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1.
Anal Chem ; 94(18): 6827-6832, 2022 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-35471823

RESUMEN

The biomineralized metal-organic frameworks (MOFs) as protective layers help enhance the robustness of enzymes for biocatalysis. Despite great efforts, it is still challenging to develop a recyclable system with high payload and tolerance to harsh conditions. Here, we report a facile surface charge-independent strategy based on Zn-based coordination polymer (ZnCP) for nondestructive immobilization of enzyme. The ZnCP outcompetes most of the previously reported MOFs, in terms of high-payload enzyme packaging. Moreover, benefiting from the hydrophilicity of ZnCP, the entrapped enzymes (e.g., positive cytochrome C and negative glucose oxidase) maintained high catalytic activity, resembling their native counterparts. Notably, compared with ZIF-8, such enzyme-incorporated ZnCP (enzyme@ZnCP) is more tolerant to acidic pH, which imparts the enzyme with good recyclability, even in acid species-generated catalytic reactions, thus broadening its application in biocatalysis. The feasibility of enzyme@ZnCP for protein packaging, enzyme cascade catalysis, and biosensing was also validated. Altogether, enzyme@ZnCP demonstrates high enzyme payload, operational stability, and preservation of enzymatic activity, affording a versatile platform to accommodate bioactive enzyme for biocatalysis and biosensing.


Asunto(s)
Estructuras Metalorgánicas , Polímeros , Biocatálisis , Enzimas Inmovilizadas/metabolismo , Glucosa Oxidasa/metabolismo , Estructuras Metalorgánicas/metabolismo , Metales , Polímeros/metabolismo
2.
BMC Plant Biol ; 22(1): 311, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35761174

RESUMEN

BACKGROUND: The tradeoff between negative and positive interactions of facilitated species and facilitators may depend on the degree of resource availability in agroecosystems. However, the rhizospheric mechanisms driving trade-offs that occur along phosphorus (P) and water availability gradients have not yet been systematically clarified. We established three types of root isolation conditions (no barrier, nylon barrier and solid barrier) at different P and water addition levels to address the above issue in a maize-grass pea intercropping system. RESULTS: The total yield and biomass net effect (NE) and the relative interaction index (RII) were significantly higher than 0 under all environmental conditions, demonstrating that plant-plant interactions generated positive effects in the intercropping system. The maize yield and biomass RII were 0.029-0.095 and 0.018-0.066, respectively, which indicated that maize growth was constantly facilitated. However, the RII for grass pea yield and biomass exhibited a different trend in comparison with maize. It was higher than 0 (as the facilitated species) under low soil P and moisture conditions and transitioned to values lower than 0 (facilitator species) under high P and moisture conditions, which showed that the type and intensity of plant-plant interactions steadily shifted with the applied stressors. Direct interactions decreased the maize rhizospheric soil pH by 1.5% and 1.9% under Low-P conditions. Notably, the rhizospheric soil acid and alkaline phosphatase secretions of maize and grass pea increased by 17.4-27.4% and 15.3-27.7%, respectively, in P-deficient soils. These results show that plant-plant interactions can effectively relieve P stress by mineralizing organophosphorus in P-deficient soils. Furthermore, the above tendency became more pronounced under drought-stressed conditions. The nylon barrier partially restricted the exchange and utilization of available nutrients and decreased the total yield and biomass by 1.8-7.8% and 1.1-7.8%, respectively. The presence of a solid barrier completely restricted interspecific rhizospheric interactions and decreased the total yield and biomass by 2.1-13.8% and 1.6-15.7%, respectively. Phytate and KH2PO4 addition intensified asymmetric interspecific competition, and grass pea was consistently subjected to competitive pressures. CONCLUSION: Briefly, the tradeoff between facilitation and competition was driven by rhizospheric interactions, and the transition in the intensity and type of interaction was highly dependent on resource availability in a biologically diverse system.


