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1.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(5): 899-909, 2023 Oct 18.
Artículo en Zh | MEDLINE | ID: mdl-37807746

RESUMEN

OBJECTIVE: To compare and analyze the feasibility of autologous facet joint bone block as an alternative to polyetheretherketone (PEEK) cage in lumbar intervertebral fusion surgery for patients with osteoporosis. METHODS: From December 2018 to June 2021, the case data of patients with osteoporosis (T value ≤ -2.5 on dual energy X-ray bone density) who underwent posterior lumbar interbody fusion in the Fourth Medical Center, Chinese PLA General Hospital were retrospectively reviewed. All the cases were followed up for no less than 12 months and were divided into two groups according to the differences of interbody fusion materials: the autologous facet joint bone block group (autogenous bone group) and the PEEK cage group (PEEK group). The general data [such as age, gender, body mass index (BMI), primary diagnosis, distribution of fusion segments, bone mineral density of lumbar (BMD), incidence of preoperative complications], the perioperative data (such as duration of operation, intraoperative blood loss, postoperative drainage, perioperative allogeneic blood transfusion rate), and the incidence of postoperative complications were compared between the two groups. Imaging parameters (disc height, lumbar lordosis angle, segment lordosis angle, segmental lordosis angle, disc height improvement rate, and fusion rate) and lumbar functional scores [visual analogue scale (VAS), Oswestry disability index (ODI), Japanese Orthopedics Association (JOA) score for lower back pain] were compared to evaluate the clinical efficacy between the kinds of intervertebral fusion materials 1 week, 3 months and 6 months postoperative and at the last follow-up. RESULTS: A total of 118 patients were enrolled, including 68 cases in the autogenous bone group and 50 cases in the PEEK group, there were no statistical differences in age, gender, BMI, primary diagnosis, distribution of fusion segments, BMD, incidence of preoperative complications, duration of operation, intraoperative blood loss, postoperative drainage, perioperative allogeneic blood transfusion rate, incidence of postoperative complications, all the preoperative imaging parameters and all the lumbar function scores between the two groups (P>0.05). Postoperative superficial surgical site infections occurred in 3 patients in the autogenous bone group and 2 patients in the PEEK group. At the last follow-up, 3 cases of intervertebral graft collapse occurred in the autogenous bone group and 5 cases in the PEEK group, 1 case of graft subsidence in the autogenous bone group and 1 case in the PEEK group. All the imaging parameters showed significant differences between postoperation and preoperation (P < 0.05), and all the imaging parameters showed significant differences between 1 week and 3 months postoperative in both groups (P < 0.05). The height, angle of fusion gap in the autogenous bone group were lower than those in the PEEK group 1 week postoperatively (P < 0.05), and the fusion gap height improvement rate in the autogenous bone group was lower than that in the PEEK group (P < 0.05). The cases in both groups started to show final fusion 3 months after surgery, and the fusion rate in the autogenous bone group was 75% 6 months postoperatively, which was significantly higher than the rate of 56% in the PEEK group (P < 0.05), and there was no statistically significant difference in the final fusion rate between the two groups (P>0.05). The ODI, the postoperative VAS score was significantly lower than that in preoperation, while the postoperative JOA score was significantly higher than that in preoperation (P < 0.05). The ODI was lower while the JOA score was higher of the autogenous bone group than that of the PEEK group 6 months postoperatively (P < 0.05). CONCLUSION: In osteoporosis patients, good interbody fusion rate and improvement of lumbar vertebral function can be obtained by using autologous facet joint bone block or PEEK cage, while the fusion rate and the improvement of lumbar function with autologous facet joint bone block are better than those with PEEK cage 6 months post-operatively. PEEK cage is superior to autologous facet joint bone block in intervertebral distraction and improvement of lumbar lordosis. Significant disc space subsidence occurred in osteoporotic patients within 3 months after lumbar interbody fusion, and the subsidence of PEEK cage was more obvious than that of autologous facet joint bone block.


