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1.
Small ; 20(25): e2309031, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38258399

RESUMEN

Liposomes are widely used in the biological field due to their good biocompatibility and surface modification properties. With the development of biochemistry and material science, many liposome structures and their surface functional components have been modified and optimized one by one, pushing the liposome platform from traditional to functionalized and intelligent, which will better satisfy and expand the needs of scientific research. However, a main limiting factor effecting the efficiency of liposomes is the complicated environmental conditions in the living body. Currently, in order to overcome the above problem, functionalized liposomes have become a very promising strategy. In this paper, binding strategies of liposomes with four main functional elements, namely nucleic acids, antibodies, peptides, and stimuli-responsive motif have been summarized for the first time. In addition, based on the construction characteristics of functionalized liposomes, such as drug-carrying, targeting, long-circulating, and stimulus-responsive properties, a comprehensive overview of their features and respective research progress are presented. Finally, the paper critically presents the limitations of these functionalized liposomes in the current applications and also prospectively suggests the future development directions, aiming to accelerate realization of their industrialization.


Asunto(s)
Liposomas , Liposomas/química , Humanos , Sistemas de Liberación de Medicamentos/métodos , Péptidos/química
2.
Eur Spine J ; 33(4): 1524-1532, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38315225

RESUMEN

PURPOSE: To report the incidence and risk factors of adjacent vertebral fracture (AVF) after percutaneous vertebroplasty (PVP) in patients with osteoporotic vertebral compression fractures (OVCFs). We focused to investigate effect of radiological or surgical features on AVF. METHODS: All patients with OVCFs who were treated with PVP between January 2016 and December 2019 were retrospectively reviewed. Patients were followed up at least 12 months after procedure according to treatment protocol. AVF was defined as postoperatively recurrent intractable back pain and subsequently presence of fracture on magnetic resonance imaging (MRI) in adjacent levels. Clinical, radiological, and surgical factors potentially affecting occurrence of AVF were recorded and analyzed using univariate and multivariate analysis. RESULTS: Totally, 1077 patients with 1077 fractured vertebrae who underwent PVP were enrolled in the study, after inclusion and exclusion criteria were met. Mean follow-up time was 24.3 ± 11.9 months (range, 12-59 months). AVF was identified in 98 (9.1%) patients. Univariate analysis showed that seven significant factors related to AVF were older age, non-traumatic fracture, cortical disruption on anterior wall, cortical disruption on lateral wall, basivertebral foramen, type-B leakage and type-C leakage. In multivariate analysis, two clinical factors, older age (P = 0.031) and non-traumatic fracture (P = 0.002), were significantly associated with AVF. However, any radiological or surgical factor did not reach significance in final model analysis. CONCLUSIONS: Incidence of AVF after PVP in patients with OVCFs was 9.1% (98/1077). Older age and non-traumatic fracture were two clinical risk factors for AVF. Neither radiological nor surgical feature was significantly correlated with AVF.


Asunto(s)
Fracturas por Compresión , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Vertebroplastia , Humanos , Vertebroplastia/efectos adversos , Vertebroplastia/métodos , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/cirugía , Estudios Retrospectivos , Fracturas por Compresión/diagnóstico por imagen , Fracturas por Compresión/epidemiología , Fracturas por Compresión/etiología , Factores de Riesgo , Cementos para Huesos/efectos adversos , Resultado del Tratamiento
3.
Chirality ; 34(1): 147-159, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34749430

