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1.
Analyst ; 147(20): 4607-4615, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36124554

RESUMEN

With the advent of hyperspectral Raman imaging technology, especially the rapid and high-resolution imaging schemes, datasets with thousands to millions of spectra are now commonplace. Standard preprocessing and regression methods such as least squares approaches are time consuming and require input from highly trained operators. Here we propose a solution to this analytic bottleneck through a convolutional neural network trained fully on synthetic data and then applied to experimental measurements, including cases where complete spectral information is missing (i.e. an underdetermined model). An advantage of the model is that it combines background correction and regression into a single step, and does not require user-selected parameters. We compare our results with traditional least squares methods, including the popular asymmetric least squares (AsLS) approach. Our results demonstrate that the proposed CNN model boasts less sensitivity to parameter selection, and with a rapid processing speed, with performance equal to or better than comparison methods. The performance is validated on synthetic spectral mixtures, as well as experimentally measured single-vesicle liposome data.


Asunto(s)
Liposomas , Redes Neurales de la Computación
2.
Macromol Rapid Commun ; 39(24): e1800604, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30252976

RESUMEN

The 1,3-dipolar cycloaddition of activated internal alkynes with azides has been developed into an efficient polymerization reaction for constructing functional linear 1,4,5-trisubstitued polytriazoles. However, it is rarely employed for the synthesis of hyperbranched polymers. In this work, metal-free polycycloadditions of tris(3-phenylpropiolate)s (1) and tetraphenylethene-containing diazides (2) are performed in dimethylformamide at 100 °C for 7 and 12 h, producing hyperbranched poly(phenyltriazolylcarboxylate)s (hb-PPTCs) with high molecular weights and satisfactory regioregularities in good yields. The hb-PPTCs have good solubility in common organic solvents and high thermal stability. They are non-emissive in solutions, but emit intensively upon aggregation, showing an aggregation-induced emission effect. Their aggregates can work as fluorescent sensors for explosive detection with high sensitivity. Furthermore, the polymers can be utilized for the fabrication of 2D fluorescent patterns with high resolution by UV irradiation through copper grid masks.


Asunto(s)
Azidas/química , Química Clic/métodos , Fenilpropionatos/química , Polímeros/química , Reacción de Cicloadición , Estructura Molecular , Polimerizacion , Triazoles/química
3.
Zhongguo Zhong Yao Za Zhi ; 42(2): 285-289, 2017 Jan.
Artículo en Zh | MEDLINE | ID: mdl-28948732

RESUMEN

Optimal excipients were screened by studying the effect of different excipients on the hygroscopicity of the extract, testing polysaccharide in the preparation and blood glucose value. Single factor tests were performed with hygroscopicity, formability and fluidity as the indexes, and the moisture content, granule yield and angle of repose were combined with physical characters of the materials to screen the proportioning and dosage of excipients. Then the critical relative humidity of preferred Yinsang granules were measured. The optimum excipients for Yinsang hypoglycemic granules were mulberry leaf paste-microcrystalline cellulose-mactra veneriformis crude polysaccharides (10∶9∶1.67). The obtained granules had good formability and fluidity, which were not easy to absorb moisture for liquefaction, with a critical relative humidity of 73%. This formation process was reasonable and feasible, suitable for industrial production, which can significantly improve hygroscopicity and liquefaction properties of extracts, improve stability of Yinsang granules, and provide reference for screening of excipients for other preparations.


Asunto(s)
Celulosa , Medicamentos Herbarios Chinos/química , Excipientes , Hipoglucemiantes/química , Química Farmacéutica , Tamaño de la Partícula , Polvos , Comprimidos , Humectabilidad
4.
Langmuir ; 31(44): 12054-60, 2015 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-26509287