Asunto(s)
Lordosis , Osteoporosis , Fusión Vertebral , Articulación Cigapofisaria , Humanos , Estudios Retrospectivos , Fusión Vertebral/métodos , Polietilenglicoles/uso terapéutico , Resultado del Tratamiento , Cetonas , Vértebras Lumbares/cirugía , Pérdida de Sangre Quirúrgica , Complicaciones Posoperatorias , Hemorragia Posoperatoria
2.
Clin Oral Investig ; 26(1): 969-979, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34363102

RESUMEN

OBJECTIVE: In the present study, we intend to assess the function of Sema3A in osteointegration of titanium implants both in vivo and in vitro. MATERIAL AND METHODS: Briefly, Sema3A was transfected in HBMSCs cells to detect its effect on osteogenesis. Subsequently, an in vivo rabbit model was established. Eighteen female rabbits were randomly assigned into three groups (n=6), and rabbits in the two treatment groups (OVX groups) were subjected to bilateral ovariectomy, while those in the control group were treated with sham operation. Twelve weeks later, we first examined expression levels of Sema3A in rabbits of the three groups. Titanium implants were implanted in rabbit proximal tibia. Specifically, rabbits in sham group were implanted with Matrigel, while the remaining in the OVX experimental group (OVX+Sema3A group) and OVX group were implanted with Matrigel containing Sema3A adeno-associated virus or empty vector, respectively. RESULTS: Histomorphometry results uncovered that rabbits in the OVX+Sema3A group had a significantly higher BIC compared with those of the OVX group on the 12th week of post-implantation. And compared with the OVX group, the maximum push-out force increased by 89.4%, and the stiffness increased by 39.4%, the toughness increased by 63.8% in the OVX+Sema3A group at 12 weeks. CONCLUSION: Sema3A has a positive effect on promoting early osseointegration of titanium implants in osteoporotic rabbits. CLINICAL RELEVANCE: Our research found that Sema3A can improve the osteogenic ability of bone marrow stem cells and promotes osseointegration during osteoporosis.


Asunto(s)
Implantes Dentales , Osteoporosis , Animales , Femenino , Conejos , Oseointegración , Osteoporosis/cirugía , Ovariectomía , Tibia , Titanio
3.
Sensors (Basel) ; 21(24)2021 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-34960403

RESUMEN

Stress affects the microstructure of the material to influence the durability and service life of the components. However, the previous work of stress measurement lacks quantification of the different variations in time and spatial features of micromagnetic properties affected by stress in elastic and plastic ranges, as well as the evolution of microstructure. In this paper, microstructure evolution under stress in elastic and plastic ranges is evaluated by magnetic Barkhausen noise (MBN) transient analysis. Based on a J-A model, the duration and the intensity are the eigenvalues for MBN transient analysis to quantify transient size and number of Barkhausen events under stress. With the observation of domain wall (DW) distribution and microstructure, the correlation between material microstructure and MBN transient eigenvalues is investigated to verify the ability of material status evaluation on the microscopic scale of the method. The results show that the duration and the intensity have different change trends in elastic and plastic ranges. The eigenvalue fusion of the duration and intensity distinguishes the change in microstructure under the stress in elastic and plastic deformation. The appearance of grain boundary (GB) migration and dislocation under the stress in the plastic range makes the duration and the intensity higher on the GB than those inside the grain. Besides, the reproducibility of the proposed method is investigated by evaluating microstructure evolution for silicon steel sheet and Q235 steel sheet. The proposed method investigates the correlation between the microstructure and transient micromagnetic properties, which has the potential for stress evaluation in elastic and plastic ranges for industrial materials.


Asunto(s)
Plásticos , Acero , Fenómenos Magnéticos , Magnetismo , Reproducibilidad de los Resultados
4.
Environ Sci Technol ; 53(6): 3238-3249, 2019 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-30768244

