Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
BMC Pulm Med ; 24(1): 220, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702679

RESUMEN

BACKGROUND: Recent research suggests that periodontitis can increase the risk of chronic obstructive pulmonary disease (COPD). In this study, we performed two-sample Mendelian randomization (MR) and investigated the causal effect of periodontitis (PD) on the genetic prediction of COPD. The study aimed to estimate how exposures affected outcomes. METHODS: Published data from the Gene-Lifestyle Interaction in the Dental Endpoints (GLIDE) Consortium's genome-wide association studies (GWAS) for periodontitis (17,353 cases and 28,210 controls) and COPD (16,488 cases and 169,688 controls) from European ancestry were utilized. This study employed a two-sample MR analysis approach and applied several complementary methods, including weighted median, inverse variance weighted (IVW), and MR-Egger regression. Multivariable Mendelian randomization (MVMR) analysis was further conducted to mitigate the influence of smoking on COPD. RESULTS: We chose five single-nucleotide polymorphisms (SNPs) as instrumental variables for periodontitis. A strong genetically predicted causal link between periodontitis and COPD, that is, periodontitis as an independent risk factor for COPD was detected. PD (OR = 1.102951, 95% CI: 1.005-1.211, p = 0.039) MR-Egger regression and weighted median analysis results were coincident with those of the IVW method. According to the sensitivity analysis, horizontal pleiotropy's effect on causal estimations seemed unlikely. However, reverse MR analysis revealed no significant genetic causal association between COPD and periodontitis. IVW (OR = 1.048 > 1, 95%CI: 0.973-1.128, p = 0.2082) MR Egger (OR = 0.826, 95%CI:0.658-1.037, p = 0.1104) and weighted median (OR = 1.043, 95%CI: 0.941-1.156, p = 0.4239). The results of multivariable Mendelian randomization (MVMR) analysis, after adjusting for the confounding effect of smoking, suggest a potential causal relationship between periodontitis and COPD (P = 0.035). CONCLUSION: In this study, periodontitis was found to be independent of COPD and a significant risk factor, providing new insights into periodontitis-mediated mechanisms underlying COPD development.


Asunto(s)
Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple , Enfermedad Pulmonar Obstructiva Crónica , Fumar , Humanos , Enfermedad Pulmonar Obstructiva Crónica/genética , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Factores de Riesgo , Fumar/epidemiología , Fumar/efectos adversos , Periodontitis/genética , Periodontitis/epidemiología , Índice de Severidad de la Enfermedad , Predisposición Genética a la Enfermedad , Enfermedades Periodontales/genética , Enfermedades Periodontales/epidemiología
2.
Ecotoxicol Environ Saf ; 277: 116389, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38657458

RESUMEN

Microplastics (MPs), recognized as an emerging environmental menace, have been extensively investigated in both marine and terrestrial fauna. This study is comprehensive to investigate how polystyrene (PS) affects ruminant animals. The experimental design comprised 24 individually housed lambs, divided into a CON group (diet without PS) and three PS-exposed (25 µm, 50 µm, 100 µm) groups, each with six lambs, the exposure of PS was 100 mg/day, and the duration of exposure was 60 days. The study yielded noteworthy results: (ⅰ) PS leads to a decrease in average daily gain along with an increase in feed conversion rate. (ⅱ) PS decreases rumen ammonia nitrogen. The rumen microbiota diversity remains consistent. However, the relative abundance of Bacteroidetes and Actinobacteria increased in the PS-exposed groups, while the relative abundance of Coriobacteriales_incertae_Sedis and Prevotellaceae_YAB2003_group decreased. (ⅲ) PS leads to decrease in hemoglobin, thrombocytocrit, and albumin levels in lamb blood, thus triggering oxidative stress accumulation, along with swelling of the kidneys and liver. (ⅳ) PS inflicts severe damage to jejunum, consequently impacting digestion and absorption. (ⅴ) PS reduces meat quality and the nutritional value. In conclusion, PS-exposure inhibited lambs' digestive function, adversely affects blood and organs' health status, reducing average daily gain and negatively influencing meat quality. PS particles of 50-100 µm bring worse damage to lambs. This research aims to fill the knowledge void concerning MPs' influences on ruminant animals, with a specific focus on the meat quality of fattening lambs.


