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1.
BMC Oral Health ; 22(1): 229, 2022 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-35681195

RESUMEN

BACKGROUND: Previous studies have described and recorded abnormal root morphology; however, most of these studies were based on two-dimensional periapical or panoramic radiographs, and only a few studies have quantified it. We aimed to combine two-dimensional periapical radiographs and three-dimensional cone-beam computed tomography (CBCT) to conduct qualitative judgments and quantitative analyses of normal and conical roots, and explore the clinical diagnostic method of normal and conical roots based on intraoral radiographs and CBCT. METHODS: The conical root was identified visually on periapical radiographs as the clinical gold standard. All teeth were divided into the cone-rooted teeth (CRT) or normal-rooted teeth (NRT) groups. Furthermore, differences in root length (RL), root surface area (RSA), and root volume (RV) of conical and normal roots in the maxillary premolars on CBCT were compared. Receiver operator characteristic curves were generated, and the area under the curve (AUC) and cut-off values were calculated to evaluate the diagnostic value of RV, RSA, RV/RL, and RSA/RL. RESULTS: The RSAs of NRT and CRT were 236.88 ± 27.93 mm2 and 207.98 ± 27.80 mm2, respectively (P = 0.000). The mean RV in the CRT group was lower than that in the NRT group, and the difference was statistically significant (253.40 ± 41.98 mm3 vs. 316.93 ± 49.89 mm3, P = 0.000). The RSA and RV of conical roots in single root premolars were 12.29% and 19.33% less than those of normal roots, respectively. The AUC values of RSA/RL and RV/RL were 0.87 and 0.89, respectively, and the best cut-off values were 19.61 for RSA/RL (if RSA/RL was < 19.61, the teeth were considered CRT) and 24.05 for RV/RL (if RV/RL was < 24.05, the teeth were considered CRT). CONCLUSIONS: CBCT has significant diagnostic value in the clinical evaluation of conical roots. RSA/RL and RV/RL were the best parameters with the largest AUC and high sensitivity and specificity.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Raíz del Diente , Diente Premolar/anatomía & histología , Diente Premolar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Humanos , Raíz del Diente/anatomía & histología , Raíz del Diente/diagnóstico por imagen
2.
Analyst ; 140(16): 5707-15, 2015 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-26153569

RESUMEN

We report a facile method to synthesise flexible 3D surface-enhanced Raman scattering (SERS) substrates, using poly-m-phenylenediamine/polyacrylonitrile (PmPD/PAN) nanofiber mats as templates to self-assemble citrate-stabilized Ag nanocrystals (AgNCs), such as Ag nanoparticles (AgNPs), Ag nanotriangles (AgNTs) or Ag nanodisks (AgNDs). The SERS performances of AgNC@2D and AgNC@3D substrates were compared using 4-MBA as the probe molecule. The effect of the extinction wavelength as well as the density and morphology of the AgNCs on the SERS enhancement effect was explored. The results suggest that the 3D AgNT@PmPD/PAN nanofiber mat exhibits the highest SERS sensitivity and the lowest relative standard deviation (RSD) value. The detection limit of 4-MBA is as low as 10(-8) M, making the nanofiber mat a promising candidate for the SERS detection of chemical molecules. In addition, this study provides a simple route for the fabrication of SERS substrates with different types of noble metals and materials with strong SERS enhancement performance.


Asunto(s)
Resinas Acrílicas/química , Nanopartículas del Metal/química , Nanofibras/química , Fenilendiaminas/química , Plata/química , Espectrometría Raman , Citratos/química
3.
Yao Xue Xue Bao ; 50(1): 15-20, 2015 Jan.
Artículo en Zh | MEDLINE | ID: mdl-25924469

RESUMEN

Molecular imprinting technique (MIT) involves the synthesis of polymer in the presence of a template to produce complementary binding sites in terms of its size, shape and functional group orientation. Such kind of polymer possesses specific recognition ability towards its template molecule. Despite the rapid development of MIT over the years, the majority of the template molecules that have been studied are small molecules, while molecular imprinting of proteins remains a significant yet challenging task due to their large size, structural flexibility and complex conformation. This review, we summarized the research findings over the past years, and discussed the nano-reinforcing materials used to prepare molecular imprinting of proteins and the perspective of these nano-reinforcing materials.


