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1.
Chin Med J (Engl) ; 137(4): 431-440, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-37690994

RESUMEN

BACKGROUND: Findings on the association of genetic factors and colorectal cancer (CRC) survival are limited and inconsistent, and revealing the mechanism underlying their prognostic roles is of great importance. This study aimed to explore the relationship between functional genetic variations and the prognosis of CRC and further reveal the possible mechanism. METHODS: We first systematically performed expression quantitative trait locus (eQTL) analysis using The Cancer Genome Atlas (TCGA) dataset. Then, the Kaplan-Meier analysis was used to filter out the survival-related eQTL target genes of CRC patients in two public datasets (TCGA and GSE39582 dataset from the Gene Expression Omnibus database). The seven most potentially functional eQTL single nucleotide polymorphisms (SNPs) associated with six survival-related eQTL target genes were genotyped in 907 Chinese CRC patients with clinical prognosis data. The regulatory mechanism of the survival-related SNP was further confirmed by functional experiments. RESULTS: The rs71630754 regulating the expression of endoplasmic reticulum aminopeptidase 1 ( ERAP1 ) was significantly associated with the prognosis of CRC (additive model, hazard ratio [HR]: 1.43, 95% confidence interval [CI]: 1.08-1.88, P = 0.012). The results of dual-luciferase reporter assay and electrophoretic mobility shift assay showed that the A allele of the rs71630754 could increase the binding of transcription factor 3 (TCF3) and subsequently reduce the expression of ERAP1 . The results of bioinformatic analysis showed that lower expression of ERAP1 could affect the tumor immune microenvironment and was significantly associated with severe survival outcomes. CONCLUSION: The rs71630754 could influence the prognosis of CRC patients by regulating the expression of the immune-related gene ERAP1 . TRIAL REGISTRATION: No. NCT00454519 ( https://clinicaltrials.gov/ ).


Asunto(s)
Neoplasias Colorrectales , Polimorfismo de Nucleótido Simple , Humanos , Pronóstico , Genotipo , Polimorfismo de Nucleótido Simple/genética , Sitios de Carácter Cuantitativo , Microambiente Tumoral , Aminopeptidasas/genética , Aminopeptidasas/metabolismo , Antígenos de Histocompatibilidad Menor/genética
2.
Nat Commun ; 14(1): 7900, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38036550

RESUMEN

Left ventricular regional wall thickness (LVRWT) is an independent predictor of morbidity and mortality in cardiovascular diseases (CVDs). To identify specific genetic influences on individual LVRWT, we established a novel deep learning algorithm to calculate 12 LVRWTs accurately in 42,194 individuals from the UK Biobank with cardiac magnetic resonance (CMR) imaging. Genome-wide association studies of CMR-derived 12 LVRWTs identified 72 significant genetic loci associated with at least one LVRWT phenotype (P < 5 × 10-8), which were revealed to actively participate in heart development and contraction pathways. Significant causal relationships were observed between the LVRWT traits and hypertrophic cardiomyopathy (HCM) using genetic correlation and Mendelian randomization analyses (P < 0.01). The polygenic risk score of inferoseptal LVRWT at end systole exhibited a notable association with incident HCM, facilitating the identification of high-risk individuals. The findings yield insights into the genetic determinants of LVRWT phenotypes and shed light on the biological basis for HCM etiology.


Asunto(s)
Cardiomiopatía Hipertrófica , Estudio de Asociación del Genoma Completo , Humanos , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Cardiomiopatía Hipertrófica/genética , Corazón , Ventrículos Cardíacos/patología , Fenotipo
3.
Front Plant Sci ; 14: 1207078, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37915509