Asunto(s)
Poliestirenos , Rumen , Animales , Ovinos , Poliestirenos/toxicidad , Enfermedades Gastrointestinales/inducido químicamente , Enfermedades Gastrointestinales/veterinaria , Inflamación/inducido químicamente , Carne , Microbioma Gastrointestinal/efectos de los fármacos , Aumento de Peso/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Microplásticos/toxicidad
3.
J Prosthet Dent ; 122(4): 383-388, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30982624

RESUMEN

STATEMENT OF PROBLEM: High rates of veneering chipping are a common prosthodontic complication of restorations with a titanium framework. A new bio high-performance polymer (BioHPP) based on polyetheretherketone (PEEK) has been introduced for denture superstructures. Clinical reports suggest that BioHPP could be used as an alternative framework material to support complete-arch restorations. However, peer-reviewed information is lacking regarding the performance of BioHPP as a framework material for implant-supported screw-retained fixed dental prostheses (FDPs) veneered with composite resin. PURPOSE: The purpose of this in vitro study was to evaluate and compare the bond strength of modified PEEK (BioHHP) and titanium with a veneering composite resin and compare the marginal fit and fracture resistance of implant-supported screw-retained FDPs fabricated by using computer-aided design and computer-aided manufacturing (CAD-CAM) frameworks veneered with composite resin. MATERIAL AND METHODS: A composite resin was bonded to 2 framework materials (n=20/group): pure titanium (Ti) and BioHPP (Bi). The shear bond strength (SBS) was determined after 24-hour wet storage. Furthermore, 20 3-unit CAD-CAM BioHPP and titanium frameworks were fabricated (n=10/group). The marginal fit between frameworks and abutments was evaluated by scanning electron microscopy by using the single-screw test. After thermocycling and mastication simulation, the fracture resistance of FDPs veneered with the composite resin was examined. The independent sample t test was used to evaluate differences (α=.05). RESULTS: Significantly higher shear bond strengths were obtained in group Bi (31.1 ±3.5 MPa) than in group Ti (20.5 ±1.8 MPa). The mean marginal gap width was 19 ±4 µm in group Bi and 16 ±6 µm in group Ti. Statistical tests showed no significant differences (P>.05). After loading, veneering chipping was observed at a load of 1960 ±233 N in group Ti. Although the BioHPP frameworks fractured at 1518 ±134 N, no chipping occurred. CONCLUSIONS: The bond strength of BioHPP with the composite resin was greater than that of titanium. CAD-CAM BioHPP frameworks exhibit good marginal fit and fracture resistance. BioHPP may be a suitable alternative to metal as a framework to be veneered with composite resin.


Asunto(s)
Prótesis Dental de Soporte Implantado , Titanio , Resinas Compuestas , Diseño Asistido por Computadora , Materiales Dentales , Porcelana Dental , Ensayo de Materiales , Polímeros , Circonio
4.
Planta ; 247(5): 1077-1087, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29350280

RESUMEN

MAIN CONCLUSION: Six types of lignin-carbohydrate complex (LCC) fractions were isolated from Eucalyptus. The acidic dioxane treatment applied significantly improved the yield of LCCs. The extraction conditions had a limited impact on the LCC structures and linkages. Characterization of the lignin-carbohydrate complex (LCC) structures and linkages promises to offer insight on plant cell wall chemistry. In this case, Eucalyptus LCCs were extracted by aqueous dioxane, and then precipitated sequentially by 70% ethanol, 100% ethanol, and acidic water (pH = 2). The composition and structure of the six LCC fractions obtained by selective precipitation were investigated by sugar analysis, molecular weight determination, and 2D HSQC NMR. It was found that the acidic (0.05-M HCl) dioxane treatment significantly improved the yield of LCCs (66.4% based on Klason lignin), which was higher than the neutral aqueous dioxane extraction, and the extraction condition showed limited impact on the LCC structures and linkages. In the fractionation process, the low-molecular-weight LCCs containing a high content of carbohydrates (60.3-63.2%) were first precipitated by 70% ethanol from the extractable solution. The phenyl glycoside (PhGlc) bonds (13.0-17.0 per 100Ar) and highly acetylated xylans were observed in the fractions recovered by the precipitation with 100% ethanol. On the other hand, such xylan-rich LCCs exhibited the highest frequency of ß-O-4 linkages. The benzyl ether (BE) bonds were only detected in the fractions obtained by acidic water precipitation.


