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Human brain gray matter (GM) has usually been clustered into multiple functional networks. The white matter (WM) fiber bundles are known to interconnect these networks simultaneously, engaging in numerous cognitive functions. However, the exact interconnections between GM and WM are still unclear, whether functional signals in WM rewires GM community organization remains to be explored. In this study, we divided brain functional connections into three types by using edge-centric method, including intra-GM, intra-WM and GM-WM connections, and calculated the edge community evaluation indexes for quantifying GM community engagement. The results showed that the involvement of WM significantly enhanced community entropy in the heteromodal system, while the sensory-attention system remained barely changed. In addition, delta community entropy showed a significant correlation with clinical cognitive scale. Our results suggested that WM rewired GM community organization, enhancing the community engagement of brain regions in the heteromodal system. This involvement was observed to be disrupted in disease groups. Our study revealed that considering the functional signals of GM and WM simultaneously could better understand the brain's functional organization.
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Sustancia Gris , Imagen por Resonancia Magnética , Sustancia Blanca , Humanos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiología , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/anatomía & histología , Sustancia Gris/fisiología , Masculino , Femenino , Adulto , Adulto Joven , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiología , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , AncianoRESUMEN
Economic decision-making is pivotal to both human private interests and the national economy. People pursue fairness in economic decision-making, but a proposer's moral identity can influence fairness processing. Previous ERP studies have revealed that moral identity has an effect on fairness considerations in the Ultimatum Game (UG), but the findings are inconsistent. To address the issue, we revised the moral-related sentences and used the ERP technique to measure the corresponding neural mechanism. We have observed that the fairness effect in UG can be mirrored in both MFN and P300 changes, whereas the moral identity effect on fairness in UG can be reflected by MFN but not P300 changes. These findings indicate that the moral identity of the proposer can modulate fairness processing in UG. The current study opens new avenues for clarifying the temporal course of the relationship between the proposer's moral identity and fairness in economic decision-making, which is beneficial for understanding the influencing mechanism of fairness processing and fair allocations in complex social contexts.
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Toma de Decisiones , Potenciales Evocados , Juegos Experimentales , Principios Morales , Humanos , Masculino , Adulto Joven , Femenino , Toma de Decisiones/fisiología , Adulto , Potenciales Evocados/fisiología , Electroencefalografía , Encéfalo/fisiologíaRESUMEN
Bulbophyllum is one of the largest genera and presents some of the most intricate taxonomic problems in the family Orchidaceae, including species of ornamental and medical importance. The lack of knowledge regarding the characterization of Bulbophyllum chloroplast (cp) genomes has imposed current limitations on our study. Here, we report the complete cp genomes of seven Bulbophyllum species, including B. ambrosia, B. crassipes, B. farreri, B. hamatum, B. shanicum, B. triste, and B. violaceolabellum, and compared with related taxa to provide a better understanding of their genomic information on taxonomy and phylogeny. A total of 28 Bulbophyllum cp genomes exhibit typical quadripartite structures with lengths ranging from 145,092 bp to 165,812 bp and a GC content of 36.60% to 38.04%. Each genome contained 125-132 genes, encompassing 74-86 protein-coding genes, 38 tRNA genes, and eight rRNA genes. The genome arrangements, gene contents, and length were similar, with differences observed in ndh gene composition. It is worth noting that there were exogenous fragment insertions in the IR regions of B. crassipes. A total of 18-49 long repeats and 38-80 simple sequence repeats (SSRs) were detected and the single nucleotide (A/T) was dominant in Bulbophyllum cp genomes, with an obvious A/T preference. An analysis of relative synonymous codon usage (RSCU) revealed that leucine (Leu) was the most frequently used codon, while cysteine (Cys) was the least used. Six highly variable regions (rpl32-trnLUAG > trnTUGU-trnLUAA > trnFGAA-ndhJ > rps15-ycf1 > rbcL-accD > psbI-trnSGCU) and five coding sequences (ycf1 > rps12 > matK > psbK > rps15) were identified as potential DNA markers based on nucleotide diversity. Additionally, 31,641 molecular diagnostic characters (MDCs) were identified in complete cp genomes. A phylogenetic analysis based on the complete cp genome sequences and 68 protein-coding genes strongly supported that 28 Bulbophyllum species can be divided into four branches, sects. Brachyantha, Cirrhopetalum, and Leopardinae, defined by morphology, were non-monophyly. Our results enriched the genetic resources of Bulbophyllum, providing valuable information to illustrate the complicated taxonomy, phylogeny, and evolution process of the genus.