Asunto(s)
Impresión Molecular , Nanoestructuras/química , Proteínas/química , Sitios de Unión , Conformación Molecular , Polímeros/química
4.
Comput Methods Biomech Biomed Engin ; 26(7): 789-798, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35748704

RESUMEN

3D printed Titanium alloy is widely used as a material of artificial joints and its mechanical properties is a key factor for improving operation results. Because the elastic modulus of the 3 D printed titanium alloy specimen was related to the size of the metal blank. It is very difficult to identify mechanical parameters by traditional mechanics experiments. In this paper, according to the inverse analysis principle of the parameter estimation, a response surface methodology (RSM) was proposed to identify the mechanical parameters, based on finite element inverse analysis. The finite element models of femoral prosthesis stem were established in line with compression experiments. The material parameters were combined by central composite design (CCD), and the response surface (RS) models were constructed using a quadratic polynomial with cross terms and optimized using a genetic algorithm (GA). Finally, the best mechanical parameter combination of the femoral prosthesis was calculated. The calculated elastic modulus and Poisson's ratio of a 3 D printed titanium alloy femoral prosthesis stem were 109.07 GPa and 0.29, respectively, with the elastic modulus error being very small. The proposed method is effective and can be extended for the identification of mechanical parameters in other 3 D printed models.


Asunto(s)
Miembros Artificiales , Prótesis de Cadera , Aleaciones , Titanio , Implantación de Prótesis , Impresión Tridimensional , Análisis de Elementos Finitos , Diseño de Prótesis
5.
BMC Pharmacol Toxicol ; 24(1): 52, 2023 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-37828600

RESUMEN

BACKGROUND: Botulinum toxin (BoNT) injection is an important adjunctive method to treat sialorrhea. The purpose of this systematic review was to analyze the effect and safety of BoNT injections in the intervention of sialorrhea with Parkinson's disease (PD). METHODS: We searched PubMed, Web Of Science (WOS), Scopus, Cochrane CENTRAL, and Embase from inception until April 2022. Randomized controlled trials or randomized crossover trials comparing BoNT with placebo in sialorrhea with PD were eligible. PRISMA guidelines were used to carry out the meta-analysis. The Drooling Severity Frequency Scale (DSFS) score and the number of adverse events (AEs) were the primary and secondary outcomes, respectively. Standardized mean differences (SMDs) and risk differences (RDs) are used to express continuous and categorical outcomes, respectively. Heterogeneity among these studies was evaluated using I2 tests. We used the GRADE tool to assess the certainty of evidence (COE). RESULTS: Eight articles involving 259 patients compared BoNT injections with a placebo for PD with sialorrhea. This meta-analysis showed a significant reduction in DSFS scores between BoNT injections and placebo (SMD=-0.98; 95% CI, -1.27 to 0.70, p<0.001; COE: high). This meta-analysis showed a significant difference in AEs between BoNT injections and placebo (RD=0.15; 95% CI, 0.05 to 0.24, p=0.002; COE: low). CONCLUSIONS: The pooled results suggest that BoNT injections have some effect on DSFS scores with sialorrhea caused by PD. There are also mild adverse events, which generally recover within a week or so. The results indicate that BoNT injection is one of the treatments for sialorrhea caused by PD, but we need to pay attention to adverse events. In addition, the follow-up time was extended to observe oral hygiene, ulceration or dental caries, and digestive function. TRIAL REGISTRATION: Our review protocol was registered on PROSPERO (42021288334).


