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1.
Int J Cancer ; 151(9): 1462-1473, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-35689438

RESUMEN

We aimed to explore the association of combined risk factors with risk of death from upper gastrointestinal (UGI) cancer, including esophageal squamous cell carcinoma (ESCC), gastric cardia carcinoma (GCC) and gastric noncardia carcinoma (GNCC) in the Linxian Nutrition Intervention Trial (NIT) cohort. The NIT cohort included 29 584 healthy adults. A combined risk score (CRS) was calculated using a point system method based on 10 risk factors collected at baseline, including gender, smoking, alcohol drinking, body mass index, family history of UGI cancer, drinking tap water, tooth loss and consumption of fresh fruit, eggs and meat. Possible score ranged from 0 to 31, and higher score indicated as poorer health status. Subjects were divided into three groups by the CRS (<12 points, 12 to 20 points and >20 points). The group of CRS <12 points was considered as the reference. During the 30-year follow-up, we identified 4553 UGI cancer deaths. Compared to subjects with a CRS <12 points, the adjusted HRs for CRS of 12 to 20 points and >20 points were 1.69 (95% CI: 1.56-1.83) and 3.06 (95% CI: 2.82-3.33) for UGI cancer mortality, respectively (Ptrend < .001). Comparable associations were also observed for ESCC, GCC and GNCC mortality. Results remained similar across different age groups (Pinteraction > .05). All HRs observed in the second half follow-up period were stronger than that observed in the first half follow-up period. Our study indicated that higher CRS was associated with increased risk of UGI cancer mortality. Appropriate measures should be taken to reduce unhealthy lifestyles.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Neoplasias Gastrointestinales , Neoplasias Gástricas , Adulto , China/epidemiología , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/epidemiología , Neoplasias Gastrointestinales/epidemiología , Humanos , Estudios Prospectivos , Factores de Riesgo , Neoplasias Gástricas/patología
2.
Semin Immunol ; 29: 14-23, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28583764

RESUMEN

Urinary bladder matrix (UBM) is used clinically for management of wounds and reinforcement of surgical soft tissue repair, among other applications. UBM consists of the lamina propria and basal lamina of the porcine urinary bladder, and is decellularized as part of the process to manufacture the medical device. UBM is composed mainly of Collagen I, but also contains a wide variety of fibrillar and basement membrane collagens, glycoproteins, proteoglycans and ECM-associated factors. Upon application of the biomaterial in a traumatic or non-traumatic setting in a mouse model, there is a cascade of immune cells that respond to the damaged tissue and biomaterial. Here, through the use of multicolor flow cytometry, we describe the various cells that infiltrate the UBM scaffold in a subcutaneous and volumetric muscle injury model. A wide variety of immune cells are found in the UBM scaffold immune microenvironment (SIM) including F4/80+ macrophages, CD11c+ dendritic cells, CD3+ T cells and CD19+ B cells. A systemic IL-4 upregulation and a local M2-macrophage response were observed in the proximity of the implanted UBM. The recruitment and activation of these cells is dependent upon signals from the scaffold and communication between the different cell types present.


Asunto(s)
Materiales Biocompatibles/metabolismo , Matriz Extracelular/metabolismo , Proteoma/metabolismo , Andamios del Tejido , Vejiga Urinaria/metabolismo , Animales , Microambiente Celular , Matriz Extracelular/inmunología , Humanos , Ratones , Modelos Animales , Medicina Regenerativa , Ingeniería de Tejidos
3.
Anal Bioanal Chem ; 412(25): 6927-6938, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32712814

RESUMEN

Real-time fluorescence detection of nucleic acid exhibit excellent performance in analytical and diagnostic applications. However, the requirement of laboratory-based instrument and complex nucleic acid extraction greatly limits their application in point-of-care testing (POCT). Herein, a novel integrated silica membrane-based platform incorporating nucleic acid purification, amplification, and detection steps was developed. A universal and portable visualization platform was fabricated by incorporating denaturation bubble-mediated strand exchange amplification (SEA) reaction with silica membrane. The fluorescence signal of SYBR Green I with amplification products was visualized by the naked eye using a simple ultraviolet light on the silica membrane, and significant discrimination between the positive and negative samples could be easily and visually obtained. Besides, chitooligosaccharide-modified silica membrane allows the purification of nucleic acid in a totally aqueous system and enables in situ SEA. With the proposed integrated platform, 102-108 cfu/mL Vibrio parahaemolyticus could be successfully detected and excellent performance was also revealed for gram-positive pathogens. The detection limit of the method for artificially spiked oysters was 103 cfu/g and reached 100 cfu/g after 12 h enrichment. This proof-of-concept method could also be applied to a variety of nucleic acid amplification methods. We believe that the proposed silica membrane-based platform has great potential for the rapid and low-cost detection of nucleic acids especially in low-resource settings. Graphical abstract.