Asunto(s)
Carbohidratos/aislamiento & purificación , Eucalyptus/metabolismo , Lignina/aislamiento & purificación , Metabolismo de los Hidratos de Carbono , Carbohidratos/química , Precipitación Química , Dioxanos/uso terapéutico , Lignina/química , Lignina/metabolismo , Espectroscopía de Resonancia Magnética , Peso Molecular
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 309: 123822, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38176193

RESUMEN

Fluoride ion is not only important for dental health, but also a contributing factor in a variety of diseases. At the same time, fluoride ions and cell viscosity are both important to the physiological environment of mitochondria. We developed a dual-response ratiometric fluorescent probe BDF based on Förster resonance energy transfer (FRET) and intramolecular charge transfer (ICT) mechanism for the detection of F- and viscosity. BDF has an outstanding intramolecular energy transfer efficiency of 97.7% and shows excellent performance for fluorine ion detection. In addition, when the system viscosity increases, the fluorescence emission intensity of BDF is greatly heightened, indicating the possibility of viscosity detection. Finally, based on the fluorescence properties of BDF, we used the probe to detect F- in the toothpaste sample and image exogenous fluoride ions in HeLa cells.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Fluoruros , Humanos , Transferencia Resonante de Energía de Fluorescencia/métodos , Colorantes Fluorescentes , Células HeLa , Flúor , Viscosidad
6.
Shanghai Kou Qiang Yi Xue ; 33(1): 64-70, 2024 Feb.
Artículo en Zh | MEDLINE | ID: mdl-38583027

RESUMEN

PURPOSE: To analyze the bone remodeling around the implant 10 years after disk-up sinus reamer(DSR)-based internal sinus floor elevation with implantation and to investigate the influence of different factors on implant retention. METHODS: The clinical and imaging data of patients undergoing DSR-based sinus floor elevation with simultaneous implantation were collected from the Department of Dental Implantology, Affiliated Hospital of Qingdao University from January 2008 to December 2011. Panoramic film and CBCT were used to measure the changes of bone mass around implant in different periods. Kaplan-Meier and Log-rank tests were used to analyze the effects of different factors on implant retention with SPSS 26.0 software package. RESULTS: The study included 98 patients with a total of 128 implants. During the follow-up of 0-168 months, 7 implants failed, and the remaining formed good osseointegration and functioned, with a 10-year cumulative retention rate of 94.53%. The height of bone formation was (0.29±0.15) mm at the top and (2.74±0.66) mm in the sinus of 75 implant sites with complete imaging data obtained ten years after surgery. Kaplan-Meier and Log-rank tests showed that 8 factors including initial bone height, elevated bone height, mucosal perforation, implant length, implant torsion, diabetes, smoking and periodontitis had significant effects on implant retention. CONCLUSIONS: The DSR-based internal sinus floor elevation with implantation is a reliable and stable bone augmentation operation for vertical bone defect in maxillary posterior region, with a 10-year cumulative retention rate of no less than 94%. Initial bone height, elevated bone height, mucosal perforation, implant length, implant torsion, diabetes, smoking and periodontitis are the important factors affecting the long-term retention rate of implants.


Asunto(s)
Implantación Dental Endoósea , Implantes Dentales , Elevación del Piso del Seno Maxilar , Humanos , Implantación Dental Endoósea/métodos , Diabetes Mellitus/cirugía , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/cirugía , Periodontitis , Resultado del Tratamiento
7.
Environ Sci Pollut Res Int ; 30(42): 95875-95891, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37561306

RESUMEN

The wastewater discharged from crude oil storage tanks (WCOST) contains high concentrations of salt and metal iron ions, and high chemical oxygen demand (COD). It belongs to "3-high" wastewater, which is difficult for purification. In this study, WCOST treatments were comparatively investigated via an advanced pretreatment and the traditional coagulation-microfiltration (CMF) processes. After WCOST was purified through the conventional CMF process, fouling occurred in the microfiltration (MF) membrane, which is rather harmful to the following reverse osmosis (RO) membrane unit, and the effluent featured high COD and UV254 values. The analysis confirmed that the MF fouling was due to the oxidation of ferrous ions, and the high COD and UV254 values were mainly attributable to the organic compounds with small molecular sizes, including aromatic-like and fulvic-like compounds. After the pretreatment of the advanced process consisting of aeration, manganese sand filtration, and activated carbon adsorption in combination with CMF process, the removal efficiencies of organic matter and total iron ions reached 97.3% and 99.8%, respectively. All the water indexes of the effluent, after treatment by the advanced multi-unit process, meet well the corresponding standard. The advanced pretreatment process reported herein displayed a great potential for alleviating the MF membrane fouling and enhanced the lifetime of the RO membrane system in the 3-high WCOST treatment.