Asunto(s)
Toxinas Botulínicas Tipo A , Caries Dental , Enfermedad de Parkinson , Sialorrea , Humanos , Toxinas Botulínicas Tipo A/efectos adversos , Sialorrea/etiología , Sialorrea/complicaciones , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/tratamiento farmacológico , Caries Dental/inducido químicamente , Caries Dental/complicaciones , Caries Dental/tratamiento farmacológico , Resultado del Tratamiento
6.
Huan Jing Ke Xue ; 44(11): 6267-6278, 2023 Nov 08.
Artículo en Zh | MEDLINE | ID: mdl-37973109

RESUMEN

Microplastics(MPs), as a new type of environmental pollutants, have gradually attracted widespread attention since they were introduced by British scientists in 2004. Soil is an important accumulation site for microplastics, which can expand the scope of contamination and accumulate with agricultural practices such as irrigation and tillage. Microplastics in soil cause a variety of toxicities to terrestrial plants. The small particle size, difficult degradation, and strong adsorption capacity bring a challenge to the microplastic pollution treatment of soil. In this study, the toxicity of microplastics to terrestrial plants was reviewed in terms of their direct or indirect toxicity and combined effects with other pollutants, mainly in terms of mechanical injury, induction of oxidative stress, and cytotoxicity and genotoxicity to plants, resulting in plant growth and plant tissue metabolism obstruction. In general, the toxicity of microplastics depended on the polymer type, size, and dose; plant tolerance; and exposure conditions. In addition, the production of secondary microplastics and endogenous contaminants during their degradation in soil enhanced the biotoxicity of microplastics. Further, the physical, chemical, and microbial degradation mechanisms of microplastics were introduced in this study based on the current research. At first, the physical and chemical degradation of microplastics mainly occurred by changing the particle size and surface properties of microplastics and producing intermediates. Then, smaller-sized microplastics and their intermediates could eventually be converted to water and carbon dioxide through physical, chemical, and biological functions. Finally, further prospects regarding soil microplastics were introduced, and we provided information for future improvement and pollution control of microplastics.


Asunto(s)
Contaminantes Ambientales , Contaminantes del Suelo , Microplásticos/toxicidad , Suelo/química , Plásticos/toxicidad , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Agricultura , Plantas , Ecosistema
7.
ACS Appl Mater Interfaces ; 13(28): 33546-33556, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34235930

RESUMEN

Industrial pollution and harmful chemicals seriously affect environment and human health. Styrene is a common air toxicant with widespread exposure sources, including smoking, automobile exhaust, and plastic pollutants. Phenylglyoxylic acid (PGA) is a typical biomarker for exposed styrene. Therefore, it is crucial to quickly identify and quantitatively detect PGA. Herein, an ultrastable terbium metal-organic framework (Tb-MOF 1) was developed, and the luminescence film (1/PLA) consisting of polylactic acid (PLA) and 1 was fabricated as a sensor for rapid detection of PGA. The sensor possesses the advantages of efficient detection [limit of detection (LOD) is 1.05 × 10-4 mg/mL] and rapid response speed (less than 10 s) for PGA in urine. Furthermore, this sensor exhibits high stability, outstanding anti-interference ability, and excellent recyclability. Based on this film technology, a paper-based probe was then developed for portable and convenient detection. The probe could easily distinguish different concentrations of PGA under the naked eye toward practical sensing applications. Meanwhile, photoinduced electron transfer was demonstrated to be responsible for the luminescence sensing. Hence, this study indicates that Tb-MOF is a promising material to detect PGA for evaluating the effect of styrene on the body.


Asunto(s)
Glioxilatos/orina , Sustancias Luminiscentes/química , Ácidos Mandélicos/orina , Estructuras Metalorgánicas/química , Biomarcadores/orina , Humanos , Límite de Detección , Sustancias Luminiscentes/síntesis química , Mediciones Luminiscentes , Estructuras Metalorgánicas/síntesis química , Poliésteres/química , Terbio/química
8.
Shanghai Kou Qiang Yi Xue ; 30(4): 444-448, 2021 Aug.
Artículo en Zh | MEDLINE | ID: mdl-34693443