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Genoma del Cloroplasto , Orchidaceae , Filogenia , Orchidaceae/genética , Evolución Molecular , NucleótidosRESUMEN
Extracellular vesicles (EVs) or exosomes are nanosized extracellular particles that contain proteins, DNA, non-coding RNA (ncRNA) and other molecules, which are widely present in biofluids throughout the body. As a key mediator of intercellular communication, EVs transfer their cargoes to target cells and activate signaling transduction. Increasing evidence shows that ncRNA is involved in a variety of pathological and physiological processes through various pathways, particularly the inflammatory response. Macrophage, one of the body's "gatekeepers", plays a crucial role in inflammatory reactions. Generally, macrophages can be classified as pro-inflammatory type (M1) or anti-inflammatory type (M2) upon their phenotypes, a phenomenon termed macrophage polarization. Increasing evidence indicates that the polarization of macrophages plays important roles in the progression of cardiovascular diseases (CVD). However, the role of exosomal ncRNA in regulating macrophage polarization and the role of polarized macrophages as an important source of EV in CVD remains to be elucidated. In this review, we summarize the role and molecular mechanisms of exosomal-ncRNA in regulating macrophage polarization during CVD development, focusing on their cellular origins, functional cargo, and their detailed effects on macrophage polarization. We also discuss the role of polarized macrophages and their derived EV in CVD as well as the therapeutic prospects of exosomal ncRNA in the treatment of CVD.
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Quitinasas , Infarto del Miocardio , Humanos , Infarto del Miocardio/diagnóstico , LectinasRESUMEN
What is already known about this topic?: Typhoid fever remains a major public health problem in developing countries. Waterborne typhoid fever affects an estimated 27 million people worldwide each year. Decades of indiscriminate antibiotic usage has driven the emergence and spread of multidrug-resistant (MDR) and even extensively drug-resistant (XDR) Salmonella Typhi (S. Typhi) strains. What is added by this report?: By combining the epidemiological investigations, bacterial isolation from patients and household water, whole genome sequencing and drug resistance analysis, we identified a waterborne typhoid fever outbreak caused by XDR S. Typhi in Beijing municipality. This was the first report of the XDR S. Typhi triggered outbreak in Beijing, which was also rare in China. What are the implications for public health practice?: This report highlights the importance of ensuring access to affordable and safe drinking water, improved sanitation, and waste management systems for resource-constrained urban populations. Typhoid fever caused by XDR S. Typhi is still a severe public health threat.
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OBJECTIVE: The pharmacokinetics of lamotrigine exhibits age-related characteristics. Nevertheless, current evidence regarding the therapeutic range of lamotrigine has been derived almost exclusively from studies in adult patients, and the applicability of this therapeutic range to the pediatric population remains unclear. The purpose of this study was to establish the appropriate age-specific therapeutic ranges of lamotrigine corresponding to adequate clinical responses for patients with epilepsy. METHODS: This prospective cohort study of therapeutic drug monitoring included 582 Chinese epilepsy patients receiving lamotrigine monotherapy. Patients were divided into three age-related subgroups: (1) toddler and school-age group (2-12 years old, n = 168), (2) adolescent group (12-18 years old, n = 171), and (3) adult group (>18 years old, n = 243). Patients with a reduction in seizure frequency of 50 % or greater than baseline were defined as responders, and the remaining patients were non-responders. The relationship between lamotrigine serum concentrations and clinical response was assessed using multivariate logistic regression analysis. A receiver operating characteristic curve was generated to determine the representative cut-off values of lamotrigine trough levels, to distinguish responders from non-responders. The upper margin of the therapeutic range of lamotrigine was determined by developing concentration-effect curves for the three age-related subgroups. RESULTS: The median trough levels of lamotrigine were significantly higher in responders than in non-responders from all three age-related