Asunto(s)
Microbiología de Alimentos , Membranas Artificiales , Técnicas Microbiológicas/economía , Ácidos Nucleicos/aislamiento & purificación , Dióxido de Silicio/química , Animales , Costos y Análisis de Costo , Límite de Detección , Ostreidae/microbiología , Pruebas en el Punto de Atención , Prueba de Estudio Conceptual
4.
Food Chem ; 405(Pt A): 134811, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36370568

RESUMEN

In this study, a paper-based enzyme biosensor for hypoxanthine (Hx) was developed, enabling visual and one-step fish freshness detection. Xanthine oxidase and horseradish peroxidase were immobilized on nitrocellulose membranes with 3,3',5,5'-tetramethylbenzidine to output the colour signal. Chitosan oligosaccharide lactate-modified nitrocellulose membranes entrapped the dual-enzyme system and exhibited excellent microfluidic aggregation effect. The developed enzyme biosensor produced a linear response of 0.01-0.16 mmolL-1 with a detection limit of 8.22 µmolL-1, and was selective for Hx with recoveries of 96.13-103.11 % for fish samples. These biosensors were attached directly to the surface of fish samples and the colour was revealed within 3 min. Colour signals can be judged by the naked-eye to distinguish between fresh and spoiled fish samples and analyzed by a smartphone for quantitative analysis. The biosensor shows great potential as a powerful pattern- and reagent-free device for on-site freshness evaluation of fish.


Asunto(s)
Técnicas Biosensibles , Microfluídica , Animales , Hipoxantina/análisis , Colodión , Xantina Oxidasa , Enzimas Inmovilizadas , Peces
5.
J Hazard Mater ; 456: 131685, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37257263

RESUMEN

The currently established tools and materials for elimination of the emerging contaminants from environmental and food matrices, particularly micro- and nano-scale plastics, have been largely limited by complicated preparation/operation, high cost, and poor degradability. Here we show that, crosslinking naturally occurring corn starch and gelatin produces ultralight porous sponge upon freeze-drying that can be readily enzymatically decomposed to glucose; The sponge affords capture of micro- and nano-scale plastics into its pores by simple pressing in an efficiency up to 90% while preserving excellent mechanical strength. Heterogeneous diffusion was found to play a dominant role in the adsorption of microplastics by the starch-gelatin sponge. Investigations into the performance of the sponge in complex matrices including tap water, sea water, soil surfactant, and take-out dish soup, further reveal a considerably high removal efficiency (60%∼70%) for the microplastics in the real samples. It is also suggested tiny plastics in different sizes be removable using the sponge with controlled pore size. With combined merits of sustainability, cost-effectiveness, and simple operation without the need for professional background for this approach, industrial and even household removal of tiny plastic contaminants from environmental and food samples are within reach.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Plásticos , Gelatina , Contaminantes Químicos del Agua/análisis , Agua
6.
J Nanosci Nanotechnol ; 9(2): 1361-4, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19441525

RESUMEN

Dental Enamel is the hardest mineralized tissue in the human body which is comprised of nanorod-like hydroxyapatite crystals arranged into a highly organized micro-architectural unit called an enamel prism. In this paper the direct growth of human enamel-like structures on human tooth using fluorapatite/phosphoric acid pastes is explored. SEM images show that the newly formed calcium phosphate crystals can be self-assembled into a similar ordered microstructure as those seen in human enamel. The mechanism of how these structures form is discussed. This work demonstrates the potential of applying nanotechnology to regenerate dental enamel clinically without cells.


Asunto(s)
Fosfatos de Calcio/química , Esmalte Dental/química , Humanos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión
7.
Mater Sci Eng C Mater Biol Appl ; 91: 688-695, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30033303

RESUMEN

In this study, a novel stereocomplexed micelle system was prepared from the self-assembly of enantiomeric PLA-based Y-shaped copolymers, i.e. folic acid-adamantane/ß-cyclodextrin-b-[poly(D-lactide)]2 (FA-AD/CD-b-(PDLA)2) and poly(2-dimethylaminoethyl methacrylate)-b-[poly(L-lactide)]2 (PDMAEMA-b-(PLLA)2) in aqueous solution. The newly designed Y-shaped copolymer FA-AD/CD-b-(PDLA)2 was prepared by a combination of "click" reaction and host guest interaction between FA-AD and CD-b-(PDLA)2. In addition, enantiomeric Y-shaped PDMAEMA-b-(PLLA)2 copolymer was synthesized through ring-opening polymerization (ROP) of L-lactide using three-head initiator with bromo and -OH at distal ends, followed by atom transfer radical polymerization (ATRP) of DMAEMA to obtain the desired macromolecular architecture. The resultant copolymers and their intermediates were characterized by 1H nuclear magnetic resonance (1H NMR) and gel permeation chromatography (GPC) techniques. Due to the strong stereocomplexation interaction, FA-AD/CD-b-(PDLA)2 and PDMAEMA-b-(PLLA)2 mixture could self-assemble into stable mixed micelles in aqueous solution. Further, the stereocomplexed micelles exhibited excellent biocompatibility as revealed in the cytotoxicity assay. Together with the intrinsic biodegradability of PLA, it is envisioned that the stereocomplexed micelles developed in this study can be used as a promising nanocarrier for targeting drug delivery.


