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1.
Int J Mol Sci ; 25(3)2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38339138

RESUMEN

Recent advances in biomedical research, particularly in optical applications, have sparked a transformative movement towards replacing synthetic polymers with more biocompatible and sustainable alternatives. Most often made from plastics or glass, these materials ignite immune responses from the body, and their production is based on environmentally harsh oil-based processes. Biopolymers, including both polysaccharides and proteins, have emerged as a potential candidate for optical biomaterials due to their inherent biocompatibility, biodegradability, and sustainability, derived from their existence in nature and being recognized by the immune system. Current extraction and fabrication methods for these biomaterials, including thermal drawing, extrusion and printing, mold casting, dry-jet wet spinning, hydrogel formations, and nanoparticles, aim to create optical materials in cost-effective and environmentally friendly manners for a wide range of applications. Present and future applications include optical waveguides and sensors, imaging and diagnostics, optical fibers, and waveguides, as well as ocular implants using biopolymers, which will revolutionize these fields, specifically their uses in the healthcare industry.


Asunto(s)
Materiales Biocompatibles , Polisacáridos , Biopolímeros , Polímeros
2.
BMC Surg ; 23(1): 197, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37430232

RESUMEN

BACKGROUND: Vertebroplasty is the main minimally invasive operation for osteoporotic vertebral compression fracture (OVCF), which has the advantages of rapid pain relief and shorter recovery time. However, new adjacent vertebral compression fracture (AVCF) occurs frequently after vertebroplasty. The purpose of this study was to investigate the risk factors of AVCF and establish a clinical prediction model. METHODS: We retrospectively collected the clinical data of patients who underwent vertebroplasty in our hospital from June 2018 to December 2019. The patients were divided into a non-refracture group (289 cases) and a refracture group (43 cases) according to the occurrence of AVCF. The independent predictive factors for postoperative new AVCF were determined by univariate analysis, least absolute shrinkage and selection operator (LASSO) logistic regression, and multivariable logistic regression analysis. A nomogram clinical prediction model was established based on relevant risk factors, and the receiver operating characteristic curve (ROC), calibration curve, and decision curve analysis (DCA) were used to evaluate the prediction effect and clinical value of the model. After internal validation, patients who underwent vertebroplasty in our hospital from January 2020 to December 2020, including a non-refracture group (156 cases) and a refracture group (21 cases), were included as the validation cohort to evaluate the prediction model again. RESULTS: Three independent risk factors of low bone mass density (BMD), leakage of bone cement and "O" shaped distribution of bone cement were screened out by LASSO regression and logistic regression analysis. The area under the curve (AUC) of the model in the training cohort and the validation cohort was 0.848 (95%CI: 0.786-0.909) and 0.867 (95%CI: 0.796-0.939), respectively, showing good predictive ability. The calibration curves showed the correlation between prediction and actual status. The DCA showed that the prediction model was clinically useful within the whole threshold range. CONCLUSION: Low BMD, leakage of bone cement and "O" shaped distribution of bone cement are independent risk factors for AVCF after vertebroplasty. The nomogram prediction model has good predictive ability and clinical benefit.


Asunto(s)
Fracturas por Compresión , Fracturas de la Columna Vertebral , Vertebroplastia , Humanos , Cementos para Huesos/efectos adversos , Fracturas por Compresión/etiología , Fracturas por Compresión/cirugía , Modelos Estadísticos , Nomogramas , Pronóstico , Estudios Retrospectivos , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/cirugía , Vertebroplastia/efectos adversos
3.
Int J Mol Sci ; 24(4)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36835387