RESUMEN

Flow-through configuration for electrochemical disinfection is considered as a promising approach to minimize the formation of toxic byproducts and energy consumption via the enhanced convective mass transport as compared with conventional flow-by one. Under this hydrodynamic condition, it is essential to ascertain the effect of sequential electro-redox processes with the cathode/anode then anode/cathode arrangements on disinfection performance. Here, carbon fiber felt (CFF) was utilized to construct two flow-through electrode systems (FESs) with sequential reduction-oxidation (cathode-anode) or oxidation-reduction (anode-cathode) processes to systematically compare their disinfection performance toward a model Escherichia coli ( E. coli) pathogen. In-situ sampling and live/dead backlight staining experiments revealed that E. coli inactivation mainly occurred on anode via an adsorption-inactivation-desorption process. In reduction-oxidation system, after the cathode-pretreatment, bulk solution pH increased significantly, leading to the negative charge of E. coli cells. Hence, E. coli cells were adsorbed and inactivated easily on the subsequent anode, finally resulting in its much better disinfection performance and energy efficiency than the oxidation-reduction system. Application of 3.0 V resulted in ∼6.5 log E. coli removal at 1500 L m-2 h-1 (50 mL min-1), suggesting that portable devices can be designed from CFF-based FES with potential application for point-of-use water disinfection.


Asunto(s)
Desinfección , Agua , Fibra de Carbono , Técnicas Electroquímicas , Electrodos , Escherichia coli , Oxidación-Reducción
5.
Macromol Rapid Commun ; 38(19)2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28804973

RESUMEN

The preparation of well-defined block copolymers using controlled radical polymerization depends on the proper order of monomer addition. The reversed order of monomer addition results in a mixture of block copolymer and homopolymer and thus has typically been avoided. In this paper, the low blocking efficiency of reversed monomer addition order is utilized in combination with surface initiated reversible addition-fragmentation chain-transfer polymerization to establish a facile procedure toward mixed polymer brush grafted nanoparticles SiO2 -g-(PS (polystyrene), PS-b-PMAA (polymethacrylic acid)). The SiO2 -g-(PS, PS-b-PMAA) nanoparticles are analyzed by gel permeation chromatography deconvolution, and the fraction of each polymer component is calculated. Additionally, the SiO2 -g-(PS, PS-b-PMAA) are amphiphilic in nature and show unique self-assembly behavior in water.


Asunto(s)
Nanopartículas/química , Polímeros/química , Poliestirenos/química , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Metacrilatos/síntesis química , Metacrilatos/química , Metacrilatos/uso terapéutico , Polimerizacion , Polímeros/síntesis química , Poliestirenos/síntesis química , Poliestirenos/uso terapéutico , Dióxido de Silicio/síntesis química , Dióxido de Silicio/química , Dióxido de Silicio/uso terapéutico , Propiedades de Superficie , Agua/química
6.
Am J Physiol Heart Circ Physiol ; 311(4): H1051-H1062, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-27591219

RESUMEN

The bacterial endotoxin lipopolysaccharide (LPS) is a main culprit responsible for cardiac dysfunction in sepsis. This study examined whether resveratrol could protect against LPS-induced cardiac dysfunction by improving the sarcoplasmic endoplasmic reticulum Ca2+-ATPase (SERCA2a) activity. Echocardiographic parameters, cardiomyocyte contractile and Ca2+ transient properties, markers for cardiac inflammation, cell death, and oxidative stress, SERCA2a activity, and the ratios of phospholamban (PLB) monomer to oligomer were measured. Cardiac function was decreased >50% after LPS challenge (6 mg/kg for 6 h), which was improved by resveratrol. There was neither difference in plasma tumor necrosis factor-α and troponin I levels nor in infiltration of CD45+ cells in cardiac tissue between resveratrol-treated and untreated groups. In cardiomyocytes, LPS significantly decreased contractile amplitude, elongated relengthening time, diminished Ca2+ transient, reduced SERCA2a activity, and increased superoxide generation. These pathological alterations were attenuated by resveratrol treatment. Immunoblot analysis showed that LPS-treated mice had increased levels of malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), and the monomer form of PLB, along with decreases in the levels of SERCA2a, the oligomer form of PLB and nuclear factor erythroid 2-related factor (Nrf-2). Resveratrol treatment upregulated SERCA2a, the oligomer form of PLB, and Nrf-2 expression and function, and downregulated MDA, 4-HNE, and the monomer form of PLB. Our data suggest that the activity of SERCA2a in endotoxemia is inhibited, possibly due to increases in the monomer form of PLB. Resveratrol protects the heart from LPS-induced injuries at least in part through promoting the oligomerization of PLB that leads to enhanced SERCA2a activity.


