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1.
J Sep Sci ; 46(10): e2200711, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36929049

RESUMEN

An open tubular capillary electrochromatography column covalently bonded with polystyrene sulfonate was prepared via in situ polymerization using functionalized Azo-initiator 4,4'-Azobis(4-cyanopentanoyl chloride). Scanning electron, fluorescence, and atomic force microscopy techniques showed the formation of a relatively rough layer of polymer. In addition, -CN and C = O stretching vibrations from infrared spectroscopy proved the successful immobilization of the azo-initiator through covalent bonding and X-ray photoelectron spectroscopy confirmed the elemental composition of the formed polymer layer. The prepared column was found to be appropriate for small and medium-sized molecules separation. Compared to bare fused silica capillary column higher selectivity and resolution were obtained for the separation of alkaloids, sulfonamides, and peptides as a result of the electrostatic and pi-pi stacking interactions between the small organic molecules and the coated column without compromising the electroosmotic flow mobility. Separation efficiency was also increased compared to the bare capillary for the separation of alkaloids (about 1.5 times). Moreover, intraday, inter-day, intra-batch, and inter-batch relative standard deviation values of retention time and peak area of peptides were within 2% and 10%, respectively, indicating good repeatability of the column preparation procedure. The developed method for the covalent bonding of polymers through a functionalized azo-initiator could represent a promising stable method for the preparation of an open tubular column.


Asunto(s)
Alcaloides , Electrocromatografía Capilar , Cloruros , Sulfonamidas , Polimerizacion , Polímeros/química , Péptidos , Electrocromatografía Capilar/métodos
2.
J Environ Manage ; 335: 117531, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36857891

RESUMEN

Here, to prevent the corrosion of Q235 steel in the pickling and discover novel green corrosion inhibitors, the corrosion inhibition performance and eco-toxicity of cinchonain IIa were evaluated. Electrochemical experiments confirms that 200 mg/L cinchonain IIa reveals good corrosion inhibition performance with 94.08% on Q235 steel in HCl for 48 h. Scanning electron microscope (SEM) and atomic force microscope (AFM) observations suggest that cinchonain IIa can be firmly attached to the metal surface by forming a barrier film. The X-ray photoelectron spectroscopy (XPS) results further verify the bonding interaction between the functional groups and the steel matrix, and indicate the existence of protective film on the steel. Meanwhile, the inhibition mechanism at the molecular/atomic level is revealed through molecular dynamics simulation. Additionally, acute toxicity test shows that cinchonain IIa is a low toxic corrosion inhibitor. Moreover, the antioxidant enzyme activity experiments confirm that cinchonain IIa discloses no obvious damage to the antioxidant system of zebrafish. Overall, cinchonain IIa exhibits low potential risks to the healthy development of aquatic organisms and ecosystems. As a proven green and low toxic corrosion inhibitor, cinchonain IIa has a sustainable application in the anti-corrosion industry.


Asunto(s)
Cinchona , Contaminantes Químicos del Agua , Animales , Antioxidantes/metabolismo , Cinchona/toxicidad , Ecosistema , Acero/química , Pez Cebra , Contaminantes Químicos del Agua/toxicidad , Ecotoxicología
3.
Environ Sci Technol ; 56(4): 2181-2190, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35076226