groups (P < 0.0001). Results of logistic regression analysis revealed that higher serum concentrations of lamotrigine predicted a higher probability that seizure frequency would be reduced by more than 50 % compared to baseline (adjusted odds ratio: 1.228, 95 % CI: 1.137-1.327; P < 0.0001), and younger children were less likely to be responders (adjusted odds ratio: 1.027, 95 % CI: 1.012-1.043; P = 0.001). Based on a trade-off between sensitivity and specificity, the optimal cut-off values for lamotrigine trough concentrations corresponding to clinical response were 3.29 mg/L, 2.06 mg/L, and 1.61 mg/L in the toddler and school-age group, adolescent group, and adult group, respectively. By reducing interpatient variability, the results of the concentration-effect curves suggested no additional clinical benefit from a continued increase of doses for lamotrigine concentrations exceeding 9.08 mg/L, 8.43 mg/L, and 10.38 mg/L in the toddler and school-age group, adolescent group, and adult group, respectively. In conclusion, the therapeutic ranges of lamotrigine trough concentrations corresponding to adequate clinical response were 3.29-9.08 mg/L in the toddler and school-age group, 2.06-8.43 mg/L in the adolescent group, and 1.61-10.38 mg/L in the adult group. CONCLUSIONS: The study determined age-specific therapeutic ranges corresponding to optimal clinical efficacy for lamotrigine. Our findings lay the foundation for catalyzing novel opportunities to optimize treatment and reduce therapeutic costs. Based on the age-specific therapeutic ranges identified in this study, individualized and cost-effective algorithms for lamotrigine treatment of epilepsy patients may be developed and validated in larger cohort studies of therapeutic drug monitoring.
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Epilepsia , Triazinas , Adolescente , Adulto , Factores de Edad , Anticonvulsivantes/efectos adversos , Niño , Preescolar , Análisis Costo-Beneficio , Epilepsia/inducido químicamente , Epilepsia/tratamiento farmacológico , Humanos , Lamotrigina/uso terapéutico , Estudios Prospectivos , Triazinas/uso terapéuticoRESUMEN
Ardisia bullata G. H. Huang & G. Hao is a small shrubs of Primulaceae. It is only distributed in Hainan provinces of China. It is a plant medicinal value. There is no study on the genome of A. bullata so far. Here, we report and characterize the complete plastid genome sequence of A. bullata in an order to provide genomic resources useful for promoting its conservation. The complete chloroplast genome of A. bullata is 160,176 bp in length with a typical quadripartite structure, consisting of a large single-copy region (LSC, 89,710 bp), a single-copy region (SSC, 18,357 bp), and a pair of inverted repeats (IRs, 26,054 bp). There are 133 genes annotated, including 83 unique protein-coding genes, eight unique ribosomal RNA genes, and 37 transfer RNA genes. The overall G/C content in the plastome of A. bullata is 36.0%. The complete plastome sequence of A. bullata will provide a useful resource for the conservation genetics of this species as well as for phylogenetic studies in Apocynaceae.
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BACKGROUND: The pharmacokinetics of lamotrigine (LTG) is complex and varies significantly among individuals, especially among children. Therefore, this study aimed to establish a population pharmacokinetic (PPK) model of LTG in Chinese children with epilepsy and to comprehensively evaluate the effects of genetic variations in drug-metabolizing enzymes, transporters, and a transcriptional regulator on LTG pharmacokinetics. METHODS: Three hundred eighty-five steady-state plasma concentrations were obtained from 179 children (age 10.72 ± 3.05 years and body weight 46.23 ± 17.77 kg) with epilepsy during therapeutic drug monitoring. These patients were divided into the PPK-model group (n = 121) and the PPK-validation group (n = 58) and were genotyped for UGT1A4, UGT2B7, ABCB1, ABCG2, SLC22A1, and HNF4α. PPK analysis was performed by nonlinear mixed effects modeling. RESULTS: In the final model, apparent clearance (CL/F) of LTG was estimated to be 1.48 L/h; 500 mg valproic acid, oxcarbazepine, and UGT2B7-161TT genotype changed the CL/F by -46.2, +31.1, and -21.8%, respectively. Body weight was also identified as a significant covariate affecting LTG CL/F. CONCLUSIONS: A PPK-pharmacogenetic model of LTG in Chinese children with epilepsy was successfully established with nonlinear mixed effects modeling. Genotyping for UGT2B7-161C>T may be useful in titrating the optimal LTG dose.