RESUMEN

PURPOSE: To investigate the clinical efficacy and safety of bipolar coagulation forceps combined with 1% lauromacrogol foam sclerotherapy in the treatment of microcystic lymphatic malformation of tongue. METHODS: The clinical data of 16 patients with microcystic lymphatic malformation of the tongue admitted to the Department of Stomatology of Foshan First People's Hospital from April 2017 to April 2020 were retrospectively analyzed, including 7 males and 9 females, aging from 15 months to 21 years. The average age of patients was 8.32±1.21 years. The efficacy and complications of the patients were evaluated. RESULTS: All 16 patients were followed up for 6 to 12 months. The clinical response was evaluated as eleven patients (68.75%) for grade Ⅳ, three (18.75%) for grade Ⅲ, two (12.5%) for grade Ⅱ, and the effective rate was 87.5%. Necrosis of tongue mucosa and muscle occurred in 1 patient. CONCLUSIONS: Bipolar coagulation forceps combined with 1% lauromacrogol foam sclerotherapy is a minimally invasive, safe and effective treatment for tongue microcystic lymphatic malformation.


Asunto(s)
Escleroterapia , Lengua , Niño , Femenino , Humanos , Masculino , Polidocanol , Estudios Retrospectivos , Instrumentos Quirúrgicos
9.
Microb Ecol ; 60(3): 677-90, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20614117

RESUMEN

Oral microbiota plays a vital role in maintaining the homeostasis of oral cavity. Dental caries are among the most common oral diseases in children and pathogenic bacteria contribute to the development of the disease. However, the overall structure of bacterial communities in the oral cavity from children with dental caries has not been explored deeply heretofore. We used high-throughput barcoded pyrosequencing and PCR-denaturing gradient gel electrophoresis (DGGE) to examine bacterial diversity of oral microbiota in saliva and supragingival plaques from 60 children aged 3 to 6 years old with and without dental caries from China. The multiplex barcoded pyrosequencing was performed in a single run, with multiple samples tagged uniquely by multiplex identifiers. As PCR-DGGE analysis is a conventional molecular ecological approach, this analysis was also performed on the same samples and the results of both approaches were compared. A total of 186,787 high-quality sequences were obtained for evaluating bacterial diversity and 41,905 unique sequences represented all phylotypes. We found that the oral microbiota in children was far more diverse than previous studies reported, and more than 200 genera belonging to ten phyla were found in the oral cavity. The phylotypes in saliva and supragingival plaques were significantly different and could be divided into two distinct clusters (p < 0.05). The bacterial diversity in oral microbiome analyzed by PCR-DGGE and barcoded pyrosequencing was employed to cross validate the data sets. The genera of Streptococcus, Veillonella, Actinomyces, Granulicatella, Leptotrichia, and Thiomonas in plaques were significantly associated with dental caries (p < 0.05). The results showed that there was no one specific pathogen but rather pathogenic populations in plaque that significantly correlated with dental caries. The enormous diversity of oral microbiota allowed for a better understanding of oral microecosystem, and these pathogenic populations in plaque provide new insights into the etiology of dental caries and suggest new targets for interventions of the disease.


Asunto(s)
Bacterias/genética , Caries Dental/microbiología , Metagenoma , Boca/microbiología , Niño , Preescolar , China , Código de Barras del ADN Taxonómico , ADN Bacteriano/genética , Electroforesis en Gel de Gradiente Desnaturalizante , Placa Dental/microbiología , Femenino , Humanos , Masculino , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Saliva/microbiología
10.
Sci Total Environ ; 699: 134381, 2020 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-31677466

RESUMEN

This study investigated the pyrolysis of lignin pyrolysis in a temperature region from 200 to 800 °C, aiming to understand influence of pyrolysis temperature on evolution of structures of the resulting char. The results showed that fusion of the ring structure initiated at 200 °C, where the C/H ratio in the char was equal to that in naphthalene (two fused rings). The C/H ratio in the char obtained at 350 °C corresponded to that in pyrene (four fused rings), while the char produced at 550 °C was equivalent to 20 fused benzene rings in terms of C/H ratio. The increasing pyrolysis temperature also shifted the oxygen-containing functionalities such as the carbonyl, esters, ketones in the bio-oil to the ether functionality that had a higher thermal stability. The DRIFTS study of pyrolysis of lignin showed that drastic changes of the functionalities and the internal structure of the char occurred in a narrow temperature region from 520 to 530 °C. The carbonyl functionality and the aliphatic structure were eliminated, and new conjugated π-bond systems formed.