RESUMEN

Since the 1960s, many indoor and outdoor smog chambers have been developed worldwide. However, most of them are made of Teflon films, which have relatively high background contaminations due to the wall effect. We developed the world's first medium-size quartz chamber (10 m3), which is jointed with 32 pieces of 5 mm thick polished quartz glasses and a stainless-steel frame. Characterizations show that this chamber exhibits excellent performance in terms of relative humidity (RH) (2-80%) and temperature (15-30 ± 1 °C) control, mixing efficiency of the reactants (6-8 min), light transmittance (>90% above 290 nm), and wall loss of pollutants. The wall loss rates of the gas-phase pollutants are on the order of 10-4 min-1 at 298 K under dry conditions. It is 0.08 h-1 for 100-500 nm particles, significantly lower than those of Teflon chambers. The photolysis rate of NO2 (JNO2) is automatically adjustable to simulate the diurnal variation of solar irradiation from 0 to 0.40 min-1. The inner surface of the chamber can be repeatedly washed with deionized water, resulting in low background contaminations. Both experiments (toluene-NOx and α-pinene-ozone systems) and box model demonstrate that this new quartz chamber can provide high-quality data for investigating SOA and O3 formation in the atmosphere.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Ozono/análisis , Politetrafluoroetileno , Cuarzo , Esmog/análisis
4.
Environ Res ; 215(Pt 2): 114376, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36165857

RESUMEN

Traditional corrosion inhibitors make great contribution to metal protection, but also cause environmental pollution. To solve the problem, plant extracts as green corrosion inhibitors have attracted much attention in recent years. Plants are good raw materials for corrosion inhibitors and also meet the requirements of industry. However, they have not been successfully applied in industry due to the unknown composition of the effective corrosion inhibitors and large dosage thereof. Therefore, cinchonain IIa was separated from Uncaria laevigata with abundant sources and low cost from nature in this work. Here we hypothesized that cinchonain IIa could show good corrosion inhibition performance for Q235 steel in the acidic medium. Through experiments and theoretical calculation, we studied the corrosion inhibition effect of cinchonain IIa on Q235 in 1 M HCl solution at 298 K for 48 h. Electrochemical experiments revealed that the inhibition efficiency of 200 mg/L cinchonain IIa in 1 M HCl for Q235 steel was 94.08% for 48 h. It even showed over 93% corrosion inhibition efficiency and durable protection performance to 28 d. Surface observations indicated that cinchonain IIa were firmly attached to the steel surface by forming a protective film. Moreover, quantum chemical calculation and molecular dynamics simulation revealed the inhibition mechanism at molecular and atomic level. Compared with some plant extracts, here we demonstrate that the outstanding advantages of cinchonain IIa include sustained protective effect, small dosage, and low toxicity. Accordingly, it may be used as a green industrial corrosion inhibitor with great potential in oilfield acidification and acid pickling.


Asunto(s)
Cáusticos , Uncaria , Corrosión , Extractos Vegetales , Acero/química
5.
J Sep Sci ; 45(14): 2621-2631, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35526264

RESUMEN

Recently, pharmaceuticals and personal care products in the water environment exhibited potential risks to both human and aquatic organisms. In order to improve the sensitivity and accuracy of pharmaceutical detection, the polyimidazolyl acetate ionic liquid was synthesized by Radziszewski reaction and coated on cellulose filter papers as a thin-film extraction phase for extraction of non-steroidal anti-inflammatory drugs from water. The attenuated total reflection-infrared spectrometry, thermogravimetric analysis, and scanning electron microscope analyses demonstrated that the polyimidazolyl acetate ionic liquid was successfully prepared and attached to the surface of the cellulose filter paper through chemical bonding. The adsorption capacity of the homemade thin-film extraction material for the four non-steroidal anti-inflammatory drugs was greater than 8898 ng/cm2 under the optimum conditions, and the desorption rate was over 90%. Then, a paper-based thin-film extraction phase-high-performance liquid chromatography-tandem mass spectrometry method was established for the extraction of non-steroidal anti-inflammatory drugs in water. This method provided limits of detection and limits of quantification were in the range of 0.02-0.15 and 0.17-0.50 µg/L, respectively. Hence, the obtained thin-film extraction phase showed excellent recovery and reproducibility for the target non-steroidal anti-inflammatory drugs with carboxyl groups from water.