RESUMEN

Chiral resolution of binaphthylamine is often a toilful conundrum in the field of analytical chemistry and biomedicine. The work puts forward a selective, sensitive, and miniaturized analytical method based on molecularly imprinted polymers (MIPs) as adsorbent for miniaturized tip solid-phase extraction (MTSPE) in the separation of binaphthylamine enantiomer. This method combines the advantages of MIPs (high selectivity), MTSPE (low consumption), and high-performance liquid chromatography (HPLC, high sensitivity). A simple synthesis methodology of MIP (P2) was conducted through bulk polymerization with (S)-(-)-1,1'-binaphthyl-2,2'-diamine (S-DABN) as template together with methacrylic acid monomer, and ethylene glycol dimethacrylate as cross-linker in proper porogen, realizing a selective recognition and efficient enrichment for S-DABN. The method exhibited appreciable linearity (0.06-1.00 mg ml-1 ), low quantification limit (0.056 mg ml-1 ), good absolute recoveries (45.70%-69.29%), and high precision (relative standard deviations ≤ 3.54%), along with low consumption (0.50 ml sample solution and 25.0 mg adsorbent). Based on the density functional theory, computational simulation was used to make a preliminary prediction for rational design of MIPs and gave a reasonable elaboration involving the potential mechanism of templates interacting with functional monomers. The adsorption kinetics and thermodynamics were investigated to evaluate the recombination process of substrates. In addition, the selectivity of MIPs for S-DABN was obtained by MIP-MTSPE coupled with HPLC, which supports the feasibility of this convenient design process. The proposed method was employed for selective extraction of S-DABN and exhibited promising potential in the application of chiral analysis.


Asunto(s)
Impresión Molecular , Polímeros , Adsorción , Cromatografía Líquida de Alta Presión , Diaminas , Naftalenos , Extracción en Fase Sólida , Estereoisomerismo
4.
BMC Musculoskelet Disord ; 22(1): 805, 2021 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-34537042

RESUMEN

BACKGROUND: The impact of intravertebral cleft (IVC) on cement leakage in percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCFs) has been discussed. However, the results were conflicting, as the study population and cement leakage classification were heterogeneous. The aim of the study was to evaluate the impact of IVC on the incidence of leakage through vein, leakage through cortex as well as general leakage in PVP for OVCFs. METHODS: All patients with OVCFs who underwent PVP between January 2016 and June 2019 at our institution were retrospectively reviewed. Patients were eligible for this case-control study if they were diagnosed as single level fracture in spine. After inclusive and exclusive criteria were met, a total of 139 patients with IVC were enrolled as the study group. Non-IVC controls were matched in a 1:1 ratio in age (within 3 years), sex and fracture severity with patients in study group. Cement leakage were classified into four types [type B (through basivertebral vein), type S (through segmental vein), type-C (through a cortical defect), and type D (intradiscal leakage)], furtherly into two types [venous type (type-B or/and type S) and cortical type (type-C or/and type-D)]. A general leakage rate and a specific leakage rate per each type were compared between both groups. RESULTS: Each group included 139 patients. Groups were homogenous for age, sex, fracture severity, fracture location, fracture type, cement volume, puncture approach and property of cement. Compared with control group, IVC group had a significantly lower rate of type-B (20.9% vs. 31.7%, P = 0.041), type-S (24.5% vs. 52.5%, P = 0.000), and venous type leakage (37.4% vs. 67.6%, P = 0.000), a significantly higher rate of type-C (25.9% vs. 12.2%, P = 0.004), type-D (16.5% vs. 6.5%, P = 0.009), and cortical type leakage (40.3% vs. 16.5%, P = 0.000), no significant difference on the rate of general leakage (67.6% vs. 76.3%, P = 0.109). CONCLUSION: IVC decreased the risk of cement leakage through vein and increased the risk of cement leakage through cortex. However, it had no significant effect on the occurrence of general leakage.


Asunto(s)
Fracturas por Compresión , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Vertebroplastia , Cementos para Huesos/uso terapéutico , Estudios de Casos y Controles , Preescolar , Fracturas por Compresión/diagnóstico por imagen , Fracturas por Compresión/epidemiología , Fracturas por Compresión/cirugía , Humanos , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/cirugía , Estudios Retrospectivos , Factores de Riesgo , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/cirugía , Resultado del Tratamiento , Vertebroplastia/efectos adversos
5.
Oral Dis ; 25(8): 1964-1971, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31397928