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Transportadoras de Casetes de Unión a ATP/genética , Pueblo Asiatico/genética , Epilepsia/genética , Factor Nuclear 4 del Hepatocito/genética , Inactivación Metabólica/genética , Lamotrigina/farmacocinética , Farmacogenética/métodos , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/farmacología , Niño , Interacciones Farmacológicas , Epilepsia/sangre , Genotipo , Humanos , Lamotrigina/sangre , Modelos Biológicos , Oxcarbazepina/farmacología , Ácido Valproico/farmacologíaRESUMEN
PURPOSE: The aims of this study were to develop a population pharmacokinetic (PPK) model of lamotrigine (LTG) in Chinese epileptic children by using nonlinear mixed effects modeling (NONMEM) and to investigate the effects of valproic acid (VPA) and genetic polymorphisms of the major metabolizing enzymes (UGT1A4, UGT2B7) on the pharmacokinetics of LTG. METHODS: A total of 182 epileptic children who were treated with LTG as monotherapy or as part of combination therapy were included in this study as the model group, and 61 patients were included as the validation group. The steady-state serum trough concentrations of LTG and VPA were determined using a high-performance liquid chromatography method and fluorescence polarization immunoassay, respectively. Patients were genotyped for three single nucleotide polymorphisms (UGT1A4 142T>G, UGT2B7 -161C>T, and UGT2B7 802C>T). PPK analysis was performed with NONMEM using first-order absorption and elimination. Bootstrap, normalized prediction distribution errors and external evaluations were performed to determine the stability and predictive performance of the model. RESULTS: For the final model, the oral clearance (CL/F) of LTG was estimated to be 0.705 L/h with inter-individual variability (IIV) of 21.3%. The estimates generated by NONMEM indicated that the LTG CL/F was significantly influenced by patient body weight (increased with an exponent of 0.574) and VPA concentration (decreased with linearity of 0.273 with co-administration). However, no significant effects of UGT1A4 or UGT2B7 polymorphisms on LTG CL/F were noted in this population of Chinese children. CONCLUSION: This study confirms the interaction of LTG with VPA, which likely depends on VPA concentration. The LTG PPK model developed in this study could be useful for individualizing LTG dosage regimens in pediatric patients receiving combination therapy, especially therapy that includes VPA.
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Anticonvulsivantes/farmacocinética , Modelos Biológicos , Triazinas/farmacocinética , Ácido Valproico/farmacocinética , Adolescente , Anticonvulsivantes/sangre , Pueblo Asiatico/genética , Niño , Preescolar , Quimioterapia Combinada , Epilepsia/sangre , Epilepsia/tratamiento farmacológico , Epilepsia/genética , Femenino , Genotipo , Glucuronosiltransferasa/genética , Humanos , Lamotrigina , Masculino , Dinámicas no Lineales , Polimorfismo de Nucleótido Simple , Triazinas/sangre , Ácido Valproico/sangreRESUMEN
OBJECTIVE: To compare the detection effect of Legionella pollution in spring water by three methods, namely traditional plating method, fluorescent quantitation PCR method and ethidium monoazide (EMA) fluorescent quantitation PCR method. METHODS: Every month (except May), we collected 11 water samples from the 5 selected hot spring pools in one hot spring resort in Beijing in 2011. A total of 121 water samples were collected, and then were detected by the above three methods qualitatively and quantitatively. RESULTS: In our study, the Legionella pollution rate was separately 74.4% (90/121), 100.0% (121/121) and 100.0% (121/121) by the above three methods. The quantitative value of Legionella in the 121 water samples detected by the three methods were around 0.10-216.00 colony-forming units (CFU)/ml, 1.47-1557.75 gene units (GU)/ml and 0.20-301.69 GU/ml, respectively. The median (25th and 75th percentiles) was 75.30 (32.51-192.10) GU/ml, 36.46 (16.08-91.21) GU/ml and 5.30 (0.00-33.70) CFU/ml, respectively. The difference in the quantitative value of Legionella detected by the three methods showed statistical significance (χ(2) = 187.900, P < 0.01). The quantitative value of Legionella detected by fluorescent quantitation PCR method was the highest, followed by the value Legionella detected by EMA-fluorescent quantitation PCR method and traditional plating method. CONCLUSION: The sensitivity of the PCR methods was higher than traditional plating method, in detecting Legionella pollution in spring water, especially the EMA- fluorescent quantitation PCR method, which was more suitable for detecting Legionella in water.
