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1.
Angew Chem Int Ed Engl ; 62(39): e202306691, 2023 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-37455257

RESUMEN

Life-like hierarchical architecture shows great potential for advancing intelligent biosensing, but modular expansion of its sensitivity and functionality remains a challenge. Drawing inspiration from intracellular liquid-liquid phase separation, we discovered that a DNA-encoded artificial cell with a liquid core (LAC) can enhance peroxidase-like activity of Hemin and its DNA G-quadruplex aptamer complex (DGAH) without substrate-selectivity, unlike its gelled core (GAC) counterpart. The LAC is easily engineered as an ultrasensitive biosensing system, benefiting from DNA's high programmability and unique signal amplification capability mediated by liquid-liquid phase separation. As proof of concept, its versatility was successfully demonstrated by coupling with two molecular recognition elements to monitor tumor-related microRNA and profile cancer cell phenotypes. This scalable design philosophy offers new insights into the design of next generation of artificial cells-based biosensors.


Asunto(s)
Aptámeros de Nucleótidos , Células Artificiales , Técnicas Biosensibles , ADN Catalítico , G-Cuádruplex , MicroARNs , Neoplasias , Humanos , ADN/genética , Hemina , ADN Catalítico/metabolismo
2.
Int J Biol Macromol ; 265(Pt 2): 130793, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38503368

RESUMEN

Cellulose nanocrystals (CNCs) can form a liquid crystal film with a chiral nematic structure by evaporative-induced self-assembly (EISA). It has attracted much attention as a new class of photonic liquid crystal material because of its intrinsic, unique structural characteristics, and excellent optical properties. However, the CNCs-based photonic crystal films are generally prepared via the physical crosslinking strategy, which present water sensitivity. Here, we developed CNCs-g-PAM photonic crystal film by combining free radical polymerization and EISA. FT-IR, SEM, POM, XRD, TG-DTG, and UV-Vis techniques were employed to characterize the physicochemical properties and microstructure of the as-prepared films. The CNCs-g-PAM films showed a better thermo-stability than CNCs-based film. Also, the mechanical properties were significantly improved, viz., the elongation at break was 9.4 %, and tensile strength reached 18.5 Mpa, which was a much better enhancement than CNCs-based film. More importantly, the CNCs-g-PAM films can resist water dissolution for more than 24 h, which was impossible for the CNCs-based film. The present study provided a promising strategy to prepare CNCs-based photonic crystal film with high flexibility, water resistance, and optical properties for applications such as decoration, light management, and anti-counterfeiting.


Asunto(s)
Nanopartículas , Agua , Agua/química , Polimerizacion , Celulosa/química , Espectroscopía Infrarroja por Transformada de Fourier , Nanopartículas/química
3.
World J Clin Cases ; 12(19): 3985-3994, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38994293

RESUMEN

BACKGROUND: Myeloid sarcoma (MS), also referred to as granulocytic sarcoma or chloroma, is a rare type of extramedullary malignant tumor. MS comprises primitive granulocytic precursor cells that play a key role in the early stages of white blood cell development. Notably, the occurrence of this tumor in the gingiva is rare. CASE SUMMARY: The present study reported the case of MS with gingival swelling in the maxillary region, with aleukemic presentation in a 32-year-old male patient. Following two courses of chemotherapy, computed tomography of the region demonstrated complete clearance of the tumor. At the 12-month follow-up appointment, the patient was in a stable condition with the absence of progression. The etiology, clinical features, diagnosis, and relevant treatment of MS are discussed in the present study. CONCLUSION: Diagnosis of MS may be confirmed following histological and immunohistochemical examinations.

4.
Int J Biol Macromol ; 232: 123290, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-36682651

RESUMEN

Eco-friendly packaging material with intelligent colorimetric performance has been a requirement for food safety and quality. This work focused on a food packaging material from regenerated cellulose films that added the grape seed extract (GSE) and polyethylene glycol 200 (PEG). FTIR and SEM techniques were employed to prove the compatibility of GSE with cellulose matrix. The composite film showed an enhanced elongation at break (16.61 %) and tensile strength (33.09 MPa). The addition of PEG and GSE also improved the water contact angle of regenerated-cellulose film from 53.8° to 83.8°. Moreover, the composite films exhibited UV-blocking properties while maintaining adequate transparency. The GSE induced the regenerated films with a macroscopic change in color under different pH conditions. Furthermore, the loading of GSE slowed down the decomposition of strawberries and delayed the self-biodegradation compared with the control for more than 3 days and 18 days. The present study showed a regenerated cellulose film with acceptable mechanical and hydrophilia properties, pH-responsiveness, anti-decomposition, and delayed biodegradation performances, indicating a potential color sensor in food packaging.