RESUMEN

OBJECTIVE: Epithelial-mesenchymal transition (EMT) is important in the tooth development and tumor invasion. We investigated the effect of interleukin-8 (IL-8) on the EMT process in primary-cultured ameloblastoma tumor cells (AM-P) and ameloblastoma immortalized tumor cells (AM-L) and its underlying mechanism. METHODS: IL-8 levels in ameloblastomas were detected by immunofluorescence staining and ELISA. AM-P cells and AM-L cells were stimulated with IL-8, and EMT transcription factors, total ß-catenin and phosphorylated-ß-catenin (p-ß-catenin) levels were determined by Western blot analysis and immunofluorescence staining. ß-catenin siRNA was used to knockdown ß-catenin expression in AM-P cells and AM-L cells stimulated with IL-8. RESULTS: IL-8 was highly expressed in the solid ameloblastomas. IL-8 promoted the EMT process in ameloblastoma tumor cells in vitro, as evidenced by decreased E-cadherin and increased vimentin, twist and zeb1 levels. IL-8 also increased total ß-catenin and p-ß-catenin expression in ameloblastoma tumor cells, and ß-catenin knockdown partially inhibited the EMT process in tumor cells, as evidenced by increased E-cadherin, and decreased vimentin and zeb1 levels. CONCLUSIONS: IL-8 could promote EMT in ameloblastoma tumor cells by activating ß-catenin and its downstream transcription factor zeb1.


Asunto(s)
Ameloblastoma/genética , Cadherinas/genética , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica/fisiología , Interleucina-8/metabolismo , beta Catenina/metabolismo , Ameloblastoma/metabolismo , Ameloblastoma/patología , Cadherinas/metabolismo , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/fisiología , Humanos , beta Catenina/genética
6.
Anal Bioanal Chem ; 408(20): 5567-76, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27255103

RESUMEN

An electrochemical sensor of acetaminophen based on poly(diallyldimethylammonium chloride) (PDDA)-functionalized reduced graphene-loaded Al2O3-Au nanoparticles coated onto glassy carbon electrode (Al2O3-Au/PDDA/reduced graphene oxide (rGO)/glass carbon electrode (GCE)) were prepared by layer self-assembly technique. The as-prepared electrode-modified materials were characterized by scanning electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy. The electrocatalytic performances of Al2O3-Au/PDDA/rGO-modified glassy carbon electrode toward the acetaminophen were investigated by cyclic voltammetry and differential pulse voltammetry. The modified electrodes of graphene oxide (GO)/GCE, PDDA/rGO/GCE, and Al2O3-Au/PDDA/rGO/GCE were constructed for comparison and learning the catalytic mechanism. The research showed Al2O3-Au/PDDA/rGO/GCE having good electrochemical performance, attributing to the synergetic effect that comes from the special nanocomposite structure and physicochemical properties of Al2O3-Au nanoparticles and graphene. A low detection limit of 6 nM (S/N = 3) and a wide linear detection range from 0.02 to 200 µM (R (2) = 0.9970) was obtained. The preparation of sensor was successfully applied for the detection of acetaminophen in commercial pharmaceutical pills. Graphical abstract Schematic diagram of synthesis of Al2O3-Au/PDDA/rGO/GCE.


Asunto(s)
Acetaminofén/análisis , Técnicas Biosensibles/instrumentación , Conductometría/instrumentación , Grafito/química , Nanopartículas del Metal/química , Polietilenos/química , Compuestos de Amonio Cuaternario/química , Acetaminofén/química , Óxido de Aluminio/química , Electrodos , Diseño de Equipo , Análisis de Falla de Equipo , Oro/química , Nanopartículas del Metal/ultraestructura , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
7.
Macromol Rapid Commun ; 35(13): 1198-203, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24715705

RESUMEN

Hydrozirconation on vinyl-terminated substrates (silicon wafer and nanosilica sphere) is employed as an efficient way for immobilization of zirconocene catalyst through Zr-C bonds, which is applied in surface coordination ethylene polymerization producing surface-tethered polyethylene (PE). The formation of Zr-C σ bond induced by hydrozirconation provides an initiator precursor for growing a layer of PE covalently linked onto substrates. The results from SEM, AFM, and TEM show that the surface polymerization is controlled by hydrozirconation. Surface pattern or core-shell structure with crystalline PE coating can be formed, when silicon wafer is selectively functionalized with vinyl-groups or vinyl-modified nanosilica is applied. It is believed that hydrozirconation for the synthesis of zirconocene initiator can be a versatile route to prepare polyolefin hybrid materials.