RESUMEN

Biopolymers are an emerging class of novel materials with diverse applications and properties such as superior sustainability and tunability. Here, applications of biopolymers are described in the context of energy storage devices, namely lithium-based batteries, zinc-based batteries, and capacitors. Current demand for energy storage technologies calls for improved energy density, preserved performance overtime, and more sustainable end-of-life behavior. Lithium-based and zinc-based batteries often face anode corrosion from processes such as dendrite formation. Capacitors typically struggle with achieving functional energy density caused by an inability to efficiently charge and discharge. Both classes of energy storage need to be packaged with sustainable materials due to their potential leakages of toxic metals. In this review paper, recent progress in energy applications is described for biocompatible polymers such as silk, keratin, collagen, chitosan, cellulose, and agarose. Fabrication techniques are described for various components of the battery/capacitors including the electrode, electrolyte, and separators with biopolymers. Of these methods, incorporating the porosity found within various biopolymers is commonly used to maximize ion transport in the electrolyte and prevent dendrite formations in lithium-based, zinc-based batteries, and capacitors. Overall, integrating biopolymers in energy storage solutions poses a promising alternative that can theoretically match traditional energy sources while eliminating harmful consequences to the environment.


Asunto(s)
Celulosa , Litio , Biopolímeros , Seda , Zinc
4.
BMC Oral Health ; 23(1): 54, 2023 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-36717826

RESUMEN

OBJECTIVE: The purpose of this study was to analyze the factors influencing the utilization of oral health care among 5 years old children. METHODS: We conducted two observational cross-sectional studies. The studies were conducted in 2005 and 2015 and included 5-year-old children who underwent dental examination by trained dentists and the caregivers of the children were requested to answer the questionnaire. Multi-level stratified sampling method was used. Chi-square tests were used to analyze the utilization of dental care and other socio-economic variables. Logistic regression models were employed to explore the primary factors influencing the use of dental care among pre-school children. RESULTS: In 2005, a total of 399 and in 2015, 492 child-caregiver pairs were included. The majority of the caregivers in both surveys were females, comprising 68.2% and 74.8% of the caregivers in 2005 and 2015, respectively. 75.2% and 87.0% (p < 0.05) of the respondents had an education level of lesser than 9 years. The prevalence of caries was higher in 2015 (63.2%) (p < 0.05) than in 2005 (53.4%). In 2005 and 2015, the utilization of dental care services was 20.8% and 20.0%, respectively. A statistically significant association was observed between caries and dental care use in 5-year-olds over the past decade. After adjusting for confounders, dental service usage among children in urban areas was 1.62 times higher than that of rural areas in 2005 (95% CI 0.069-0.571), and the self-assessment of caregivers regarding their child's oral health significantly improved oral health use in 2015. CONCLUSION: The utilization of dental care services over the past decade is insufficient among pre-school children in northwest China. Hence, with the decreasing gap about economic and health service resources, policymakers should place greater emphasis on raising awareness among caregivers about the oral health status of their children.


Asunto(s)
Caries Dental , Salud Bucal , Niño , Preescolar , Femenino , Humanos , Masculino , China/epidemiología , Estudios Transversales , Atención Odontológica , Caries Dental/epidemiología , Prevalencia
5.
J Clin Periodontol ; 49(10): 1067-1078, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35713233