Asunto(s)
Extracto de Semillas de Uva , Extracto de Semillas de Uva/química , Embalaje de Alimentos/métodos , Celulosa/química , Resistencia a la Tracción
5.
Dentomaxillofac Radiol ; 52(1): 20220081, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36279185

RESUMEN

OBJECTIVES: Cephalometric analysis is essential for diagnosis, treatment planning and outcome assessment of orthodontics and orthognathic surgery. Utilizing artificial intelligence (AI) to achieve automated landmark localization has proved feasible and convenient. However, current systems remain insufficient for clinical application, as patients exhibit various malocclusions in cephalograms produced by different manufacturers while limited cephalograms were applied to train AI in these systems. METHODS: A robust and clinically applicable AI system was proposed for automatic cephalometric analysis. First, 9870 cephalograms taken by different radiography machines with various malocclusions of patients were collected from 20 medical institutions. Then 30 landmarks of all these cephalogram samples were manually annotated to train an AI system, composed of a two-stage convolutional neural network and a software-as-a-service system. Further, more than 100 orthodontists participated to refine the AI-output landmark localizations and retrain this system. RESULTS: The average landmark prediction error of this system was as low as 0.94 ± 0.74 mm and the system achieved an average classification accuracy of 89.33%. CONCLUSIONS: An automatic cephalometric analysis system based on convolutional neural network was proposed, which can realize automatic landmark location and cephalometric measurements classification. This system showed promise in improving diagnostic efficiency in clinical circumstances.


Asunto(s)
Inteligencia Artificial , Maloclusión , Humanos , Cefalometría , Redes Neurales de la Computación , Radiografía
6.
J Microencapsul ; 29(8): 781-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22657750

RESUMEN

The effects of different loading procedures of magnetic nanoparticles (MNs) on the structure and physicochemical properties of cisplatin magnetic liposomes were investigated by X-ray diffraction, infrared spectroscopy, transmission electron microscopy, and fluorescence spectroscopy. 1, 2-Dipalmitoyl-sn-glycero-3-Phosphocholine based cisplatin magnetic liposomes were prepared using two different procedures. In procedure I, MNs were combined with phospholipids during film formation; MNs were embedded in a phospholipid bilayer. In procedure II, MNs were mixed with drugs during hydration and MNs were contained in an interior aqueous compartment. The encapsulation efficiency of cisplain and the content of MN in procedure I liposomes were 33.5% ± 3.3% and 2.34 ± 0.09 mg mL(-1), respectively. It indicated that the deliberate MN loading into the liposome structure was not only successful using procedure I, but also superior over procedure II both in cisplatin encapsulation efficiency and MN content, which can promote the magnetic targeting effect of magnetic liposomes during delivering cisplatin.


Asunto(s)
Antineoplásicos/química , Cisplatino/química , Nanopartículas , Antineoplásicos/farmacocinética , Rastreo Diferencial de Calorimetría , Cisplatino/farmacocinética , Liposomas , Magnetismo , Microscopía Electrónica de Transmisión , Espectrometría de Fluorescencia , Espectrofotometría Atómica , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
7.
Yao Xue Xue Bao ; 46(5): 592-8, 2011 May.
Artículo en Zh | MEDLINE | ID: mdl-21800550

RESUMEN

Effects of different procedures of magnetic nanoparticles into the liposome structure on the distribution of magnetic particles in the liposome were investigated. Magnetic liposomes with high-encapsulating rate of cisplatin (CDDP) were obtained. Fe3O4 magnetic nanoparticles which was modified by organic functional group on surface was synthesized by an one-step modified hydrothermal method. The CDDP magnetic liposomes were prepared by a film scattering-ultrasonic technique and the concentrations of CDDP in the liposomes were measured by graphite furnace atomic absorbance spectroscopy. Magnetic liposomes with different microstructure were prepared by the two different procedures, where the magnetic particles were combined with phospholipid before the film preparation to form liposome in procedure I, and drug solution and the magnetic particles were mixed before hydrating the lipids film to form liposome in procedure II. The liposome structure was observed by transmission electron microscope (TEM). The CDDP magnetic liposomes were prepared by the optimized method which was selected by orthogonal test. Encapsulation rate of the magnetic particles distributed in the phospholipid bilayer through the procedure I was 34.90%. While liposome, produced by the procedure II technique, contained magnetic particles in the interior aqueous compartment, which encapsulation rate was 28.34%. Encapsulation rates of both I and II were higher than that of conventional liposome. The release profile of all the three different liposomes in vitro fitted with a first-order equation. Because of distribution of magnetic particles in the phospholipid bilayer, the skeleton of phospholipid bilayer was changed. The releasing tl/2 of magnetic liposomes produced by the procedure I technique is 9 h, which is shorter than that of the other two liposomes. Assemble of magnetic nanoparticles into the structure of liposome was succeeded by the procedure I, which showed superiority than by procedure II whatever in CDDP liposome encapsulation efficiency and content of the magnetic particles and would ensure sustained-release character.