RESUMEN

Thinopyrum intermedium (2n=6x=42, StStJrJrJvsJvs) is resistant or tolerant to biotic and abiotic stresses, making it suitable for developing perennial crops and forage. Through five cycles of selection, we developed 24 perennial wheatgrass lines, designated 19HSC-Q and 20HSC-Z, by crossing wheat-Th. intermedium partial amphiploids with Th. intermedium. The cold resistance, morphological performance, chromosome composition, and yield components of these perennial lines were investigated from 2019 to 2022. Six lines of 19HSC-Q had higher 1,000-kernel weight, grains per spike, and tiller number than Th. intermedium, as well as surviving -30°C in winter. Lines 19HSC-Q14, 19HSC-Q18, and 19HSC-Q20 had the best performances for grain number per spike and 1,000-kernel weight. The 20HSC-Z lines, 20HSC-Z1, 20HSC-Z2, and 20HSC-Z3, were able to survive in the cold winter in Harbin and had been grown for two years. Sequential multicolor GISH analysis revealed that the Jvs subgenome of Th. intermedium were divided into two karyotypes, three pairs of type-I Jvs chromosomes and four pairs of type-II Jvs chromosomes. Both Th. intermedium and the 24 advanced perennial wheatgrass lines had similar chromosome compositions, but the translocations among subgenome chromosomes were detected in some lines with prominent agronomic traits, such as 19HSC-Q11, 19HSC-Q14, 19HSC-Q18, 19HSC-Q20, and the three 20HSC-Z lines. The chromosome aberrations were distinguished into two types: the large fragment translocation with St-Jr, Jvs-St, Jr-IIJvs, and Jvs-Jr and the small fragment introgression of Jr-St, St-IJvs, and Jvs-Jr. These chromosomal variations can be used to further analyze the relationship between the subgenomes and phenotypes of Th. intermedium. The results of this study provide valuable materials for the next selection cycle of cold-resistant perennial wheatgrass.

4.
Nat Commun ; 14(1): 5958, 2023 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-37749132

RESUMEN

Genome-wide association studies have identified numerous variants associated with human complex traits, most of which reside in the non-coding regions, but biological mechanisms remain unclear. However, assigning function to the non-coding elements is still challenging. Here we apply Activity-by-Contact (ABC) model to evaluate enhancer-gene regulation effect by integrating multi-omics data and identified 544,849 connections across 20 cancer types. ABC model outperforms previous approaches in linking regulatory variants to target genes. Furthermore, we identify over 30,000 enhancer-gene connections in colorectal cancer (CRC) tissues. By integrating large-scale population cohorts (23,813 cases and 29,973 controls) and multipronged functional assays, we demonstrate an ABC regulatory variant rs4810856 associated with CRC risk (Odds Ratio = 1.11, 95%CI = 1.05-1.16, P = 4.02 × 10-5) by acting as an allele-specific enhancer to distally facilitate PREX1, CSE1L and STAU1 expression, which synergistically activate p-AKT signaling. Our study provides comprehensive regulation maps and illuminates a single variant regulating multiple genes, providing insights into cancer etiology.


Asunto(s)
Estudio de Asociación del Genoma Completo , Neoplasias , Humanos , Secuencias Reguladoras de Ácidos Nucleicos , Regulación de la Expresión Génica , Mapeo Cromosómico , Alelos , Polimorfismo de Nucleótido Simple , Predisposición Genética a la Enfermedad , Elementos de Facilitación Genéticos/genética , Neoplasias/genética , Proteínas del Citoesqueleto/genética , Proteínas de Unión al ARN/genética
5.
Cancer Res ; 83(21): 3650-3666, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37669142