Asunto(s)
Fabaceae , Fósforo , Agricultura/métodos , Grano Comestible , Nylons , Suelo , Agua , Zea mays/fisiología
3.
Langmuir ; 37(46): 13696-13702, 2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34758614

RESUMEN

Adhesive and self-healing elastomers are urgently needed for their convenience and intelligence in biological medicine, flexible electronics, intelligent residential systems, etc. However, their inevitable use in harsh environments results in further enhancement requirements of the structure and performance of adhesive and self-healing elastomers. Herein, a novel self-healing and high-adhesion silicone elastomer was designed by the synergistic effect of multiple dynamic bonds. It revealed excellent stretchability (368%) and self-healing properties at room temperature (98.1%, 5 h) and in a water environment (96.4% for 5 h). Meanwhile, the resultant silicone elastomer exhibited high adhesion to metal and nonmetal and showed stable adhesion in harsh environments, such as under acidic (pH 1) and alkaline (pH 12) environments, salt water, petroleum ether, water, etc. Furthermore, it was applied as a shatter-proof protective layer and a rust-proof coating, proving its significant potential in intelligent residential system applications.


Asunto(s)
Elastómeros , Elastómeros de Silicona , Temperatura , Agua
4.
J Environ Manage ; 223: 306-313, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29935445

RESUMEN

The selective extraction and concentration of salt from coal gasification brine (CGB) by nanofiltration membranes is a promising technology to achieve near-zero liquid discharge of coal gasification wastewater. To investigate the feasibility of recovery of salts and the interaction of organic compounds, multivalent ions and monovalent ions on the rejection ratio, three nanofiltration membranes (OWNF1, NF270 and Desal-5 DK) with an 1812 spiral-wound module were used in crossflow filtration. The rejection mechanism was analyzed by comparing the rejection performance as a function of the operation pressure (increasing from 1.0 MPa to 2.5 MPa), the concentration (increasing from 10,000 mg/L to 25,000 mg/L) and pH values (increasing from 3.0 to 10.0). The concentrations of anions and cations were determined using an ion chromatographic analyzer and an inductively coupled plasma emission spectrometer, respectively. The results show that the rejection of sulfate and the chemical oxygen demand were higher than 92.12% and 78.84%, respectively, at appropriate operation, while negative rejection of chloride was observed in the CGB. The decreasing rejection of organic compounds was due to swelling of the membrane pore in high-concentration solutions. Meanwhile, the organic compounds weakened the negative charge of the membrane active layer, consequently decreasing the ion rejection. More than 85% of the sodium chloride could be recovered, indicating that this technology is suitable for resource recovery from CGB and near-zero liquid discharge of coal gasification industry.


Asunto(s)
Carbón Mineral , Purificación del Agua , Filtración , Membranas Artificiales , Nanotecnología , Sales (Química)
5.
World J Surg ; 40(9): 2237-44, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27393054

RESUMEN

BACKGROUND: Abdominal incision closure technique seriously influences patient prognosis. Most studies have focused on the different suture techniques and materials on midline incision, while little data are available in wide transverse or oblique incisions after liver resection (LR). The aim of the present study is to compare the two major incision suture methods after LR in our institute: Mass continuous suture (group P) and layered interrupted suture (group S). STUDY DESIGN: 258 patients undergoing LR with abdominal transverse or oblique incisions were prospectively enrolled. They were divided into two groups according to different abdominal incision suture methods and compared with the preoperative, intraoperative parameters, and postoperative wound complications. RESULTS: There were 118 patients in group P and 140 patients in group S, which was similar in general condition, primary disease, liver, and renal function. Incision length, total operation time, intraoperative blood loss, or perioperative antibiotics use were not different between the two groups. However, abdominal incision closure time and interval time for stitches removing after operation was significantly shorter in group P than group S (both p < 0.001). After a median follow-up of 16 months, the incidence of wound infection and fat liquefaction was more than two times higher in group S than group P, which, however, was not statistically different. Moreover, there was no difference in wound disruption or incisional hernia between the two groups. CONCLUSIONS: Although similar in occurrence of postoperative wound complications, mass continuous suture with polydioxanone seemed to be more timesaving in incision closure and motivated in wound healing.