Asunto(s)
Compuestos Organometálicos/química , Polietileno/química , Catálisis , Polimerizacion , Propiedades de Superficie , Rayos Ultravioleta , Circonio/química
8.
Biol Trace Elem Res ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39331325

RESUMEN

Iron deficiency anemia (IDA) is a prevalent issue in pregnant women and children. However, the causal relationship between IDA in pregnancy and caries susceptivity in offspring remains unclear. This study aimed to explore the role of iron level during pregnancy on caries susceptivity of offsprings. Here, low-iron (LI) and high-iron (HI) models were established in maternal rats, and iron-related characteristics were examined in maternal rats and their offsprings. After induction of caries in rat offsprings, the carious lesions were evaluated by the Keyes scores, and microstructural damages in molars were observed by scanning electron microscopy. The results showed that LI in maternal rats induced IDA in rat offsprings, and HI only increased serum ferritin in offsprings. LI and HI in maternal rats had no effect on the morphological structure of salivary glands in rat offsprings. After inducing caries, rat offsprings in the LI group exhibited significant increase in enamel lesions at the smooth surface, and on enamel, slight dentinal, and moderate dentinal lesions at the sulcal surface. Only enamel lesions at the sulcal surface were significantly weakened in the HI group. Additionally, visible enamel damages were observed in the LI group. To sum up, iron deficiency during pregnancy enhances caries susceptibility in rat offsprings.

9.
Acta Biomater ; 181: 19-45, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38729548

RESUMEN

Zwitterionic polymers possess equal total positive and negative charges in the repeating units, making them electrically neutral overall. This unique property results in superhydrophilicity, which makes the zwitterionic polymers highly effective in resisting protein adsorption, thus endowing the drug carriers with long blood circulation time, inhibiting thrombus formation on biomedical devices in contact with blood, and ensuring the good sensitivity of sensors in biomedical application. Moreover, zwitterionic polymers have tumor-targeting ability and pH-responsiveness, rendering them ideal candidates for antitumor drug delivery. Additionally, the high ionic conductivity of zwitterionic polymers makes them an important raw material for ionic skin. Zwitterionic polymers exhibit remarkable resistance to bacterial adsorption and growth, proving their suitability in a wide range of biomedical applications such as ophthalmic applications, and wound dressings. In this paper, we provide an in-depth analysis of the different structures and characteristics of zwitterionic polymers and highlight their unique qualities and suitability for biomedical applications. Furthermore, we discuss the limitations and challenges that must be overcome to realize the full potential of zwitterionic polymers and present an optimistic perspective for zwitterionic polymers in the biomedical fields. STATEMENT OF SIGNIFICANCE: Zwitterionic polymers have a series of excellent properties such as super hydrophilicity, anti-protein adsorption, antibacterial ability and good ionic conductivity. However, biomedical applications of multifunctional zwitterionic polymers are still a major field to be explored. This review focuses on the design and application of zwitterionic polymers-based nanosystems for targeted and responsive delivery of antitumor drugs and cancer diagnostic agents. Moreover, the use of zwitterionic polymers in various biomedical applications such as biomedical devices in contact with blood, biosensors, ionic skin, ophthalmic applications and wound dressings is comprehensively described. We discuss current results and future challenges for a better understanding of multifunctional zwitterionic polymers for biomedical applications.