RESUMEN

Alternative polyadenylation (APA) is emerging as a major mechanism of posttranscriptional regulation. APA can impact the development and progression of cancer, suggesting that the genetic determinants of APA might play an important role in regulating cancer risk. Here, we depicted a pan-cancer atlas of human APA quantitative trait loci (apaQTL), containing approximately 0.7 million apaQTLs across 32 cancer types. Systematic multiomics analyses indicated that cancer apaQTLs could contribute to APA regulation by altering poly(A) motifs, RNA-binding proteins (RBP), and chromatin regulatory elements and were preferentially enriched in genome-wide association studies (GWAS)-identified cancer susceptibility loci. Moreover, apaQTL-related genes (aGene) were broadly related to cancer signaling pathways, high mutational burden, immune infiltration, and drug response, implicating their potential as therapeutic targets. Furthermore, apaQTLs were mapped in Chinese colorectal cancer tumor tissues and then screened for functional apaQTLs associated with colorectal cancer risk in 17,789 cases and 19,951 controls using GWAS-ChIP data, with independent validation in a large-scale population consisting of 6,024 cases and 10,022 controls. A multi-ancestry-associated apaQTL variant rs1020670 with a C>G change in DNM1L was identified, and the G allele contributed to an increased risk of colorectal cancer. Mechanistically, the risk variant promoted aberrant APA and facilitated higher usage of DNM1L proximal poly(A) sites mediated by the RBP CSTF2T, which led to higher expression of DNM1L with a short 3'UTR. This stabilized DNM1L to upregulate its expression, provoking colorectal cancer cell proliferation. Collectively, these findings generate a resource for understanding APA regulation and the genetic basis of human cancers, providing insights into cancer etiology. SIGNIFICANCE: Cancer risk is mediated by alternative polyadenylation quantitative trait loci, including the rs1020670-G variant that promotes alternative polyadenylation of DNM1L and increases colorectal cancer risk.


Asunto(s)
Neoplasias Colorrectales , Estudio de Asociación del Genoma Completo , Humanos , Poliadenilación/genética , Regulación de la Expresión Génica , Sitios de Carácter Cuantitativo , Neoplasias Colorrectales/genética , Regiones no Traducidas 3'/genética
6.
Gastroenterology ; 165(5): 1151-1167, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37541527

RESUMEN

BACKGROUND & AIMS: Dysregulation of alternative splicing is implicated in many human diseases, and understanding the genetic variation underlying transcript splicing is essential to dissect the molecular mechanisms of cancers. We aimed to provide a comprehensive functional dissection of splicing quantitative trait loci (sQTLs) in cancer and focus on elucidating its distinct role in colorectal cancer (CRC) mechanisms. METHODS: We performed a comprehensive sQTL analysis to identify genetic variants that control messenger RNA splicing across 33 cancer types from The Cancer Genome Atlas and independently validated in our 154 CRC tissues. Then, large-scale, multicenter, multi-ethnic case-control studies (34,585 cases and 76,023 controls) were conducted to examine the association of these sQTLs with CRC risk. A series of biological experiments in vitro and in vivo were performed to investigate the potential mechanisms of the candidate sQTLs and target genes. RESULTS: The molecular characterization of sQTL revealed its distinct role in cancer susceptibility. Tumor-specific sQTL further showed better response to cancer development. In addition, functionally informed polygenic risk score highlighted the potentiality of sQTLs in the CRC prediction. Complemented by large-scale population studies, we identified that the risk allele (T) of a multi-ancestry-associated sQTL rs61746794 significantly increased the risk of CRC in Chinese (odds ratio, 1.20; 95% CI, 1.12-1.29; P = 8.82 × 10-7) and European (odds ratio, 1.11; 95% CI, 1.07-1.16; P = 1.13 × 10-7) populations. rs61746794-T facilitated PRMT7 exon 16 splicing mediated by the RNA-binding protein PRPF8, thus increasing the level of canonical PRMT7 isoform (PRMT7-V2). Overexpression of PRMT7-V2 significantly enhanced the growth of CRC cells and xenograft tumors compared with PRMT7-V1. Mechanistically, PRMT7-V2 functions as an epigenetic writer that catalyzes the arginine methylation of H4R3 and H3R2, subsequently regulating diverse biological processes, including YAP, AKT, and KRAS pathway. A selective PRMT7 inhibitor, SGC3027, exhibited antitumor effects on human CRC cells. CONCLUSIONS: Our study provides an informative sQTLs resource and insights into the regulatory mechanisms linking splicing variants to cancer risk and serving as biomarkers and therapeutic targets.

