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1.
Chin J Traumatol ; 25(6): 325-330, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35717367

RESUMEN

PURPOSE: Antibiotic-loaded bone cement (ALBC) was usually used to prevent periprosthetic joint infection (PJI) in primary total knee arthroplasty (PTKA), but whether to use ALBC or plain bone cement in PTKA remains unclear. We aimed to compare the occurrence rate of PJI using two different cements, and to investigate the efficacy of different antibiotic types and doses administered in preventing surgical site infection (SSI) with ALBC. METHODS: The availability of ALBC for preventing PJI was evaluated by using a systematic review and meta-analysis referring to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Existing articles until December 2021 involving PTKA patients with both ALBC and plain bone cement cohorts were scanned by searching "total knee arthroplasty", "antibiotic-loaded cement", "antibiotic prophylaxis", "antibiotic-impregnated cement" and "antibiotic-laden cement" in the database of PubMed/MEDLINE, Embase, Web of Science and the Cochrane Library. Subgroup analysis included the effectiveness of different antibiotic types and doses in preventing SSI with ALBC. The modified Jadad scale was employed to score the qualities of included articles. RESULTS: Eleven quantitative studies were enrolled, including 34,159 knees undergoing PTKA. The meta-analysis results demonstrated that the use of prophylactic ALBC could significantly reduce the prevalence of deep incisional SSI after PTKA, whereas there was no significant reduction in the rate of superficial incisional SSI. Moreover, gentamicin-loaded cement was effective in preventing deep incisional SSI, and the use of high-dose ALBC significantly reduced the rate of deep incisional SSI after PTKA. Besides, no significant adverse reactions and complications were stated during the use of ALBC in PTKA. CONCLUSION: The preventive application of ALBC during PTKA could reduce the rates of deep PJI. Furthermore, bone cement containing gentamicin and high-dose ALBC could even better prevent deep infection after PTKA. However, the existing related articles are mostly single-center and retrospective studies, and further high-quality ones are needed for confirmation.


Asunto(s)
Artritis Infecciosa , Artroplastia de Reemplazo de Rodilla , Infecciones Relacionadas con Prótesis , Humanos , Cementos para Huesos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Rodilla/métodos , Antibacterianos/uso terapéutico , Infecciones Relacionadas con Prótesis/prevención & control , Infecciones Relacionadas con Prótesis/etiología , Estudios Retrospectivos , Artritis Infecciosa/etiología , Gentamicinas , Infección de la Herida Quirúrgica/prevención & control , Infección de la Herida Quirúrgica/tratamiento farmacológico
2.
J Arthroplasty ; 31(5): 1027-34, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26712347

RESUMEN

BACKGROUND: Acetabular reconstruction in adults with Hartofilakidis type B developmental dysplasia of the hip is a major technical challenge. The purpose of this retrospective study was to evaluate hip function and radiographic outcomes regarding high hip center at midterm follow-up. METHODS: From January 1, 2007 to December 31, 2009, 37 patients who had Hartofilakidis type B developmental dysplasia of the hip underwent a primary total hip arthroplasty using a high hip center technique. Functional, radiographic, and survivorship outcomes were evaluated. RESULTS: Of the 37 patients, 31 patients (83.8%) were available for the mean follow-up of 6.1 years (range, 1.5-7.6 years). Thirty-one cementless cups were located at an average vertical distance of 38.1 ± 3.3 mm and at a mean horizontal distance of 35.5 ± 3.4 mm. The mean ratio of the height of the hip center was 2.4% (range, 2.0%-2.9%). The Harris Hip Scores were improved from 50.3 points (range, 38-63 points) preoperatively to 92.3 points (range, 85-100 points) at the final follow-up (P < .001). Four patients continued to present with Trendelenburg gait pattern at the last follow-up. With use of revision for any reason and aseptic loosening as the end point, the 5-year survival rates were 90.3% (95% CI, 79.9%-100%) and 93.3% (95% CI, 84.3%-100%), respectively. CONCLUSIONS: The high hip center technique in conjunction with a cementless acetabular component seems to be a valuable alternative to achieve satisfactory midterm outcomes for Hartofilakidis type B developmental dysplasia of the hip.