Asunto(s)
Antineoplásicos/química , Cisplatino/química , Composición de Medicamentos/métodos , Liposomas/química , Nanoconjugados/química , Antineoplásicos/administración & dosificación , Cisplatino/administración & dosificación , Óxido Ferrosoférrico/química , Nanopartículas de Magnetita/química , Nanoconjugados/administración & dosificación , Tamaño de la Partícula
8.
Infect Genet Evol ; 67: 44-50, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30347249

RESUMEN

Enterovirus 71 is the main pathogen that causes severe and fatal hand-foot-mouth-disease (HFMD) cases. As the enterovirus virus mutation has implications for pathogenesis, vaccine development, antiviral therapy, and epidemiological disease management of the virus. In this study, we investigated the variations of enterovirus 71 in thermal adaption, using the method of adaptive laboratory evolution. The sibling virus strains were isolated from a 2-year-old severe case of HFMD (#100) and her symptomless close contact (#101). Both strains were cultured in Vero cells by serial passage of 36 generations at the temperatures of 28.0 °C, 33.0 °C and 39.5 °C to construct adaptive lineages. According to the comparative analysis of phenotypes between adapted strains and parental strains, differences in growth rate were observed in the sibling lineages and a larger plaque was found mainly in the hot adapted strains for lineage #101. Two sets of adaptive strains from six time points (parental, 12th 17th, 31st, 35th passage and endpoint) were sequenced and analyzed by both Sanger sequencing and Next Generation Sequencing. Several variations in most coding genes and one reverse mutation in 5'UTR was observed, along with the identity of 99.8% for complete genome for both lineages. Notably, thermal specific non-synonymous mutations were found in the gene of VP1\VP3\3A\2C\3C. Moreover, the concurrent mutations A292G, A434G and A355C/T of sibling lineages in VP1 showed quantificational trace with distinguishing patterns for different temperatures, which were suspected to be the thermo-sensitive mutation hotspots. These results highlight the possible rules of thermal adaption in enterovirus 71, produce a novel picture of genome evolution of the virus, and shed light on viral variation and evolution.


Asunto(s)
Adaptación Biológica , Enterovirus Humano A/clasificación , Enterovirus Humano A/genética , Temperatura , Regiones no Traducidas 5' , Animales , Evolución Biológica , Células Cultivadas , Chlorocebus aethiops , Infecciones por Enterovirus/virología , Genoma Viral , Humanos , Análisis de Secuencia de ADN , Células Vero , Ensayo de Placa Viral , Replicación Viral
9.
Zhongguo Zhong Yao Za Zhi ; 32(5): 388-90, 2007 Mar.
Artículo en Zh | MEDLINE | ID: mdl-17511140

RESUMEN

OBJECTIVE: To prepare sustained-release microsphere containing extract of Sanguis Draconis and to measure its dissolution in vitro. METHOD: Sustained-release microsphere was prepared with polylactic acid (PLA) as carriers using the oil-in-water (O/W) emulsion solvent evaporation method. The powder particle's characteristics of sustainded-release microsphere were evaluated comprehensively, and its dissolution characteristics in vitro were studied. RESULT: The microsphere was round and its surface was smooth, drug-loading rate was 21.97% and the entrapment rate was 55.76%, the accumulative release percentage was 76. 71% in 16 hours. CONCLUSION: The sustained release effect of Sanguis Draconis microspheres was formed with potentially wide applications.


Asunto(s)
Arecaceae/química , Preparaciones de Acción Retardada/química , Medicamentos Herbarios Chinos/química , Microesferas , Tecnología Farmacéutica/métodos , Medicamentos Herbarios Chinos/aislamiento & purificación , Ácido Láctico/química , Tamaño de la Partícula , Plantas Medicinales/química , Poliésteres , Polímeros/química , Reproducibilidad de los Resultados , Resinas de Plantas/química
10.
Chin J Traumatol ; 8(2): 91-5, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15769307