Asunto(s)
Carbón Orgánico/química , Lignina/química , Pirólisis , Temperatura , Biocombustibles , Biomasa , Calor
11.
Fitoterapia ; 146: 104711, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32860875

RESUMEN

Penctrimertone (1), a novel citrinin dimer bearing a 6/6/6/6 tetracyclic ring scaffold, along with two known compounds xerucitrinic acid A (2) and citrinin (3) were isolated from the endophytic fungus Penicillium sp. T2-11. Their structures were unequivocally established by a comprehensive interpretation of the spectroscopic data, with the stereochemistry for 1 was defined by a combination of TDDFT-ECD calculations and the DP4+ probability analysis based on NMR chemical shift calculations. Bioassays revealed that compound 1 exhibited noticeable antimicrobial activities and moderate cytotoxicity. A plausible biosynthetic pathway of 1 was also proposed.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos/farmacología , Citrinina/farmacología , Gastrodia/microbiología , Penicillium/química , Antibacterianos/aislamiento & purificación , Antineoplásicos/aislamiento & purificación , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Línea Celular Tumoral , Mentón , Citrinina/aislamiento & purificación , Endófitos/química , Humanos , Estructura Molecular , Rizoma/microbiología
12.
Sci Rep ; 9(1): 2661, 2019 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-30804467

RESUMEN

Hand-foot-and-mouth disease (HFMD) is a highly contagious viral infection, and real-time predicting of HFMD outbreaks will facilitate the timely implementation of appropriate control measures. By integrating a susceptible-exposed-infectious-recovered (SEIR) model and an ensemble Kalman filter (EnKF) assimilation method, we developed an integrated compartment model and assimilation filtering forecast model for real-time forecasting of HFMD. When applied to HFMD outbreak data collected for 2008-11 in Beijing, China, our model successfully predicted the peak week of an outbreak three weeks before the actual arrival of the peak, with a predicted maximum infection rate of 85% or greater than the observed rate. Moreover, dominant virus types enterovirus 71 (EV-71) and coxsackievirus A16 (CV-A16) may account for the different patterns of HFMD transmission and recovery observed. The results of this study can be used to inform agencies responsible for public health management of tailored strategies for disease control efforts during HFMD outbreak seasons.


Asunto(s)
Brotes de Enfermedades , Enterovirus Humano A , Enfermedad de Boca, Mano y Pie/epidemiología , Enfermedad de Boca, Mano y Pie/virología , Modelos Teóricos , Beijing/epidemiología , Enfermedad de Boca, Mano y Pie/transmisión , Humanos , Vigilancia en Salud Pública , Estaciones del Año
13.
Carbohydr Polym ; 216: 167-179, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31047053

RESUMEN

In this paper, acid-catalyzed conversion of nine sugars (xylose, glucose, fructose, galactose, sucrose, maltose, lactose, raffinose, and ß-cyclodextrin) with different sizes, steric structures and functionalities were investigated and impacts of the varied sugars on structures of resulting polymers were focused. Under similar reaction conditions, the yields of the carbon materials (insoluble polymers) formed followed the order: xylose ¼ lactose > galactose > ß-cyclodextrin > maltose > sucrose > fructose > glucose > raffinose. Increasing temperature enhanced transformation of soluble oligomers into insoluble ones. Morphologies of the carbon materials were closely related to sugar structures. Diameters of carbon materials (microsphere form) obtained from the disaccharides and oligosaccharides were larger than that of monosaccharides. Furthermore, the microspheres from oligosaccharides had a higher affinity to each other, resulting from continued polymerization as some reactive functionalities were retained in carbon materials. In addition, graphite structure was formed in the carbon materials, even at 160 °C.