7.
Arch Toxicol ; 97(7): 2015-2028, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37245169

RESUMEN

Although genome-wide association studies (GWASs) have identified over 100 colorectal cancer (CRC) risk loci, an understanding of causal genes or risk variants and their biological functions in these loci remain unclear. Recently, genomic loci 10q26.12 with lead SNP rs1665650 was identified as an essential CRC risk loci of Asian populations. However, the functional mechanism of this region has not been fully clarified. Here, we applied an RNA interfering-based on-chip approach to screen for the genes essential for cell proliferation in the CRC risk loci 10q26.12. Notably, HSPA12A had the most significant effect among the identified genes and functioned as a crucial oncogene facilitating cell proliferation. Moreover, we conducted an integrative fine-mapping analysis to identify putative casual variants and further explored their association with CRC risk in a large-scale Chinese population consisting of 4054 cases and 4054 controls and also independently validated in 5208 cases and 20,832 controls from the UK biobank cohort. We identified a risk SNP rs7093835 in the intron of HSPA12A that was significantly associated with an increased risk of CRC (OR 1.23, 95% CI 1.08-1.41, P = 1.92 × 10-3). Mechanistically, the risk variant could facilitate an enhancer-promoter interaction mediated by the transcriptional factor (TF) GRHL1 and ultimately upregulate HSPA12A expression, which provides functional evidence to support our population findings. Collectively, our study reveals the important role of HSPA12A in CRC development and illustrates a novel enhancer-promoter interaction module between HSPA12A and its regulatory elements rs7093835, providing new insights into the etiology of CRC.


Asunto(s)
Neoplasias Colorrectales , Estudio de Asociación del Genoma Completo , Humanos , Predisposición Genética a la Enfermedad , Regiones Promotoras Genéticas , Riesgo , Neoplasias Colorrectales/genética , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Proteínas HSP70 de Choque Térmico/genética
8.
Int J Cancer ; 153(3): 499-511, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37087737

RESUMEN

Previous investigations mainly focused on the associations of dietary fatty acids with colorectal cancer (CRC) risk, which ignored gene-environment interaction and mechanisms interpretation. We conducted a case-control study (751 cases and 3058 controls) and a prospective cohort study (125 021 participants) to explore the associations between dietary fatty acids, genetic risks, and CRC. Results showed that high intake of saturated fatty acid (SFA) was associated with a higher risk of CRC than low SFA intake (HR =1.22, 95% CI:1.02-1.46). Participants at high genetic risk had a greater risk of CRC with the HR of 2.48 (2.11-2.91) than those at low genetic risk. A multiplicative interaction of genetic risk and SFA intake with incident CRC risk was found (PInteraction = 7.59 × 10-20 ), demonstrating that participants with high genetic risk and high SFA intake had a 3.75-fold greater risk of CRC than those with low genetic risk and low SFA intake. Furthermore, incorporating PRS and SFA into traditional clinical risk factors improved the discriminatory accuracy for CRC risk stratification (AUC from 0.706 to 0.731). Multi-omics data showed that exposure to SFA-rich high-fat dietary (HFD) can responsively induce epigenome reprogramming of some oncogenes and pathological activation of fatty acid metabolism pathway, which may contribute to CRC development through changes in gut microbiomes, metabolites, and tumor-infiltrating immune cells. These findings suggest that individuals with high genetic risk of CRC may benefit from reducing SFA intake. The incorporation of SFA intake and PRS into traditional clinical risk factors will help improve high-risk sub-populations in individualized CRC prevention.


Asunto(s)
Neoplasias Colorrectales , Grasas de la Dieta , Humanos , Estudios Prospectivos , Estudios de Casos y Controles , Grasas de la Dieta/efectos adversos , Factores de Riesgo , Ácidos Grasos/efectos adversos , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inducido químicamente
9.
Cancer Res ; 82(19): 3449-3456, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-35972351