Asunto(s)
Artroplastia de Reemplazo de Cadera/métodos , Luxación Congénita de la Cadera/cirugía , Articulación de la Cadera/cirugía , Acetábulo/diagnóstico por imagen , Acetábulo/cirugía , Adulto , Anciano , Cementos para Huesos , Femenino , Estudios de Seguimiento , Luxación Congénita de la Cadera/diagnóstico por imagen , Luxación Congénita de la Cadera/fisiopatología , Articulación de la Cadera/diagnóstico por imagen , Prótesis de Cadera , Humanos , Masculino , Persona de Mediana Edad , Falla de Prótesis , Recuperación de la Función , Estudios Retrospectivos , Resultado del Tratamiento
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 46(1): 87-9, 98, 2015 Jan.
Artículo en Zh | MEDLINE | ID: mdl-25807802

RESUMEN

OBJECTIVE: To determine adhesion of Streptococcus mutans (S. mutans) to different kinds of removable denture crowns for the purpose of minimizing influence of removable denture on oral environment. METHODS: Three kinds of removable denture crowns (single color synthetic resin teeth, alloy pin porcelain tooth and minute color synthetic resin teeth) were adsorbed S. mutans for 24 h in sterile saliva, The adhered bacteria were counted by means of sonic oscillation and bacteria coating. RESULTS: Highest level of adhesion was found on ,the single color synthetic resin teeth was adsorbed mostly, followed by alloy pin porcelain teeth. Minute color synthetic resin teeth had far less adhesion than the others (P<0.01). CONCLUSION: Minute color synthetic resin teeth have less adhesion of S. mutans, which may be associated with their lower level of surface free energy.


Asunto(s)
Adhesión Bacteriana , Coronas/microbiología , Streptococcus mutans , Porcelana Dental , Dentadura Parcial/microbiología , Propiedades de Superficie , Diente Artificial/microbiología
5.
Int J Biol Macromol ; 257(Pt 1): 128582, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38056751

RESUMEN

Lignin-based slow-release fertilizers (SRFs) have attracted widespread attention due to their ability to enhance nutrient utilization efficiency and reduce environmental pollution in agricultural production. However, the extraction and separation processes of lignin from biomass sources are intricate, involving substantial quantities of non-reusable toxic reagents. Here, a sustainable and eco-friendly approach using deep eutectic solvents (DES) was employed to treat rice straw, effectively dissolving the lignin present. Subsequently, the in-situ lignin regeneration was facilitated through the addition of a zinc chloride solution. The regenerated lignin was tightly wrapped around and connected to cellulose micro/nanofibers, forming a homogeneous slurry. A simple coating technique was employed to uniformly coat urea particles with the lignocellulosic slurry, yielding lignocellulose-based SRFs. Results revealed that the nutrient release of the lignocellulose-based coated fertilizers in water exceeded 56 days. A pot trial demonstrated that the application of lignocellulose-based SRFs significantly promoted the growth of rice and improved grain yield (by 10.7 %) and nitrogen use efficiency (by 34.4 %) compared to the urea treatment in rice production. Furthermore, the DES demonstrated consistently high efficiency in biomass processing even after four cycles of reuse. This green strategy offers a novel approach for the preparation of SRFs coating materials, promoting agricultural sustainability.