Asunto(s)
Monosacáridos/química , Oligosacáridos/química , Polímeros/química , beta-Ciclodextrinas/química , Catálisis , Hidrólisis , Microesferas , Estructura Molecular , Polímeros/síntesis química , Solubilidad , Ácidos Sulfúricos/química , Temperatura
14.
Ying Yong Sheng Tai Xue Bao ; 29(4): 1259-1265, 2018 Apr.
Artículo en Zh | MEDLINE | ID: mdl-29726236

RESUMEN

The objective of this study was to investigate the rate of nitrogen mineralization in various soil layers (0-10, 10-20, and 20-30 cm) and its influencing factors under plastic film mulching ridge-furrow in a corn field of Wulongchi small watershed, Danjiangkou Reservoir Area. Results showed that the rate of soil ammonification decreased with soil depth during the entire maize growth period. The rate of nitrification in seedling, jointing, and heading stages decreased in the following order: 10-20 cm > 0-10 cm > 20-30 cm, while it increased with soil depth in maturation stage. The rate of soil nitrogen mineralization decreased with the increases in soil depth in the seedling, jointing and heading stages, whereas an opposite pattern was observed in maturation stage. Compared with non-filming, film mulching promoted the soil ammonification process in 0-10 cm and the soil nitrification and nitrogen mineralization processes in jointing, heading, and maturation stages in both 0-10 and 10-20 cm. However, the rates of soil nitrification and nitrogen mineralization under film mulching were much lower than those under non-filming in seedling stage. The stepwise regression analysis indicated that the main factors influencing soil nitrogen mineralization rate varied with soil depth. Soil moisture and total N content were the dominant controller for variation of soil nitrogen mineralization in 0-10 cm layer. Soil temperature, moisture, and total N content were dominant controller for that in 10-20 cm layer. Soil temperature drove the variation of soil nitrogen mineralization in 20-30 cm layer.


Asunto(s)
Nitrógeno/química , Suelo/química , Agricultura , China , Nitrificación , Plásticos , Temperatura , Agua , Zea mays
15.
Ying Yong Sheng Tai Xue Bao ; 28(2): 581-588, 2017 Feb.
Artículo en Zh | MEDLINE | ID: mdl-29749167

RESUMEN

Soil net nitrogen mineralization in cropland has a great influence on both agricultural non-point source pollution and soil nitrogen loss. A field plot experiment was conducted to explore the temporal variation of soil net nitrogen mineralization under plastic film mulching ridge-furrow in Wulongchi small watershed during summer maize growing period. Results showed that the soil net ammonification, nitrification, and nitrogen mineralization were significantly greater than those of non-mulched treatment, and the differences were 6.63, 12.96 and 19.59 mg·kg-1, respectively. During the summer maize growth period, the rate of soil net ammonification was high at seedling stage, low at heading stage, and high at maturation stage. Both the rates of soil net nitrification and nitrogen mineralization were high at jointing stage, low at heading stage, and high at maturation stage. The rate of soil net nitrogen mineralization under plastic film mulched had significant linear relation with the contents of soil total nitrogen, nitrate nitrogen, and soil water. In conclusion, the improved condition of soil water and temperature under plastic film mulched cultivation of summer maize in the growing period promoted soil net nitrogen mineralization.


Asunto(s)
Nitrógeno , Suelo , Zea mays , China , Plásticos
16.
Cell Death Dis ; 7(10): e2435, 2016 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-27787522