RESUMEN

A simple and versatile method for the preparation of surfaces to control bacterial adhesion is described. Substrates were first treated with two catechol-based polymerization initiators, one for thermal initiation and one for visible-light photoinitiation. Graft polymerization in sequence of dimethylaminoethyl methacrylate (DMAEMA) and 3-acrylamidebenzene boronic acid (BA) from the surface-bound initiators to form mixed polymer brushes on the substrate was then carried out. The PDMAEMA grafts were thermally initiated and the PBA grafts were visible-light-photoinitiated. Gold, poly(vinyl chloride) (PVC), and poly(dimethylsiloxane) (PDMS) were used as model substrates. X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), and ellipsometry analysis confirmed the successful grafting of PDMAEMA/PBA mixed brushes. We demonstrated that the resulting surfaces showed charge-reversal properties in response to change of pH. The transition in surface charge at a specific pH allowed the surface to be reversibly switched from bacteria-adhesive to bacteria-resistant. At pH 4.5, below the isoelectric points (IEP, pH 5.3) of the mixed brushes, the surfaces are positively charged and the negatively charged Gram-positive S. aureus adheres at high density (2.6 × 10(6) cells/cm(2)) due to attractive electrostatic interactions. Subsequently, upon increasing the pH to 9.0 to give negatively charged polymer brush surface, ∼90% of the adherent bacteria are released from the surface, presumably due to repulsive electrostatic interactions. This approach provides a simple method for the preparation of surfaces on which bacterial adhesion can be controlled and is applicable to a wide variety of substrates.


Asunto(s)
Acrilamidas/química , Adhesión Bacteriana , Ácidos Borónicos/química , Metacrilatos/química , Nylons/química , Espectroscopía de Fotoelectrones , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Propiedades de Superficie
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(9): 2372-6, 2014 Sep.
Artículo en Zh | MEDLINE | ID: mdl-25532328

RESUMEN

A new method of near-infrared (NIR) diffuse reflectance spectroscopy is proposed to rapidly determine the degree of polymerization (DP) of natural cellulose (cotton and wood) pulp produced by a new clean pulping process. One hundred and ninety five samples were collected and their DP data were determined by standard method GB/T 9107-1999. The spectroscopy measurement method of the samples was studied and their near-infrared diffuse reflectance spectra were collected. The quantitative DP calibration models of one mixed cotton & wood and two separate cotton and wood pulps were established by partial least squares (PLS). The optimum models were developed using the spectra pretreated by derivative, autoscaling and mean-centering, and their performance is as follows: correlation coefficient of 0.980, 0.993 and 0.886, and RMSEP of 147, 143 and 53, respectively. The accuracy of NIR method was also studied. The results show that the accuracy of the two separate models of cotton and wood is better than that of the mixed model, and the precision of the two separate models is better than that of GB/T9107-1999. The identification model of cotton and wood was also established using principal component analysis (PCA). The result shows that the spectra of cotton and wood pulp have obvious difference, and the model can identify successfully the two kinds of pulp. The result indicates that the new NIR method is feasible to realize the on-line analysis of polymerization degree of natural cellulose pulp with its advantage of rapidness and easy operation.


Asunto(s)
Celulosa/química , Espectroscopía Infrarroja Corta , Gossypium , Análisis de los Mínimos Cuadrados , Modelos Teóricos , Análisis de Componente Principal , Madera
6.
J Colloid Interface Sci ; 662: 914-927, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38382375

RESUMEN

Ultrasound and X-rays possess remarkable tissue penetration capabilities, making them promising candidates for cancer therapy. Sonodynamic therapy, which utilizes ultrasound excitation, offers a safer alternative to radiotherapy and can be combined with X-rays to mitigate the adverse effects on normal tissues. In this study, we developed a bismuth-based heterostructure semiconductor (BFIP) to enhance the efficacy of radiotherapy and sonodynamic therapy in treating breast cancer. The semiconductor is fabricated through a two-step process involving the synthesis of porous spherical bismuth fluoride and partially reduced to bismuth oxyiodide. Then, followed by surface modification with amphiphilic polyethylene glycol, BFIP is fabricated. Incorporating heavy atoms in the BFIP enhances radiosensitivity. The BFIP exhibits superior carrier separation efficiency compared to bismuth fluoride, generating a substantial quantity of reactive oxygen species upon ultrasound stimulation. Moreover, the BFIP effectively depletes glutathione through coordination and hole-mediated oxidation pathways, disrupting the tumor microenvironment and inducing oxidative stress. Encouraging results are acquired in both in vitro cell and in vivo tumor models. Our study provides a de-risking strategy by utilizing ultrasound as a partial substitute for X-rays in treating deep-seated tumors, offering a viable research direction for constructing a unified nanoplatform.


