfaces increased with increasing PGMA layer thickness. The activity of lysozyme conjugated on the surface could also be controlled by varying the thickness of the copolymer layer. When biotin was conjugated to the block copolymer grafts, the surface remained resistant to nonspecific protein adsorption but showed specific binding of avidin. These properties, that is, well-controlled quantity and activity of conjugated biomolecules and specificity of interaction with target biomolecules may be exploited for the improvement of signal-to-noise ratio in sensor applications. More generally, such surfaces may be useful as biological recognition elements of high specificity for functional biomaterials.


Assuntos
Anti-Infecciosos/química , Fibrinogênio/química , Proteínas Imobilizadas/química , Metacrilatos/química , Muramidase/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Adsorção , Avidina/química , Biotina/química , Transporte de Elétrons , Microscopia de Força Atômica , Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Água/química
15.
J Hazard Mater ; 441: 129820, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36103762

RESUMO

It is difficult to dispose diethylhexyl phthalate-rich polyvinyl chloride (DEHP-rich PVC) waste due to the high level of chlorine and plasticizer. On the other hand, the denitrification of urine wastewater with high nitrogen content also faces great challenges. In this study, a synergistic treatment strategy was developed for the DEHP-rich PVC waste and urine wastewater by a subcritical water process. Subcritical urine wastewater (SUW) was used as a reaction medium in the synergistic treatment. PVC dechlorination, DEHP decomposition, and denitrification of urine wastewater were synchronously achieved in the one pot SUW. Under the optimal conditions (300 °C, 15 min, 1:5 g/mL), the PVC dechlorination ratio, urine wastewater denitrification ratio and DEHP decomposition ratio could reach 98.4%, 64.9%, and 99.2%, respectively. The decomposition of DEHP mainly included hydrolysis, nucleophilic substitution, and acylation. DEHP could be converted into phthalic acid crystal at 220 °C with a yield of 66.25% due to the efficient hydrolysis action of SUW. All the removed Cl was transferred from PVC matrix to aqueous phase. Hydroxyl nucleophilic substitution is the principal dechlorination path of PVC. The reactions between N-containing species and DEHP in SUW resulted in the high-efficiency denitrification of urine wastewater, and the N element was fixed in solid residue or transferred to oil phase as amides compounds. It is believed that the proposed SUW process is a promising technology for the synergistic treatment of DEHP-rich PVC waste and urine wastewater.


Assuntos
Dietilexilftalato , Plastificantes , Amidas , Cloro , Desnitrificação , Dietilexilftalato/química , Nitrogênio , Ácidos Ftálicos , Cloreto de Polivinila/química , Águas Residuárias , Água
16.
Colloids Surf B Biointerfaces ; 224: 113210, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36841206

RESUMO

Reducing the cytotoxicity of cationic polymers is the major issue to their use as a gene delivery carrier. In this study, plasmids containing encoding vascular endothelial cell growth factor 165 and angiopoietin-1 were packaged with the conjugates of cationic fibroin (CSF) and polyethylenimine (PEI), instead of packaging pDNA with PEI alone, to prepare nanocomplexes (CSF+PEI)/pDNA. The complexes were loaded into a silk fibroin scaffold to enhance its function to induce microvascular network generation and dermal tissue regeneration. The results of transfecting EA.hy926 cells with the complexes in vitro showed that (CSF+PEI)/pDNA had a stronger transfection ability than PEI/pDNA. Importantly, compared with PEI as the gene carrier alone, the cell viability was significantly increased and the cytotoxicity was effectively reduced after the conjugate of CSF and PEI was used as the gene carrier. The results of angiogenesis in chick embryo chorioallantoic membranes showed that compared with scaffolds loaded with PEI/pDNA, the neovascularization ratio in scaffolds loaded with (CSF+PEI)/pDNA was significantly increased. In vivo experimental results of scaffolds implantation for full-thickness skin defects in SD rats showed that, compared with loading PEI/pDNA complex, loading (CSF+PEI)/pDNA complex in the scaffold more effectively promoted the formation of vascular network in the scaffold and accelerated the regeneration of dermal tissue. The gene delivery system established in this study has application potential not only in the regeneration of vascular-containing tissues, but also in tumor gene therapy.