RESUMEN

As wear particles-induced osteolysis still remains the leading cause of early implant loosening in endoprosthetic surgery, and promotion of osteoclastogenesis by wear particles has been confirmed to be responsible for osteolysis. Therapeutic agents targeting osteoclasts formation are considered for the treatment of wear particles-induced osteolysis. In the present study, we demonstrated for the first time that desferrioxamine (DFO), a powerful iron chelator, could significantly alleviate osteolysis in an ultrahigh-molecular-weight polyethylene (UHMWPE) particles-induced mice calvaria osteolysis model. Furthermore, DFO attenuated calvaria osteolysis by restraining enhanced inflammatory osteoclastogenesis induced by UHMWPE particles. Consistent with the in vivo results, we found DFO was also able to inhibit osteoclastogenesis in a dose-dependent manner in vitro, as evidenced by reduction of osteoclasts formation and suppression of osteoclast specific genes expression. In addition, DFO dampened osteoclasts differentiation and formation at early stage but not at late stage. Mechanistically, the reduction of osteoclastogenesis by DFO was due to increased heme oxygenase-1 (HO-1) expression, as decreased osteoclasts formation induced by DFO was significantly restored after HO-1 was silenced by siRNA, while HO-1 agonist COPP treatment enhanced DFO-induced osteoclastogenesis inhibition. In addition, blocking of p38 mitogen-activated protein kinase (p38MAPK) signaling pathway promoted DFO-induced HO-1 expression, implicating that p38 signaling pathway was involved in DFO-mediated HO-1 expression. Taken together, our results suggested that DFO inhibited UHMWPE particles-induced osteolysis by restraining inflammatory osteoclastogenesis through upregulation of HO-1 via p38MAPK pathway. Thus, DFO might be used as an innovative and safe therapeutic alternative for treating wear particles-induced aseptic loosening.


Asunto(s)
Deferoxamina/uso terapéutico , Hemo-Oxigenasa 1/metabolismo , Inflamación/patología , Osteoclastos/patología , Osteogénesis , Osteólisis/inducido químicamente , Osteólisis/tratamiento farmacológico , Polietilenos/efectos adversos , Actinas/metabolismo , Animales , Resorción Ósea/genética , Resorción Ósea/patología , Deferoxamina/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Inflamación/complicaciones , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Osteogénesis/efectos de los fármacos , Osteogénesis/genética , Osteólisis/complicaciones , Osteólisis/patología , Ligando RANK/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
17.
Huan Jing Ke Xue ; 37(11): 4212-4219, 2016 Nov 08.
Artículo en Zh | MEDLINE | ID: mdl-29964672

RESUMEN

As an important form of agricultural non-point source pollution, soil nitrogen leaching deteriorates water quality. Compared with non-mulching cultivated land, field experiment explored the change characteristics of soil nitrogen leaching under plastic film mulching ridge-furrow in Wulongchi small watershed during summer maize growing period. The results showed that the amounts of mulching tillage soil TN and NO3--N leaching were significantly lower than those with non-mulched treatment, by 25.68% and 20.25%, respectively. With the advance of the summer maize growth period, leaching amount of mulched soil TN was highest at seedling stage, lowest at heading stage and higher in maturation period; leaching amount of mulched soil NO3--N was highest at seedling stage, lowest in maturation period; leaching amount of mulched soil NH4+-N was lower at seedling stage, increased to the peak at the jointing stage, decreased to the valley value at heading stage, and obviously increased in maturation period. Linear function relationship was found between mulched soil TN leaching and TN content, while exponential relationship was found between mulched soil NO3--N leaching and NO3--N content. In addition, there was linear function relationship of mulched soil TN and NO3--N leaching amount with soil moisture and rainfall. It was concluded that the plastic film mulched on summer maize could reduce the leaching loss of soil nitrogen, and it would have a significant effect on the reduction of reservoir area of agricultural non-point source pollution.


Asunto(s)
Nitrógeno/análisis , Plásticos , Suelo/química , Contaminantes Químicos del Agua/análisis , Zea mays/crecimiento & desarrollo , Agricultura , China , Fertilizantes
18.
J Biomed Mater Res A ; 104(10): 2515-27, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27227768