Asunto(s)
Líquidos Iónicos , Contaminantes Químicos del Agua , Acetatos , Antiinflamatorios no Esteroideos/análisis , Celulosa , Cromatografía Líquida de Alta Presión , Humanos , Líquidos Iónicos/análisis , Límite de Detección , Reproducibilidad de los Resultados , Extracción en Fase Sólida/métodos , Agua/química , Contaminantes Químicos del Agua/análisis
6.
Molecules ; 27(19)2022 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-36234963

RESUMEN

Theranostics play an important role in cancer treatment due to its realized real-time tracking of therapeutic efficacy in situ. In this work, we have designed and synthesized a terpyridine-modified pillar [5]arenes (TP5). By the coordination of terpyridine and Zn2+, the complex TP5/Zn was obtained. Then, supramolecular amphiphile can be constructed by using host-guest complexation between a polyethylene glycol contained guest (PM) and TP5/Zn. Combining the fluorescence properties from the terpyridine group and the amphiphilicity from the system, the obtained TP5/Zn/PM can further be self-assembled into fluorescent particles with diameters of about 150 nm in water. The obtained particles can effectively load anti-cancer drugs and realize living cell imaging and a precise release of the drugs.


Asunto(s)
Antineoplásicos , Neoplasias , Antineoplásicos/farmacología , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Polietilenglicoles , Agua
7.
Planta ; 253(5): 90, 2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33818691

RESUMEN

MAIN CONCLUSION: CcBLH6 is a bell-like homeodomain-containing transcription factor that plays an important role of lignin biosynthesis in the control of fruit lignification pattern in Camellia chekiangoleosa. The fruit of Camellia chekiangoleosa has a unique lignification pattern that features with a thick pericarp containing a low level of lignification. Yet the fruit lignification pattern and the regulatory network of responsible gene transcription are poorly understood. Here, we characterized a bell-like homeodomain-containing (BLH) transcription factor from C. chekiangoleosa, CcBLH6, in the control of fruit lignification. CcBLH6 expression was highly correlated with the unique lignification pattern during fruit development. The ectopic expression of CcBLH6 promoted the lignification process of stem and root in Arabidopsis. We found that expression of genes related to lignin biosynthesis and its transcriptional regulation was altered in transgenic lines. In a Camellia callus-transformation system, overexpression of CcBLH6 greatly enhanced the expression of genes related to lignin biosynthesis and its transcriptional regulation was altered in transgenic lines. In the callus-transformation system, overexpression of CcBLH6 greatly enhanced the lignification of parenchymal cells, and the regulation of several genes involved in lignin accumulation was largely consistent between Arabidopsis and Camellia. Our study reveals a positive role of CcBLH6 in the regulation of lignin biosynthesis during fruit lignification in Camellia.


Asunto(s)
Camellia/genética , Camellia/metabolismo , Frutas/genética , Frutas/metabolismo , Proteínas de Homeodominio/metabolismo , Lignina/metabolismo , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas
8.
BMC Gastroenterol ; 17(1): 107, 2017 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-29041918

RESUMEN

BACKGROUND: None of current diagnostic methods has been proven to be a reliable tool for gastro-esophageal reflux disease (GERD). Pepsin in saliva has been proposed as a promising diagnostic biomarker for gastro-esophageal reflux. We aimed to determine the diagnostic value of salivary pepsin detection for GERD. METHODS: Two hundred and fifty patients with symptoms suggestive of GERD and 35 asymptomatic healthy volunteers provided saliva on morning waking, after lunch and dinner for pepsin determination using the Peptest lateral flow device. All patients underwent 24-h multichannel intraluminal impedance pH (24-h MII-pH) monitoring and upper gastrointestinal endoscopy. Based on 24-h MII-pH and endoscopy study, patients were defined as GERD (abnormal MII-pH results and/or reflux esophagitis) and non-GERD otherwise. RESULTS: Patients with GERD had a higher prevalence of pepsin in saliva and higher pepsin concentration than patients with non-GERD and healthy controls (P < 0.001 for all). The pepsin test had a sensitivity of 73% and a specificity of 88.3% for diagnosing GERD using the optimal cut-off value of 76 ng/mL. Postprandial saliva samples collected when the symptoms occurred had a more powerful ability to identify GERD. CONCLUSIONS: Salivary pepsin test had moderate diagnostic value for GERD. It may be a promising tool to replace the use of currently invasive tools with advantages of non-invasive, easy to perform and cost effective. TRIAL REGISTRATION: ChiCTR-DDD-16009506 (date of registration: October 20, 2016).