Asunto(s)
Antioxidantes/farmacología , Proteínas de Unión al Calcio/efectos de los fármacos , Corazón/efectos de los fármacos , Lipopolisacáridos/farmacología , Contracción Miocárdica/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/efectos de los fármacos , Estilbenos/farmacología , Aldehídos/metabolismo , Animales , Western Blotting , Calcio/metabolismo , Proteínas de Unión al Calcio/metabolismo , Regulación hacia Abajo , Immunoblotting , Masculino , Malondialdehído/metabolismo , Ratones , Ratones Endogámicos C57BL , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Factor 2 Relacionado con NF-E2/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo/efectos de los fármacos , Polímeros/metabolismo , Resveratrol , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Superóxidos/metabolismo , Troponina I/efectos de los fármacos , Troponina I/metabolismo , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia Arriba
7.
Analyst ; 140(18): 6250-3, 2015 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-26280030

RESUMEN

Multiple layers of polyvinyl alcohol (PVA) coating are generated onto silica gel by thermal immobilization to form a stationary phase applied for hydrophilic interaction liquid chromatography (HILIC). It offers an easy way to manipulate the thickness of PVA coating and the obtained stationary phase demonstrated high efficiency and high chemical stability.


Asunto(s)
Cromatografía Liquida/métodos , Interacciones Hidrofóbicas e Hidrofílicas , Alcohol Polivinílico/química , Gel de Sílice/química
8.
Opt Lett ; 39(8): 2378-81, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24978997

RESUMEN

We demonstrated amplified spontaneous emission by embedding dye molecules within a dielectric layer of a metal-dielectric-metal subwavelength structure. It was reinforced when a strong coupling occurred between the Fabry-Perot mode supported by the dielectric layer and the surface plasmon polariton mode supported by the adjacent metallic grating. Here, we adjust the two mode interaction via tuning the depth of the metallic grating grooves. The stronger the interaction, the smaller the full width at half-maximum of the emission spectra and the lower the threshold of the amplified spontaneous emission.


Asunto(s)
Resonancia por Plasmón de Superficie/instrumentación , Colorantes Fluorescentes , Microtecnología , Fenómenos Ópticos , Polimetil Metacrilato , Plata , Espectrometría de Fluorescencia
9.
J Hazard Mater ; 476: 135100, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38972200

RESUMEN

This research proposes a simple and novel strategy for the green detection of antibiotics along with the reduction of microplastic and humic acid (HA) hazards. The entire process is based on a single-step solvent-sieving method to separate HA into insoluble (IHA) and soluble (SHA) components, subsequently recombining and designing the application according to the original characteristics of selected fractions in accordance with the zero-waste principle. IHA was applied as a dispersive solid phase extraction (DSPE) sorbent without chemical modification for the enrichment of trace MACs in complex biological matrices. The recovery of MACs was 74.06-100.84 % in the range of 2.5-1000 µg∙kg-1. Furthermore, SHA could be combined with biodegradable polyvinyl alcohol (PVA) to prepare multifunctional composite films. SHA endows the PVA film with favorable mechanical properties, excellent UV shielding as well as oxidation resistance performance. Compared with pure PVA, the tensile strength, toughness, antioxidant and UV-protection properties were increased to 157.3 Mpa, 258.6 MJ·m-3, 78.6 % and 60 % respectively. This study achieved a green and economically valuable utilization of all components of waste HA, introduced a novel approach for monitoring and controlling harmful substances and reducing white pollution. This has significant implications for promoting sustainable development and recovering valuable resources.


Asunto(s)
Antibacterianos , Sustancias Húmicas , Alcohol Polivinílico , Sustancias Húmicas/análisis , Antibacterianos/química , Antibacterianos/análisis , Alcohol Polivinílico/química , Extracción en Fase Sólida/métodos , Tecnología Química Verde , Resistencia a la Tracción
10.
Zhongguo Zhong Yao Za Zhi ; 38(7): 995-9, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23847944

RESUMEN

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


Asunto(s)
Aconitina/química , Aconitum/química , Alcaloides/química , Medicamentos Herbarios Chinos/química , Aconitina/aislamiento & purificación , Adsorción , Alcaloides/aislamiento & purificación , China , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/aislamiento & purificación , Porosidad , Resinas Sintéticas/química
11.
Front Pediatr ; 11: 1163368, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37576136