Asunto(s)
Técnicas de Cierre de Herida Abdominal , Hepatectomía , Técnicas de Cierre de Herida Abdominal/efectos adversos , Pérdida de Sangre Quirúrgica , Femenino , Estudios de Seguimiento , Humanos , Hernia Incisional/etiología , Masculino , Persona de Mediana Edad , Tempo Operativo , Polidioxanona , Complicaciones Posoperatorias/etiología , Infección de la Herida Quirúrgica/etiología , Suturas , Cicatrización de Heridas
6.
J Comput Chem ; 36(3): 137-45, 2015 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-25363207

RESUMEN

Within the framework of the Förster theory, the electronic excitation energy transfer pathways in the cyanobacteria allophycocyanin (APC) trimer and hexamer were studied. The associated physical quantities (i.e., excitation energy, oscillator strength, and transition dipole moments) of the phycocyanobilins (PCBs) located in APC were calculated at time-dependent density functional theory (TDDFT) level of theory. To estimate the influence of protein environment on the preceding calculated physical quantities, the long-range interactions were approximately considered with the polarizable continuum model at the TDDFT level of theory, and the short-range interaction caused by surrounding aspartate residue of PCBs were taken into account as well. The shortest energy transfer time calculated in the framework of the Förster model at TDDFT/B3LYP/6-31+G* level of theory are about 0.10 ps in the APC trimer and about 170 ps in the APC monomer, which are in qualitative agreement with the experimental finding that a very fast lifetime of 0.43-0.44 ps in APC trimers, whereas its monomers lacked any corresponding lifetime. These results suggest that the lifetime of 0.43-0.44 ps in the APC trimers determined by Sharkov et al. was most likely attributed to the energy transfer of α(1) -84 ↔ ß(3) -84 (0.23 ps), ß(1) -84 ↔ α(2) -84 (0.11 ps) or ß(2) -84 ↔ α(3) -84 (0.10 ps). So far, no experimental or theoretical energy transfer rates between two APC trimmers were reported, our calculations predict that the predominate energy transfer pathway between APC trimers is likely to occur from α(3) -84 in one trimer to α(5) -84 in an adjacent trimer with a rate of 32.51 ps.


Asunto(s)
Biopolímeros/química , Cianobacterias/química , Transferencia Resonante de Energía de Fluorescencia , Ficocianina/química , Electrones , Modelos Moleculares
7.
Analyst ; 140(22): 7622-8, 2015 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-26421323

RESUMEN

A novel fluorescent resonant energy transfer (FRET) biosensor was fabricated for the detection of hepatitis B virus (HBV) DNA using poly(ethylenimine) (PEI) modified upconversion nanoparticles (NH2-UCNPs) as energy donor and gold nanoparticles (Au NPs) as acceptor. The PEI modified upconversion nanoparticles were prepared directly with a simple one-pot hydrothermal method, which provides high quality amino-group functionalized UCNPs with uniform morphology and strong upconversion luminescence. Two single-stranded DNA strands, which were partially complementary to each other, were then conjugated with NH2-UCNPs and Au NPs. When DNA conjugated NH2-UCNPs and Au NPs are mixed together, the hybridization between complementary DNA sequences on UCNPs and Au NPs will lead to the quenching of the upconversion luminescence due to the FRET process. Meanwhile, upon the addition of target DNA, Au NPs will leave the surface of the UCNPs and the upconversion luminescence can be restored because of the formation of the more stable double-stranded DNA on the UCNPs. The sensor we fabricated here for target DNA detection shows good sensitivity and high selectivity, which has the potential for clinical applications in the analysis of HBV and other DNA sequences.