RESUMEN

Microorganisms are commonly detected in tumor tissues, and the species and abundance have been reported to affect cancer initiation, progression, and therapy. Host genetics have been associated with gut microbial abundances, while the relationships between genetic variants and the cancer microbiome still require systematic interrogation. Therefore, identification of cancer microbiome quantitative trait loci (mbQTL) across cancer types might elucidate the contributions of genetic variants to tumor development. Using genotype data from The Cancer Genome Atlas and microbial abundance levels from Kraken-derived data, we developed a computational pipeline to identify mbQTLs in 32 cancer types. This study systematically identified 38,660 mbQTLs across cancers, ranging 50 in endometrial carcinoma to 3,133 in thyroid carcinoma. Furthermore, a strong enrichment of mbQTLs was observed among transcription factor binding sites and chromatin regulatory elements, such as H3K27ac. Notably, mbQTLs were significantly enriched in cancer genome-wide association studies (GWAS) loci and explained an average of 2% for cancer heritability, indicating that mbQTLs could provide additional insights into cancer etiology. Correspondingly, 24,443 mbQTLs overlapping with GWAS linkage disequilibrium regions were identified. Survival analyses identified 318 mbQTLs associated with patient overall survival. Moreover, we uncovered 135,248 microbiome-immune infiltration associations and 166,603 microbiome-drug response associations that might provide clues for microbiome-based biomarkers. Finally, a user-friendly database, Cancer-mbQTL (http://canmbqtl.whu.edu.cn/#/), was constructed for users to browse, search, and download data of interest. This study provides a valuable resource for investigating the roles of genetics and microorganisms in human cancer. SIGNIFICANCE: This study provides insights into the host-microbiome interactions for multiple cancer types, which could help the research community understand the effects of inherited variants in tumorigenesis and development.


Asunto(s)
Microbiota , Neoplasias , Cromatina , Estudio de Asociación del Genoma Completo , Humanos , Microbiota/genética , Neoplasias/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Factores de Transcripción/genética
10.
Cancer Res ; 82(11): 2084-2096, 2022 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-35363263

RESUMEN

Understanding the genetic variation underlying transcript splicing is essential for fully dissecting the molecular mechanisms of common diseases. The available evidence from splicing quantitative trait locus (sQTL) studies using pancreatic ductal adenocarcinoma (PDAC) tissues have been limited to small sample sizes. Here we present a genome-wide sQTL analysis to identify SNP that control mRNA splicing in 176 PDAC samples from TCGA. From this analysis, 16,175 sQTLs were found to be significantly enriched in RNA-binding protein (RBP) binding sites and chromatin regulatory elements and overlapped with known loci from PDAC genome-wide association studies (GWAS). sQTLs and expression quantitative trait loci (eQTL) showed mostly nonoverlapping patterns, suggesting sQTLs provide additional insights into the etiology of disease. Target genes affected by sQTLs were closely related to cancer signaling pathways, high mutational burden, immune infiltration, and pharmaceutical targets, which will be helpful for clinical applications. Integration of a large-scale population consisting of 2,782 patients with PDAC and 7,983 healthy controls identified an sQTL variant rs1785932-T allele that promotes alternative splicing of ELP2 exon 6 and leads to a lower level of the ELP2 full-length isoform (ELP2_V1) and a higher level of a truncated ELP2 isoform (ELP2_V2), resulting in decreased risk of PDAC [OR = 0.83; 95% confidence interval (CI), 0.77-0.89; P = 1.16 × 10-6]. The ELP2_V2 isoform functioned as a potential tumor suppressor gene, inhibiting PDAC cell proliferation by exhibiting stronger binding affinity to JAK1/STAT3 than ELP2_V1 and subsequently blocking the pathologic activation of the phosphorylated STAT3 (pSTAT3) pathway. Collectively, these findings provide an informative sQTL resource and insights into the regulatory mechanisms linking splicing variants to PDAC risk. SIGNIFICANCE: In pancreatic cancer, splicing quantitative trait loci analysis identifies a rs1785932 variant that contributes to decreased risk of disease by influencing ELP2 mRNA splicing and blocking the STAT3 oncogenic pathway.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Empalme Alternativo , Carcinoma Ductal Pancreático/genética , Estudio de Asociación del Genoma Completo/métodos , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Neoplasias Pancreáticas/genética , Polimorfismo de Nucleótido Simple , Isoformas de Proteínas/genética , Empalme del ARN/genética , ARN Mensajero
11.
ACS Appl Mater Interfaces ; 13(24): 29008-29020, 2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34121382