RESUMEN

Objective: This study aimed to retrospectively describe the unplanned retreatment of dental general anesthesia (DGA) in children with severe early childhood caries (S-ECC) and explore potential factors that may influence the outcome of DGA treatment. Methods: Medical records of children with S-ECC who received DGA treatment were screened, and necessary data were extracted. The Kaplan-Meier method and Cox proportional hazards model were used to estimate the DGA survival rate and explore the potential factors affecting the success rate of DGA treatment. Results: Medical records of 852 children were included; 509 (59.7%) children with 1,212 (10.7%) teeth underwent unplanned retreatment. Restoration failure (30.12%) and new caries (29.46%) accounted for the most significant proportion of all failures. The median survival times were 510 and 1,911 days at the child and tooth levels, respectively. Unplanned retreatment risk was associated with the age of S-ECC children, frequency of follow-up, and fluoride application (hazard ratio = 0.97, 0.78, 0.69, P < 0.001). Conclusion: The treatment outcome of DGA administered to children with S-ECC was satisfactory at the tooth level from the perspective of the incidence of unplanned retreatment. Restoration failure was the main reason for the high unplanned retreatment rate. Strategies for a better outcome of DGA include improving the professional knowledge and skills of pediatric dentists and enhancing compliance of parents/patients. Health education and regular topical fluoride application may improve the success rate of DGA treatment.

12.
J Mater Chem B ; 9(11): 2594-2612, 2021 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-33666632

RESUMEN

Bone infection is a devastating disease characterized by recurrence, drug-resistance, and high morbidity, that has prompted clinicians and scientists to develop novel approaches to combat it. Currently, although numerous biomaterials that possess excellent biocompatibility, biodegradability, porosity, and mechanical strength have been developed, their lack of effective antibacterial ability substantially limits bone-defect treatment efficacy. There is, accordingly, a pressing need to design antibacterial biomaterials for effective bone-infection prevention and treatment. This review focuses on antibacterial biomaterials and strategies; it presents recently reported biomaterials, including antibacterial implants, antibacterial scaffolds, antibacterial hydrogels, and antibacterial bone cement types, and aims to provide an overview of these antibacterial materials for application in biomedicine. The antibacterial mechanisms of these materials are discussed as well.


Asunto(s)
Antibacterianos/farmacología , Materiales Biocompatibles/farmacología , Enfermedades Óseas/tratamiento farmacológico , Huesos/efectos de los fármacos , Ingeniería de Tejidos , Antibacterianos/química , Materiales Biocompatibles/química , Enfermedades Óseas/patología , Huesos/patología , Humanos
13.
Environ Technol ; 41(4): 521-528, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30063876

RESUMEN

A typical long process in an iron and steel plant has been investigated with four main manufacturing processes, and nine sample sites were selected, in order to provide a comprehensive understanding of the PM2.5 profile changes caused by the pollutants' control facilities. The result shows pollutants' control facilities have not only affected PM2.5 concentrations, but also the PM2.5 profiles. PM2.5 concentration was increased 1.89 times after Flue gas desulfurization (FGD) in the sintering process, the Ca content in PM2.5 increased to 21.1% caused by the desulfurizing agent; compared with electrostatic precipitator (ESP), bag filter (BF) is more effective for removal of fine particles, especially the condensable particles. The chemical compositions of Cl, K, Pb and Sb decreased after ESP in the sintering process, Fe decreased to 38.0% after ESP in the pelletizing process, and [Formula: see text] and Organic carbon (OC) increased in both processes. Different from ESP, Fe content increased obviously after BF in both blast furnace and converter processes, while S, K, [Formula: see text], and OC are all decreased after BF. The coefficient of divergence (CD) values has been calculated at 0.42∼0.60, showing giant influences of pollutants' control facilities on PM2.5 chemical profiles. Sixteen Polycyclic aromatic hydrocarbons (PAHs) in PM2.5 have been analysed, the result shows that de-dusting facilities (ESP and BF) are quite effective for PAHs removal, and the PAHs' concentration significantly increased after FGD. More efforts are still needed to complete the accurate profile data with the rapid development of pollutants' control technologies.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Ambientales , Hidrocarburos Policíclicos Aromáticos , Monitoreo del Ambiente , Hierro , Material Particulado , Acero
14.
Pest Manag Sci ; 75(7): 1993-1999, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30610748