Asunto(s)
Bismuto , Neoplasias , Humanos , Fluoruros , Glutatión , Estrés Oxidativo , Polietilenglicoles , Línea Celular Tumoral , Especies Reactivas de Oxígeno , Microambiente Tumoral
7.
Luminescence ; 28(5): 673-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22961928

RESUMEN

A simple and new method for the simultaneous determination of procaine (Pro), lidocaine (Lid), ropivacaine (Rop) and bupivacaine (Bup) was developed using capillary electrophoresis separation with mixed micelles and electrochemiluminescence detection. The use of mixed micelles of 2.0 × 10(-3) mol/L sodium dodecyl sulfate (SDS) and 8.0 × 10(-3) mol/L Tween 20 greatly improved separation selectivity. The detection sensitivities of four drugs with a Pt working electrode were increased by modification of the Pt electrode with europium(III)-doped Prussian Blue analog (Eu-PB). Under optimal conditions, the four local anesthetics were well separated and detected. The limits of detection (LOD, S/N = 3) of Pro, Lid, Rop and Bup in standard solution are 2.5 × 10(-8) , 1.3 × 10(-8) , 3.0 × 10(-8) and 4.1 × 10(-8) mol/L, respectively. The limits of quantitation (LOQ, S/N = 10) of Pro, Lid, Rop and Bup are 2.3 × 10(-7) , 1.2 × 10(-7) , 3.7 × 10(-7) and 5.6 × 10(-7) mol/L in a human urine sample, and 8.5 × 10(-7) , 6.9 × 10(-7) , 2.8 × 10(-6) and 1.1 × 10(-6) mol/L in a human serum sample, respectively. The recoveries of four drugs at different spiked concentrations in human urine and serum samples were between 86.5 and 107.6%. The proposed method has been successfully applied to determine local anesthetics in biofluids.


Asunto(s)
Anestésicos Locales/análisis , Técnicas Electroquímicas , Luminiscencia , Polisorbatos/química , Dodecil Sulfato de Sodio/química , Amidas/análisis , Bupivacaína/análisis , Electroforesis Capilar , Femenino , Voluntarios Sanos , Humanos , Lidocaína/análisis , Micelas , Procaína/análisis , Ropivacaína
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(1): 60-4, 2013 Jan.
Artículo en Zh | MEDLINE | ID: mdl-23586225

RESUMEN

A new near infrared diffuse reflectance spectroscopy method is proposed to rapidly detect alpha-cellulose content of natural cellulose (plant fiber: cotton, wood) pulp in a new clean pulping process. One hundred forty two samples were collected and their alpha-cellulose content data were determined by standard method GB/T 9107-1999. The samples were homogenized by grinding pretreatment to improve spectroscopy measurement accuracy. Effective classification models were built by SIMCA, with the total correct identification. Using partial least squares (PLS) quantitative calibration, alpha-cellulose of the whole and separate cotton and wood pulp was established, with the correlation coefficients of 0.954, 0.911, 0.839, SEP, 0.024, 0.012 and 0.016, respectively. The repeatability results obtained by the new method are in agreement with the results from GB/T 9107-1999. The new method is feasible for determining alpha-cellulose content of natural cellulose (plant fiber: cotton, wood) in clean pulping process.


Asunto(s)
Celulosa/análisis , Celulosa/química , Espectroscopía Infrarroja Corta/métodos , Calibración , Celulosa/metabolismo , Gossypium/química , Análisis de los Mínimos Cuadrados , Madera/química
9.
Nanoscale ; 15(2): 809-819, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36533522

RESUMEN

Signal enhancement of magnetic resonance imaging (MRI) in the diseased region is dependent on the molecular structure of the MRI contrast agent. In this study, a macromolecular contrast agent, Branched-LAMA-DOTA-Cy5.5-Gd (BLDCGd), was prepared to target liver cancer. Due to the affinity of lactose to the Asialoglycoprotein receptor (ASGPR) over-expressed on the surface of liver cancer cells, lactose was selected as the targeting moiety in the contrast agent. A cathepsin B-sensitive tetrapeptide, GFLG, was used as a linkage moiety to construct a cross-linked macromolecular structure of the contrast agent, and the contrast agent could be degraded into fragments for clearance. A small-molecular-weight molecule, DOTA-Gd, and a fluorescent dye, Cy5.5, were conjugated to the macromolecular structure via a thiol-ene click reaction. The contrast agent, BLDCGd, had a high molecular weight (81 kDa) and a small particle size (59 ± 12 nm). Its longitudinal relaxivity (12.62 mM-1 s-1) was 4-fold that of the clinical agent DTPA-Gd (3.42 mM-1 s-1). Signal enhancement of up to 184% was observed at the tumor site in an H22 cell-based mouse model. A high accumulation level of BLDCGd in the liver tumor observed from MRI was confirmed from the fluorescence images obtained from the same contrast agent. BLDCGd showed no toxicity to HUVECs and H22 cells in vitro, and low blood chemistry indexes and no distinct histopathological abnormalities were also observed in vivo after injection of BLDCGd since it could be metabolized through the kidneys according to the in vivo MRI results of major organs. Therefore, the branched macromolecule BLDCGd could have great potential as an efficacious and bio-safe nanoscale MRI contrast agent for clinical diagnosis of liver cancer.