Asunto(s)
Petróleo , Purificación del Agua , Aguas Residuales , Eliminación de Residuos Líquidos , Petróleo/análisis , Filtración , Iones/análisis , Hierro/análisis , Ósmosis , Membranas Artificiales
8.
Sci Rep ; 12(1): 10797, 2022 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-35750776

RESUMEN

Screw loosening is one of the most common clinical problems of dental implants. Research on the influencing factors of screw loosening is very important to prevent screw loosening. The purpose of this in vitro study was to evaluate the influence of liquid contamination on the screw loosening. According to the contamination condition, forty-five abutment screws were divided into three groups (n = 15): no contamination, artificial saliva contamination, and mouthwash contamination. The preload and friction coefficient of the abutment screws were recorded. Then, the reverse torque values (RTVs) and settlement were measured after 3.0 × 105 and 6.0 × 105 cycles. The surface wear of the screws was analyzed. Finally, the stress distribution of the abutment screws was calculated by finite element analysis (FEA). The results showed that fluid contamination reduced the friction coefficient, increased the preload, decrease the settlement, improved resistance to screw loosening, and reduced wear on the thread surface. Appropriate antimicrobial lubrication may improve the anti-loosening performance of abutment screws and prevent excessive wear on the threaded surface.


Asunto(s)
Tornillos Óseos , Implantes Dentales , Análisis de Elementos Finitos , Fricción , Lubrificación , Torque
9.
J Biomed Nanotechnol ; 18(3): 860-867, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35715922

RESUMEN

Fragrances have many biological activities such as anti-anxiety, anti-depression, and improving cognitive memory. However, most fragrances are so volatile that the useful lifespan of the fragrances is very short and excessive fragrance concentration makes us uncomfortable. In this study, dual pH and temperature-sensitive nanogels named EG@CPMONGs were prepared to encapsulate eugenol. This nano-fragrance was then applied to silk. In the following, the effects of EG@CPMO-NGs on the regulation of central nervous systems were evaluated. Open-field tests showed that EG@CPMONGs had an obvious effect on stress relief. Elevated plus-maze tests proved the significant effect of EG@CPMO-NGs on anti-anxiety. Morris water maze tests demonstrated the positive impact of nano-fragrance on spatial learning and memory. Therefore, these dual pH and temperature-sensitive nanogels loaded with eugenol had significant and positive effects on the central nervous system.


Asunto(s)
Eugenol , Perfumes , Sistema Nervioso Central , Concentración de Iones de Hidrógeno , Nanogeles , Temperatura
10.
Sci Rep ; 12(1): 11441, 2022 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-35794199

RESUMEN

With the serious shortage of water resources and the development of water-saving agriculture, the application of drip irrigation has been paid more and more attention. But there was lack of oat planting methods suitable for drip irrigation, currently. In order to establish an efficient oat planting method for drip irrigation, a study was conducted at Agriculture and Forestry Sciences of Ulanqab, Inner Mongolia during the season (2019-2020) to evaluate the effect of strip cropping with reducing row spacing and super absorbent polymer on the yield and water use efficiency of oat. To conduct the field trials, a split plot system in three replications was established. Three planting patterns were in the main plots, including conventional cropping with 20 cm equal row spacing (PA), strip cropping with the 15 cm row spacing (PB) and strip cropping with the 10 cm row spacing (PC), and two super absorbent polymer levels were in the subplots, including 22.5 kg ha-2 (Y) and 0 (N). The results showed that, compared with PA, PB and PC both decreased the irrigation volumes by 4.5-18.4 mm, and the irrigation volumes of PB was lower than that of PC. When super absorbent polymers were applied, compared with PA, PB significantly increased grain yield and above-ground biomass, but PC had the opposite effects. The grain yield and above-ground biomass of PB significantly increased by 16.65% and 7.31% on average in two years, respectively. And the increasing of grain yield was attributed by the significant increasing of pike number and kernel number per spike. But when super absorbent polymers were not applied, PB had no significant effects on grain yield and above-ground biomass. PB also had the significant effects on regulating water use of oats weather or not super absorbent polymers were applied, it significantly increased the precipitation ratio by 2.64% (PBY) and 2.13% (PBN) and decreased irrigation ration by 3.32% (PBY) and 5.28% (PBN) on average in two years. Although PB and PC both decreased the total evapotranspiration, but PB increased WUE and PC deceased WUE. The WUE of PB increased by 19.70% (PBY) and 9.87% (PBN) on average in two years. Also PB had the highest economic benefits in all treatments. In conclusion, a drip irrigation oat planting pattern was proposed, which the row spacing is 15 cm, adjusted the equal row spacing planting to 8-row strip planting, with a belt spacing of 30 cm, combined with the application of 22.5 kg ha-2 applying super absorbent polymers. And this oat planting pattern is a viable strategy to improve oat productivity.