RESUMEN

OBJECTIVE: To investigate a new method to construct tissue-engineering bone that will be applicable clinically. METHODS: The cultured 5th generation rabbit bone marrow stroma osteoblasts (MSO) was dissolved in 3% sodium alginate solution (the final concentration of sodium alginate in the solution being 1%, and MSO, 5x10(6)/L), and then inoculated into prepared true bone ceramic (TBC) and gelatinized the bone by dribbling with calcium gluconate. The standard bone defect models were made in 48 adult New Zealand rabbit's both radius. Among the 48 rabbits, 24 were in Groups A and B, in which the left radius was implanted with gelatinized MSO-TBC (Group A) and right radius implanted with autograft-bone (Group B); and the other 24 were in control group whose left radius was implanted with non-gelatinized MSO-TBC (Group C) and right radius implanted with gelatinized TBC (Group D). Outcomes of the implanted bones were assessed by radiology, pathological histology, osteogenetic quantitative analysis, and biomechanics at 2, 4, 8, 12 weeks postoperatively. RESULTS: In Groups A and B, a satisfactory bone reparation and bony union was noted within 12 weeks. In Groups C and D, bone reparation was not satisfied compared with Group A in terms of ostogenetic quantity and biomechanics. CONCLUSIONS: Gelatinized MSO-TBC is an ideal artificial active bone that overcomes TBC shortcomings of fragileness and smooth surface that is not eligible for seed cell's adhesion. It is promising to put into clinical use extensively.


Asunto(s)
Enfermedades Óseas/terapia , Células de la Médula Ósea/citología , Sustitutos de Huesos , Osteoblastos/citología , Osteoblastos/trasplante , Ingeniería de Tejidos/métodos , Animales , Biomasa , Enfermedades Óseas/diagnóstico por imagen , Enfermedades Óseas/patología , Cerámica , Modelos Animales de Enfermedad , Femenino , Gelatina , Masculino , Osteogénesis , Conejos , Radiografía , Radio (Anatomía)/diagnóstico por imagen , Radio (Anatomía)/lesiones , Radio (Anatomía)/patología , Radio (Anatomía)/cirugía , Células del Estroma/citología , Células del Estroma/trasplante , Resultado del Tratamiento
11.
Artículo en Zh | MEDLINE | ID: mdl-16200966

RESUMEN

OBJECTIVE: To test and evaluate the olfactory function of patient after total laryngectomy, seek to a practical method to ameliorate olfactory function and rise the qualitative character of these patients. METHODS: Using the T&T olfactory examination to evaluate the olfactory function of 60 cases. Four cases olfactory mucosae were observed by electron microscope. Observing relation among the remains olfaction, the time after operation and whether or not undergone the voice reconstruction. And analyse the reasons of the above hyposomnia. Using the closing-mouth and nasal out-word airflow maneuver (CNOAM) as the intervention in the patients of tracheoesophageal fistula voice reconstruction after total laryngectomy to observe the amelioration after intervention. RESULTS: It shows various degree of hyposmia and anosmia in the cases after total laryngectomy with or without tracheoesophageal fistula voice reconstruction, with significant deference (P < 0.01) compared to the normal person respectively. There are precisely correlation among the time after operation and whether or not undergone the voice reconstruction. The longer time leads to less remaining olfaction. The patients after total laryngectomy without tracheoesophageal fistula voice reconstruction have lost their olfaction thoroughly within 5 years. But for the patients after total laryngectomy with tracheoesophageal fistula voice reconstruction, they have a middle hyposmia within 5 years, with significant deference (P < 0.01) between the patients in 5 years and after 5 years. There were significant differences (P < 0.01) between the values of patients with and without tracheoesophageal fistula voice reconstruction. The ultrastructure of 4 cases of olfactory epithelium shows the apoptosis change. After the treatment of CNOAM, the remaining olfaction of most patients were improved, with significant deference (P < 0.01) compared to those before the treatment of CNOAM. CONCLUSIONS: The proceed hypofunction of olfaction may be influenced by the reform of respiratory air, the extinction of air velocity bypass the nasal cavity and the apoptosis of epithelial cells in the patients after total laryngectomy. But if we give an early intervention study such as tracheoesophageal fistula voice reconstruction and CNOAM, the olfactory function may be maintenance. During the intervention, the ending of olfactory nerves may be get uninterrupt stimulation. This may help the patients keep a better existing quality than those fail to accept the interventions.


Asunto(s)
Laringectomía/efectos adversos , Nervio Olfatorio/fisiopatología , Olfato , Adulto , Anciano , Carcinoma de Células Escamosas/fisiopatología , Estudios de Casos y Controles , Femenino , Humanos , Neoplasias Laríngeas/fisiopatología , Masculino , Persona de Mediana Edad , Periodo Posoperatorio
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