Asunto(s)
Neoplasias Hepáticas , Polímeros , Ratones , Animales , Medios de Contraste/farmacología , Medios de Contraste/química , Lactosa/farmacología , Sustancias Macromoleculares , Neoplasias Hepáticas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos
10.
EBioMedicine ; 97: 104828, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37837933

RESUMEN

BACKGROUND: Microplastics (MPs) have garnered widespread attention because of their presence in human placenta, stool, and even blood. Ingestion is considered the major route of human exposure to MPs. It has been found that the consumption of food and water is associated with more MP abundance in human stools. The usage of plastic containers, particularly feeding bottles, may be a major contributor to MP contamination. However, human exposure to MPs and potential factors that influence exposure, especially for preschoolers, remains largely unknown. When exposed to MPs, mice exhibited gut microbiota dysbiosis, including alterations in diversity indices, a decreased relative abundance of probiotics and an increased abundance of pathogenic bacteria. Such results have also been observed in human gut in vitro models, however, the actual association between MP exposure and human intestinal microbiota remains unclear. Therefore, this study aimed to evaluate MP concentrations in preschoolers' stools, explore possible dietary factors that influence preschooler exposure to MPs, and investigate their potential association with the gut microbiota. METHODS: A cross-sectional study was conducted in Xiamen, China in October 2022. We investigated the feeding behaviours and dietary habits of preschool children. A total of 69 couples of stool samples were collected and analyzed for MPs test and gut microbiota analysis. Pyrolysis-gas chromatography coupled with mass spectrometry (Py-GC/MS) was used for quantifying 11 types of MPs. The gut microbiota composition was analyzed by 16S rRNA gene sequencing. FINDINGS: The results showed that only polyvinyl chloride (PVC), polyethylene terephthalate (PET), polyethylene (PE), and polyamide 6 (PA6) were detected in 85.5% stool samples, with concentrations of 317.4 (152.0, 491.9) µg/g dw, 299.0 (196.1, 619.9) µg/g dw, 206.2 (154.1, 240.3) µg/g dw, and 17.9 (13.4, 18.6) µg/g dw, respectively. The median estimated daily intake (EDI) for preschoolers was 425.9 (272.5, 762.3) µg/kg-bw/d. Dairy intake may influence MP concentration in preschoolers' stools, and the usage of feeding bottles may be a specific source of MP contamination. Moreover, higher PVC concentrations were observed in the stools when the children took more time to eat a meal. MP exposure was inversely associated with alpha indices and possibly affected certain probiotic taxa, such as Parabacteroides and Alistipes, in preschool children. INTERPRETATION: Our data provided baseline evidence for MP exposure doses and potential dietary factors that may influence MP exposure in preschoolers. These findings supported the perspective that MP exposure might be associated with the disturbance of gut microbiota. Further studies focusing on sensitive populations with larger sample sizes are needed. FUNDING: This study was funded by the National Natural Science Foundation of China (grant number: 82003412), the Shanghai Municipal Health Commission (grant number: 20214Y0019), and the Project of Shanghai Municipal Financial Professional foundation (Food Safety Risk Assessment) (grant number: RA-2022-06).