Asunto(s)
Avena , Agua , Agricultura/métodos , Grano Comestible , Polímeros
11.
Medicine (Baltimore) ; 100(7): e24855, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33607859

RESUMEN

BACKGROUND: To analyze the prevalence of latent infection of pathogens of hand, foot, and mouth disease (HFMD) in Chinese healthy population and its influencing factors, so as to provide reference for the prevention and control of HFMD. METHODS: A systematic literature searching about the incidence of latent infection of HFMD was conducted in Chinese and English databases. The inclusion and exclusion criteria of the retrieved literature were established. The qualified literatures were screened and the data were extracted. The pooled rate and its 95% confidence interval was used to assess the latent infection rate of HFMD pathogens in healthy Chinese population, and subgroup analysis was conducted based on gender and age. All statistical analyses were performed using the STATA version 12.0 software. RESULTS: A total of 31 literatures were included in this meta-analysis. The recessive infection rate of HFMD pathogens reported in the literature of Chinese healthy people ranged from 4.59% to 44.12%. The results of meta-analysis showed that the latent infection rate of human enteroviruses (HEVs) in healthy Chinese population was 17.5% (14.9-20.1%), among which, the latent infection rates of EV-A71, CV-A16, and other HEVs were 3.3% (2.2-4.4%), 1.7% (1.0-2.5%), and 15.1% (11.1-17.1%), respectively. The latent infection rates of HEVs in healthy men and women in China were 16.7% (12.9-20.4%) and 14.4% (10.8-18.0%), respectively. The latent infection rates of HEVs in the healthy population aged 0 to 5 years and over 5 years were 24.4% (20.4-28.5%) and 9.4% (6.5-12.2%), respectively. Meta regression showed that the factors affecting the latent infection rate of HEVs in Chinese healthy population included sampling period, sampling area, and study population. CONCLUSION: The latent infection rate of HEVs is high in healthy people in China, but it is mainly caused by other enteroviruses. The latent infection rate of HEVs in male was higher than that of female and was greater in people aged 0 to 5 than that of aged over 5 years. Limited by the quantity and quality of the included studies, more high-quality studies are needed for further verification in the future.


Asunto(s)
Infecciones Asintomáticas/epidemiología , Enfermedad de Boca, Mano y Pie/epidemiología , Voluntarios Sanos/estadística & datos numéricos , Infección Latente/epidemiología , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Preescolar , China/epidemiología , Estudios Transversales , Manejo de Datos , Enterovirus/genética , Enterovirus/aislamiento & purificación , Enterovirus/patogenicidad , Enterovirus Humano A/genética , Enterovirus Humano A/aislamiento & purificación , Enterovirus Humano A/patogenicidad , Infecciones por Enterovirus/epidemiología , Infecciones por Enterovirus/virología , Femenino , Enfermedad de Boca, Mano y Pie/prevención & control , Humanos , Incidencia , Lactante , Recién Nacido , Infección Latente/virología , Masculino , Prevalencia , Adulto Joven
12.
J Sep Sci ; 33(15): 2278-86, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20589777

RESUMEN

The enrichment and separation of astragalosides I-IV (AGs I-IV) were studied on eight macroporous resins in the present study. SA-3 resin offered the best adsorption and desorption capacities for AGs I-IV than other resins. The models of adsorption kinetics were investigated in order to elucidate the mechanism of adsorption. The pseudo-second-order model was the better choice than the pseudo-first-order model to describe the adsorption behavior of AGs I-IV onto SA-3 resin. The equilibrium experimental data were well fitted to Langmuir and Freundlich isotherms. SA-3 resin adsorption chromatography tests were carried out to optimize the separation process of AGs I-IV from Radix Astragali extracts. With the optimum parameters for adsorption and desorption, the contents of AGs I-IV were 8.78-, 11.60-, 10.52- and 11.28-fold increased with the recovery yields being 65.88, 90.92, 84.25 and 94.17%, respectively. The preparative enrichment and separation of AGs I-IV from Radix Astragali extracts can be easily and effectively achieved by SA-3 resin adsorption chromatography. The developed methodology can also be referenced for the separation of other active constituents from herbal materials and manufacture of Radix Astragali products.