Asunto(s)
ADN Viral/análisis , Oro/química , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/virología , Sustancias Luminiscentes/química , Nanopartículas/química , Polietileneimina/química , Secuencia de Bases , Transferencia Resonante de Energía de Fluorescencia/métodos , Hepatitis B/diagnóstico , Humanos , Nanopartículas/ultraestructura , Hibridación de Ácido Nucleico/métodos
8.
Appl Microbiol Biotechnol ; 99(3): 1249-59, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25117546

RESUMEN

A versatile method for the design of polydopamine-coated magnetic material with a brush-like structure used for Candida Rugosa lipase (CRL) immobilization was reported in this work. First, polydopamine (PDA) was coated on the surface of Fe3O4 nanospheres (Fe3O4 NPs) with a controllable thickness via dip coating process, and CRL can be immobilized on it directly via covalent bonding. Subsequently, PDA-functionalized Fe3O4 NPs were modified with dialdehyde polyethylene glycol (PEG) to obtain the aldehyde groups, and the brush-like structure of the magnetic supports was formed. After being characterized with various methods, it was verified that the prepared magnetic NPs possessed good monodispersity and displayed high saturation magnetization after modification. Meanwhile, the CRL was immobilized on it covalently, and the enzyme activities such as activity, stability, and reusability were investigated. Significantly, the versatility of polydopamine-inspired chemistry combined with the unique biological nature and tunability with dialdehyde PEG could evoke the efficiency of the CRL, making this a promising coating technique for various bio-applications.


Asunto(s)
Candida/enzimología , Enzimas Inmovilizadas/metabolismo , Indoles/síntesis química , Lipasa/metabolismo , Magnetismo , Nanosferas/química , Polímeros/síntesis química , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Compuestos Férricos/química , Lipasa/química
9.
J Ind Microbiol Biotechnol ; 42(5): 723-34, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25752766

RESUMEN

By the facile adhesion way, the novel composite complex by polydopamine (PDA) and magnetic graphite nanosheets (Fe3O4@GNSs) has been successfully synthesized. The resulting composite was characterized by means of scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectra, and Raman spectra, X-ray diffraction, X-ray photoelectron spectroscopy, and vibrating sample magnetometry. Meanwhile, the PDA functionalized Fe3O4@GNSs (Fe3O4@GNSs-PDA) was applied for Candida rugosa lipase (CRL) immobilization covalently without any toxic coupling agent. Combining the superior physical properties and chemical stability of Fe3O4@GNSs and the well biocompatibility, functional characteristics of PDA, the Fe3O4@GNSs-PDA composite displayed several advantages, including the high enzyme capacity, enzyme activity and stability and a decrease in enzyme loss. Our work demonstrated that the mussel-inspired Fe3O4@GNSs can be extended to many other applications such as biocatalytic, genetic and industrial.


Asunto(s)
Bivalvos , Candida/enzimología , Enzimas Inmovilizadas/metabolismo , Grafito/química , Lipasa/metabolismo , Fenómenos Magnéticos , Nanoestructuras/química , Adhesividad , Animales , Biomimética , Biotecnología , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Indoles/química , Lipasa/química , Magnetismo , Polímeros/química , Propiedades de Superficie
10.
Bioprocess Biosyst Eng ; 38(3): 429-35, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25214443

RESUMEN

A novel two-phase partitioning bioreactor (TPPB) modified by polysulfone (PSF) microspheres and immobilized enzyme (novozym-435) was formed, and the resulting TPPB was applied into mandelic acid chiral separation. The PSF microspheres containing n-hexanol (named PSF/hexanol microspheres) was prepared by using the phase inversion method, which was used as the organic phase. Meanwhile, the immobilized enzyme novozym-435 was used as a biocatalyst. The water phase was composed of the phosphate buffer solution (PBS). (R, S)-Methyl mandelate was selected as the substrate to study enzymatic properties. Different reaction factors have been researched, such as pH, reaction time, temperature and the quantity of biocatalyst and PSF/hexanol microspheres added in. Finally, (S)-mandelic acid was obtained with an 80 % optical purity after 24 h in the two-phase partitioning bioreactor. The enantiomeric excess (eep) values were very low in the water phase, in which the highest eep value was only 46 %. The eep of the two-phase partitioning bioreactor had been enhanced more obviously than that catalyzed in the water phase.