Asunto(s)
Sistemas de Liberación de Medicamentos , Micelas , Polímeros/química , Rastreo Diferencial de Calorimetría , Supervivencia Celular , Ácido Fólico/química , Células HEK293 , Humanos , Ensayo de Materiales , Metacrilatos/síntesis química , Metacrilatos/química , Nylons/síntesis química , Nylons/química , Tamaño de la Partícula , Poliésteres/síntesis química , Poliésteres/química , Polímeros/síntesis química , Espectroscopía de Protones por Resonancia Magnética , Estereoisomerismo
8.
J Tissue Eng Regen Med ; 12(3): 821-829, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29049869

RESUMEN

Structural and biochemical cues of extracellular matrix can substantially influence the differentiation and maturation of cultured retinal pigment epithelial (RPE) cells. In this study, thin collagen vitrigels were engineered to create collagen nanofibrillar structures of different fibril densities in an effort to evaluate the maturation of human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells. The ultrastructure of the different collagen vitrigels was characterized by transmission electron microscopy, and the mechanical properties were evaluated by tensile testing. The pigmentation and polarization of cells, in addition to key RPE marker gene and protein expression levels, were analyzed to determine the differentiation of hESCs on the gels. The hESC-RPE differentiation was most significant in collagen vitrigels with low fibril density with mature collagen fibrils with diameter of around 60 nm and Young's modulus of 2.41 ± 0.13 MPa. This study provides insight into the influence of collagen nanofibrillar structures on hESC-RPE maturation and presents a potential bioengineered substratum for hESC-RPE for future preclinical and clinical applications.


Asunto(s)
Diferenciación Celular , Colágeno/farmacología , Células Epiteliales/citología , Geles/farmacología , Epitelio Pigmentado de la Retina/citología , Vitrificación , Animales , Bovinos , Polaridad Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Reactivos de Enlaces Cruzados/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/ultraestructura , Regulación de la Expresión Génica/efectos de los fármacos , Células Madre Embrionarias Humanas/citología , Células Madre Embrionarias Humanas/efectos de los fármacos , Células Madre Embrionarias Humanas/metabolismo , Células Madre Embrionarias Humanas/ultraestructura , Humanos , Pigmentación/efectos de los fármacos , Poliésteres/farmacología
9.
Biomaterials ; 33(12): 3375-87, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22322196

RESUMEN

Mesenchymal stem cell (MSC) is a promising cell source candidate in tissue engineering (TE) and regenerative medicine. However, the inability to target MSCs in tissues of interest with high efficiency and engraftment has become a significant barrier for MSC-based therapies. The mobilization and transfer of MSCs to defective/damaged sites in tissues or organs in vivo with high efficacy and efficiency has been a major concern. In the present study, we identified a peptide sequence (E7) with seven amino acids through phage display technology, which has a high specific affinity to bone marrow-derived MSCs. Subsequent analysis suggested that the peptide could efficiently interact specifically with MSCs without any species specificity. Thereafter, E7 was covalently conjugated onto polycaprolactone (PCL) electrospun meshes to construct an "MSC-homing device" for the recruitment of MSCs both in vitro and in vivo. The E7-conjugated PCL electrospun meshes were implanted into a cartilage defect site of rat knee joints, combined with a microfracture procedure to mobilize the endogenous MSCs. After 7 d of implantation, immunofluorescence staining showed that the cells grown into the E7-conjugated PCL electrospun meshes yielded a high positive rate for specific MSC surface markers (CD44, CD90, and CD105) compared with those in arginine-glycine-aspartic acid (RGD)-conjugated PCL electrospun meshes (63.67% vs. 3.03%; 59.37% vs. 2.98%; and 61.45% vs. 3.82%, respectively). Furthermore, the percentage of CD68 positive cells in the E7-conjugated PCL electrospun meshes was much lower than that in the RGD-conjugated PCL electrospun meshes (5.57% vs. 53.43%). This result indicates that E7-conjugated PCL electrospun meshes absorb much less inflammatory cells in vivo than RGD-conjugated PCL electrospun meshes. The results of the present study suggest that the identified E7 peptide sequence has a high specific affinity to MSCs. Covalently conjugating this peptide on the synthetic PCL mesh significantly enhanced the MSC recruitment of PCL in vivo. This method provides a wide range of potential applications in TE.


Asunto(s)
Artroplastia Subcondral , Células Madre Mesenquimatosas/citología , Péptidos/química , Poliésteres/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Anciano , Secuencia de Aminoácidos , Animales , Sitios de Unión , Cartílago/citología , Cartílago/cirugía , Adhesión Celular , Proliferación Celular , Humanos , Masculino , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/metabolismo , Persona de Mediana Edad , Biblioteca de Péptidos , Péptidos/metabolismo , Ratas
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