Asunto(s)
Polímeros , Polímeros/química , Humanos , Animales , Materiales Biocompatibles/química , Sistemas de Liberación de Medicamentos , Portadores de Fármacos/química
10.
Zhongguo Zhong Yao Za Zhi ; 38(7): 995-9, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23847944

RESUMEN

OBJECTIVE: To optimize the conditions of purifying the total alkaloids in Aconitum szechenyianum with macroporous adsorption resin, and compare the content of total alkaloids and aconitine in A. szechenyianum from different producing areas, in order to provide basis for further studies. METHOD: The orthogonal experiment method was adopted for optimizing the conditions of purifying the total alkaloids in A. szechenyianum with macroporous adsorption resin. The content of total alkaloids and aconitine were determined by using the titration method. The total alkaloids in A. szechenyianum from different producing areas were purified under optimum processing conditions. Aconitine was determined by HPLC. RESULT: Different processing conditions showed different influences on the purification of total alkaloids. The optimum conditions were resin type HPD-722, ethanol concentration of 80% , and ethanol elution volume of 80 mL x min(-1). The contents of aconitine in A. szechenyianum from different producing areas--Qinghai, Maxianshan, Ningxia and Yongdeng were 0.493 5, 0.883 5, 1.527 8, 1.664 4 mg x g(-1), respectively. CONCLUSION: The optimum processing conditions used in this essay could be used for purifying the total alkaloids and aconitine. A. szechenyianum from Yongdeng and Gansu contains the highest content of aconitine.


Asunto(s)
Aconitina/química , Aconitum/química , Alcaloides/química , Medicamentos Herbarios Chinos/química , Aconitina/aislamiento & purificación , Adsorción , Alcaloides/aislamiento & purificación , China , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/aislamiento & purificación , Porosidad , Resinas Sintéticas/química
11.
Front Bioeng Biotechnol ; 10: 804201, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35360406

RESUMEN

With the development of nanotechnology, nanomaterials have been used in dental fields over the past years. Among them, graphene and its derivatives have attracted great attentions, owing to their excellent physicochemical property, morphology, biocompatibility, multi-differentiation activity, and antimicrobial activity. In our review, we summarized the recent progress about their applications on the dentistry. The synthesis methods, structures, and properties of graphene-based materials are discussed. Then, the dental applications of graphene-based materials are emphatically collected and described. Finally, the challenges and outlooks of graphene-based nanomaterials on the dental applications are discussed in this paper, aiming at inspiring more excellent studies.

12.
Biotechnol Lett ; 31(8): 1159-65, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19343503

RESUMEN

Foot-and-mouth disease (FMD) and infectious bovine rhinotracheitis (IBR) are two important infectious diseases of cattle. Using bovine herpesvirus type 1 (BHV-1) as a gene delivery vector for development of live-viral vaccines has gained widespread interest. In this study, a recombinant BHV-1 was constructed by inserting the synthetic FMDV (O/China/99) VP1 gene in the the gE locus of BHV-1 genome under the control of immediately early gene promoter of human cytomegalovirus (phIE CMV) and bovine growth hormone polyadenylation (BGH polyA) signal. After homologous recombination and plaque purification, a recombinant virus named BHV-1/gE(-)/VP1 was acquired and identified. The immunogenicity was confirmed in a rabbit model by virus neutralization test and enzyme-linked immunosorbent assay (ELISA). The result indicated that the BHV-1/gE(-)/VP1 has the potential for being developed as a bivalent vaccine for FMD and IBR.


Asunto(s)
Proteínas de la Cápside/inmunología , Virus de la Fiebre Aftosa/inmunología , Fiebre Aftosa/prevención & control , Vectores Genéticos , Herpesvirus Bovino 1/inmunología , Vacunas Virales/inmunología , Animales , Anticuerpos Antivirales/sangre , Proteínas de la Cápside/genética , China , Ensayo de Inmunoadsorción Enzimática/métodos , Virus de la Fiebre Aftosa/genética , Herpesvirus Bovino 1/genética , Pruebas de Neutralización/métodos , Poliadenilación , Regiones Promotoras Genéticas , Conejos , Vacunas Virales/genética
13.
J Craniofac Surg ; 20(2): 558-60, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19305256

RESUMEN

Aspiration of a tooth in maxillofacial injuries is a known complication necessitating prompt recognition and early treatment to minimize potentially serious and, sometimes, even fatal consequences. Here, we report a rare and unusual case in its presentation, the patient having aspirated 2 permanent teeth after maxillofacial, cervical vertebrae, and thoracic region crush injuries due to a motor vehicle accident. The diagnosis of teeth aspiration was delayed until 2 weeks after the event. An aspirated anterior tooth was expectorated by the patient himself, and the other aspirated anterior tooth was removed by flexible bronchoscopy. The paper also emphasizes that clinicians must be aware of dental injury resulting from maxillofacial injuries and account for all teeth as part of their evaluation, keeping an open mind as to where a missing tooth might be located. A rapid diagnosis depends on high clinical suspicion, clinical signs, and radiologic findings.