Asunto(s)
Planta del Astrágalo/química , Extractos Vegetales/química , Resinas Sintéticas/química , Saponinas/aislamiento & purificación , Triterpenos/aislamiento & purificación , Adsorción , Cromatografía , Porosidad
13.
J Invest Surg ; 33(6): 520-529, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30644766

RESUMEN

Objective: The disk-up sinus reamer (DSR) is a modified instrument used to elevate the maxillary sinus floor. This study aimed to compare the effects of modified DSR sinus floor elevation (DSFE) with osteotome sinus floor elevation (OSFE), both with simultaneous implant placement. Methods: Twelve miniature pigs were treated with DSFE on one side and OSFE on the other. Implants 9 mm in length were placed in six pigs without grafting, while implants 11 mm in length were placed in the other six pigs with grafting. After submerged healing for 3 months, vertical bone gain (VBG), general and histological observation, and bone contact ratio (BCR) were analyzed. Results: The mean maxillary residual bone height (RBH) when implants were placed was 6.45 ± 0.36 mm. In the no-grafting group, DSFE and OSFE had a similar VBG after 3 months. The grafting group with DSFE recorded a significantly higher VBG (VBG0: 7.83 ± 0.44 mm, VBG1: 7.54 ± 0.40 mm) than the graft group with OSFE (VBG0: 5.45 ± 0.56 mm, VBG1: 4.34 ± 2.15 mm) (p < 0.05). One implant became loose and the sinus mucosa of three pigs appeared metallic in color on the control side (OSFE). Conclusions: The effect of OSFE and DSFE is similar when there is no need for grafting. DSFE seems a better alternative method for sinus floor elevation with grafting when more VBG is needed.


Asunto(s)
Injerto de Hueso Alveolar/métodos , Implantación Dental Endoósea/instrumentación , Seno Maxilar/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Elevación del Piso del Seno Maxilar/instrumentación , Animales , Implantación Dental Endoósea/métodos , Implantes Dentales , Femenino , Modelos Animales , Elevación del Piso del Seno Maxilar/métodos , Porcinos , Porcinos Enanos
14.
Carbohydr Polym ; 238: 116212, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-32299557

RESUMEN

In this study, the cellulose and hemicelluloses in heartwood, sapwood, and bark of E. urophylla × E. grandis were comprehensively investigated. The ultrastructural topochemistry of carbohydrates in cell walls was examined in situ by confocal Raman microscopy. Cellulose and alkali-extractable hemicelluloses samples were isolated from different tissues and comparatively characterized by compositional carbohydrate analyses, determination of molecular weights, FT-IR spectroscopy, and XRD and NMR techniques. It was found that among all of the samples, heartwood cellulose had the highest molecular weight as well as the lowest degree of crystallinity. Meanwhile the hemicelluloses in heartwood had higher xylose content, lower degree of branching, slightly lower molecular weights but narrower polydispersity than those in sapwood. The eucalyptus hemicelluloses mainly consisted of (1→4)-ß-D-xylan backbone with glucuronic acid side chains. Furthermore, the hemicelluloses isolated from sapwood had a higher degree of substitution with terminal galactose than those isolated from heartwood and bark.


Asunto(s)
Pared Celular/química , Celulosa/química , Eucalyptus/química , Corteza de la Planta/química , Polisacáridos/química , Madera/química
15.
Shanghai Kou Qiang Yi Xue ; 28(2): 148-153, 2019.
Artículo en Zh | MEDLINE | ID: mdl-31384899

RESUMEN

PURPOSE: To compare the short-term clinical effect and to assess the influencial factors of immediate implant placement and delayed implant placement around single-tooth implant in the aesthetic area. METHODS: A total of 114 patients requiring a single-tooth implant in the aesthetic area were reviewed at Center for Implant Dentistry of Stomatological Hospital of China Medical University. They were divided into immediate implant group and delayed implant group. The patients were followed up for 1 year after upper structure rehabilitation, and the pink esthetic score and the marginal bone absorption around the implants were measured. Statistical analysis was performed using SPSS 17.0 software package. RESULTS: After 1 year of upper structure rehabilitation, 114 implants were stable and the marginal bone absorption around the implants of the immediate implant group was (0.36±0.39) mm,significantly smaller than the delayed implant group [(0.79±0.67)mm, P<0.001]. The difference in PES score between the two groups were not statistically significant on the day of rehabilitation and 1 year after upper structure rehabilitation(P>0.05). Significant improvement of PES on the day of rehabilitation and 1 year after upper structure rehabilitation and marginal bone absorption was found with flapless surgery. SLA and DAE surface treatment methods had no significant impact on PES and marginal bone absorption (P>0.05). Graft procedure had an unfavorable effect on PES value both on the day of rehabilitation and 1 year after upper structure rehabilitation. CONCLUSIONS: Under appropriate indications, immediate implant placement and immediate repair could reduce the time of missing teeth. The marginal bone absorption of immediate implant group is smaller than delayed implant group. Flapless surgery avoids damage to gingival tissue, reduces postoperative reaction and improves the aesthetic outcomes after repair.