Asunto(s)
Reflujo Gastroesofágico/diagnóstico , Pepsina A/análisis , Saliva/química , Adulto , Anciano , Biomarcadores/análisis , China , Diagnóstico Diferencial , Endoscopía Gastrointestinal , Monitorización del pH Esofágico , Femenino , Humanos , Masculino , Manometría , Persona de Mediana Edad , Periodo Posprandial , Estudios Prospectivos , Sensibilidad y Especificidad
9.
J Mater Sci Mater Med ; 26(1): 5360, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25596860

RESUMEN

The study aims to investigate the techniques of design and construction of CT 3D reconstructional data-based polycaprolactone (PCL)-hydroxyapatite (HA) scaffold. Femoral and lumbar spinal specimens of eight male New Zealand white rabbits were performed CT and laser scanning data-based 3D printing scaffold processing using PCL-HA powder. Each group was performed eight scaffolds. The CAD-based 3D printed porous cylindrical stents were 16 piece × 3 groups, including the orthogonal scaffold, the Pozi-hole scaffold and the triangular hole scaffold. The gross forms, fiber scaffold diameters and porosities of the scaffolds were measured, and the mechanical testing was performed towards eight pieces of the three kinds of cylindrical scaffolds, respectively. The loading force, deformation, maximum-affordable pressure and deformation value were recorded. The pore-connection rate of each scaffold was 100 % within each group, there was no significant difference in the gross parameters and micro-structural parameters of each scaffold when compared with the design values (P > 0.05). There was no significant difference in the loading force, deformation and deformation value under the maximum-affordable pressure of the three different cylinder scaffolds when the load was above 320 N. The combination of CT and CAD reverse technology could accomplish the design and manufacturing of complex bone tissue engineering scaffolds, with no significant difference in the impacts of the microstructures towards the physical properties of different porous scaffolds under large load.


Asunto(s)
Huesos/patología , Durapatita/química , Poliésteres/química , Andamios del Tejido/química , Animales , Sustitutos de Huesos , Fémur/diagnóstico por imagen , Fémur/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Porosidad , Impresión Tridimensional , Conejos , Radiografía , Estrés Mecánico , Ingeniería de Tejidos/métodos
10.
Int J Biol Macromol ; 269(Pt 2): 132177, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38729484

RESUMEN

Tumor vaccine, which can effectively prevent tumor recurrence and metastasis, is a promising tool in tumor immunotherapy. However, heterogeneity of tumors and the inability to achieve a cascade effect limit the therapeutic effects of most developing tumor vaccine. We have developed a cascading immunoinducible in-situ mannose-functionalized polydopamine loaded with imiquimod phenylboronic hyaluronic acid nanocomposite gel vaccine (M/P-PDA@IQ PHA) through a boronic ester-based reaction. This reaction utilizes mannose-functionalized polydopamine loaded with imiquimod (M/P-PDA@IQ NAs) as a cross-linking agent to react with phenylboronic-grafted hyaluronic acid. Under near-infrared light irradiation, the M/P-PDA@IQ PHA caused local hyperthermia to trigger immunogenic cell death of tumor cells and tumor-associated antigens (TAAs) releasing. Subsequently, the M/P-PDA@IQ NAs which were gradually released by the pH/ROS/GSH-triggered degradation of M/P-PDA@IQ PHA, could capture and deliver these TAAs to lymph nodes. Finally, the M/P-PDA@IQ NAs facilitated maturation and cross-presentation of dendritic cells, as well as activation of cytotoxic T lymphocytes. Overall, the M/P-PDA@IQ PHA could serve as a novel in situ vaccine to stimulate several key nodes including TAAs release and capture, targeting lymph nodes and enhanced dendritic cells uptake and maturation as well as T cells activation. This cascading immune activation strategy can effectively elicit antitumor immune response.