Asunto(s)
Lignina , Oryza , Disolventes Eutécticos Profundos , Fertilizantes , Solventes , Biomasa , Urea , Hidrólisis
6.
Curr Med Imaging ; 19(4): 382-388, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36125820

RESUMEN

OBJECTIVE: The study aims to conduct lung cancer screening by low-dose CT to identify the nature of the pulmonary nodule. The purpose of this study was to evaluate the role of preoperative medical EC glue localization of pulmonary nodules of uncertain nature by minimally invasive surgical resection. METHODS: From December 2017 to December 2019, 18 patients (12 women, 6 men; median age: 54 years)with pulmonary nodules were located using medical EC glue under the guidance of preoperative CT and then resected under video thoracoscopy at Air Force Medical Center of PLA. The clinical characteristics were retrospectively collected to evaluate the effectiveness, safety and feasibility of the operation. RESULTS: The mean value of the maximum diameter of pulmonary nodules on CT images before the operation was 10.8 mm. The average depth was 10.3 mm (1.0-39.5 mm). Among 18 nodules, 8 were pure ground glass nodules, 3 were solid nodules, and 7 were partial solid nodules. The diagnosis rate of medical glue localization under the guidance of CT after the operation was 100%. Postoperative pathological diagnosis showed that there were 10 cases of primary lung adenocarcinoma, 1 case of invasive lung adenocarcinoma, 3 cases of adenocarcinoma in situ, 1 case of metastatic adenocarcinoma, and 3 cases of benign nodules. No obvious serious complications were found after localization. CONCLUSION: This study suggests that CT-guided percutaneous medical EC glue localization is a reliable, safe, feasible and practical method for undiagnosed pulmonary nodules and can significantly improve the rate of resection of small pulmonary nodules. Furthermore, it was considered to be more reasonable to remove pulmonary nodules and maximize the preservation of lung function.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Nódulos Pulmonares Múltiples , Masculino , Humanos , Femenino , Persona de Mediana Edad , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Neoplasias Pulmonares/patología , Cianoacrilatos/uso terapéutico , Adhesivos , Estudios Retrospectivos , Detección Precoz del Cáncer , Cirugía Torácica Asistida por Video/métodos , Nódulos Pulmonares Múltiples/diagnóstico por imagen , Nódulos Pulmonares Múltiples/cirugía , Nódulos Pulmonares Múltiples/patología , Tomografía Computarizada por Rayos X/métodos
7.
Chin J Dent Res ; 25(2): 125-130, 2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35686592

RESUMEN

OBJECTIVE: To evaluate the change in demineralisation depth (DD)and mineral density (MD) over time in primary teeth exposed to a demineralisation protocol with microcomputed tomography (microCT). METHODS: Caries lesions were artificially induced on the labial surfaces of 9 primary incisors by way of a demineralisation protocol using 0.1 M lactic acid with 10% methylcellulose gel for 7 and 14 days. The specimens were scanned with microCT and CTAn software (Bruker, Billerica, MA, USA) was used to analyse the changes in DD and MD. Statistical analyses were performed using SPSS software (IBM, Armonk, NY, USA). Repeated analysis of variance (ANOVA) test and Pearson bivariate correlation were used and the level of significance was set at P < 0.05. RESULTS: The DD ranged from 0.00 to 0.99 µm (mean ± standard deviation [SD] 0.70 ± 0.43 µm) at baseline, 11.18 to 29.5 µm (18.15 ± 5.23 µm) at 7 days and 18.00 to 55.30 µm (34.20 ± 8.70 µm) at 14 days. The MD for all specimens (n = 9) ranged from 1.48 to 1.76 g/cm3 (1.65 ± 0.08 g/cm3) at baseline, from 1.47 to 1.74 g/cm3 (1.62 ± 0.08 g/cm3) at 7 days demineralisation and 1.33 to 1.72 g/cm3 (1.54 ± 0.13 g/cm3) at 14 days. There were statistically significant differences in DD (P < 0.001) and MD (P = 0.016) between different durations of demineralisation. CONCLUSION: DD and MD change with time after being exposed to demineralising solution. MicroCT is a nondestructive method that allows repeated MD evaluations of the same sample.