Asunto(s)
Reactores Biológicos , Enzimas Inmovilizadas/química , Lipasa/química , Ácidos Mandélicos/aislamiento & purificación , Microesferas , Polímeros , Sulfonas , Proteínas Fúngicas , Ácidos Mandélicos/química , Estereoisomerismo
11.
Biosens Bioelectron ; 259: 116417, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38795496

RESUMEN

Assembling functional molecules on the surface of an enzyme electrode is the most basic technique for constructing a biosensor. However, precise control of electron transfer interface or electron mediator on the electrode surface remains a challenge, which is a key step that affects the stability and sensitivity of enzyme-based biosensors. In this study, we propose the use of controllable free radical polymerization to grow stable 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) polymer as electron mediator on enzyme surface for the first time. Through scanning electron microscopy (SEM), Raman spectroscopy, electrode surface coverage measurement, static contact angle (SCA), and a series of electrochemical methods, it has been demonstrated that the TEMPO-based enzyme electrode exhibits a uniform hydrophilic morphology and stable electrochemical performance. Furthermore, the results show that the sensor demonstrates high sensitivity for detecting glucose biomolecules in artificial sweat and serum. Attributing to the quantitative and controllable radical polymerization of TEMPO redox assembled enzyme electrode surface, the as-proposed biosensor providing a use, storage, and inter-batch sensing stability, providing a vital platform for wearable/implantable biochemical sensors.


Asunto(s)
Técnicas Biosensibles , Óxidos N-Cíclicos , Electrodos , Enzimas Inmovilizadas , Oxidación-Reducción , Polimerizacion , Técnicas Biosensibles/métodos , Óxidos N-Cíclicos/química , Enzimas Inmovilizadas/química , Técnicas Electroquímicas/métodos , Glucosa/análisis , Glucosa/química , Glucosa Oxidasa/química , Humanos , Polímeros/química
12.
Nat Commun ; 15(1): 1587, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38383668

RESUMEN

The power of three-dimensional printing in designing personalized scaffolds with precise dimensions and properties is well-known. However, minimally invasive implantation of complex scaffolds is still challenging. Here, we develop amphiphilic dynamic thermoset polyurethanes catering for multi-material four-dimensional printing to fabricate supportive scaffolds with body temperature-triggered shape memory and water-triggered programmable deformation. Shape memory effect enables the two-dimensional printed pattern to be fixed into temporary one-dimensional shape, facilitating transcatheter delivery. Upon implantation, the body temperature triggers shape recovery of the one-dimensional shape to its original two-dimensional pattern. After swelling, the hydrated pattern undergoes programmable morphing into the desired three-dimensional structure because of swelling mismatch. The structure exhibits unusual soft-to-stiff transition due to the water-driven microphase separation formed between hydrophilic and hydrophobic chain segments. The integration of shape memory, programmable deformability, and swelling-stiffening properties makes the developed dynamic thermoset polyurethanes promising supportive void-filling scaffold materials for minimally invasive implantation.


Asunto(s)
Hidrogeles , Poliuretanos , Hidrogeles/química , Agua , Impresión Tridimensional
13.
Virol J ; 10: 215, 2013 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-23809248

RESUMEN

BACKGROUND: Enterovirus 71 (EV71) infections are associated with a high prevalence of hand, foot and mouth disease (HFMD) in children and occasionally cause lethal complications. Most infections are self-limiting. However, resulting complications, including aseptic meningitis, encephalitis, poliomyelitis-like acute flaccid paralysis, and neurological pulmonary edema or hemorrhage, are responsible for the lethal symptoms of EV71 infection, the pathogenesis of which remain to be clarified. RESULTS: In the present study, 2-week-old Institute of Cancer Research (ICR) mice were infected with a mouse-adapted EV71 strain. These infected mice demonstrated progressive paralysis and died within 12 days post infection (d.p.i.). EV71, which mainly replicates in skeletal muscle tissues, caused severe necrotizing myositis. Lesions in the central nervous system (CNS) and other tissues were not observed. CONCLUSIONS: Necrotizing myositis of respiratory-related muscles caused severe restrictive hypoventilation and subsequent hypoxia, which could explain the fatality of EV71-infected mice. This finding suggests that, in addition to CNS injury, necrotic myositis may also be responsible for the paralysis and death observed in EV71-infected mice.