Asunto(s)
Vacunas contra el Cáncer , Ácido Hialurónico , Hidrogeles , Indoles , Nanopartículas , Polímeros , Ácido Hialurónico/química , Polímeros/química , Vacunas contra el Cáncer/química , Vacunas contra el Cáncer/inmunología , Indoles/química , Indoles/farmacología , Animales , Ratones , Hidrogeles/química , Nanopartículas/química , Humanos , Imiquimod/química , Imiquimod/farmacología , Células Dendríticas/inmunología , Vacunación , Línea Celular Tumoral , Inmunoterapia/métodos , Reactivos de Enlaces Cruzados/química , Neoplasias/inmunología , Neoplasias/terapia , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/efectos de los fármacos
11.
Biomolecules ; 13(6)2023 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-37371591

RESUMEN

In this nano era, nanomaterials and nanostructures are popular in developing novel functional materials. However, the combinations of materials at micro and macro scales can open new routes for developing novel trans-scale products with improved or even new functional performances. In this work, a brand-new hybrid, containing both nanofibers and microparticles, was fabricated using a sequential electrohydrodynamic atomization (EHDA) process. Firstly, the microparticles loaded with drug (berberine hydrochloride, BH) molecules in the cellulose acetate (CA) were fabricated using a solution electrospraying process. Later, these microparticles were suspended into a co-dissolved solution that contained BH and a hydrophilic polymer (polypyrrolidone, PVP) and were co-electrospun into the nanofiber/microparticle hybrids. The EHDA processes were recorded, and the resultant trans-scale products showed a typical hybrid topography, with microparticles distributed all over the nanofibers, which was demonstrated by SEM assessments. FTIR and XRD demonstrated that the components within the hybrids were presented in an amorphous state and had fine compatibility with each other. In vitro dissolution tests verified that the hybrids were able to provide the designed dual-step drug release profiles, a combination of the fast release step of BH from the hydrophilic PVP nanofibers through an erosion mechanism and the sustained release step of BH from the insoluble CA microparticles via a typical Fickian diffusion mechanism. The present protocols pave a new way for developing trans-scale functional materials.


Asunto(s)
Berberina , Nanofibras , Preparaciones de Acción Retardada/química , Nanofibras/química , Polímeros/química
12.
Biomolecules ; 12(9)2022 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-36139093

RESUMEN

Oral ulcers affect oral and systemic health and have high prevalence in the population. There are significant individual differences in the etiology and extent of the disease among patients. In the treatment of oral ulcers, nanofiber films can control the drug-release rate and enable long-term local administration. Compared to other drug-delivery methods, nanofiber films avoid the disadvantages of frequent administration and certain side effects. Electrospinning is a simple and effective method for preparing nanofiber films. Currently, electrospinning technology has made significant breakthroughs in energy-saving and large-scale production. This paper summarizes the polymers that enable oral mucosal adhesion and the active pharmaceutical ingredients used for oral ulcers. Moreover, the therapeutic effects of currently available electrospun nanofiber films on oral ulcers in animal experiments and clinical trials are investigated. In addition, solvent casting and cross-linking methods can be used in conjunction with electrospinning techniques. Based on the literature, more administration systems with different polymers and loading components can be inspired. These administration systems are expected to have synergistic effects and achieve better therapeutic effects. This not only provides new possibilities for drug-loaded nanofibers but also brings new hope for the treatment of oral ulcers.