Asunto(s)
Cuerpos Extraños/etiología , Incisivo , Traumatismos Maxilofaciales/complicaciones , Aspiración Respiratoria/etiología , Proceso Alveolar/lesiones , Broncoscopía , Vértebras Cervicales/lesiones , Diente Canino/lesiones , Humanos , Incisivo/lesiones , Masculino , Fracturas Maxilares/etiología , Traumatismos Torácicos/complicaciones , Avulsión de Diente/etiología , Fracturas de los Dientes/etiología , Adulto Joven
14.
Wei Sheng Wu Xue Bao ; 49(5): 677-82, 2009 May.
Artículo en Zh | MEDLINE | ID: mdl-19637579

RESUMEN

OBJECTIVE: In order to construct the recombinant bovine hepervirus-1 (BHV-1) which expressed foot and mouth disease virus (FMDV) VP1 gene, we constructed a BHV-1 gE gene transfer vector by inserting the synthetic VP1 gene of FMDV (O/China/99) under the immediate-early promoter of cytomegalovirus. METHODS: The mixtures of parental virus (BHV-1/gE(-)/LacZ+) DNA and transfer vector was transfected into bovine turbinate cells using calcium phosphate-mediated transfection. Then the propagated viruses were harvested. The recombinant BHV-1 (designated BHV-1/gE(-)/VP1) was obtained by selection for white virus plaques. RESULTS: PCR results showed that VP1 gene was successfully inserted into the genome of BHV-1/gE(-). The expression of VP1 in infected cells was proved by indirect immunofluorescence assay and Western blotting. CONCLUSION: The research provided a basis for development of BHV-1 vector vaccines for FMD and other important bovine infectious diseases.


Asunto(s)
Proteínas de la Cápside/metabolismo , Fiebre Aftosa/virología , Herpesvirus Bovino 1/metabolismo , Proteínas Recombinantes de Fusión/genética , Vacunas Virales/genética , Animales , Anticuerpos Antivirales/genética , Western Blotting , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Bovinos , Células Cultivadas , Clonación Molecular , Citomegalovirus/genética , Expresión Génica , Vectores Genéticos , Herpesvirus Bovino 1/genética , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/metabolismo , Porcinos
15.
Int J Biol Macromol ; 107(Pt A): 957-964, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28939516

RESUMEN

Magnetic hydroxyethyl cellulose/ionic liquid (MHEC/IL) materials were fabricated through a facile and fast process and their application as excellent adsorbents for hydroquinone was also demonstrated. The thermal stability, chemical structure and magnetic property of the MHEC/IL were characterized by the Scanning electron microscope (SEM), Transmission Electron Microscope (TEM), Fourier transform infrared spectrometer (FT-IR) and X-ray diffraction (XRD), respectively. The adsorbents were used for the removal of hydroquinone from simulated wastewater with a fast solid-liquid separation in the presence of external magnetic field. The influence of various analytical parameters on the adsorption of hydroquinone such as pH, contact time and initial ion concentration were studied in detail. The results showed that the maximum adsorption capacity was 335.68mgg-1, observed at pH 5 and temperature 30°C. Equilibrium adsorption was achieved within 30min. The kinetic data, obtained at the optimum pH 5, could be fitted with a pseudo-second order equation. Adsorption process could be well described by Freundlich adsorption isotherms. The obtained results indicated that the impregnation of the room temperature IL significantly enhances the removal efficiency of hydroquinone. The MHEC/IL may be suitable materials in phenols pollution cleanup if they are synthesized in largescale and at low price in near future.