Asunto(s)
Enterovirus Humano A/fisiología , Infecciones por Enterovirus/patología , Interacciones Huésped-Patógeno , Hipoventilación , Miositis/patología , Miositis/virología , Animales , Muerte , Modelos Animales de Enfermedad , Infecciones por Enterovirus/complicaciones , Infecciones por Enterovirus/virología , Hipoxia , Ratones Endogámicos ICR , Miositis/complicaciones , Parálisis
14.
Nat Nanotechnol ; 17(7): 777-787, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35551240

RESUMEN

Genome editing holds great potential for cancer treatment due to the ability to precisely inactivate or repair cancer-related genes. However, delivery of CRISPR/Cas to solid tumours for efficient cancer therapy remains challenging. Here we targeted tumour tissue mechanics via a multiplexed dendrimer lipid nanoparticle (LNP) approach involving co-delivery of focal adhesion kinase (FAK) siRNA, Cas9 mRNA and sgRNA (siFAK + CRISPR-LNPs) to enable tumour delivery and enhance gene-editing efficacy. We show that gene editing was enhanced >10-fold in tumour spheroids due to increased cellular uptake and tumour penetration of nanoparticles mediated by FAK-knockdown. siFAK + CRISPR-PD-L1-LNPs reduced extracellular matrix stiffness and efficiently disrupted PD-L1 expression by CRISPR/Cas gene editing, which significantly inhibited tumour growth and metastasis in four mouse models of cancer. Overall, we provide evidence that modulating the stiffness of tumour tissue can enhance gene editing in tumours, which offers a new strategy for synergistic LNPs and other nanoparticle systems to treat cancer using gene editing.


Asunto(s)
Edición Génica , Neoplasias , Animales , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Sistemas CRISPR-Cas/genética , Técnicas de Transferencia de Gen , Liposomas , Ratones , Nanopartículas , Neoplasias/genética , Neoplasias/terapia
15.
Orphanet J Rare Dis ; 15(1): 316, 2020 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-33176823

RESUMEN

BACKGROUND: Ameloblastic carcinoma (AC) is an odontogenic malignant tumor which is closely related to benign ameloblastoma. Because of its rarity, diagnosis and treatment are difficult. In this study, we summarized and analyzed the clinical and biological characteristics of AC. RESULTS: Fifteen patients with AC and a median age of 53 years were identified. Among of them, five patients who were tested carried a BRAF-V600E mutation. Two patients presented with cervical lymph nodes and lung metastases. Primary AC was more invasive, and the bone destruction ability of the primary type was more radical than that of the secondary type. CONCLUSIONS: This study revealed that the BRAF-V600E mutation was related to the aggressive behavior of AC, and early radical resection is crucial. Moreover, targeted therapy may be a new direction in the future.


Asunto(s)
Ameloblastoma , Carcinoma , Tumores Odontogénicos , Ameloblastoma/genética , Ameloblastoma/cirugía , Humanos , Persona de Mediana Edad
16.
Theranostics ; 10(2): 725-740, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31903147