Asunto(s)
Caries Dental , Caries Dental/diagnóstico por imagen , Humanos , Minerales/análisis , Diente Primario , Microtomografía por Rayos X/métodos
8.
Heliyon ; 8(8): e10379, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36061014

RESUMEN

Background: Orthodontic tooth movement mainly depends on biological and mechanical reactions in the periodontium, such as the indispensable reconstruction process of the periodontal ligament and alveolar bone. To explore whether orthodontic compressive force can induce bone resorption during orthodontic tooth movement by regulating the GSK-3ß/ß-catenin pathway. Methods: We established orthodontic tooth movement models in Sprague-Dawley rats. In addition, compressive force-induced bone resorption that occurred during orthodontic tooth movement was analyzed by HE staining and micro-CT. The number and distribution of osteoclasts were observed by TRAP staining. Furthermore, pressure-induced bone resorption mediated by the GSK-3ß/ß-catenin signaling pathway was analyzed by immunohistochemistry. Results: As shown by the micro-CT results, bone parameters, such as bone mineral density (BMD), the bone volume fraction (BV/TV), and trabecular thickness (Tb. Th), were significantly decreased under orthodontic compressive force stimulation, in contrast with the dramatically increased trabecular spacing (Tb. Sp). During the process of tooth movement, the compressive force can induce bone resorption on the side with the force, which increases the expression of phosphorylated Ser-GSK-3ß and activation of the ß-catenin signaling pathway. Additionally, downregulation of the GSK-3ß activity further caused the downregulation of bone parameters, leading to bone loss. The TRAP staining and immunohistochemistry staining results indicated that orthodontic compressive force influenced osteoclast formation and the secretion of osteoclast-related cytokines, matrix metallopeptidase 9 (MMP-9) and receptor activator of nuclear factor-κB ligands (RANKLs), which is also related to the duration of orthodontic force. Conclusions: These results indicated that the GSK-3ß inhibitor can promote osteoclast formation on the side with orthodontic compressive force. In addition, the activation of the GSK-3ß/ß-catenin signaling pathway contributes to bone reconstruction caused by orthodontic compressive force. Therefore, the GSK-3ß/ß-catenin signaling pathway can be a potential target for further clinical applications.

9.
Front Pediatr ; 10: 1008251, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36340727

RESUMEN

Background: Pathogenic variants in the FIG4 gene have been described to be associated with a diverse spectrum of syndromes, such as autosomal recessive bilateral temporooccipital polymicrogyria (OMIM 612691), autosomal dominant amyotrophic lateral sclerosis-11 (ALS11; OMIM 612577), autosomal recessive Charcot-Marie-Tooth disease, type 4J (CMT4J; OMIM 611228), and autosomal recessive Yunis-Varon syndrome (YVS; OMIM 216340). Heterozygous FIG4 variants are responsible for ALS11 characterized by progressive muscular weakness, atrophy, and bulbar palsy. CMT4J is a disorder of peripheral nervous system defects mainly presenting with a highly variable onset of proximal and/or distal muscle weakness. YVS is a disorder of severe neurological involvement with central nervous system (CNS) dysfunction and extensive skeletal anomalies. Case Presentation: We reported two Chinese siblings born with a weakness in all limbs. They experienced rapidly progressive weakness in distal limbs. At the age of 6 years, the elder brother presented with severe scoliosis and cervical kyphosis. They both had global developmental delay and a CNS involvement with cognitive deficits and swallowing problems. Genetic screening in the patients' family for inherited diseases was recommended. Novel compound heterozygous variants in the FIG4 gene (c.2148delTinsAA and c.317A > G) were found by whole-exome sequencing in the patients. These variants were confirmed by Sanger sequencing in family members. Conclusions: Herein, we reported two Chinese male patients with CMT4J who presented with abnormal CNS features. CMT4J with CNS involvement has been very rarely reported. We hoped this study could expand the phenotypic and genetic spectrum of FIG4-related diseases. And we helped physicians to understand the genotype-phenotype correlation.