Asunto(s)
Celulosa/análogos & derivados , Hidroquinonas/aislamiento & purificación , Líquidos Iónicos/química , Aguas Residuales/química , Adsorción , Celulosa/química , Quitosano/química , Concentración de Iones de Hidrógeno , Hidroquinonas/química , Hidroquinonas/toxicidad , Magnetismo , Fenoles/química , Fenoles/toxicidad , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Aguas Residuales/toxicidad , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidad , Difracción de Rayos X
16.
Anal Chim Acta ; 970: 82-90, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28433062

RESUMEN

An ion-exchange method to separate charged biomolecules on ultrathin layer chromatographic (UTLC) plates using electrospun Nafion-Polyacrylonitrile (PAN) nanofibers as the stationary phase is described. Sulfonate groups on Nafion provide the ion-exchange sites. The addition of PAN (a higher molecular weight polymer than Nafion) was used to facilitate the nanofiber formation process using electrospinning. Electrospinning parameters and separation conditions were optimized using fractional factorial design and response surface methodology. Nafion-PAN nanofibers containing 45% (w/w) Nafion with 0.407 mmol/g of SO3H group and 16.0 mmol/g of fluorine as an ion exchange stationary phase for UTLC were evaluated using the separations of amino acids and proteins, followed by visualizations using ninhydrin and fluorescamine, respectively. The electrospun Nafion-PAN plates showed high chemical stability under various mobile phase conditions. Mobile phase velocity decreased with the addition of Nafion into the electrospinning solutions. The sources of band broadening of analyte spots were investigated. The separation of amino acids showed high selectivity and separation efficiency. The separation of four proteins demonstrated the feasibility of Nafion-PAN UTLC for separating large biomolecules.


Asunto(s)
Resinas Acrílicas , Cromatografía en Capa Delgada , Polímeros de Fluorocarbono , Intercambio Iónico , Nanofibras , Proteínas/aislamiento & purificación
17.
Clin Implant Dent Relat Res ; 19(6): 1074-1081, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29052336

RESUMEN

BACKGROUND: There is no data available on the long-term outcomes of a rooted, platform-switched, microthreaded implant with a sandblasted, large-grid, and acid-etched surface. PURPOSE: This prospective, longitudinal study evaluated the clinical and radiographic outcomes of rooted, platform-switched, microthreaded and sandblasted, large-grid, and acid-etched (SLA) surface implants for 5 years. MATERIALS AND METHODS: Sixty implants were placed in sixty patients with partially edentulous maxillae or mandibles. The permanent prostheses were inserted 2-4 months after implant placement. Clinical and radiographic examinations were performed at follow-up visits scheduled postoperation, prosthesis installation, 1 year, and 5 years after surgery, to assess implant survival and success rates, biological and mechanical complications, and marginal bone loss. RESULTS: After 5 years' follow-up, four patients withdrawn from the study, and 56 implants achieved a 100% survival rate and 98.2% success rate. Three prosthetic complications occurred, resulting in a success rate for prostheses of 94.6%. The incidence of peri-implant mucositis was 9.1% and no peri-implantitis was diagnosed. The average marginal bone loss at the mesial aspect was 0.46 ± 0.27 mm after 1 year and 0.48 ± 0.27 mm after 5 years. The average marginal bone loss at the distal aspect was 0.46 ± 0.32 mm after 1 year and 0.50 ± 0.35 mm after 5 years. CONCLUSION: After 5 years of loading, the rooted, platform-switched, microthreaded, and SLA surface implants showed high survival and success rates, steady crestal bone levels, and excellent long-term clinical outcomes in the soft tissue. Overloading may be related to the marginal bone loss around implants, but the surgical protocol, different sites, and jaw position did not correlate with crestal bone loss.