RESUMEN

Chitin-derived hydrogels are commonly used in bone regeneration because of their high cell compatibility; however, their poor mechanical properties and little knowledge of the interaction between the materials and host cells have limited their practical application. Methods: To evaluate osteoinductivity and enhance the mechanical properties of a newly synthesized thermosensitive hydroxypropyl chitin hydrogel (HPCH), a mesenchymal stem cell (MSC)-encapsulated HPCH was infused into a three-dimensional-printed poly (ε-caprolactone) (PCL)/ nano-hydroxyapatite (nHA) scaffold to form a hybrid scaffold. The mechanical properties and cell compatibility of the scaffold were tested. The interaction between macrophages and scaffold for angiogenesis and osteogenesis were explored in vitro and in vivo. Results: The hybrid scaffold showed improved mechanical properties and high cell viability. When MSCs were encapsulated in HPCH, osteo-differentiation was promoted properly via endochondral ossification. The co-culture experiments showed that the hybrid scaffold facilitated growth factor secretion from macrophages, thus promoting vascularization and osteoinduction. The Transwell culture proved that MSCs modulated the inflammatory response of HPCH. Additionally, subcutaneous implantation of MSC-encapsulated HPCH confirmed M2 activation. In situ evaluation of calvarial defects confirmed that the repair was optimal in the MSC-loaded HPCH + PCL/nHA group. Conclusions: PCL/nHA + HPCH hybrid scaffolds effectively promoted vascularization and osteoinduction via osteogenesis promotion and immunomodulation, which suggests promising applications for bone regeneration.


Asunto(s)
Regeneración Ósea , Hidrogeles/química , Inmunomodulación , Células Madre Mesenquimatosas/citología , Neovascularización Fisiológica , Osteogénesis , Andamios del Tejido/química , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Adhesión Celular , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Quitina/química , Modelos Animales de Enfermedad , Durapatita/química , Masculino , Células Madre Mesenquimatosas/metabolismo , Poliésteres/química , Ratas , Ratas Sprague-Dawley , Temperatura , Ingeniería de Tejidos/métodos
17.
Environ Sci Pollut Res Int ; 26(21): 21655-21667, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31129894

RESUMEN

The purpose of this study is to investigate the enhancement of polycaprolactone (PCL) on total nitrogen (TN) removal of coal pyrolysis wastewater (CPW) with low COD to nitrogen ratio by partial nitrification-denitrification bioprocess (PNDB) in one single reactor. With the innovative combination of PCL and PNDB, the TN removal efficiency in the experimental reactor (signed as R1) was 10.21% higher than control reactor (R2). Nitrite accumulation percentage (NAP) in R1 was 82.02%, which was 17.49% higher than R2 at the dissolved oxygen (DO) concentration of 0.9-1.5 mg/L, for the reason that the extra DO was consumed by PCL biodegradation at the aerobic period. Gel permeation chromatography (GPC) results demonstrated that organics with the molecular weight of 185 Da, which could serve as additional carbon sources for denitrifiers, were generated during the PCL hydrolysis process at the anoxic period. PCL was hydrolyzed by extracellular enzymes with the break of the ester bond which was confirmed by FT-IR spectrometer. Microbial community analysis revealed that Ferruginibacter was the dominant hydrolysis bacteria in R1. Nitrosomonas were the main ammonium-oxidizing bacteria (AOB) and Hyphomicrobium were the denitrifiers in this study.


Asunto(s)
Carbón Mineral , Poliésteres/química , Eliminación de Residuos Líquidos/métodos , Compuestos de Amonio/metabolismo , Bacterias/metabolismo , Reactores Biológicos/microbiología , Carbono/metabolismo , Desnitrificación , Nitrificación , Nitritos/metabolismo , Nitrógeno/metabolismo , Pirólisis , Espectroscopía Infrarroja por Transformada de Fourier , Aguas Residuales/química
18.
Mater Sci Eng C Mater Biol Appl ; 101: 232-242, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31029316