RESUMEN

BACKGROUND: It is difficult to efficiently silence gene expression in some insects, probably because of the degradation of dsRNA by enzymes present in the gut and hemolymph post-oral feeding or body injecting of dsRNA. We previously developed a nanocarrier delivery system that can systemically deliver dsRNA into chewing mouthpart insects by oral feeding and efficiently silence gene expression. For the purpose of pest control in the field, there is a great demand to develop a spray method to apply dsRNA formulation. RESULTS: A formulation of the nanocarrier/dsRNA/detergent was developed and could be easily applied just by dropping it on the notum of the aphid. The formulation penetrated the body wall into the hemocoel and then spread into various tissues within 1 h. The delivered dsRNA efficiently silenced the target gene expression at a high knockdown effect (95.4%) and the aphid population was largely suppressed (80.5%). CONCLUSION: A novel dsRNA formulation was developed with the help of a nanocarrier and detergent that can quickly penetrate the insect body wall and efficiently silence gene expression. The formulation may provide a fast and easy tool for gene silence in some tough insects and for pest control in the field. © 2019 Society of Chemical Industry.


Asunto(s)
Áfidos/genética , Áfidos/metabolismo , Control de Insectos/métodos , Interferencia de ARN , ARN Bicatenario/administración & dosificación , Administración Cutánea , Animales , Detergentes/química , Expresión Génica , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Nanoestructuras , Polímeros , ARN Bicatenario/genética , ARN Bicatenario/metabolismo
15.
J Mater Chem B ; 7(11): 1875-1881, 2019 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-32255050

RESUMEN

A fluorescent amino poly(glycidyl methacrylate) (PGOHMA) was synthesized by atom transfer radical polymerization (ATRP) and post-polymerization. The obtained star polymer PGOHMA has eight polymer arms enriched with amine groups for gene delivery. PGOHMA showed much lower cytotoxicity and higher delivery efficiency, compared with the widely used commercial and previously reported gene carriers. Therefore, a new star-shaped fluorescent polymer was successfully synthesized and explored as an efficient gene carrier.


Asunto(s)
Técnicas de Transferencia de Gen , Ácidos Polimetacrílicos , Fluorescencia , Terapia Genética/métodos , Células HeLa , Humanos , Imagen Óptica/métodos , Ácidos Polimetacrílicos/síntesis química , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacología
16.
Sci Total Environ ; 693: 133579, 2019 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-31376757

RESUMEN

Biofouling of reverse osmosis (RO) membranes is an inevitable issue in wastewater reclamation and limits the application of RO systems. Chlorine disinfection is widely used as a pretreatment to control biofouling. However, the extracellular polymeric substances (EPS) and cellular inclusions released during chlorine disinfection might also cause membrane fouling. Furthermore, little is known regarding the chlorine resistance of bacterial strains found on fouled RO membranes. In this study, four bacterial strains isolated from fouled RO membranes were used as testing subjects to investigate the bacterial inactivation performance of chlorine disinfection. The effects of chlorine disinfection on the RO membrane fouling potential of these strains were also revealed. The chlorine resistance ability of Sphingopyxis sp. BM1-1 was strongest among the four strains as it secretes the highest amount of EPS per cell. The log inactivation efficiency of this strain was 1-log by 0.2 mg-Cl2/L in 30 min, which was one to three orders of magnitude lower than that of the other strains. Although chlorine disinfection inactivated most bacterial cells (>90%), the reaction with chlorine significantly increased the RO membrane fouling potential of all bacterial solutions. To elucidate the main mechanism behind the increase in the fouling potential, we further investigated the changes in the properties of EPS, and the release of EPS and cellular inclusions during chlorine disinfection. Chlorine disinfection did not significantly affect the RO membrane fouling potential of the EPS secreted by these bacterial strains. However, dissolved organic carbon (DOC), protein, polysaccharide, and DNA concentration of all bacterial solutions increased by one to nine times after chlorine disinfection. These results indicate that large amounts of EPS and cellular inclusions were released into the solutions after the reaction with chlorine, which was the main cause of the increase in RO membrane fouling potential of the bacterial solution after chlorine disinfection.