RESUMEN

AIM: Periodontitis (PD) is the sixth most prevalent disease around the world and is involved in the development and progression of multiple systemic diseases. Previous studies have reported that PD may aggravate liver injuries. The objective of this study was to investigate whether and how PD affects liver fibrosis. MATERIALS AND METHODS: Ligature-induced PD (LIP) was induced in male C57/B6J mice, and sub-gingival plaques (PL) from patients with PD were applied to mouse teeth. Liver fibrosis was induced by carbon tetrachloride (CCl4 ) injection. The mice were randomly divided into six groups: Oil, Oil+LIP, Oil+LIP+PL, CCl4 , CCl4 +LIP, and CCl4 +LIP+PL. Alveolar bone resorption was evaluated by methylene blue staining. Hepatic function was analysed by serum alanine aminotransferase and hepatic hydroxyproline. Picrosirius red and α-smooth muscle actin (SMA) staining were used to evaluate the fibrotic area. RNA sequencing and quantitative RT-PCR were used to measure gene expression. Western blotting was used to measure protein levels. Flow cytometry was used to analyse the accumulation of immune cells. Mouse microbiota were analysed using 16S rRNA gene sequencing. RESULTS: Mice in the CCl4 +LIP+PL group displayed higher serum alanine aminotransferase and hepatic hydroxyproline as well as more Picrosirius red-positive and α-SMA-positive areas in liver samples than those of the CCl4 group, suggesting that PD (LIP+PL) aggravated CCl4 -induced hepatic dysfunction and liver fibrosis. Consistently, the expression of fibro-genic genes and the protein levels of transforming growth factor ß were much higher in the CCl4 +LIP+PL group than in the CCl4 group. Flow cytometry revealed that PD increased the accumulation of immune cells, including Kupffer cells, B cells, and Th17 cells, in the liver of mice with CCl4 treatment. PD also increased the expression of inflammatory genes and activated pro-inflammatory nuclear factor-kappa B pathway in the livers of CCl4 -injected mice. Moreover, PD altered both oral and liver microbiota in CCl4 -injected mice. CONCLUSIONS: PD aggravates CCl4 -induced hepatic dysfunction and fibrosis in mice, likely through the increase of inflammation and alteration of microbiota in the liver.


Asunto(s)
Cirrosis Hepática , Microbiota , Periodontitis , Actinas , Alanina Transaminasa , Animales , Compuestos Azo , Tetracloruro de Carbono/efectos adversos , Hidroxiprolina/metabolismo , Cirrosis Hepática/inducido químicamente , Masculino , Azul de Metileno , Ratones , Periodontitis/complicaciones , ARN Ribosómico 16S , Factor de Crecimiento Transformador beta/metabolismo
6.
Int J Mol Sci ; 23(3)2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-35163339

RESUMEN

Hydrogels from biopolymers are readily synthesized, can possess various characteristics for different applications, and have been widely used in biomedicine to help with patient treatments and outcomes. Polysaccharides, polypeptides, and nucleic acids can be produced into hydrogels, each for unique purposes depending on their qualities. Examples of polypeptide hydrogels include collagen, gelatin, and elastin, and polysaccharide hydrogels include alginate, cellulose, and glycosaminoglycan. Many different theories have been formulated to research hydrogels, which include Flory-Rehner theory, Rubber Elasticity Theory, and the calculation of porosity and pore size. All these theories take into consideration enthalpy, entropy, and other thermodynamic variables so that the structure and pore sizes of hydrogels can be formulated. Hydrogels can be fabricated in a straightforward process using a homogeneous mixture of different chemicals, depending on the intended purpose of the gel. Different types of hydrogels exist which include pH-sensitive gels, thermogels, electro-sensitive gels, and light-sensitive gels and each has its unique biomedical applications including structural capabilities, regenerative repair, or drug delivery. Major biopolymer-based hydrogels used for cell delivery include encapsulated skeletal muscle cells, osteochondral muscle cells, and stem cells being delivered to desired locations for tissue regeneration. Some examples of hydrogels used for drug and biomolecule delivery include insulin encapsulated hydrogels and hydrogels that encompass cancer drugs for desired controlled release. This review summarizes these newly developed biopolymer-based hydrogel materials that have been mainly made since 2015 and have shown to work and present more avenues for advanced medical applications.


Asunto(s)
Hidrogeles , Ingeniería de Tejidos , Alginatos/química , Materiales Biocompatibles/química , Biopolímeros/química , Gelatina , Humanos , Hidrogeles/química , Polisacáridos/química
7.
Int J Mol Sci ; 22(17)2021 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-34502496

RESUMEN

Micro-/nanofibers have shown high promise as drug delivery vehicles due to their high porosity and surface-area-to-volume ratio. The current study utilizes air-spraying, a novel fiber fabrication technique, to create silk micro-/nanofibers without the need for a high voltage power source. Air-spraying was used to create silk fibrous mats embedded with several model drugs with high efficiency. In order to compare the effect of biomaterial geometry on the release of the model drugs, silk films were also created and characterized. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and a drug release study were performed on both fiber and film samples to study how the model drugs interact with the protein structure. FTIR analysis showed that while drugs could interact with the protein structure of porous silk fibers, they could not interact with the flat geometry of silk films. As a result, fibers could protect select model drugs from thermal degradation and slow their release from the fiber network with more control than the silk films. A trend was also revealed where hydrophobic drugs were better protected and had a slower release than hydrophilic drugs. The results suggest that the physical and chemical properties of drugs and protein-based biomaterials are important for creating drug delivery vehicles with tailored release profiles and that fibers provide better tunability than films do.


Asunto(s)
Sistemas de Liberación de Medicamentos , Fibroínas/química , Membranas Artificiales , Nanofibras/química
8.
Int J Mol Sci ; 22(4)2021 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-33668676

RESUMEN

Biopolymer composites based on silk fibroin have shown widespread potential due to their brilliant applications in tissue engineering, medicine and bioelectronics. In our present work, biocomposite nanofilms with different special topologies were obtained through blending silk fibroin with crystallizable poly(L-lactic acid) (PLLA) at various mixture rates using a stirring-reflux condensation blending method. The microstructure, phase components, and miscibility of the blended films were studied through thermal analysis in combination with Fourier-transform infrared spectroscopy and Raman analysis. X-ray diffraction and scanning electron microscope were also used for advanced structural analysis. Furthermore, their conformation transition, interaction mechanism, and thermal stability were also discussed. The results showed that the hydrogen bonds and hydrophobic interactions existed between silk fibroin (SF) and PLLA polymer chains in the blended films. The secondary structures of silk fibroin and phase components of PLLA in composites vary at different ratios of silk to PLLA. The ß-sheet content increased with the increase of the silk fibroin content, while the glass transition temperature was raised mainly due to the rigid amorphous phase presence in the blended system. This results in an increase in thermal stability in blended films compared to the pure silk fibroin films. This study provided detailed insights into the influence of synthetic polymer phases (crystalline, rigid amorphous, and mobile amorphous) on protein secondary structures through blending, which has direct applications on the design and fabrication of novel protein-synthetic polymer composites for the biomedical and green chemistry fields.


Asunto(s)
Materiales Biocompatibles/química , Fibroínas/química , Membranas Artificiales , Nanocompuestos/química , Poliésteres/química
9.
Molecules ; 26(15)2021 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-34361653

RESUMEN

Electrically responsive biomaterials are an important and emerging technology in the fields of biomedical and material sciences. A great deal of research explores the integral role of electrical conduction in normal and diseased cell biology, and material scientists are focusing an even greater amount of attention on natural and hybrid materials as sources of biomaterials which can mimic the properties of cells. This review establishes a summary of those efforts for the latter group, detailing the current materials, theories, methods, and applications of electrically conductive biomaterials fabricated from protein polymers and polysaccharides. These materials can be used to improve human life through novel drug delivery, tissue regeneration, and biosensing technologies. The immediate goal of this review is to establish fabrication methods for protein and polysaccharide-based materials that are biocompatible and feature modular electrical properties. Ideally, these materials will be inexpensive to make with salable production strategies, in addition to being both renewable and biocompatible.


Asunto(s)
Materiales Biocompatibles/química , Polisacáridos/química , Proteínas/química , Materiales Biomiméticos , Conductividad Eléctrica , Ingeniería de Tejidos/métodos
10.
Macromol Rapid Commun ; 41(21): e2000199, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32588521

RESUMEN

Stimuli-responsive semi-interpenetrating polymer network (semi-IPN) hydrogels form an important class of polymers for their tunable properties via molecular design. They are widely investigated for a diverse range of applications including drug delivery, sensors, actuators, and osmotic agents. However, in-depth studies on some of the critical design principles affecting diffusion/leaching of linear polymer from semi-IPN hydrogels are lacking. Herein, for the first time, by preparing a series of model semi-IPN hydrogels based on thermally responsive poly (N-isopropyl acrylamide) (PNIPAM) network and linear poly(sodium acrylate) (PSA), a systematic and quantitative study concerning linear polymer chain retention and swelling/deswelling kinetics is reported. The study shows that PSA retention is significantly affected not only by PSA molecular weight and concentration, but also by polymerization temperature, which could be linked to homogeneity and internal morphology of the hydrogel. Surprisingly, there is no obvious influence of crosslinking density of PNIPAM network toward PSA retention, while faster swelling and deswelling at higher crosslinking density are observed in terms of swelling rate constant and deswelling activation energy. These findings offer new insights on the factors affecting structural and physicochemical properties of such semi-IPN hydrogels, which should in turn serve as a general guideline for materials design.


Asunto(s)
Hidrogeles , Polímeros de Estímulo Receptivo , Polimerizacion , Polímeros , Temperatura
11.
J Asian Nat Prod Res ; 22(6): 509-520, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30963782

RESUMEN

Two new xanthones smilone A (1), smilone B (2), and a new lignin smilgnin A (3) were isolated from the rhizomes of Smilax china L., together with three known xanthones (4-6), four lignins (7-10), two flavones (11, 12), two stilbenoids (13, 14), and ten organic phenoloids (15-24). Of them, compounds 4-6 were isolated from the genus Smilax for the first time. The structures of 1-24 were elucidated by the extensive analysis of spectral data and compared with the literature. All compounds were evaluated for their inhibitory effects against LPS-induced NO production in RAW264.7 macrophages. Among them, compound 24 exhibited significant inhibitory activity against NO production (IC50 = 1.26 µM), while compounds 3, 6, and 7 showed weak activities at the concentration of 50 µM.[Formula: see text].


Asunto(s)
Smilax , Xantonas , China , Lignina , Estructura Molecular
12.
Int J Mol Sci ; 21(20)2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-33066665

RESUMEN

This study investigates combining the good biocompatibility and flexibility of silk protein with three types of widely used magnetic nanoparticles to comparatively explore their structures, properties and potential applications in the sustainability and biomaterial fields. The secondary structure of silk protein was quantitatively studied by infrared spectroscopy. It was found that magnetite (Fe3O4) and barium hexaferrite (BaFe12O19) can prohibit ß-sheet crystal due to strong coordination bonding between Fe3+ ions and carboxylate ions on silk fibroin chains where cobalt particles showed minimal effect. This was confirmed by thermal analysis, where a high temperature degradation peak was found above 640 °C in both Fe3O4 and BaFe12O19 samples. This was consistent with the magnetization studies that indicated that part of the Fe in the Fe3O4 and BaFe12O19 was no longer magnetic in the composite, presumably forming new phases. All three types of magnetic composites films maintained high magnetization, showing potential applications in MRI imaging, tissue regeneration, magnetic hyperthermia and controlled drug delivery in the future.


Asunto(s)
Materiales Biocompatibles/química , Fibroínas/química , Nanopartículas de Magnetita/química , Bario/química , Materiales Biocompatibles/normas , Cobalto/química , Hierro/química , Nanopartículas de Magnetita/clasificación , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta
13.
Int J Mol Sci ; 21(11)2020 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-32512793

RESUMEN

Electrospinning has gained constant enthusiasm and wide interest as a novel sustainable material processing technique due to its ease of operation and wide adaptability for fabricating eco-friendly fibers on a nanoscale. In addition, the device working parameters, spinning solution properties, and the environmental factors can have a significant effect on the fibers' morphology during electrospinning. This review summarizes the newly developed principles and influence factors for electrospinning technology in the past five years, including these factors' interactions with the electrospinning mechanism as well as its most recent applications of electrospun natural or sustainable composite materials in biology, environmental protection, energy, and food packaging materials.


Asunto(s)
Materiales Biocompatibles/química , Biotecnología , Fenómenos Químicos , Embalaje de Alimentos , Biotecnología/métodos , Electroquímica/métodos
14.
Int J Mol Sci ; 21(13)2020 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-32630158

RESUMEN

Blended biocomposites created from the electrostatic and hydrophobic interactions between polysaccharides and structural proteins exhibit useful and unique properties. However, engineering these biopolymers into applicable forms is challenging due to the coupling of the material's physicochemical properties to its morphology, and the undertaking that comes with controlling this. In this particular study, numerous properties of the Bombyx mori silk and microcrystalline cellulose biocomposites blended using ionic liquid and regenerated with various coagulation agents were investigated. Specifically, the relationship between the composition of polysaccharide-protein bio-electrolyte membranes and the resulting morphology and ionic conductivity is explored using numerous characterization techniques, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray scattering, atomic force microscopy (AFM) based nanoindentation, and dielectric relaxation spectroscopy (DRS). The results revealed that when silk is the dominating component in the biocomposite, the ionic conductivity is higher, which also correlates with higher ß-sheet content. However, when cellulose becomes the dominating component in the biocomposite, this relationship is not observed; instead, cellulose semicrystallinity and mechanical properties dominate the ionic conduction.


Asunto(s)
Celulosa/química , Seda/química , Rastreo Diferencial de Calorimetría , Coagulantes , Espectroscopía Dieléctrica , Interacciones Hidrofóbicas e Hidrofílicas , Líquidos Iónicos , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Termogravimetría
15.
Molecules ; 25(15)2020 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-32722182

RESUMEN

Natural biomacromolecules such as structural proteins and polysaccharides are composed of the basic building blocks of life: amino acids and carbohydrates. Understanding their molecular structure, self-assembly and interaction in solvents such as ionic liquids (ILs) is critical for unleashing a flora of new materials, revolutionizing the way we fabricate multi-structural and multi-functional systems with tunable physicochemical properties. Ionic liquids are superior to organic solvents because they do not produce unwanted by-products and are considered green substitutes because of their reusability. In addition, they will significantly improve the miscibility of biopolymers with other materials while maintaining the mechanical properties of the biopolymer in the final product. Understanding and controlling the physicochemical properties of biopolymers in ionic liquids matrices will be crucial for progress leading to the ability to fabricate robust multi-level structural 1D fiber materials. It will also help to predict the relationship between fiber conformation and protein secondary structures or carbohydrate crystallinity, thus creating potential applications for cell growth signaling, ionic conductivity, liquid diffusion and thermal conductivity, and several applications in biomedicine and environmental science. This will also enable the regeneration of biopolymer composite fiber materials with useful functionalities and customizable options critical for additive manufacturing. The specific capabilities of these fiber materials have been shown to vary based on their fabrication methods including electrospinning and post-treatments. This review serves to provide basic knowledge of these commonly utilized protein and polysaccharide biopolymers and their fiber fabrication methods from various ionic liquids, as well as the effect of post-treatments on these fiber materials and their applications in biomedical and pharmaceutical research, wound healing, environmental filters and sustainable and green chemistry research.


Asunto(s)
Líquidos Iónicos/química , Polisacáridos/química , Proteínas/química , Materiales Biocompatibles/química , Biopolímeros/química , Tecnología Química Verde , Conformación Molecular , Solventes/química , Ingeniería de Tejidos
16.
Biomacromolecules ; 20(9): 3283-3293, 2019 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-31033284

RESUMEN

Integrating multifunctionality such as stretchability, adhesiveness, and electroconductivity on a single protein hydrogel is highly desirable for various applications, and remains a challenge. Here we present the development of such multifunctional hydrogels based on resilin, a natural rubber-like material with remarkable extensibility and resilience. First, genetically engineered reslin-like proteins (RLPs) with varying molecular weight were biosynthesized to tune mechanical strength and stiffness of the cross-linked RLP hydrogels. Second, glycerol was incorporated into the hydrogels to endow adhesive properties. Next, a graphene-RLP conjugate was synthesized for cross-linking with the unmodified, pristine RLP to form an integrated network. The obtained hybrid hydrogel could be stretched to over four times of its original length, and self-adhered to diverse substrate surfaces due to its high adhesion strength of ∼24 kPa. Furthermore, the hybrid hydrogel showed high sensitivity, with a gauge factor of 3.4 at 200% strain, and was capable of real-time monitoring human activities such as finger bending, swallowing, and phonating. Due to these favorable attributes, the graphene/resilin hybrid hydrogel was a promising material for use in wearable sensors. In addition, the above material design and functionalization strategy may provide intriguing opportunities to generate innovative materials for broad applications.


Asunto(s)
Técnicas Biosensibles , Hidrogeles/química , Proteínas de Insectos/biosíntesis , Goma/química , Adhesivos/síntesis química , Adhesivos/química , Conductividad Eléctrica , Humanos , Hidrogeles/síntesis química , Proteínas de Insectos/química , Peso Molecular , Goma/síntesis química , Dispositivos Electrónicos Vestibles
17.
J Fluoresc ; 29(6): 1291-1300, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31707509

RESUMEN

Development of metallic and nonmetallic heteroatom doped carbon dots have gained attention due to their enhanced physicochemical and photoluminescence properties. In this study, a facile one pot hydrothermal carbonisation approach was taken to synthesise nitrogen, aluminum co-doped carbon dots (N/Al-CDs) with a photoluminescence quantum yield of 28.7%. Durian shell, a cellulose biomass waste, was used as the primary carbon source and compared to previously reported cellulose based carbon dots, this study presents one of the highest quantum yields. The structural and fluorescent properties of the synthesised N/Al-CDs were characterized through X-ray photoelectron spectroscopy (XPS), fluorescence spectra, and Fourier transform infrared spectroscopy (FTIR). The maximum emission was at 415 nm upon excitation at 345 nm. The synthesised N/Al-CDs were resistant to photobleaching and highly photostable within the pH, ionic strength and temperature variations investigated. The transmission electron microscopy (TEM) images showed particles were quasi-spherical and well dispersed with an average diameter of 10.0 nm. Further, the N/Al-CDs was developed as a fluorescence sensor for highly selective and sensitive detection of Mn (VII) ions. A linear relationship was developed over a concentration range of 0-100 µM while the limit of detection was 46.8 nM. Application of the sensor for detection of Manganese (VII) to two real water samples showed relative standard deviation was less than 3.9% and 1.3%, respectively.


Asunto(s)
Celulosa/química , Fluorescencia , Colorantes Fluorescentes/química , Manganeso/análisis , Puntos Cuánticos/química , Aluminio/química , Carbono/química , Colorantes Fluorescentes/síntesis química , Nitrógeno/química , Tamaño de la Partícula , Propiedades de Superficie
18.
J Med Internet Res ; 21(6): e13594, 2019 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-31254336

RESUMEN

BACKGROUND: For many years, clinicians have been seeking for objective pain assessment solutions via neuroimaging techniques, focusing on the brain to detect human pain. Unfortunately, most of those techniques are not applicable in the clinical environment or lack accuracy. OBJECTIVE: This study aimed to test the feasibility of a mobile neuroimaging-based clinical augmented reality (AR) and artificial intelligence (AI) framework, CLARAi, for objective pain detection and also localization direct from the patient's brain in real time. METHODS: Clinical dental pain was triggered in 21 patients by hypersensitive tooth stimulation with 20 consecutive descending cold stimulations (32°C-0°C). We used a portable optical neuroimaging technology, functional near-infrared spectroscopy, to gauge their cortical activity during evoked acute clinical pain. The data were decoded using a neural network (NN)-based AI algorithm to classify hemodynamic response data into pain and no-pain brain states in real time. We tested the performance of several networks (NN with 7 layers, 6 layers, 5 layers, 3 layers, recurrent NN, and long short-term memory network) upon reorganized data features on pain diction and localization in a simulated real-time environment. In addition, we also tested the feasibility of transmitting the neuroimaging data to an AR device, HoloLens, in the same simulated environment, allowing visualization of the ongoing cortical activity on a 3-dimensional brain template virtually plotted on the patients' head during clinical consult. RESULTS: The artificial neutral network (3-layer NN) achieved an optimal classification accuracy at 80.37% (126,000/156,680) for pain and no pain discrimination, with positive likelihood ratio (PLR) at 2.35. We further explored a 3-class localization task of left/right side pain and no-pain states, and convolutional NN-6 (6-layer NN) achieved highest classification accuracy at 74.23% (1040/1401) with PLR at 2.02. CONCLUSIONS: Additional studies are needed to optimize and validate our prototype CLARAi framework for other pains and neurologic disorders. However, we presented an innovative and feasible neuroimaging-based AR/AI concept that can potentially transform the human brain into an objective target to visualize and precisely measure and localize pain in real time where it is most needed: in the doctor's office. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/13594.


Asunto(s)
Inteligencia Artificial/normas , Realidad Aumentada , Encéfalo/fisiopatología , Espectroscopía Infrarroja Corta/métodos , Adulto , Estudios de Factibilidad , Humanos , Dolor/diagnóstico , Dimensión del Dolor/normas
19.
Int J Mol Sci ; 21(1)2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31888066

RESUMEN

The combination of protein and polysaccharides with magnetic materials has been implemented in biomedical applications for decades. Proteins such as silk, collagen, and elastin and polysaccharides such as chitosan, cellulose, and alginate have been heavily used in composite biomaterials. The wide diversity in the structure of the materials including their primary monomer/amino acid sequences allow for tunable properties. Various types of these composites are highly regarded due to their biocompatible, thermal, and mechanical properties while retaining their biological characteristics. This review provides information on protein and polysaccharide materials combined with magnetic elements in the biomedical space showcasing the materials used, fabrication methods, and their subsequent applications in biomedical research.


Asunto(s)
Materiales Biocompatibles/química , Polisacáridos/química , Proteínas/química , Animales , Sistemas de Liberación de Medicamentos , Humanos , Fenómenos Magnéticos , Nanomedicina , Ingeniería de Tejidos
20.
Chemistry ; 24(39): 9754-9759, 2018 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-29770977

RESUMEN

Small peptides capable of assembling into well-defined nanostructures have attracted extensive attention due to their interesting applications as biomaterials. This work reports the first example of a pillararene functionalized with a guanidiniocarbonyl pyrrole (GCP)-conjugated short peptide segment. The obtained amphiphilic peptide 1 spontaneously self-assembles into a supramolecular ß-sheet in aqueous solution based on host-guest interaction between pillararene and GCP unit as well as hydrogen-bonding between the peptide strands. Interestingly, peptide 1 at low concentration shows transitions from small particles to "pearl necklace" assemblies, and finally to branched fibers in a time-dependent process. At higher concentration, it directly assembles into twisted ß-sheet tapes. Notably, without pillararene moiety, the control peptide A forms α-helix structure with morphology changing from particles to bamboo-like assemblies depending on concentration, indicating a significant role of the pillararene-GCP host-guest interaction for the secondary structure formation. Moreover, peptide 1 can serve as an efficient gene transfection vector.


Asunto(s)
Materiales Biocompatibles/química , Nanoestructuras/química , Péptidos/química , Enlace de Hidrógeno , Conformación Proteica en Lámina beta , Pirroles , Transfección
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