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Monitoreo del Ambiente/métodos , Manantiales de Aguas Termales/microbiología , Legionella/aislamiento & purificación , Microbiología del Agua , Legionella/clasificación , Técnicas MicrobiológicasRESUMEN
BACKGROUND: Legionella is the causative agent of Legionnaires' disease, and hot springs are a major source of outbreaks of this disease. It is important from a public health perspective to survey hot spring environments for the presence of Legionella. METHODS: Prospective surveillance of the extent of Legionella pollution was conducted at three hot spring recreational areas in Beijing, China in 2011. Pulsed-field gel electrophoresis (PFGE) and sequence-based typing (SBT) were used to describe the genetic polymorphism of isolates. The intracellular growth ability of the isolates was determined by interacting with J774 cells and plating the dilutions onto BCYE agar plates. RESULTS: Overall, 51.9% of spring water samples showed Legionella-positive, and their concentrations ranged from 1 CFU/liter to 2,218 CFU/liter. The positive rates of Legionella were significantly associated with a free chlorine concentration of ≥0.2 mg/L, urea concentration of ≥0.05 mg/L, total microbial counts of ≥400 CFU/ml and total coliform of ≥3 MPN/L (p<0.01). The Legionella concentrations were significantly associated with sample temperature, pH, total microbial counts and total coliform (p<0.01). Legionella pneumophila was the most frequently isolated species (98.9%), and the isolated serogroups included serogroups 3 (25.3%), 6 (23.4%), 5 (19.2%), 1 (18.5%), 2 (10.2%), 8 (0.4%), 10 (0.8%), 9 (1.9%) and 12 (0.4%). Two hundred and twenty-eight isolates were analyzed by PFGE and 62 different patterns were obtained. Fifty-seven L. pneumophila isolates were selected for SBT analysis and divided into 35 different sequence types with 5 main clonal groups. All the 57 isolates had high intracellular growth ability. CONCLUSIONS: Our results demonstrated high prevalence and genetic polymorphism of Legionella in springs in Beijing, China, and the SBT and intracellular growth assay results suggested that the Legionella isolates of hot spring environments were pathogenic. Improved control and prevention strategies are urgently needed.
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Variación Genética , Manantiales de Aguas Termales/microbiología , Legionella/genética , China , Análisis por Conglomerados , Electroforesis en Gel de Campo Pulsado , Legionella/clasificación , Legionella/aislamiento & purificación , Vigilancia en Salud Pública , Recreación , Estaciones del Año , Microbiología del Agua , Calidad del AguaRESUMEN
OBJECTIVE: To investigate the effectiveness and surgical skills of microsurgical repair of radial nerve deep branch injury. METHODS: Between March 2001 and February 2011, 49 cases of radial nerve deep branch injury were treated by microsurgical technique. There were 40 males and 9 females with an average age of 32 years (range, 19-58 years), including 13 cases of knife-cut injury, 9 cases of electric-saw injury, 7 cases of dagger-stab injury, 6 cases of glass-cut injury, 5 cases of iatrogenic injury, 4 cases of Monteggia fracture, 3 cases of nailgun injury, and 2 cases of crush injury of the forearm complicated by fracture of the proximal radius. The disease duration ranged from 3 hours to 3 years and 8 months (mean, 4.9 months). The sites of injury were at front of supinator tube in 15 cases, in the supinator tube in 23 cases, and at back of supinator tube in 11 cases. One-stage repair was performed by end-to-end suture in 21 cases, including 9 cases of epineurial neurorrhaphy and 12 cases of perineurial neurorrhaphy; two-stage repair was performed in 28 cases, including 26 cases of sural nerve graft and 2 cases of neurolysis. RESULTS: Postoperative wounds primarily healed. All patients were followed up 21.5 months on average (range, 12-39 months). At last follow-up, in 21 cases of one-stage repair, the muscle strength of the extensor pollicis longus was level 5 in 13 cases, and level 4 in 8 cases; in 28 cases of two-stage repair, the muscle strength of the extensor pollicis longus was level 5 in 2 cases, level 4 in 21 cases, level 3 in 4 cases, and level 2 in 1 case; and significant difference was found (Z=-5.340, P=0.000). In 9 cases undergoing epineurial neurorrhaphy at one-stage repair, the muscle strength of the extensor pollicis longus was level 5 in 