Asunto(s)
Microbioma Gastrointestinal , Contaminantes Químicos del Agua , Humanos , Preescolar , Animales , Ratones , Microplásticos , Plásticos , Proyectos Piloto , ARN Ribosómico 16S/genética , Estudios Transversales , China , Polietileno/análisis , Contaminantes Químicos del Agua/análisis
11.
J Mater Chem B ; 10(32): 6158-6170, 2022 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-35904091

RESUMEN

Tissue-engineered vascular grafts (TEVGs) provide a new alternative for vascular construction. Nitric oxide (NO) is capable of promoting vascular tissue regeneration and reducing restenosis caused by vascular implantation. Therefore, in situ production of NO by catalytic decomposition of the endogenous donor is a promising strategy to fabricate a TEVG. In this study, poly(ε-caprolactone) (PCL) was first electrospun with keratin (Ker) to afford PCL/Ker mats and then incorporated with Cu(II) ions through multiple interactions. This strategy is very simple, green, and facile. Particularly, the incorporated Cu(II) ions were partially reduced to Cu(I) ions due to the reducibility of keratin. The chelated copper ions were expected to catalyze the generation of NO from endogenous S-nitrosothiol (RSNO). As a result, PCL/Ker-Cu mats selectively accelerated the adhesion, migration, and growth of human umbilical vein endothelial cells (HUVECs), while inhibiting the proliferation of human umbilical artery smooth muscle cells (HUASMCs). Furthermore, these mats exhibited excellent blood compatibility and significant antibacterial activity. Vascular implantation in vivo indicated that the tubular mats could inhibit thrombus formation and retain patency for 3 months after implantation in the rabbit carotid artery. More importantly, vascular remodeling was observed during follow-up, including a complete endothelium and smooth muscle layer. Taken together, the PCL/Ker-Cu mats have great potential application in vascular tissue regeneration.


Asunto(s)
Prótesis Vascular , Queratinas , Animales , Proliferación Celular , Cobre/farmacología , Proteínas del Citoesqueleto , Células Endoteliales de la Vena Umbilical Humana , Humanos , Óxido Nítrico/farmacología , Poliésteres , Conejos , Ingeniería de Tejidos
12.
Virol J ; 8: 418, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21880157

RESUMEN

BACKGROUND: In this study, we developed a rapid, one step colloid gold strip (CGS) capable of specifically detecting type Asia1 foot-and-mouth disease virus (FMDV). We have produced two monoclonal antibodies (mAb) to type Asia1 FMD (named 1B8 and 5E2). On the test strip, the purified 1B8 labelled with the colloidal gold was used as the detector, and the purified 5E2 and goat anti-mouse antibodies were wrapped onto nitrocellulose (NC) membranes as the test and the control line, respectively. The rapid colloidal gold stereotype diagnostic strip was housed in a plastic case. RESULTS: In specificity and sensitivity assay, there was no cross-reaction of the antigen with the other type of FMD and SVDV. The detection sensitivity was found to be as high as 10(-5) dilution of Asia1/JSL/05 (1 × 10(7.2)TCID(50)/50 µL). There was excellent agreement between the results obtained by CGS and reverse indirect hemagglutination assay (RIHA), and the agreement can reach to 98.75%. CONCLUSION: We developed colloidal gold strips that have good qualities and does not require specialized equipment or technicians. This method provided a feasible, convenient, rapid, and effective for detecting type Asia1 FMDV in the fields.


Asunto(s)
Anticuerpos Antivirales/inmunología , Antígenos Virales/análisis , Enfermedades de los Bovinos/diagnóstico , Dermatoglifia del ADN/métodos , Virus de la Fiebre Aftosa/genética , Fiebre Aftosa/diagnóstico , Inmunoensayo , Tiras Reactivas , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/metabolismo , Anticuerpos Antivirales/metabolismo , Antígenos Virales/inmunología , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/virología , Colodión/química , Colodión/metabolismo , Femenino , Fiebre Aftosa/inmunología , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/clasificación , Virus de la Fiebre Aftosa/inmunología , Oro Coloide/química , Oro Coloide/inmunología , Oro Coloide/metabolismo , Pruebas de Hemaglutinación , Ratones , Ratones Endogámicos BALB C , Sensibilidad y Especificidad
13.
Food Chem ; 348: 129126, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-33515947

RESUMEN

In this study, surface imprinting, magnetic separation, and fluorescent detection were integrated to develop a dual-recognition sensor (MF-MIPs), which was used for highly selective and sensitive detection of 4-nitrophenol (4-NP) in food samples. Silane-functionalized carbon dots (Si-CDs) participated in the imprinting process and were uniformly distributed into the MIPs layers. MF-MIPs sensor exhibited a high fluorescence response and selectivity based on the dual-recognition mechanism of imprinting recognition and fluorescence identification. The relative fluorescence intensity of MF-MIPs sensor presented a good linear relationship in the range of 0.08-10 µmol·L-1 with a low limit of detection (23.45 nmol·L1) for 4NP. MF-MIPs sensor showed high anti-interference, as well as excellent stability and reusability. The 4-NP recovery from spiked food samples ranged from 93.20 to 102.15%, and the relative standard deviation was lower than 5.0%. Therefore, MF-MIPs sensor may be a promising method for 4-NP detection in food samples.