RESUMEN

In recent years, ionic conductive hydrogels have shown great potential for application in flexible sensors, energy storage devices, and actuators. However, developing facile and effective methods for fabricating such hydrogels remains a great challenge, especially for hydrogels that retain their properties in extreme environmental conditions, such as at subzero temperatures or storage in open-air conditions. Herein, a water-miscible ionic liquid (IL), such as 1-ethyl-3-methylimidazolium acetate (EMImAc), was introduced to form an IL/water binary solvent system for poly(vinyl alcohol) (PVA) to create ionic conductive PVA hydrogels. The physically crosslinked PVA/EMImAc/H2O hydrogels showed better mechanical properties and transparency than the traditional PVA hydrogel prepared by the freeze-thaw method due to the formation of homogeneous and small PVA microcrystals in the EMImAc/H2O binary solvent system. More importantly, the PVA/EMImAc/H2O hydrogel exhibited significant anti-freezing and water-retaining properties because of the presence of the IL. The hydrogels remained flexible and conductive at temperatures as low as -50 °C and retained more than 90% of their weight after storage in open-air conditions for 2 weeks. In addition, the thermal stability of the hydrogel could be increased to 95 °C through the addition of Mg(II) ions. A multimodal sensor based on the PVA/EMImAc/H2O/Mg(II) hydrogel showed high sensitivity and a quick response to changes in pressure, strain, and temperature, with both long-term stability and a wide working temperature range. This study may open a new route for the fabrication of functional PVA-based hydrogel electrolytes and provide a practical pathway for their use in multifunctional electronic and sensory device applications.

12.
PLoS One ; 15(12): e0243555, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33301450

RESUMEN

OBJECTIVE: To measure the situation of the non-prescription sale of antibiotics and the service quality of community pharmacies in Guangzhou, China. METHODS: A simulated client method was conducted to estimate the non-prescription sale of antibiotics and service quality based on scenarios about adult acute upper respiratory tract infection in 2019. A total of 595 community pharmacies from 11 districts were investigated in Guangzhou, China. We used binary logistic regression to evaluate the factors associated with the non-prescription sale of antibiotics. RESULTS: The proportion of non-prescription dispensing of antibiotics was 63.1% in Guangzhou, China, with a higher incidence of antibiotic dispensing without prescription in outer districts (69.3%). Cephalosporin (44.1%) and Amoxicillin (39.0%) were sold more often than other antibiotics. Chain pharmacies had better performance on the prescription sale of antibiotics and service quality. Traditional Chinese medicine was commonly recommended by pharmacy staff. CONCLUSION: Since the non-prescription sale of antibiotics is prevalent in Guangzhou, effective solutions should be determined. Strengthened public awareness and regulatory system innovation are needed.


Asunto(s)
Antibacterianos/economía , Servicios Comunitarios de Farmacia/tendencias , Farmacias/tendencias , Amoxicilina/uso terapéutico , Antibacterianos/uso terapéutico , Cefalosporinas/uso terapéutico , China/epidemiología , Comercio , Servicios Comunitarios de Farmacia/economía , Servicios de Salud , Humanos , Farmacias/economía , Farmacéuticos/economía , Infecciones del Sistema Respiratorio/tratamiento farmacológico
13.
ACS Appl Mater Interfaces ; 12(22): 25353-25362, 2020 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-32347700

RESUMEN

Flexible ionic conductive hydrogel is attracting significant interest as it could be one of the crucial components for multifunctional ionotronic devices. However, their features of inevitably drying out without package and freezing at subzero temperatures may greatly limit the applications of conventional hydrogels in specific situations. Here, we present an ionic conductive hydrogel with water retention and freezing tolerance that consists of silk fibroin, ionic liquid, water, and inorganic salt. It is discovered that the ionic liquid serves multiple purposes to prevent water evaporation, decrease the freezing point, provide the essential conductivity of the hydrogel, etc. As a binary mixed solvent, the ionic liquid/water mixture enhances both water retention and freezing tolerance of the hydrogel electrolyte. Based on the silk fibroin (SF)/1-ethyl-3-methylimidazolium acetate (EMImAc)/H2O/KCl hydrogel electrolyte, the flexible fiberlike supercapacitor could still function well at a temperature as low as -50 °C and after being stored in the open air for a long time. It is anticipated that this hydrogel will prove useful in developing new applications operating under harsh environments.