Asunto(s)
Nanofibras , Úlceras Bucales , Animales , Nanofibras/uso terapéutico , Úlceras Bucales/tratamiento farmacológico , Preparaciones Farmacéuticas , Polímeros , Solventes
13.
J Sep Sci ; 34(16-17): 2305-13, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21661109

RESUMEN

Monolithic silica capillary columns synthesized following a three-level design were evaluated for the electrochromatographic separation of acidic and neutral compounds. The influences of four factors in the sol-gel synthesis, i.e. the concentrations of tetramethylorthosilicate (TMOS) and PEG in the starting mixture, the gelation temperature and the silanization modifying time, on the electrochromatographic performance of the resulting C18-silica capillary monoliths were studied. The considered responses were retention factor, resolution, symmetry factor, column efficiency, electrokinetic porosity and the equivalent length of the monolith. The four factors were varied to change the pore structure and the surface coverage with octadecyl moieties, resulting in nine stationary phases. The retentive properties of the columns were initially characterized with alkylbenzenes. Next, the separation for acetylsalicylic acid (ASA) and its related compounds was optimized and used to evaluate the performance of the nine stationary phases considering six responses. A compromise between the different responses was found around higher concentrations of tetramethylorthosilicate and PEG with a lower gelation temperature and a modifying time of 2 h. Column efficiencies up to 96,000 plates/m and resolutions above 1.9 were obtained for the acetylsalicylic acid separation, with a sufficient EOF to yield rapid analysis, which showed improvements over the center-point stationary phase.


Asunto(s)
Electrocromatografía Capilar/instrumentación , Polímeros/química , Dióxido de Silicio/química , Concentración de Iones de Hidrógeno , Polímeros/síntesis química , Porosidad , Proyectos de Investigación , Temperatura
14.
Carbohydr Polym ; 238: 116216, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-32299575

RESUMEN

An effective and biodegradable polygonatum fructan (PF) from Polygonatum cyrtonema Hua was studied as an eco-friendly corrosion inhibitor for mild steel protection in 1 M HCl, whose inhibition performance was studied by weight loss tests, electrochemical techniques, and surface analysis techniques (SECM, FTIR). The experimental results showed that PF has outstanding inhibition performance for mild steel in hydrochloric acid, and the inhibition efficiency increased with the increase of its concentration and temperature. Polarization studies indicated that PF is a mixed-type corrosion inhibitor, and its adsorption mode conforms to Langmuir isotherm, mainly chemisorption. An adsorption-related protective inhibitor film formed on the surface of mild steel was verified and investigated based on its surface analysis and characterization. Quantum chemical analysis showed that the adsorption of PF on the surface of mild steel has obvious chemical properties.


Asunto(s)
Fructanos/química , Polygonatum/química , Acero/química , Corrosión , Ácido Clorhídrico/química
15.
Zhongguo Gu Shang ; 33(9): 837-41, 2020 Sep 25.
Artículo en Zh | MEDLINE | ID: mdl-32959571

RESUMEN

OBJECTIVE: To evaluate the early clinical efficacy and safety of vesselplasty for the treatment of spinal metastases complicated by posterior wall destruction of vertebral body. METHODS: The clinical data of 19 patients(21 segments) with spinal metastases complicated by posterior wall destruction of vertebral body treated from January 2016 to January 2017 were retrospectively analyzed. There were 15 males and 4 females, aged 40 to 85 years old with a mean of (66.00±10.25) years . All patients had severe low back pain before the operation, which were diagnosed by CT as damage-type metastatic tumor of the vertebral posterior wall. All patients were treated by vesselplasty technique. Nineteen vertebrae received percutaneous unilateral pedicle puncture and two vertebrae received percutaneous bilateral pedicle puncture. VAS, ODI were recorded before operation, 1 d and 3 d after operation respectively. X-ray and CT scan were used to observe bone cement leakage and complications. RESULTS: All the operations were successful and postoperative pain was significantly relieved. Postoperative VAS score and ODI of the two groups were significantly improved (P<0.05). A small amount of bone cement leakage occurred in one vertebral body, which was a vertebral venous plexus leakage, but no clinical symptoms after operation. CONCLUSION: Vesselplasty for the treatment of spinal metastases complicated by posterior wall destruction of vertebral body can significantly reduce the symptoms of thoracolumbar back pain, improve the quality of life, reduce the incidence of bone cement leakage, and has high clinical efficacy and safety.