Asunto(s)
Análisis de los Alimentos/métodos , Magnetismo , Impresión Molecular , Nitrofenoles/análisis , Carbono/química , Límite de Detección , Polímeros/química , Puntos Cuánticos/química , Reproducibilidad de los Resultados , Silanos/química , Espectrometría de Fluorescencia
14.
Exp Neurol ; 326: 113176, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31926167

RESUMEN

Epidemiological studies suggest that chronic periodontitis (CP) is closely associated with the incidence and progression of cognitive impairment. The present study investigated the causal relationship between CP and cognitive decline and the underlying mechanism in mice. Long-term ligature around the left second maxillary molar tooth was used to induce CP in mice. Severe alveolar bone loss and inflammatory changes were observed in gingival tissues, accompanied by progressive cognitive deficits during a 12-month period. We also observed cerebral neuronal and synaptic injury and glial activation in this mouse model of CP. Furthermore, CP mice exhibited significant dysbiosis of the oral and gut microbiota, disruption of the intestinal barrier and blood-brain barrier, increases in the serum contents of proinflammatory cytokines and lipopolysaccharide (LPS), and increases in brain LPS levels, Toll-like receptor 4 (TLR4) expression, nuclear factor-κB (NF-κB) nuclear translocation and proinflammatory cytokine mRNA levels. These results indicate that CP may directly induce progressive cognitive decline and its mechanism is probably related to microbiota-gut-brain axis disorders, LPS/TLR4/NF-κB signaling activation and neuroinflammatory responses in mice. Therefore, the microbiota-gut-brain axis may provide the potential strategy for the prevention and treatment of CP-associated cognitive impairment.


Asunto(s)
Encefalopatías/etiología , Periodontitis Crónica/complicaciones , Trastornos del Conocimiento/etiología , Microbioma Gastrointestinal , Proceso Alveolar/patología , Animales , Barrera Hematoencefálica , Encefalopatías/psicología , Enfermedad Crónica , Periodontitis Crónica/psicología , Trastornos del Conocimiento/psicología , Citocinas/sangre , Lipopolisacáridos/sangre , Masculino , Ratones , FN-kappa B , Neuroglía/patología , Neuronas/patología , Transducción de Señal , Sinapsis/patología , Receptor Toll-Like 4
15.
ACS Appl Mater Interfaces ; 12(52): 57768-57781, 2020 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-33326213

RESUMEN

Solid tumors inevitably develop radioresistance due to low oxygen partial pressure in the tumor microenvironment. Despite numerous attempts, there are still few effective ways to avoid the hypoxia-induced poor radiotherapeutic effect. To overcome this problem, platinum (Pt) nanodots were fabricated into a mesoporous bismuth (Bi)-based nanomaterial to construct a biodegradable nanocomposite BiPt-folic acid-modified amphiphilic polyethylene glycol (PFA). BiPt-PFA could act as a radiosensitizer to enhance the absorption of X-rays at the tumor site and simultaneously trigger response behaviors related to the tumor microenvironment due to the enrichment of materials in the tumor area. During this process, the Bi-based component consumed glutathione via coordination, thus altering the oxidative stress balance, while Pt nanoparticles catalyzed the decomposition of hydrogen peroxide to generate oxygen, thereby relieving tumor hypoxia. Both Pt and Bi thus co-modulated the tumor microenvironment to improve the radiotherapeutic effect. In addition, Pt dots in BiPt-PFA had strong near-infrared absorption ability and created an intensive photothermal therapeutic effect. Modulation of the tumor microenvironment could thus improve the therapeutic effect in hypoxic tumors by a combination of photothermal therapy and enhanced radiotherapy. BiPt-PFA, as a biodegradable nanocomposite, may thus modulate the tumor microenvironment to enhance the hypoxic tumor therapeutic effect by thermoradiotherapy.