Asunto(s)
Fibroínas/química , Hidrogeles/química , Proteínas de Insectos/química , Agua/química , Animales , Bombyx/química , Frío , Capacidad Eléctrica , Conductividad Eléctrica , Congelación , Imidazoles/química , Líquidos Iónicos , Cloruro de Potasio/química , Resistencia a la Tracción
14.
Mater Sci Eng C Mater Biol Appl ; 41: 196-205, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24907752

RESUMEN

A multifunctional magnetic mesoporous bioactive glass (MMBG) has been widely used for a drug delivery system, but its biological properties have been rarely reported. Herein, the effects of mesopores and Fe3O4 nanoparticles on drug loading-release property, bactericidal property and biocompatibility have been investigated by using mesoporous bioactive glass (MBG) and non-mesoporous bioactive glass (NBG) as control samples. Both MMBG and MBG have better drug loading efficiency than NBG because they possess ordered mesoporous channels, big specific surface areas and high pore volumes. As compared with MBG, the Fe3O4 nanoparticles in MMBG not only provide magnetic property, but also improve sustained drug release property. For gentamicin-loaded MMBG (Gent-MMBG), the sustained release of gentamicin and the Fe3O4 nanoparticles minimize bacterial adhesion significantly and prevent biofilm formation against Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis). Moreover, the magnetic Fe3O4 nanoparticles in MMBG can promote crucial cell functions such as cell adhesion, spreading and proliferation. The excellent biocompatibility and drug delivery property of MMBG suggest that Gent-MMBG has great potentials for treatment of implant-associated infections.


Asunto(s)
Materiales Biocompatibles/química , Portadores de Fármacos/química , Vidrio/química , Magnetismo , Antibacterianos/química , Antibacterianos/farmacología , Materiales Biocompatibles/metabolismo , Óxido Ferrosoférrico/química , Gentamicinas/química , Gentamicinas/farmacología , Nanopartículas de Magnetita/química , Porosidad , Staphylococcus aureus/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos
15.
J Mater Sci Mater Med ; 24(8): 1951-61, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23695360

RESUMEN

Implant-associated infection remains a difficult medical problem in orthopaedic surgery. Here, we report on the fabrication of gentamicin-loaded mesoporous bioactive glass (Gent-MBG) for use as a controlled antibiotic delivery system to achieve the sustained release of antibiotics in the local sites of bone defects. The high surface area and mesoporous structure of MBG enable higher drug loading efficiency (79-83 %) than non-mesoporous biological glass (NBG) (18-19 %). Gent-MBG exhibits sustained drug release for more than 6 days, and this controlled release of gentamicin significantly inhibits bacterial adhesion and prevents biofilm formation by S. aureus (ATCC25923) and S. epidermidis (ATCC35984). Biocompatibility tests with human bone marrow stromal cells (hBMSCs) indicate that MBG has better biocompatibility than NBG. Therefore, Gent-MBG can be used as a controlled drug delivery system to prevent and/or treat orthopedic peri-implant infections.


Asunto(s)
Antibacterianos/administración & dosificación , Cerámica/síntesis química , Cerámica/farmacología , Portadores de Fármacos/síntesis química , Sistemas de Liberación de Medicamentos , Gentamicinas/administración & dosificación , Antibacterianos/farmacocinética , Antibacterianos/farmacología , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/fisiología , Células Cultivadas , Cerámica/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/instrumentación , Sistemas de Liberación de Medicamentos/métodos , Evaluación Preclínica de Medicamentos , Gentamicinas/farmacocinética , Gentamicinas/farmacología , Humanos , Ensayo de Materiales/métodos , Pruebas de Sensibilidad Microbiana , Microtecnología/métodos , Porosidad , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo
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