Asunto(s)
Fracturas por Compresión , Cifoplastia , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Neoplasias de la Columna Vertebral , Vertebroplastia , Adulto , Anciano , Anciano de 80 o más Años , Cementos para Huesos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Estudios Retrospectivos , Resultado del Tratamiento
16.
Bioresour Technol ; 272: 249-258, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30352367

RESUMEN

In this paper, solar binary chemical depolymerization, that is Solar Thermal Electrochemical Process (STEP), was implemented for an effective breaking of lignin into small molecules and hydrogen. Compared with the conventional unitary chemical thermolysis, solar binary chemical depolymerization of lignin has high efficiencies of the liquefaction and gasification with the low coke, and accompanied by the abundant production of hydrogen. And the reaction temperature of the STEP process was greatly lowered by an intervention of the electrolysis. The results showed that the total conversion and liquefaction of the lignin yielded 87.22% and 57.72% under a constant current of 0.4 A at 340 °C. Further characterizations show that lignin has been successfully decomposed into small molecules with high added-value and hydrogen by a combination of the thermolysis and electrolysis. And the particle size of aggregates and the color degree in the lignin aqueous solution was obviously decreased after the STEP process.


Asunto(s)
Hidrógeno/química , Lignina/química , Luz Solar , Electrólisis , Polimerizacion , Temperatura
17.
Anal Chim Acta ; 1048: 204-211, 2019 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-30598151

RESUMEN

A porous layer open-tubular capillary column with immobilized pH gradient (PLOT-IPG) was prepared in two steps. First, a partially filled porous layer open tubular capillary column containing active epoxy groups was synthesized by in situ polymerization of acrylamide, glycidyl methacrylate, and N,N'-methylenebisacrylamide. Then, an aqueous solution of commercial carrier ampholytes (CAs, Pharmalyte) was focused in the prepared polymer column. With the column immobilized by Pharmalyte 4.5-6.0 (narrow pH range) or Pharmalyte 3.0-10.0 (wide pH range), proteins with known pIs were separated and a good linear correlation between pI values and migration times was obtained. Meanwhile, resolution was improved compared to the traditional gradient with a wide pH range. A mixture of low molecular weight amino acids was separated with the narrow pH range PLOT-IPG column; from the obtained results, the resolution of our new column was calculated to be at most 0.09 pH unit. In addition, human serum proteins were analyzed with the newly developed wide and narrow pH range PLOT-IPG columns; its sensitivity and resolution in the narrow pH range one were better than capillary electrophoresis.


Asunto(s)
Resinas Acrílicas/química , Aminoácidos/análisis , Proteínas Sanguíneas/análisis , Resinas Acrílicas/síntesis química , Aminoácidos/química , Proteínas Sanguíneas/química , Humanos , Concentración de Iones de Hidrógeno , Focalización Isoeléctrica/instrumentación , Focalización Isoeléctrica/métodos , Punto Isoeléctrico , Porosidad , Fuerza Protón-Motriz , Reproducibilidad de los Resultados
18.
J Phys Chem B ; 112(11): 3311-4, 2008 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-18303882