Asunto(s)
Bismuto/química , Nanocompuestos/química , Fármacos Sensibilizantes a Radiaciones/química , Hipoxia Tumoral/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacos , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Humanos , Hipertermia Inducida , Nanopartículas del Metal/química , Ratones , Platino (Metal)/química , Polietilenglicoles/química , Porosidad , Fármacos Sensibilizantes a Radiaciones/farmacología , Seguridad , Solubilidad , Hipoxia Tumoral/efectos de la radiación , Microambiente Tumoral/efectos de la radiación , Agua/química
16.
Int J Nanomedicine ; 14: 4261-4276, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31289441

RESUMEN

Purpose: In the field of small-caliber vascular scaffold research, excellent vascular remodeling is the key to ensuring anticoagulant function. We prepared an off-the-shelf bi-layered vascular scaffold with a dense inner layer and a loose outer layer and evaluated its remodeling capabilities by in vivo transplantation. Materials and Methods: Based on poly(L-lactide-co-ε-caprolactone) (PLCL), silk fibroin(SF), and heparin (Hep), PLCL/SF/Hep bi-layered scaffolds and PLCL/Hep bi-layered scaffolds were prepared by electrospinning. The inner layer was a PLCL/SF/Hep or PLCL/Hep nanofiber membrane, and the outer layer was PLCL/SF nano yarn. The in vitro tests included a hydrophilicity test, mechanical properties test, and blood and cell compatibility evaluation. The in vivo evaluation was conducted via single rabbit carotid artery replacement and subsequent examinations, including ultrasound imaging, immunoglobulin assays, and tissue section staining. Results: Compared to the PLCL/Hep nanofiber membrane, the hydrophilicity of the PLCL/SF/Hep nanofiber membrane was significantly improved. The mechanical strength met application requirements. Both the blood and cell compatibility were optimal. Most importantly, the PLCL/SF/Hep scaffolds maintained lumen patency for 3 months after carotid artery transplantation in live rabbits. At the same time, CD31 and α-SMA immunofluorescence staining confirmed bionic endothelial and smooth muscle layers remodeling. Conclusion: Using this hybrid strategy, PLCL and SF were combined to manufacture bi-layered small-caliber vascular scaffolds; these PLCL/SF/Hep scaffolds showed satisfactory vascular remodeling.


Asunto(s)
Fibroínas/química , Heparina/farmacocinética , Poliésteres/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Arterias Carótidas , Proliferación Celular , Liberación de Fármacos , Heparina/química , Células Endoteliales de la Vena Umbilical Humana , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Ensayo de Materiales , Nanofibras/química , Adhesividad Plaquetaria , Prótesis e Implantes , Conejos
17.
Biomech Model Mechanobiol ; 17(1): 223-234, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28879626

RESUMEN

Cellular adhesion plays a critical role in biological systems and biomedical applications. Cell deformation and biophysical properties of adhesion molecules are of significance for the adhesion behavior. In the present work, dynamic adhesion of a deformable capsule to a planar substrate, in a linear shear flow, is numerically simulated to investigate the combined influence of membrane deformability (quantified by the capillary number) and bond formation/dissociation rates on the adhesion behavior. The computational model is based on the immersed boundary-lattice Boltzmann method for the capsule-fluid interaction and a probabilistic adhesion model for the capsule-substrate interaction. Three distinct adhesion states, detachment, rolling adhesion and firm adhesion, are identified and presented in a state diagram as a function of capillary number and bond dissociation rate. The impact of bond formation rate on the state diagram is further investigated. Results show that the critical bond dissociation rate for the transition of rolling or firm adhesion to detachment is strongly related to the capsule deformability. At the rolling-adhesion state, smaller off rates are needed for larger capillary number to increase the rolling velocity and detach the capsule. In contrast, the critical off rate for firm-to-detach transition slightly increases with the capillary number. With smaller on rate, the effect of capsule deformability on the critical off rates is more pronounced and capsules with moderate deformability are prone to detach by the shear flow. Further increasing of on rate leads to large expansion of both rolling-adhesion and firm-adhesion regions. Even capsules with relatively large deformability can maintain stable rolling adhesion at certain off rate.