Asunto(s)
Desinfección/métodos , Eliminación de Residuos Líquidos/métodos , Incrustaciones Biológicas , Cloro , Filtración , Membranas Artificiales , Ósmosis , Aguas Residuales/microbiología
17.
Water Res ; 154: 246-257, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30798179

RESUMEN

In reverse osmosis (RO) system for wastewater reclamation, biofouling is an inevitable issue. Chlorine disinfection is commonly used in pretreatment to control biofouling. Some chlorine-resistant bacteria could survive after chlorine disinfection and the microbial community structure in feed water changes significantly, thus leading to the change of biofouling potential. In this study, the effect of chlorine disinfection on the biofouling of RO membrane was investigated using a laboratory cross-flow RO system. Chlorine disinfection inactivated most bacteria in feed water. However, during the operation of RO system, with the increase of chlorine dosage the flux decline became more severe after a period of operation. The final normalized flux after 21 days was 0.27, 0.26, 0.20, and 0.21 with 0, 1, 5, and 15 mg-Cl2/L chlorine as pretreatment, respectively. After the operation, the numbers of active bacteria in the foulants on the fouled membrane were on the same level regardless of the chlorine dosage, whereas the thickness of the foulants increased with the chlorine dosage significantly. Additionally, the higher total organic carbon concentration indicated more extracellular polymeric substances (EPS) in foulants. Microbial community structure analysis showed that the abundance and the species number of chlorine-resistant bacteria increased significantly with the chlorine dosage. Typical chlorine-resistant bacteria, including Methylobacterium, Pseudomonas, Sphingomonas, and Acinetobacter, were identified as significantly distinctive genera in the foulants after the pretreatment by 15 mg-Cl2/L chlorine. Compared with the bacteria without chlorine disinfection, these remaining bacteria produced more EPS with higher molecular weight, which could be the major contribution to more severe RO membrane fouling after chlorine disinfection.


Asunto(s)
Incrustaciones Biológicas , Purificación del Agua , Cloro , Desinfección , Membranas Artificiales , Ósmosis , Aguas Residuales
18.
JACC Cardiovasc Interv ; 11(23): 2368-2377, 2018 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-30522665

RESUMEN

OBJECTIVES: The aim of the present study was to evaluate the angiographic efficacy, clinical safety, and effectiveness of the Restore paclitaxel-coated balloon in a randomized trial designed to enable the approval of the new device in China. BACKGROUND: Drug-coated balloon (DCB) angioplasty offers an effective treatment for in-stent restenosis. Restore is a new DCB with a SAFEPAX shellac-ammonium salt excipient that can avoid drug washing off during catheter delivery to the target lesion site. METHODS: In the noninferiority RESTORE ISR China (Compare the Efficacy and Safety of RESTORE DEB and SeQuent Please in Chinese Patient With Coronary In-stent Restenosis) trial, eligible patients with first occurrence of drug-eluting stent ISR were randomized to the Restore DCB or SeQuent Please DCB in a 1:1 ratio stratified by diabetes. Angiographic and clinical follow-up was planned at 9 months and 1 year, respectively, in all patients. The study was powered for the primary endpoint of 9-month in-segment late loss. RESULTS: Between May 2016 and July 2017, a total of 240 subjects at 12 sites were randomized to either the Restore group (n = 120) or the SeQuent Please group (n = 120). Nine-month in-segment late loss was 0.38 ± 0.50 mm with Restore versus 0.35 ± 0.47 mm with SeQuent Please; the 1-sided 97.5% upper confidence limit of the difference was 0.17 mm, achieving noninferiority of Restore compared with SeQuent Please (p for noninferiority = 0.02). Both DCBs had similar 1-year rates of target lesion failure (13.3% vs. 12.6%; p = 0.87). CONCLUSIONS: In this head-to-head randomized trial, the Restore DCB was noninferior to the SeQuent Please DCB for the primary endpoint of 9-month in-segment late loss. (Compare the Efficacy and Safety of RESTORE DEB and SeQuent Please in Chinese Patient With Coronary In-stent Restenosis; NCT02944890).