RESUMEN

Polyetheretherketone (PEEK) has been used in orthopedic surgery for several decades. Numerous methods were invented to alter the properties of PEEK. By adding nanoparticles, fibers, etc., elastic modulus and strength of PEEK can be changed to meet certain demand. In this study, tantalum (Ta), a promising metal, was introduced to modify the properties of PEEK, in which PEEK was reinforced with different contents of tantalum nanoparticles (from 1 wt% to 9 wt%). Mechanical properties and biological functions (both in vitro and in vivo) were then investigated. The highest elastic modulus and compressive strength were observed in 3%Ta-PEEK. Cell experiments as cell adhesion, collagen secretion, biomineralization and osteogenesis related gene expression showed preferable results in 3%Ta-PEEK and 5%Ta-PEEK. Improved bone integration was shown in 3%Ta-PEEK and 5%Ta-PEEK in vivo. Above all, enhanced mechanical properties and promoted bone formation were proved for 3%Ta-PEEK and 5%Ta-PEEK compared to others groups both in vitro and in vivo, suggesting that the addition of tantalum nanoparticles modified the osseointegration ability of PEEK. This composite of tantalum and PEEK could have a clinical potential for orthopedic implants.


Asunto(s)
Cetonas/farmacología , Nanopartículas/química , Osteogénesis/efectos de los fármacos , Polietilenglicoles/farmacología , Tantalio/farmacología , Fosfatasa Alcalina/metabolismo , Animales , Benzofenonas , Rastreo Diferencial de Calorimetría , Adhesión Celular/efectos de los fármacos , Línea Celular , Colágeno/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Ensayo de Materiales , Ratones , Minerales/metabolismo , Nanopartículas/toxicidad , Oseointegración/efectos de los fármacos , Osteogénesis/genética , Polímeros , Ratas Sprague-Dawley , Espectrometría por Rayos X , Propiedades de Superficie , Termogravimetría
19.
Bioresour Technol ; 245(Pt A): 786-793, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28926910

RESUMEN

Three identical anoxic-aerobic membrane bioreactors (MBRs) were operated in parallel for 300 consecutive days for raw (R1), ozonated (R2) and catalytic ozonated (R3) biologically pretreated coal gasification wastewater (BPCGW) treatment. The results demonstrated that catalytic ozonation process (COP) applied asa pretreatment remarkably improved the performance of the unsatisfactory single MBR. The overall removal efficiencies of COD, NH3-N and TN in R3 were 92.7%, 95.6% and 80.6%, respectively. In addition, typical nitrogenous heterocyclic compounds (NHCs) of quinoline, pyridine and indole were completely removed in the integrated process. Moreover, COP could alter sludge properties and reshape microbial community structure, thus delaying the occurrence of membrane fouling. Finally, the total cost for this integrated process was estimated to be lower than that of single MBR. The results of this study suggest that COP is a good option to enhance pollutants removal and alleviate membrane fouling in the MBR for BPCGW treatment.


Asunto(s)
Reactores Biológicos , Carbón Mineral , Aguas Residuales , Compuestos Heterocíclicos , Membranas Artificiales , Ozono , Aguas del Alcantarillado
20.
ACS Nano ; 11(12): 12641-12649, 2017 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-29149552

RESUMEN

The discovery of biocompatible or bioactive nanoparticles for medicinal applications is an expensive and time-consuming process that may be significantly facilitated by incorporating more rational approaches combining both experimental and computational methods. However, it is currently hindered by two limitations: (1) the lack of high-quality comprehensive data for computational modeling and (2) the lack of an effective modeling method for the complex nanomaterial structures. In this study, we tackled both issues by first synthesizing a large library of nanoparticles and obtained comprehensive data on their characterizations and bioactivities. Meanwhile, we virtually simulated each individual nanoparticle in this library by calculating their nanostructural characteristics and built models that correlate their nanostructure diversity to the corresponding biological activities. The resulting models were then used to predict and design nanoparticles with desired bioactivities. The experimental testing results of the designed nanoparticles were consistent with the model predictions. These findings demonstrate that rational design approaches combining high-quality nanoparticle libraries, big experimental data sets, and intelligent computational models can significantly reduce the efforts and costs of nanomaterial discovery.


Asunto(s)
Materiales Biocompatibles/química , Oro/química , Modelos Químicos , Nanoestructuras/química , Línea Celular Tumoral , Células HEK293 , Hemo-Oxigenasa 1/química , Humanos , Relación Estructura-Actividad , Propiedades de Superficie
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