RESUMEN

The structure evolution of poly(butylene adipate) (PBA) during isothermal melt crystallization and phase transition processes is investigated by Fourier transform infrared spectroscopy (FTIR). Detailed IR spectra analysis and band assignment are performed to disclose the bands sensitive to the alpha-form crystalline order of PBA. It is revealed from the in situ IR study that the functionalities within PBA chains alter simultaneously during the melt crystallization process. From the analysis of the spectral changes, it is found that band shifts take place during the phase transition process of PBA from its metastable beta-form crystal to the stable alpha-form. Notable band shifts in the 1300-1100 cm(-1) region indicate that the twist of polymer chains in the alpha-form is located in the C-O-C and C-O linkages. Moreover, the results elucidated that the different segments of molecular chains tune up their conformations synchronously during the beta to alpha crystal transition process of PBA. It is suggested that the betaalpha phase transition process proceeds randomly throughout the solid at a constant rate.


Asunto(s)
Materiales Biocompatibles/química , Butileno Glicoles/química , Transición de Fase , Polímeros/química , Cristalización , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Factores de Tiempo
19.
J Chromatogr A ; 1499: 196-202, 2017 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-28396086

RESUMEN

A novel fibrous mesoporous silica nanoparticles (fSiO2) stationary phase grafted with polymer (Poly (2-(dimethylamino) ethyl methacrylate) (PDMAEMA) was developed for open tubular capillary electrochromatography (OT-CEC). The preparation procedure included synthesizing fSiO2 through biphase stratification approach, removing the surfactants, silanization and in situ graft polymerization with monomers via atom transfer radical polymerization (ATRP). Subsequently, PDMAEMA-modified mesoporous silica nanoparticles (P-fSiO2)/ethanol solution was immobilized onto the inner surface of the pretreated capillary and functionalized with octadecylsilane to fabricate the open-tubular column. Separation of polycyclic aromatic hydrocarbons (PAHs) and proteins were carried out to evaluate the performance of the column in CEC. The run-to-run, day-to-day and column-to-column reproducibility in terms retention time of naphthalene was 1.9%, 2.2%, and 3.7%, respectively. The effects of solvent concentration and pH on the separation were evaluated. The method was also used for the separation of real bio-sample, egg white proteins.


Asunto(s)
Electrocromatografía Capilar/métodos , Nanopartículas/química , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Polímeros/química , Proteínas/aislamiento & purificación , Dióxido de Silicio/química , Electrocromatografía Capilar/instrumentación , Metacrilatos , Nylons , Hidrocarburos Policíclicos Aromáticos/química , Proteínas/química
20.
Medicine (Baltimore) ; 96(25): e7190, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28640101

RESUMEN

BACKGROUND: In the past, the efficacy of local infiltration of liposomal bupivacaine for total hip arthroplasty (THA) patients was in debate. Therefore, this meta-analysis was conducted to determine whether local infiltration of liposomal bupivacaine provides better pain relief after THA. METHODS: We searched Web of Science, PubMed, Embase, and the Cochrane Library databases to the April 2017. Any studies comparing liposomal bupivacaine and traditional bupivacaine were included in our meta-analysis. The outcomes included visual analog scale (VAS) at 24, 48, and 72 hours, total morphine consumption at 24 hours, and the length of hospital stay. We assessed the pooled data using a random-effect model. RESULTS: Six studies were finally included in this meta-analysis. Our pooled data analysis demonstrated that liposomal bupivacaine was more effective than the traditional bupivacaine in terms of VAS at 24 hours (P  =  .018) and the length of hospital stay (P  =  .000). There was no significant difference in terms of the VAS at 48 and 72 hours and total morphine consumption at 24 hours (P >.05). CONCLUSION: Compared with the traditional bupivacaine, liposomal bupivacaine shows better pain control at 24 hours and reduces the length of hospital stay after THA. Its economic costs must be assessed in multimodal center randomized controlled trials when being recommended as a long-acting alternative analgesic agent for a THA patient.


Asunto(s)
Anestésicos Locales/administración & dosificación , Artroplastia de Reemplazo de Cadera , Bupivacaína/administración & dosificación , Dolor Postoperatorio/tratamiento farmacológico , Humanos , Liposomas
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