Asunto(s)
Angioplastia Coronaria con Balón/instrumentación , Catéteres Cardíacos , Fármacos Cardiovasculares/administración & dosificación , Materiales Biocompatibles Revestidos , Enfermedad de la Arteria Coronaria/terapia , Reestenosis Coronaria/terapia , Stents Liberadores de Fármacos , Paclitaxel/administración & dosificación , Intervención Coronaria Percutánea/instrumentación , Anciano , Angioplastia Coronaria con Balón/efectos adversos , Fármacos Cardiovasculares/efectos adversos , China , Constricción Patológica , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Reestenosis Coronaria/diagnóstico por imagen , Reestenosis Coronaria/etiología , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Paclitaxel/efectos adversos , Intervención Coronaria Percutánea/efectos adversos , Estudios Prospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
19.
Sci Total Environ ; 644: 486-493, 2018 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-29990899

RESUMEN

Biofouling represents the "Achilles' heel" for reverse osmosis (RO) processes due to the growth of bacteria and their production of extracellular polymeric substances (EPSs). Although the microbial community structure on the RO membrane has been analysed previously, the bacterial species with a high potential of causing RO membrane fouling have not yet been identified clearly. The key components in EPSs causing RO membrane fouling have not been revealed either. In this study, seven different bacterial species were isolated from fouled RO membranes, and their EPSs were analysed in terms of the content of polysaccharides and proteins, fluorescence characteristics and molecular weight (MW) distributions. The membrane fouling potentials of these bacterial species and EPSs were evaluated based on normalized flux decline. Generally, under the same growth conditions, bacterial species with higher EPS concentrations, rather than higher cell numbers, resulted in more severe flux decline. The flux decline showed an apparent positive correlation with the EPS concentration, indicating that the concentration of EPS rather than the bacterial number mainly contributed to biofouling. Furthermore, it was found that the MW distribution was the key factor affecting the RO membrane fouling potential of EPSs from different bacterial species. With the increase in the percentage of the high-MW fraction (>10 kDa) in the EPSs from 12.6% to 74.4%, the normalized flux decline increased from 0.4 to 0.59. The components in EPSs with a MW over 10 kDa were also separated by the ultrafiltration membrane and were proven to have a higher membrane fouling potential.


Asunto(s)
Incrustaciones Biológicas , Membranas Artificiales , Polisacáridos Bacterianos/análisis , Aguas Residuales/microbiología , Purificación del Agua/métodos , Filtración , Ósmosis
20.
Mater Sci Eng C Mater Biol Appl ; 71: 60-66, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-27987750

RESUMEN

The in vitro biodegradable properties and cytocompatibility of Fe-Ga alloys including Fe81Ga19, (Fe81Ga19)98B2 and (Fe81Ga19)99.5(TaC)0.5, and pure Fe were investigated for biomedical applications. The microstructure of the alloys was characterized using X-ray diffraction spectroscopy and optical microscopy. The results showed that A2 and D03 phases were detected for the three types of Fe-Ga alloys, and additional Fe2B and TaC phases were found in the (Fe81Ga19)98B2 and (Fe81Ga19)99.5(TaC)0.5 alloys, respectively. The corrosion rates of the Fe-Ga alloys were higher than that of pure Fe, as demonstrated by both potentiodynamic polarization measurements and immersion tests in simulated body fluid. The alloying element Ga lowered the corrosion potential of the Fe matrix and made it more susceptible to corrosion. Severe pitting corrosion developed on the surface of the Fe81Ga19 alloy after the addition of ternary B or TaC due to the multi-phase microstructures. The MC3T3-E1 cells exhibited good adhesion and proliferation behavior on the surfaces of the Fe-Ga alloys after culture for 4h and 24h.


Asunto(s)
Implantes Absorbibles , Aleaciones , Galio , Hierro , Ensayo de Materiales , Aleaciones/química , Aleaciones/farmacología , Animales , Línea Celular , Corrosión , Galio/química , Galio/farmacología , Hierro/química , Hierro/farmacología , Ratones
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