Asunto(s)
Implantes Dentales , Diseño de Prótesis Dental , Adulto , Anciano , Pérdida de Hueso Alveolar/diagnóstico por imagen , Proceso Alveolar/diagnóstico por imagen , Implantación Dental Endoósea , Femenino , Humanos , Maxilares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Estudios Prospectivos , Radiografía Dental , Propiedades de Superficie
18.
Int J Biol Macromol ; 99: 578-585, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28283454

RESUMEN

A simple chemical bonding method to synthesize magnetic cellulose-poly(dopamine) (Fe3O4@CMC@PDA) was reported. The adsorption behaviors of resorcinol in aqueous solution on Fe3O4@CMC@PDA were systematically investigated. As the results shown that, with the advantage of high surface area, abundant hydroxyl and amino groups of Fe3O4@CMC@PDA, and the magnetic property of Fe3O4, the resorcinol can be easily and rapidly extracted from the water by magnetic attraction under investigation. The adsorption equilibrium of Fe3O4@CMC@PDA for resorcinol corresponded with Freundlich isotherm, and the novel adsorbent exhibited better resorcinol removal efficiency in solutions with low pH. It was found that the resorcinol adsorption performance of Fe3O4@CMC@PDA strongly depends on their surface charge concentration and specific surface area. These results provide evidences for estimating and optimizing the removal of phenols from the wastewater by using of Fe3O4@CMC@PDA composites in the future.


Asunto(s)
Celulosa/química , Indoles/química , Imanes/química , Polímeros/química , Resorcinoles/química , Resorcinoles/aislamiento & purificación , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Compuestos Férricos/química , Concentración de Iones de Hidrógeno , Cinética , Modelos Moleculares , Conformación Molecular , Termodinámica , Aguas Residuales/química
19.
Artículo en Inglés | MEDLINE | ID: mdl-28147299

RESUMEN

In this work, a chemiluminescence (CL) biosensor was prepared for ultrasensitive determination of deoxyribonucleic acid (DNA) based on the adsorption recognition function between core-shell Fe3O4@SiO2 - graphene oxide (Fe3O4@SiO2@GO) polymers and DNA. The Fe3O4@SiO2@GO polymers were composed by GO and magnetite nanoparticles. And the core-shell polymers were confirmed by Scanning Electron Microscope (SEM), X-Ray Powder Diffraction (XRD) and Fourier Transform Infrared (FTIR). Then Fe3O4@SiO2@GO was modified by DNA. Based on the principle of complementary base, Fe3O4@SiO2@GO-DNA was introduced to the CL system and the selectivity, sensitivity of DNA detection was significantly improved. The adsorption properties of Fe3O4@SiO2@GO to DNA were researched through the adsorption equilibrium, adsorption kinetic and thermodynamics. Under optimized CL conditions, DNA could be assayed with the linear concentration range of 5.0×10-12-2.5×10-11mol/L. The detection limit was 1.7×10-12mol/L (3δ) and the relative standard deviation (RSD) was 3.1%. The biosensor was finally used for the determination of DNA in laboratory samples and recoveries ranged from 99% to 103%. The satisfactory results revealed the potential application of Fe3O4@SiO2@GO-DNA-CL biosensor in the diagnosis and the treatment of human genetic diseases.


Asunto(s)
Técnicas Biosensibles/métodos , ADN/análisis , Compuestos Férricos/química , Grafito/química , Mediciones Luminiscentes/métodos , Polímeros/química , Dióxido de Silicio/química , Adsorción , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
20.
Mater Sci Eng C Mater Biol Appl ; 53: 23-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26042686

RESUMEN

Oxidation of diamond during the manufacturing of vitrified dental grinding tools would reduce the strength and sharpness of tools. Zinc oxide (ZnO) coating was deposited on diamond particles by urea precipitation method to protect diamond in borosilicate glass. The FESEM results showed that the ZnO coating was formed by plate-shaped particles. According to the TG results, the onset oxidation temperature of the ZnO-coated diamond was about 70 °C higher than the pristine diamond. The EDS results showed that ZnO diffused into the borosilicate glass during sintering. As the result, the bending strength of the composites containing ZnO-coated diamond was increased by 24% compared to that of the composites containing pristine diamond.


Asunto(s)
Instrumentos Dentales , Diamante/química , Urea/química , Óxido de Zinc/química , Ensayo de Materiales , Oxidación-Reducción
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