10.
Appl Radiat Isot ; 178: 109958, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34598040

RESUMEN

The TE101 mode rectangle EPR cavity was newly developed to achieve X-band in vivo EPR tooth dosimetry for the rescue of nuclear emergency. An aperture for sample detection was opened on the cavity's surface. Its characteristics were evaluated by measuring DPPH and intact human incisor samples. Remarkable radiation induced signal from EPR spectrum of 1Gy-8Gy irradiated teeth was observed. In vivo measurements of rat was performed to verify its application for in vivo tooth dosimetry.


Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón/métodos , Radiometría/métodos , Diente/diagnóstico por imagen , Animales , Espectroscopía de Resonancia por Spin del Electrón/instrumentación , Diseño de Equipo , Femenino , Humanos , Radiometría/instrumentación , Ratas , Ratas Sprague-Dawley
11.
Plant Physiol Biochem ; 167: 49-67, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34332254

RESUMEN

In plants, NO has been proved the function of improving abiotic stress resistance. However, the role of NO in the lignin metabolism of okra under cold stress has not been clarified. Here, histochemical staining and lignin content analysis showed that cold stress promoted the lignin accumulation of cold stored okra pods, and NO inhibited the lignin accumulation and delayed lignification process. To better understand the roles of NO in okra cold stress resistance mechanism, the full-length transcriptome data of 'Hokkaido' was analyzed. The SNP-treated okra transcriptome and cPTIO-treated okra transcriptome were obtained. A total of 41957 unigenes were screened out from three groups at 10 d, among which, 33, 78 and 18 DEGs were found in ddH2O-treat, SNP-treat and cPTIO-treat group, respectively. Transcriptomic data suggested that the genes involved in lignin biosynthesis showed downregulation under SNP treatment. Transcriptomic data and enzyme activity showed that exogenous NO significantly promoted the biosynthesis of endogenous NO by enhancing NOS activity. Transcriptomic data and plant hormone data showed that NO played an important role in the process of inhibiting the ethylene and ABA synthesis mechanism of okra and thereby reducing the endogenous ethylene and ABA content under chilling stress. Relevant physiological data showed that NO helped to the protection of ROS scavenging system and removed the MDA and H2O2 induced by cold stress. These results provided a reference for studying the molecular mechanism of nitric oxide delaying the lignification of okra, and also provided a theoretical basis for postharvest storage of vegetables.


Asunto(s)
Abelmoschus , Perfilación de la Expresión Génica , Peróxido de Hidrógeno , Lignina , Óxido Nítrico , Transcriptoma
12.
Curr Med Sci ; 40(4): 753-760, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32862387

RESUMEN

Studies have shown that periodontal pathogens can enter the bloodstream, causing a series of reactions that can lead to a variety of systemic diseases. Epidemiological investigations also found a tight correlation between periodontitis (PD) and osteoporosis. This study aimed to further explore the effect of periodontal pathogens on bone volume fraction like bone tissue and mass, and explain the relationship between PD and osteoporosis. Sprague Dawley rats (female, 16 weeks old) were divided into the wild-type (WT) control group (n=9) and PD group (n=9). After eight weeks, periodontal tissues and ligatures, the fourth lumbar vertebra, the femur, the tibia, and blood were extracted and analyzed by micro-computed tomography (micro-CT), hematoxylin and eosin (H&E) staining, tartrate-resistant acid phosphatase (TRAP) staining, polymerase chain reaction (PCR), and enzyme-linked immunoassay (ELISA), respectively. We found that the bone mass of the lumbar vertebra, femur, and tibia was decreased in the PD group. The number of osteoclasts was higher in bone tissue in the PD group than in the WT group (P<0.05). The levels of inflammatory mediators and type I collagen C-terminal peptide (CTX-1) were higher in the PD group than in the WT group (P<0.05), although no significant difference in bone glutamic acid protein (BGP) levels was observed (P>0.05). In addition, we detected several periodontal pathogens, such as Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, and Fusobacterium nucleatum, in blood samples from rats in the PD group. These findings suggest that periodontal pathogens can enter the blood circulation from periodontal tissue, promote a systemic inflammation response, and subsequently reduce systemic bone density.