Asunto(s)
Implantes Dentales de Diente Único , Estética Dental , Carga Inmediata del Implante Dental , Alveolo Dental , China , Implantación Dental Endoósea , Humanos , Extracción Dental , Resultado del Tratamiento
16.
J Agric Food Chem ; 67(3): 968-974, 2019 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-30580517

RESUMEN

In the present study, lignin from eucalyptus was extracted with 80% alkaline dioxane (0.05 M NaOH) from ball-milled wood and subsequently fractionated by gradient acid precipitation from the filtrate. Meanwhile, the residual lignin was prepared by a double enzymatic hydrolysis process. The yield of the lignin extracted by alkaline dioxane (LA-2) was 29.5%. The carbohydrate contents and molecular weights of the gradient acid precipitated lignin fractions gradually decreased from 4.90 to 1.36% and from 7770 to 5510 g/mol, respectively, with the decline of the pH value from 6 to 2. Results from two-dimensional heteronuclear single quantum coherence nuclear magnetic resonance (NMR) and 31P NMR spectroscopy showed an evident reduction of ß- O-4 ' linkages with the pH value decrease, while the contents of aliphatic -OH, phenolic -OH, and carboxylic groups displayed an increasing trend. Moreover, the residual lignin exhibited the highest molecular weight (11690 g/mol), the most abundant ß- O-4 ' linkages (71.1%), and the highest S/G ratio (4.68).


Asunto(s)
Eucalyptus/química , Lignina/química , Extractos Vegetales/química , Álcalis/química , Dioxanos/química , Concentración de Iones de Hidrógeno , Hidrólisis , Lignina/aislamiento & purificación , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Extractos Vegetales/aislamiento & purificación , Madera/química
17.
Int J Oral Maxillofac Implants ; 33(2): 298­310, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29420672

RESUMEN

PURPOSE: The aim of this study was to confirm the in vivo effect of surface-modified titanium (Ti) implants with zinc (Zn) prepared by a plasma electrolytic oxidation (PEO) method on the process of osseointegration. MATERIALS AND METHODS: Forty-five New Zealand white rabbits were used. Implants were divided into three groups due to different surface treatments (the PEO-Zn group, the PEO-calcium phosphorus [Ca/P] group, and the sandblasted [control] group) and were randomly inserted into rabbits' mandibles. The implant surface morphology and chemical state of the relevant elements were observed. The maximum push-out force, the bone-to-implant contact (BIC), and the mineral apposition ratio (MAR) were detected at 4, 8, and 12 weeks after implantation. RESULTS: A two-layer structure, with a dense inner layer and a porous outer layer, was found in the PEO samples. In the PEO-Zn group, CaHPO4·2H2O (dicalcium phosphate dihydrate) was the main calcium compound, and ZnO was identified as the predominant form of Zn. More bone deposition was found on the top of the PEO-Zn implant, which was also confirmed by scanning electron microscope (SEM) afterward, and the shear strength reached a maximum value of 1.57 ± 0.26 MPa at 12 weeks compared with the sandblasted group and the PEO-Ca/P group. The BIC values and the MARs of the PEO-Zn group were significantly higher than the control group, especially at the early weeks (P < .05), and first reached maximum values of 73.91% ± 9.01% and 4.89 ± 0.60 µm/d at 12 weeks, respectively. CONCLUSION: Implants with Zn coating by the PEO method could accelerate bone formation and bone remodeling, shorten the osseointegration period, and enhance bone-implant bonding force.