3 cases, and level 4 in 6 cases; in 12 cases undergoing perineurial neurorrhaphy at one-stage repair, the muscle strength of the extensor pollicis longus was level 5 in 10 cases, and level 4 in 2 cases; and significant difference was found (Z=-2.279, P=0.023). In 26 cases undergoing nerve graft at two-stage repair, the muscle strength of the extensor pollicis longus was level 5 in 2 cases, level 4 in 20 cases, level 3 in 3 cases, and level 2 in 1 case; in 2 cases undergoing neurolysis at two-stage repair, the muscle strength of the extensor pollicis longus was level 4 in 1 case and level 3 in 1 case; and no significant difference was found (Z=-1.117, P=0.264). According to the upper arm function assessment criterion issued by Hand Surgery Association of Chinese Medicine Association, the results were excellent in 18 cases, good in 3 cases in one-stage repair patients; excellent in 2 cases, good in 21 cases, fair in 4 cases, and poor in 1 case in two-stage repair patients; and there was significant difference (Z=-5.340, P=0.000). CONCLUSION: Microsurgical one-stage repair of radial nerve deep branch injury can obtain better effectiveness than two-stage repair by nerve graft, and perineurial neurorrhaphy is significantly better than epineurial neurorrhaphy.
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Traumatismos de la Mano/cirugía , Microcirugia/métodos , Procedimientos Neuroquirúrgicos/métodos , Nervio Radial/lesiones , Nervio Sural/trasplante , Adulto , Anastomosis Quirúrgica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiología , Músculo Esquelético/cirugía , Nervio Radial/anatomía & histología , Nervio Radial/cirugía , Recuperación de la Función/fisiología , Estudios Retrospectivos , Pulgar/fisiología , Resultado del Tratamiento , Muñeca/fisiología , Adulto JovenRESUMEN
Composite coatings with hydroxyapatite (HA), octacalcium phosphate (OCP) in electrochemical deposition (ED) layers and MgO, Mg3 (PO4 )2 in microarc oxidation (MAO) layers were prepared by ED and MAO on Mg-Zn-Ca alloy to improve the corrosion resistance and bone response. Substrates and coated samples were implanted in the femur shaft of rabbits to observe in vivo degradation behavior during 50 weeks. Results showed that the degradation rate of the substrates was much faster than the coated at 8, 12 weeks and became close to the coated at 18 weeks postoperatively. The composite coatings prevented the substrate from rapid release of magnesium ions at the interface and gradually degraded at the same time. The composite coatings induced more newly formed bone tissue and faster bone response. Overall, reduced degradation rate and improved bone response were achieved by the composite coatings. Thus, the composite coatings on Mg-Zn-Ca alloy are promising for clinical application in the future.
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Implantes Absorbibles , Aleaciones , Sustitutos de Huesos , Materiales Biocompatibles Revestidos , Técnicas Electroquímicas , Aleaciones/química , Aleaciones/farmacología , Animales , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Calcio/química , Calcio/farmacología , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Durapatita/química , Durapatita/farmacología , Magnesio/química , Magnesio/farmacología , Oxidación-Reducción , Conejos , Propiedades de Superficie , Zinc/química , Zinc/farmacologíaRESUMEN
In present paper, an in vivo study was carried out on uncoated and calcium-deficient hydroxyapatite (Ca-def HA) coated Mg-Zn-Ca alloy to investigate the effect of Ca-def HA coating on the degradation behavior and bone response of magnesium substrate. Magnesium alloy rods were implanted into rabbit femora and evaluated during 24 weeks implantation. The characterization of both implants indicates that in vivo degradation of the Ca-def HA coating and magnesium substrate occurs almost simultaneously, and in vivo valid life of the coating is about 8 weeks, after that the degradation rate of the coated implants increases obviously. The main reasons for the Ca-def HA coating degradation can be attributed to its reaction with body fluid and the substitution of Mg(2+) ions in Ca-def HA. Histopathological examinations show that the Ca-def HA coating has good osteoconductivity and is in favor of the formation of more new bone on the surface of magnesium alloy. So the Ca-def HA coating could not only slow down in vivo degradation of magnesium alloy but also improve its bone response.