Assuntos
Fibroínas , Polietilenoimina , Ratos , Embrião de Galinha , Animais , Polietilenoimina/farmacologia , Fibroínas/farmacologia , DNA/genética , Angiopoietina-1/genética , Ratos Sprague-Dawley , Plasmídeos/genética , Transfecção , Técnicas de Transferência de Genes
17.
NPJ Biofilms Microbiomes ; 9(1): 45, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37400465

RESUMO

The oral cavity harbors highly diverse communities of microorganisms. However, the number of isolated species and high-quality genomes is limited. Here we present a Cultivated Oral Bacteria Genome Reference (COGR), comprising 1089 high-quality genomes based on large-scale aerobic and anaerobic cultivation of human oral bacteria isolated from dental plaques, tongue, and saliva. COGR covers five phyla and contains 195 species-level clusters of which 95 include 315 genomes representing species with no taxonomic annotation. The oral microbiota differs markedly between individuals, with 111 clusters being person-specific. Genes encoding CAZymes are abundant in the genomes of COGR. Members of the Streptococcus genus make up the largest proportion of COGR and many of these harbor entire pathways for quorum sensing important for biofilm formation. Several clusters containing unknown bacteria are enriched in individuals with rheumatoid arthritis, emphasizing the importance of culture-based isolation for characterizing and exploiting oral bacteria.


Assuntos
Bactérias , Microbiota , Humanos , Boca/microbiologia , Saliva/microbiologia , Streptococcus
18.
Waste Manag ; 153: 397-404, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36202048

RESUMO

Waste liquid crystal displays (LCD) contain a large number of organic compounds such as cellulose triacetate (CTA), poly(vinyl alcohol) (PVA), triphenyl phosphate (TPP), and liquid crystal (LC). It is important to recover organic compounds from waste LCD due to their value and environmental toxicity. However, it is challenging to recover organic compounds from waste LCD because of the heterogeneous mixture of glass, organics and metals contained therein. In this study, an environment-friendly near/supercritical methanol (NSCM) process was developed as a closed cycle technology for the conversion of organic compounds from waste LCD. The acid-base catalytic activity and nonpolar property of the NSCM could efficiently promote the conversion of organic compounds from waste LCD. TPP could be extracted below 200 °C in the NSCM process. Below 250 °C, the conversion ratio of organic compounds from waste LCD ranged from 5 % to 68 % due to the extraction or decomposition of TPP, LC, and PVA. The main products obtained at 250 °C included long-chain alcohols and alkanes with a similar composition to industrial liquid paraffin, which could be widely used in other industrial processes. Under the optimal operation parameters (300 °C, 30 min, and 1:20 g/ml), the conversion ratio of organic compounds could reach 98 % due to the efficient decomposition of CTA. The main products obtained included ketones and esters chemicals, which could be further used as a chemical feedstock. No secondary pollutant was generated in the whole process. The low-boiling methanol could easily be recycled, which could make the NSCM a clean process for the production of high value-added organic products from waste LCD.


Assuntos
Poluentes Ambientais , Cristais Líquidos , Alcanos , Poluentes Ambientais/química , Cetonas , Cristais Líquidos/química , Metanol , Óleo Mineral , Organofosfatos , Álcool de Polivinil
19.
ACS Biomater Sci Eng ; 8(5): 1867-1877, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35384655

RESUMO

Flexible electronic devices with biological therapeutic and sensing properties are one of the current research directions. Here, a multifunctional hydrogel for stress sensing and wound healing was prepared by a simple one-pot method and a solution replacement method. Among them, zwitterionic polymers promote wound healing by promoting the polarization of M2 macrophages, collagen deposition, and blood vessel formation. Glycerin can significantly improve the resilience and frost resistance of the hydrogel, ensuring that a sensor made using the hydrogel can work normally in a cold environment. In addition, zwitterionic polymers are highly biocompatible, providing excellent antibacterial adhesion to aid the wound healing process, and good electrical conductivity enhances sensing sensitivity and stability. Based on these properties, multifunctional hydrogels could detect human vital activities while promoting wound healing, providing new ideas for the fields of diagnosis and wound dressing.


Assuntos
Incrustação Biológica , Hidrogéis , Incrustação Biológica/prevenção & controle , Condutividade Elétrica , Humanos , Hidrogéis/farmacologia , Polímeros , Cicatrização
20.
Bioresour Technol ; 354: 127195, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35452824

RESUMO

The present study investigated the effects of separately or simultaneously inoculating thermophilic fungus Aspergillus fumigatus Z5 and bacterium Geobacillus stearothermophilus B5 on lignocellulose degradation, enzyme activities and humification during rice straw composting. The results indicated that inoculation of Z5 accelerated the rise of temperature in the mesophilic phase, and the degradation degree of cellulose and hemicellulose was increased by 25.3% and 20.7%, respectively, due to the higher activities of lignocellulolytic enzymes. Inoculation of B5 increased 5-7 °C of the compost temperature in the thermophilic phase, and also prolonged the duration from 33 to 41 days. Inoculated simultaneously, the secreted hydrolases of Z5 generated more nutrition and promoted the growth of B5. B5 maintained and increased the compost temperature, thus presenting a better hydrolysis environment for extracellular hydrolases. Thermophilic inoculation altered the main physicochemical factors and improved efficiency and maturity in rice straw composting.


Assuntos
Compostagem , Oryza , Bactérias , Celulose , Hidrolases , Solo
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