Asunto(s)
Sangre/microbiología , Osteoclastos/metabolismo , Osteoporosis/diagnóstico por imagen , Periodontitis/sangre , Aggregatibacter actinomycetemcomitans/aislamiento & purificación , Animales , Densidad Ósea , Modelos Animales de Enfermedad , Femenino , Fémur/diagnóstico por imagen , Fémur/patología , Fusobacterium nucleatum/aislamiento & purificación , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/patología , Osteoporosis/microbiología , Periodontitis/microbiología , Porphyromonas gingivalis/aislamiento & purificación , Ratas , Ratas Sprague-Dawley , Tibia/diagnóstico por imagen , Tibia/patología , Microtomografía por Rayos X
13.
Biosens Bioelectron ; 153: 112019, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31989935

RESUMEN

Adenosine triphosphate (ATP) plays a crucial role in energy metabolism and extracellular purinergic signaling. A 3D bimetallic Au/Pt nanoflowers decorated ATP microelectrode biosensor prepared by facile and effective template-free electrodeposition was firstly reported, realizing local detection of cellular ATP secretion. The ATP biosensor was developed by co-immobilization of glucose oxidase and hexokinase, exhibiting long-term stability (79.39 ± 9.15% of its initial value remained after 14 days at 4 °C) and high selectivity with a limit of detection down to 2.5 µM (S/N = 3). The resulting ATP biosensor was then used for direct in situ monitoring of ATP secreted from living cells (PC12) with the stimulation of high K+ solutions. The obtained current was about 21.6 ± 3.4 nA (N = 6), corresponding to 12.2 ± 2.8 µM ATP released from cells, right in the micromolar range and consistent with the suggested levels. The 3D bimetallic Au/Pt nanoflowers possess excellent catalytic activity and large electroactive surface area, contributing to enzymatic activity preservation and long-term stability. This work provides a promising platform for long-time monitoring of other neurotransmitters and secretions in cellular glycolysis and apoptosis processes in the future.


Asunto(s)
Adenosina Trifosfato/análisis , Aleaciones/química , Oro/química , Nanopartículas del Metal/química , Platino (Metal)/química , Animales , Técnicas Biosensibles , Catálisis , Galvanoplastia , Enzimas Inmovilizadas/química , Glucosa Oxidasa/química , Hexoquinasa/química , Peróxido de Hidrógeno/química , Límite de Detección , Microelectrodos , Células PC12 , Ratas , Sensibilidad y Especificidad , Propiedades de Superficie
14.
Appl Radiat Isot ; 149: 123-129, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31054478

RESUMEN

The accuracy of in vivo EPR tooth dosimetry may be influenced by the volume and geometry variations in teeth, especially when there is considerable non-uniform sensitivity distribution in the active detection area of the cavity. To solve this problem, the present research proposed a normalization method specifically for X-band EPR in vivo tooth dosimetry. The volume and geometry of the measured tooth were reconstructed by digital image processing with images of the tooth impression slices, which were obtained by a custom-made impression module. The sensitivity distribution in the active detection area was established based on experiments with a point sample. Consequently, a composite normalization process that could calibrate the evaluated dose effectively was carried out by taking into account the influences not only from tooth volume and geometry but also from the non-uniform distribution of sensitivity. The effect and practicability of the method were evaluated by incisor samples. Results showed that the standard deviation could be reduced a maximum of 54.8% approximately after the composite normalization, an improvement compared to results from solely tooth volume. The correlation coefficient of the dose-response curve could be improved from 0.731 to 0.986. The preliminary method provides an approach potentially useful on site after radiation accidents when dealing with the influence of variations in the tooth volume and geometry for X-band EPR in vivo dose estimations.