Asunto(s)
Membranas Artificiales , Reología , Adhesividad , Simulación por Computador , Ligandos , Modelos Biológicos , Factores de Tiempo
18.
Injury ; 49(8): 1477-1484, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29921534

RESUMEN

Longitudinally oriented microstructures are essential for a nerve scaffold to promote the significant regeneration of injured peripheral axons across nerve gaps. In the current study, we present a novel nerve-guiding collagen-chitosan (CCH) scaffold that facilitated the repair of 30 mm-long sciatic nerve defects in beagles. The CCH scaffolds were observed with a scanning electron microscope. Eighteen beagles were equally divided into CCH group, autograft group and non-graft group. The posture and gait of each dog was recorded at 12 and 24 weeks after surgery. Electrophysiological tests, Fluoro-Gold retrograde tracing test, Histological assessment of gastrocnemius and immunofluorescent staining of nerve regeneration were performed. Our investigation of regenerated sciatic nerves indicated that a CCH scaffold strongly supported directed axon regeneration in a manner similar to that achieved by autologous nerve transplantation. In vivo animal experiments showed that the CCH scaffold achieved nerve regeneration and functional recovery equivalent to that achieved by an autograft but without requiring the exogenous delivery of regenerative agents or cell transplantation. We conclude that CCH nerve guides show great promise as a method for repairing peripheral nerve defects.


Asunto(s)
Regeneración Nerviosa/fisiología , Nervio Ciático/fisiopatología , Neuropatía Ciática/patología , Animales , Materiales Biocompatibles/química , Quitosano/química , Perros , Masculino , Modelos Animales , Prótesis e Implantes , Recuperación de la Función , Neuropatía Ciática/cirugía , Ingeniería de Tejidos
19.
Pathol Res Pract ; 213(4): 394-399, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28283209

RESUMEN

AIM: The use of saliva as a diagnostic fluid enables non-invasive sampling and thus is a prospective sample for disease tests. This study fully utilized the information from the salivary transcriptome to characterize pancreatic cancer related genes and predict novel salivary biomarkers. METHODS: We calculated the enrichment scores of gene ontology (GO) and pathways annotated in Kyoto Encyclopedia of Genes and Genomes database (KEGG) for pancreatic cancer-related genes. Annotation of GO and KEGG pathway characterize the molecular features of genes. We employed Random Forest classification and incremental feature selection to identify the optimal features among them and predicted novel pancreatic cancer-related genes. RESULTS: A total of 2175 gene ontology and 79 KEGG pathway terms were identified as the optimal features to identify pancreatic cancer-related genes. A total of 516 novel genes were predicted using these features. We discovered 29 novel biomarkers based on the expression of these 516 genes in saliva. Using our new biomarkers, we achieved a higher accuracy (92%) for the detection of pancreatic cancer. Another independent expression dataset confirmed that these novel biomarkers performed better than the previously described markers alone. CONCLUSION: By analyzing the information of the salivary transcriptome, we predict pancreatic cancer-related genes and novel salivary gene markers for detection.


Asunto(s)
Biomarcadores de Tumor/genética , Perfilación de la Expresión Génica/métodos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Saliva/química , Ontología de Genes , Humanos , Reacción en Cadena de la Polimerasa
20.
ACS Appl Mater Interfaces ; 8(23): 14442-52, 2016 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-27224957

RESUMEN

Surface coimmobilization modifications of blood-contacting devices with both antithrombogenic moieties and endothelium-inducing biomolecules may create a synergistic effect to improve their performance. However, it is difficult to perform covalent dual-functionalization with both biomolecules on the surface of normally used synthetic polymeric substrates. Herein, we developed and characterized an orthogonally functionalizable polymer, biodegradable elastic poly(ester urethane)urea with disulfide and amino groups (PUSN), which was further fabricated into electropun fibrous scaffolds and surface modified with heparin and endothelial progenitor cells (EPC) recruiting peptide (TPS). The modification effects were assessed through platelet adhesion, EPC, and HUVEC proliferation. Results showed the dual modified PUSN scaffolds demonstrated a synergistic effect of reduced platelet deposition and improved EPC proliferation in vitro study, and demonstrated their potential application in small diameter vascular regeneration.


Asunto(s)
Prótesis Vascular , Materiales Biocompatibles Revestidos/química , Péptidos/metabolismo , Poliuretanos/química , Adhesión Celular , Endotelio/citología , Heparina/metabolismo , Humanos , Péptidos/química , Adhesividad Plaquetaria , Andamios del Tejido/química
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