RESUMEN

The regeneration capacity of osteoporotic bones is generally lower than that of normal bones. Current methods of osteoporotic bone defect treatment are not always satisfactory. Recent studies demonstrate that activation of the hypoxia inducible factor-1α (HIF-1α) pathway, by genetic methods or hypoxia-mimicking agents, could accelerate bone regeneration. However, little is known as to whether modulating the HIF-1α pathway promotes osteoporotic defect healing. To address this problem in the present study, we first demonstrated that HIF-1α and vascular endothelial growth factor expression levels are lower in osteoporotic bones than in normal bones. Second, we loaded poly(Lactic-co-glycolic acid) (PLGA) with the hypoxia-mimetic agent deferoxamine (DFO). DFO released from PLGA had no significant effect on the proliferation of mesenchymal stem cells (MSCs); however, DFO did enhance the osteogenic differentiation of MSCs. In addition, DFO upregulated the mRNA expression levels of angiogenic factors in MSCs. Endothelial tubule formation assays demonstrate that DFO promoted angiogenesis in human umbilical vein endothelial cells. Third, untreated PLGA scaffolds (PLGA group) or DFO-containing PLGA (PLGA + DFO group) were implanted into critically sized osteoporotic femur defects in ovariectomized rats. After treatment periods of 14 or 28 days, micro-CT, histological, CD31 immunohistochemical, and dynamic bone histomorphometric analyses showed that DFO dramatically stimulated bone formation and angiogenesis in a critically sized osteoporotic femur defect model. Our in vitro and in vivo results demonstrate that DFO may promote the healing of osteoporotic bone defects due to enhanced angiogenesis and osteogenesis. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2515-2527, 2016.


Asunto(s)
Deferoxamina/administración & dosificación , Deferoxamina/uso terapéutico , Ácido Láctico/química , Neovascularización Fisiológica/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Osteoporosis/tratamiento farmacológico , Ácido Poliglicólico/química , Andamios del Tejido/química , Animales , Regeneración Ósea/efectos de los fármacos , Células Cultivadas , Deferoxamina/farmacología , Femenino , Fémur/irrigación sanguínea , Fémur/efectos de los fármacos , Fémur/metabolismo , Fémur/patología , Células Endoteliales de la Vena Umbilical Humana , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/análisis , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Osteoporosis/metabolismo , Osteoporosis/patología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/análisis , Factor A de Crecimiento Endotelial Vascular/metabolismo , Cicatrización de Heridas/efectos de los fármacos
19.
Adv Healthc Mater ; 5(8): 907-18, 2016 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-26891197

RESUMEN

Nonhealing chronic wounds on foot are one of the most dreaded complications of diabetes, and biomedical scaffolds remain an attractive option for repairing or regenerating tissues. Accelerating angiogenesis in the early stage after injury is critical to wound healing process; however, the scaffolds accelerate the angiogenesis in the beginning but with the acceleration of vessel network formation the scaffold network hinders the process. In this study, the water soluble drugs-loaded hydrogel nanofibrous scaffolds are designed for rapidly recruiting angiogenesis relative cells and promoting wound healing. The sustained release profile of desferrioxamine (DFO), which continues for about 72 h, leads to significantly increase of neovascularization. The majority of the scaffold is degraded in 14 d, leaving enough space for cell proliferation and vessel formation. The in vitro results show that the scaffolds upregulate the expression of Hif-1α and vascular endothelial growth factor, and enhance the interaction between fibroblasts and endothelial cells. The in vivo studies show a higher expression of angiogenesis related cytokines. This study demonstrates that the DFO released from hydrogel nanofibrous scaffolds of quick degradation can interfere with the required prolyl-hydroxylases cofactors by acting as Fe(2+) chelator and upregulate the expression of Hif-1α, leading to a significant increase of the neovascularization.


Asunto(s)
Diabetes Mellitus Experimental/patología , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Nanofibras/química , Neovascularización Fisiológica/efectos de los fármacos , Andamios del Tejido/química , Regulación hacia Arriba , Animales , Materiales Biocompatibles/farmacología , Quitosano/química , Deferoxamina/farmacología , Deferoxamina/uso terapéutico , Dermis/citología , Diabetes Mellitus Experimental/tratamiento farmacológico , Liberación de Fármacos , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/ultraestructura , Fluorescencia , Humanos , Inmunohistoquímica , Masculino , Nanofibras/ultraestructura , Alcohol Polivinílico/química , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Cicatrización de Heridas
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