15.
J Mater Chem B ; 7(20): 3310-3318, 2019 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-31998923

RESUMEN

We report here for the first time how the combination of a precursor solution and low temperature (170 °C) aerosol assisted chemical vapour deposition were used to bond a copper coating to ultra-high molecular weight polyethylene (UHMWPE) and promote robustness. This metallic thin film remained intact on the UHMWPE substrate after the Scotch tape test and showed notable wear-resistance after 10 cycles of sand paper-abrasion. Antimicrobial assays against both Escherichia coli and Staphylococcus aureus revealed potent dark bactericidal activity with 99.999% reduction in bacterial number within 15 minutes. These results suggest that the modified UHMWPE could be a potential candidate for antimicrobial plastics and in the long term may find application in prosthetic joint applications.


Asunto(s)
Antibacterianos/uso terapéutico , Artroplastia de Reemplazo/instrumentación , Cobre/química , Ensayo de Materiales/métodos , Polietilenos/uso terapéutico , Estudios de Factibilidad , Polietilenos/farmacología
16.
Environ Sci Pollut Res Int ; 25(6): 5491-5500, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29214482

RESUMEN

Ultraviolet-visible (UV-Vis) absorbance spectra were adopted to quantify the binding of metal ions (e.g., Fe(III), Cu(II), Pb(II), and Cd(II)) on three MW fractions (> 100, 10~100, and < 10 k Da) of extracellular polymeric substances (EPS) extracted from mixed cultures dominated by anaerobic ammonium-oxidizing bacteria (AnAOB). The results showed that the AnAOB EPS with different MW size ranges all had strongest binding capability of Fe(III), and the lowest binding capability of Cd(II). The complexation ability of metal ions for the EPS of AnAOB with molecular weight < 10 kDa was stronger than EPS with >100 and 10~100 kDa, very likely because of the contribution of the tyrosine-, tryptophan-, and aromatic protein-like components. It was obvious that the different size fractions of EPS affect the metal binding ability. Essentially, the content of proteins, polysaccharides, TOC, and UVA254 distributed within various MW fractions of EPS from AnAOB were different, as well as the different fluorescent components and total functional groups.


Asunto(s)
Bacterias/metabolismo , Metales/metabolismo , Polímeros/metabolismo , Compuestos de Amonio/metabolismo , Bacterias/química , Iones/metabolismo , Metales/química , Peso Molecular , Polímeros/química , Polisacáridos/química , Proteínas/química
17.
J Mater Chem B ; 6(13): 1862-1886, 2018 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-32254353

RESUMEN

Titanium dioxide nanotubes (TNTs) have drawn wide attention and been extensively applied in the field of biomedicine, due to their large specific surface area, good corrosion resistance, excellent biocompatibility, and enhanced bioactivity. This review describes the preparation of TNTs and the surface modification that entrust the nanotubes with better antibacterial property and enhanced osteoblast adhesion, proliferation, and differentiation. Considering the contact between TNTs' surface and surrounding tissues after implantation, the interactions between TNTs (with properties including their diameter, length, wettability, and crystalline phase) and proteins, platelets, bacteria, and cells are illustrated. The state of the art in the applications of TNTs in dentistry, orthopedic implants, and cardiovascular stents are introduced. In particular, the application of TNTs in biosensing has attracted much attention due to its ability for the rapid diagnosis of diseases. Finally, the difficulties and challenges in the practical application of TNTs are also discussed.