Asunto(s)
Materiales Biocompatibles Revestidos/química , Implantes Dentales , Oseointegración/fisiología , Titanio , Zinc/química , Animales , Microscopía Electrónica de Rastreo , Osteogénesis , Oxidación-Reducción , Porosidad , Prótesis e Implantes , Conejos , Propiedades de Superficie
18.
Int J Biol Macromol ; 106: 885-892, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28830775

RESUMEN

A better understanding of the lignin in the straw of rapeseed, Brassica campestris L., is a prerequisite for promoting the biorefinery industry of rapeseed. Two different methods for fractionating lignin from rapeseed straw were proposed in this study. Lignin in the raw material was isolated with alkaline solution and recovered by acid precipitation. A comparison between two lignin preparations obtained from two different methods has been made in terms of yield and purity. The structural features were investigated by gel permeation chromatography, FT-IR spectroscopy, 2D-HSQC NMR and 31P NMR. Taking into consideration of the yield and purity, the proposed methods are effective for extracting lignin. NMR results showed that syringyl (S) was the predominant unit over guaiacyl (G) or p-hydroxyphenyl (H) units in the lignin preparations, and linkages ß-O-4', ß-ß' and ß-5' were also identified and quantified by NMR techniques. This study demonstrated that the combination of hydrothermal or dilute-acid pretreatment and alkaline process could efficiently isolate the lignins from the rapeseed straw to further applications for industries. It was found that the enzymatic hydrolysis of the two-step pretreated rapeseed straw increased 5.9 times than the straw without treatment, which is benefit for bioethanol production from rapeseed straw.


Asunto(s)
Brassica rapa/química , Fraccionamiento Químico/métodos , Etanol/química , Lignina/química , Ácidos/química , Álcalis/química , Biomasa , Hidrólisis , Lignina/aislamiento & purificación , Estructura Molecular , Tallos de la Planta/química , Espectroscopía Infrarroja por Transformada de Fourier
19.
Bioresour Technol ; 225: 127-133, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27888729

RESUMEN

The aim of the research was to evaluate the effect of combined treatments on fermentable sugar production from rapeseed straw. An optimum condition was found to be the combination of hydrothermal pretreatment at 180°C for 45min and post-treatment by 2% NaOH at 100°C for 2h, which was based on the quantity of monosaccharides released during enzymatic hydrolysis. As compared with the raw material without treatment, the combination of hydrothermal pretreatment and alkali post-treatment resulted in a significant increase of the saccharification rate by 5.9times. This process potentially turned rapeseed straw into value added products in accordance with the biorefinery concept.


Asunto(s)
Biotecnología/métodos , Brassica rapa/química , Fraccionamiento Químico/métodos , Biomasa , Celulasas/química , Celulasas/metabolismo , Celulosa/química , Celulosa/aislamiento & purificación , Glucosa/química , Hidrólisis , Lignina/química , Lignina/aislamiento & purificación , Brotes de la Planta/química , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Hidróxido de Sodio/química , Temperatura , beta-Glucosidasa/química , beta-Glucosidasa/metabolismo
20.
ACS Appl Mater Interfaces ; 8(15): 10014-28, 2016 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-27022831

RESUMEN

Manipulating the degradation rate of biomedical magnesium alloys poses a challenge. The characteristics of a microarc oxidation (MAO), prepared in phytic acid, and poly(L-lactic acid) (PLLA) composite coating, fabricated on a novel Mg-1Li-1Ca alloy, were studied through field emission scanning electron microscopy (FE-SEM), electron probe X-ray microanalysis (EPMA), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The corrosion behaviors of the samples were evaluated via hydrogen evolution, potentiodynamic polarization and electrochemical impedance spectroscopy in Hanks' solution. The results indicated that the MAO/PLLA composite coatings significantly enhanced the corrosion resistance of the Mg-1Li-1Ca alloy. MTT and ALP assays using MC3T3 osteoblasts indicated that the MAO/PLLA coatings greatly improved the cytocompatibility, and the morphology of the cells cultured on different samples exhibited good adhesion. Hemolysis tests showed that the composite coatings endowed the Mg-1Li-1Ca alloys with a low hemolysis ratio. The increased solution pH resulting from the corrosion of magnesium could be tailored by the degradation of PLLA. The degradation mechanism of the composite coatings was discussed. The MAO/PLLA composite coating may be appropriate for applications on degradable Mg-based orthopedic implants.


Asunto(s)
Aleaciones/farmacología , Materiales Biocompatibles Revestidos/farmacología , Ortopedia , Poliésteres/farmacología , Prótesis e Implantes , Animales , Calcio/farmacología , Muerte Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Corrosión , Electroquímica , Hemólisis/efectos de los fármacos , Hidrógeno/análisis , Concentración de Iones de Hidrógeno , Litio/farmacología , Magnesio/farmacología , Ratones , Oxidación-Reducción , Conejos , Espectrometría por Rayos X
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA