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1.
Analyst ; 146(5): 1620-1625, 2021 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-33599635

RESUMEN

Nanoparticles are often used to serve as drug delivery systems to improve the therapeutic efficacy of some hydrophobic drugs. In this work, PEG and peptide-modified titanium phosphate nanoparticles (TiP-PEG/peptide) were synthesized to enhance the drug delivery efficacy of tirucalla-8,24-diene-3ß,11ß-diol-7-one (KS-01), a major bioactive and hydrophobic component extracted from Euphorbia kansui. This drug delivery system with a loading efficiency of about 29.8 mg KS-01/1 g TiP-PEG/peptide exerted a significantly lower cell viability rate of MCF-7 than free KS-01, indicating that these carriers can effectively increase the therapeutic efficacy by improving its water solubility. Moreover, according to the fluorescence intensity of FAM which can be generated by caspase-3 cleaving DEVD-embedded peptide, the caspase-3 level could be determined and the therapeutic efficacy could be visualized in real time.


Asunto(s)
Euphorbia , Nanopartículas , Preparaciones Farmacéuticas , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Proteínas de Transporte de Fosfato , Polietilenglicoles , Titanio
2.
Int J Biol Macromol ; 275(Pt 2): 133651, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38972656

RESUMEN

When PBAT used as film, stability deteriorates under sunlight exposure, the poor barrier and antibacterial properties are also limiting its application. In this work, lignin-ZnO nanoparticles were prepared by hydrothermal method, as additives to fill the PBAT matrix. In addition, PBAT-lignin-ZnO composite films were successfully prepared by melting and hot-pressing method. It is found that lignin could well dispersed the ZnO when its implantation into PBAT films, and lignin-ZnO not only maintaining tensile strength and thermal stability, but also could prompt PBAT's crystallinity. Especially, P-L-ZnO-2 composite films have good photostability. After 60 h aging, it can still maintain good molecular weight, chemical structure and mechanical properties. Besides, these composite films have improved hydrophobicity, barrier and antibacterial properties, could prevent mildew and significantly reduce the weight loss rate, color difference and hardness changes of strawberries during storage. This work provides a potential film material for outdoor applications and food packaging.


Asunto(s)
Antibacterianos , Embalaje de Alimentos , Lignina , Óxido de Zinc , Embalaje de Alimentos/métodos , Óxido de Zinc/química , Óxido de Zinc/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Lignina/química , Resistencia a la Tracción , Nanocompuestos/química , Interacciones Hidrofóbicas e Hidrofílicas , Staphylococcus aureus/efectos de los fármacos
3.
ACS Appl Bio Mater ; 7(6): 3758-3765, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38768375

RESUMEN

Drug-resistant bacteria present a grave threat to human health. Fluorescence imaging-guided photodynamic antibacterial therapy holds enormous potential as an innovative treatment in antibacterial therapy. However, the development of a fluorescent material with good water solubility, large Stokes shift, bacterial identification, and high photodynamic antibacterial efficiency remains challenging. In this study, we successfully synthesized an amphiphilic aggregation-induced emission (AIE) fluorescent probe referred to as NPTPA-QM. This probe possesses the ability to perform live-bacteria fluorescence imaging while also exhibiting antibacterial activity, specifically against Staphylococcus aureus (S. aureus). We demonstrate that NPTPA-QM can eliminate S. aureus at a very low concentration (2 µmol L-1). Moreover, it can effectively promote skin wound healing. Meanwhile, this NPTPA-QM exhibits an excellent imaging ability by simple mixing with S. aureus. In summary, this research presents a straightforward and highly effective method for creating "amphiphilic" AIE fluorescent probes with antibacterial properties. Additionally, it offers a rapid approach for imaging bacteria utilizing red emission.


Asunto(s)
Antibacterianos , Materiales Biocompatibles , Colorantes Fluorescentes , Ensayo de Materiales , Pruebas de Sensibilidad Microbiana , Imagen Óptica , Tamaño de la Partícula , Staphylococcus aureus , Staphylococcus aureus/efectos de los fármacos , Colorantes Fluorescentes/química , Colorantes Fluorescentes/farmacología , Colorantes Fluorescentes/síntesis química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/síntesis química , Estructura Molecular , Ratones , Animales , Humanos , Tensoactivos/química , Tensoactivos/farmacología , Tensoactivos/síntesis química
4.
Adv Healthc Mater ; 12(28): e2300801, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37369123

RESUMEN

The composition, elasticity, and organization of the extracellular matrix within the central nervous system contribute to the architecture and function of the brain. From an in vitro modeling perspective, soft biomaterials are needed to mimic the 3D neural microenvironments. While many studies have investigated 3D culture and neural network formation in bulk hydrogel systems, these approaches have limited ability to position cells to mimic sophisticated brain architectures. In this study, cortical neurons and astrocytes acutely isolated from the brains of rats are bioprinted in a hydrogel to form 3D neuronal constructs. Successful bioprinting of cellular and acellular strands in a multi-bioink approach allows the subsequent formation of gray- and white-matter tracts reminiscent of cortical structures. Immunohistochemistry shows the formation of dense, 3D axon networks. Calcium signaling and extracellular electrophysiology in these 3D neuronal networks confirm spontaneous activity in addition to evoked activities under pharmacological and electrical stimulation. The system and bioprinting approaches are capable of fabricating soft, free-standing neuronal structures of different bioink and cell types with high resolution and throughput, which provide a promising platform for understanding fundamental questions of neural networks, engineering neuromorphic circuits, and for in vitro drug screening.


Asunto(s)
Bioimpresión , Hidrogeles , Ratas , Animales , Hidrogeles/química , Materiales Biocompatibles/química , Neuronas , Matriz Extracelular/química , Impresión Tridimensional , Ingeniería de Tejidos , Andamios del Tejido/química
5.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2633-2643, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34313082

RESUMEN

Microplastics, a new class of environmental pollutants, accumulates in the environment at an uncontrollable rate, which threatens aquatic organisms. Plankton are the basis of food webs and play a significant role in the material circulation and energy flow of aquatic ecosystems. Plankton are sensitive to various environmental pollutants. It is necessary to investigate the impacts of microplastics on plankton. Here, we analzyed the sources and characteristics of microplastics, and the current state of microplastic pollution in aquatic ecosystem. The direct and indirect harmful effects of microplastics on aquatic organisms were elaborated. Then, we focused on the potential consequences of microplastics on phytoplankton and zooplankton species from different scales, ranging from individual, population, to community level. With respect to plankton organisms, few studies were carried out on genomics and proteomics from the microcosmic perspective, and on popu-lation and community responses from the macroscopic aspect. This review would provide references for further studies.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Organismos Acuáticos , Ecosistema , Monitoreo del Ambiente , Plancton , Plásticos/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
6.
PLoS One ; 11(4): e0154402, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27120183

RESUMEN

There is an urgent need for rapid and reliable methods able to detect melamine in animal feed. In this study, a quick, simple, and sensitive method for the determination of melamine content in animal feed was developed using surface-enhanced Raman spectroscopy on fabricated Ag nanorod (AgNR) array substrates with a one-step sample extraction procedure. The AgNR array substrates washed by HNO3 solvent (10-7 M) and methanol and showed the good stability within 6 months. The Raman shift at △ν = 682 cm-1 was used as the characteristic melamine peak in the calculations. Sufficient linearity was obtained in the 2-200 µg·g-1 range (R2 = 0.926). The limits of detection and quantification were 0.9 and 2 µg·g-1, respectively. The recovery rates were 89.7-93.3%, with coefficients of variation below 2.02%. The method showed good accuracy compared with the tradition GC-MS analysis. This new protocol only need 2 min to fininsh the detection which could be developed for rapid onsite screening of melamine contamination in quality control and market surveillance applications.


Asunto(s)
Alimentación Animal/análisis , Técnicas de Química Analítica , Nanopartículas del Metal/química , Resinas Sintéticas/análisis , Triazinas/análisis , Animales , Contaminación de Alimentos/análisis , Oro/química , Límite de Detección , Metanol , Nanotubos/química , Solventes , Espectrometría Raman/métodos
7.
PLoS One ; 9(1): e85570, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24409332

RESUMEN

With the trend of an increasing aged population worldwide, Alzheimer's disease (AD), an age-related neurodegenerative disorder, as one of the major causes of dementia in elderly people is of growing concern. Despite the many hard efforts attempted during the past several decades in trying to elucidate the pathological mechanisms underlying AD and putting forward potential therapeutic strategies, there is still a lack of effective treatments for AD. The efficacy of many potential therapeutic drugs for AD is of main concern in clinical practice. For example, large bodies of evidence show that the anti-tumor histone deacetylase (HDAC) inhibitor, suberoylanilidehydroxamic acid (SAHA), may be of benefit for the treatment of AD; however, its extensive inhibition of HDACs makes it a poor therapeutic. Moreover, the natural flavonoid, curcumin, may also have a potential therapeutic benefit against AD; however, it is plagued by low bioavailability. Therefore, the integrative effects of SAHA and curcumin were investigated as a protection against amyloid-beta neurotoxicity in vitro. We hypothesized that at low doses their synergistic effect would improve therapeutic selectivity, based on experiments that showed that at low concentrations SAHA and curcumin could provide comprehensive protection against Aß25-35-induced neuronal damage in PC12 cells, strongly implying potent synergism. Furthermore, network analysis suggested that the possible mechanism underlying their synergistic action might be derived from restoration of the damaged functional link between Akt and the CBP/p300 pathway, which plays a crucial role in the pathological development of AD. Thus, our findings provided a feasible avenue for the application of a synergistic drug combination, SAHA and curcumin, in the treatment of AD.


Asunto(s)
Péptidos beta-Amiloides/toxicidad , Curcumina/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Fármacos Neuroprotectores/farmacología , Nylons/farmacología , Pirroles/farmacología , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Animales , Apoptosis/efectos de los fármacos , Proteína de Unión a CREB/metabolismo , Supervivencia Celular/efectos de los fármacos , Progresión de la Enfermedad , Sinergismo Farmacológico , Proteína p300 Asociada a E1A/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Redes Reguladoras de Genes , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Estrés Oxidativo/efectos de los fármacos , Células PC12 , Ratas
8.
PLoS One ; 8(6): e66748, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23799131

RESUMEN

OBJECTIVE: To investigate the effect of intraventricular injection of human dental pulp stem cells (DPSCs) on hypoxic-ischemic brain damage (HIBD) in neonatal rats. METHODS: Thirty-six neonatal rats (postnatal day 7) were assigned to control, HIBD, or HIBD+DPSC groups (n = 12 each group). For induction of HIBD, rats underwent left carotid artery ligation and were exposed to 8% to 10% oxygen for 2 h. Hoechst 33324-labeled human DPSCs were injected into the left lateral ventricle 3 days after HIBD. Behavioral assays were performed to assess hypoxic-ischemic encephalopathy (HIE), and on postnatal day 45, DPSC survival was assessed and expression of neural and glial markers was evaluated by immunohistochemistry and Western blot. RESULTS: The HIBD group showed significant deficiencies compared to control on T-maze, radial water maze, and postural reflex tests, and the HIBD+DPSC group showed significant improvement on all behavioral tests. On postnatal day 45, Hoechst 33324-labeled DPSC nuclei were visible in the injected region and left cortex. Subsets of DPSCs showed immunostaining for neuronal (neuron-specific enolase [NSE], Nestin) and glial markers (glial fibrillary acidic protein [GFAP], O4). Significantly decreased staining/expression for NSE, GFAP, and O4 was found in the HBID group compared to control, and this was significantly increased in the HBID+DPSC group. CONCLUSION: Intraventricular injection of human DPSCs improves HIBD in neonatal rats.


Asunto(s)
Células Madre Adultas/trasplante , Pulpa Dental/citología , Hipoxia-Isquemia Encefálica/terapia , Adolescente , Adulto , Células Madre Adultas/fisiología , Animales , Animales Recién Nacidos , Antígenos de Diferenciación/metabolismo , Diferenciación Celular , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Hipoxia-Isquemia Encefálica/fisiopatología , Hipoxia-Isquemia Encefálica/psicología , Inyecciones Intraventriculares , Aprendizaje por Laberinto , Nestina/metabolismo , Ratas , Ratas Sprague-Dawley , Reflejo Anormal , Adulto Joven
9.
Chem Commun (Camb) ; 47(43): 11924-6, 2011 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-21975908

RESUMEN

Well-dispersed Ag@Pd supported on magnetite nanoparticles have been obtained through a simple colloidal impregnation method. The as-synthesised nanocomposite exhibits greatly enhanced catalytic reactivity and reusability towards 4-nitrophenol hydrogenation.


Asunto(s)
Óxido Ferrosoférrico/química , Nanopartículas de Magnetita/química , Paladio/química , Plata/química , Catálisis , Hidrogenación , Nanopartículas de Magnetita/ultraestructura , Nitrofenoles/química , Oxidación-Reducción , Povidona/química , Propiedades de Superficie
10.
J Nutr Biochem ; 22(10): 929-36, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21190830

RESUMEN

Oxidative stress-induced neuronal cell death has been implicated in neurodegenerative diseases; one such disease is ischemic stroke. Using reactive oxygen species (ROS)-insulted primary neurons, we screened neuroprotectants with clinical potential and then, using ischemia/reperfusion (I/R) model, investigated the anti-ischemic potential of candidate neuroprotectants. Here, we showed that luteolin, isolated from the ripe fruit of Perilla frutescens (L.) Britt, exhibited a neuroprotective action upon the in vitro platform, thus serving as candidate for in vivo pharmacological evaluation. Liposome-encapsulated luteolin produced dramatic preventing effects on I/R-induced behavioral and histological injuries after a 13-day post-ischemic treatment. Furthermore, this phytochemical not only lowered the increased level of mitochondrial ROS but also substantially up-regulated the decreased activity of catalase and glutathione in I/R rat brains. Collectively, luteolin as a neuroprotectant acts by anti-ischemic activity likely through a rebalancing of pro-oxidant/antioxidant status. Its multitarget mechanisms implicate potential effectiveness for clinically treating ischemia stroke.


Asunto(s)
Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Luteolina/uso terapéutico , Fármacos Neuroprotectores/uso terapéutico , Daño por Reperfusión/prevención & control , Animales , Animales Recién Nacidos , Antioxidantes/metabolismo , Catalasa/metabolismo , Muerte Celular , Femenino , Glutatión/metabolismo , Infarto de la Arteria Cerebral Media/complicaciones , Liposomas , Luteolina/administración & dosificación , Mitocondrias/metabolismo , Fármacos Neuroprotectores/administración & dosificación , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Daño por Reperfusión/etiología
11.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 23(6): 483-4, 488, 2005 Dec.
Artículo en Zh | MEDLINE | ID: mdl-16430175

RESUMEN

OBJECTIVE: To reconstruct 3D shape of edentulous jaw by using improved measurement system and to analyze the precision of this method. METHODS: Standard edentulous jaw models were measured with a improved measurement system by cutting and scanning layer-by-layer, and the 3D shape of the models was reconstructed by image processing with specialty software. Ten cubic plaster modes were reconstructed by the same way, data of every border before and after reconstruction were measured and analyzed. RESULTS: Data of edentulous jaw models were obtained. The errors in ten cubic before and after reconstruction were not significantly different (P > 0.05), data measured in horizontal plane were not significantly different (P > 0.05), and data measured in altitude direction were significantly different (P < 0.01), data measured after reconstruction were less than before, the error was (0.09 +/- 0.08) mm. CONCLUSION: The improved cutting and scanning measurement system can be fit for the 3D reconstruction of stomatognathic system with high precision.


Asunto(s)
Imagenología Tridimensional , Sistema Estomatognático , Humanos , Procesamiento de Imagen Asistido por Computador , Arcada Edéntula , Reproducibilidad de los Resultados , Programas Informáticos , Tomografía Computarizada por Rayos X
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