18.
PLoS One ; 13(5): e0197953, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29813104

RESUMEN

The development of new dosimeters with good dosimetric properties is important for quality control in radiation applications. A new practical electron spin resonance (ESR) dosimeter based on carbonated hydroxyapatite that simulated the composition and structure of tooth enamel was specially synthesized. The synthesized material was investigated by transmission electron microscope, X-ray diffraction, fourier transform infrared spectroscopy and X-ray photo electron spectroscopy to confirm to the main composition of carbonated hydroxyapatite with CO32- successfully doped into the crystal lattice through optimizing the synthesis process of C/P molar ratio, pH value dynamical adjustment, annealing temperature and time. The dosimetric properties were systematically investigated by ESR spectroscopy. The results indicated that the radiation induced signal had a good dose response within a relatively wide dose range. The dose response was linear in the dose range of 0-400 Gy with a correlation coefficient of 0.9999 and had dose accumulative effect in the experimental dose range of 0-100 Gy. In a wider dose range up to 30 kGy, the dose response also presented linear feature in double-logarithmic coordinate system with a correlation coefficient of 0.9970. The dose detection limit was about 0.34Gy with a given probability of 95% confidence level depending upon a rigid calculation algorithm. The signal was extremely stable in the observation time of 360 days with a variation coefficient of 3.8%. The radiation sensitivity of the material showed no remarkable variation against photon energy from 662 KeV to 1.25 MeV and dose rate from 0.86 Gy/min to 12.17 Gy/min. The material showed more sensitive in lower photon energy range below 662 keV, which hint additional calibration may need when using in special photon energy condition. The preliminary results suggested that this newly developed dosimeter was potential to become a practical dosimeter that would expand the application fields of ESR dosimetry.


Asunto(s)
Carbonatos/química , Durapatita/química , Espectroscopía de Resonancia por Spin del Electrón , Dosímetros de Radiación , Límite de Detección , Fotones
19.
Appl Radiat Isot ; 139: 86-90, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29729486

RESUMEN

The X-band in vivo EPR tooth dosimetry is promising as a tool for the initial triage after a large-scale radiation accident. The dielectric losses caused by water on the tooth surface (WTS) are one of the major sources of inaccuracies in this method. The effect was studied by theoretical simulation calculations and experiments with water films of various thicknesses on teeth. The results demonstrate the possibility of sufficiently accurate measurements of the radiation-induced signal of the tooth enamel provided that the thickness of the water film on the tooth is below 60 µm. The sensitivity of the cavity decreases with increasing thickness of the water layer. The interference of WTS can be diminished by normalization of the radiation-induced signal to the signal of a reference sample permanently present in the cavity.


Asunto(s)
Esmalte Dental/química , Esmalte Dental/efectos de la radiación , Espectroscopía de Resonancia por Spin del Electrón/métodos , Traumatismos por Radiación/diagnóstico por imagen , Agua/análisis , Calibración , Espectroscopía de Resonancia por Spin del Electrón/normas , Espectroscopía de Resonancia por Spin del Electrón/estadística & datos numéricos , Humanos , Fantasmas de Imagen , Exposición a la Radiación/análisis , Liberación de Radiactividad Peligrosa , Radiometría/métodos , Radiometría/normas , Radiometría/estadística & datos numéricos , Estándares de Referencia
20.
Zhongguo Zhong Yao Za Zhi ; 31(20): 1696-9, 2006 Oct.
Artículo en Zh | MEDLINE | ID: mdl-17225539

RESUMEN

OBJECTIVE: To study the chemical constituents from the roots and rhizomes of Clematis hexapetala. METHOD: The compounds were separated by means of solvent extraction, repeated chromatography with silica gel and HPLC. The structures were determined by spectral analysis. RESULT: Nine compounds were isolated as friedelin (1) , anemonin (2) , beta-sitosterol (3) , palmitic acid (4) , vanillic acid (5) , isolariciresinol (6) , 5-hydroxumethyl-5H-furan-2-one (7) , n-nonane (8) , daucosterol (9). CONCLUSION: All the compounds were isolated from the plant for the first time.


Asunto(s)
Clematis/química , Furanos/aislamiento & purificación , Lignina/aislamiento & purificación , Naftoles/aislamiento & purificación , Plantas Medicinales/química , Triterpenos/aislamiento & purificación , Furanos/química , Lignina/química , Naftoles/química , Ácido Palmítico/química , Ácido Palmítico/aislamiento & purificación , Raíces de Plantas/química , Rizoma/química , Sitoesteroles/química , Sitoesteroles/aislamiento & purificación , Triterpenos/química
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