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1.
Anal Chem ; 96(6): 2550-2558, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38314707

RESUMEN

Cancer-related extracellular vesicles (EVs) are considered important biomarkers for cancer diagnosis because they can convey a large amount of information about tumor cells. In order to detect cancer-related EVs efficiently, an electrochemiluminescence (ECL) sensor for the specific identification and highly sensitive detection of EVs in the plasma of cancer patients was constructed based on dual recognitions by glycosyl-imprinted polymer (GIP) and aptamer. The characteristic glycosyl Neu5Ac-α-(2,6)-Gal-ß-(1-4)-GlcNAc trisaccharide on the surface of EVs was used as a template molecule and 3-aminophenylboronic acid as a functional monomer to form a glycosyl-imprinted polymer by electropolymerization. After glycosyl elution, the imprinted film specifically recognized and adsorbed the EVs in the sample, and then the CD63 aptamer-bipyridine ruthenium (Aptamer-Ru(bpy)) was added to combine with the CD63 glycoprotein on the extracellular vesicle's surface, thus providing secondary recognition of the EVs. Finally, the EVs were quantitatively detected according to the ECL signal produced by the labeled bipyridine ruthenium. When more EVs were captured by the imprinted film, more probes were obtained after incubation, and the ECL signal was stronger. Under the optimized conditions, the ECL signal showed a good linear relationship with the concentration of EVs in the range of 9.5 × 102 to 9.5 × 107 particles/mL, and the limit of detection was 641 particles/mL. The GIP sensor can discriminate between the EV contents of cancer patients and healthy controls with high accuracy. Because of its affordability, high sensitivity, and ease of use, it is anticipated to be employed for cancer early detection and diagnosis.


Asunto(s)
Técnicas Biosensibles , Vesículas Extracelulares , Neoplasias , Rutenio , Humanos , Mediciones Luminiscentes , Oligonucleótidos , Polímeros , Técnicas Electroquímicas , Neoplasias/diagnóstico
2.
J Nanobiotechnology ; 22(1): 321, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38849841

RESUMEN

Acute lung injury (ALI) is a life threatening disease in critically ill patients, and characterized by excessive reactive oxygen species (ROS) and inflammatory factors levels in the lung. Multiple evidences suggest that nanozyme with diversified catalytic capabilities plays a vital role in this fatal lung injury. At present, we developed a novel class of polydopamine (PDA) coated cerium dioxide (CeO2) nanozyme (Ce@P) that acts as the potent ROS scavenger for scavenging intracellular ROS and suppressing inflammatory responses against ALI. Herein, we aimed to identify that Ce@P combining with NIR irradiation could further strengthen its ROS scavenging capacity. Specifically, NIR triggered Ce@P exhibited the most potent antioxidant and anti-inflammatory behaviors in lipopolysaccharide (LPS) induced macrophages through decreasing the intracellular ROS levels, down-regulating the levels of TNF-α, IL-1ß and IL-6, up-regulating the level of antioxidant cytokine (SOD-2), inducing M2 directional polarization (CD206 up-regulation), and increasing the expression level of HSP70. Besides, we performed intravenous (IV) injection of Ce@P in LPS induced ALI rat model, and found that it significantly accumulated in the lung tissue for 6 h after injection. It was also observed that Ce@P + NIR presented the superior behaviors of decreasing lung inflammation, alleviating diffuse alveolar damage, as well as promoting lung tissue repair. All in all, it has developed the strategy of using Ce@P combining with NIR irradiation for the synergistic enhanced treatment of ALI, which can serve as a promising therapeutic strategy for the clinical treatment of ROS derived diseases as well.


Asunto(s)
Lesión Pulmonar Aguda , Cerio , Indoles , Polímeros , Especies Reactivas de Oxígeno , Cerio/química , Cerio/farmacología , Animales , Lesión Pulmonar Aguda/tratamiento farmacológico , Polímeros/química , Polímeros/farmacología , Indoles/química , Indoles/farmacología , Especies Reactivas de Oxígeno/metabolismo , Ratas , Ratones , Masculino , Células RAW 264.7 , Pulmón/efectos de los fármacos , Pulmón/patología , Antioxidantes/farmacología , Antioxidantes/química , Ratas Sprague-Dawley , Lipopolisacáridos/farmacología , Antiinflamatorios/farmacología , Antiinflamatorios/química , Rayos Infrarrojos , Depuradores de Radicales Libres/farmacología , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/uso terapéutico , Nanopartículas/química , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Citocinas/metabolismo
3.
Am J Orthod Dentofacial Orthop ; 156(2): 210-219, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31375231

RESUMEN

INTRODUCTION: More patients are choosing customized orthodontic appliances because of their excellent esthetics. It is essential that clinicians understand the biomechanics of the tooth movement tendency in customized lingual orthodontics. This study aimed to evaluate the tooth movement tendency during space closure in maxillary anterior teeth with the use of miniscrew anchorage in customized lingual orthodontics with various power arm locations. METHODS: Three-dimensional finite element models of the maxilla were created with miniscrews and power arms; the positions were varied to change the force directions. A retraction force (1.5 N) was applied from the top of the miniscrews to the selected points on the power arm, and the initial displacements of the reference nodes of the maxillary teeth were analyzed. RESULTS: After applying force in different directions, power arms located at the distal side of the canines led to larger initial lingual crown tipping and occlusal crown extrusion of the maxillary incisors compared with power arms located at the midpoint between the lateral incisors and canines, and caused a decreasing trend of the intercanine width. CONCLUSIONS: In customized lingual orthodontic treatment, power arms located at the distal side of the canines are unfavorable for anterior teeth torque control and intercanine width control. Power arms located at the midpoint between the lateral incisors and canines can get better torque control, but still cannot achieve excepted torque without extra torque control methods, no matter whether its force application point is higher than, lower than, or equal to the level of the top of the miniscrews.


Asunto(s)
Tornillos Óseos , Análisis de Elementos Finitos , Métodos de Anclaje en Ortodoncia/instrumentación , Métodos de Anclaje en Ortodoncia/métodos , Cierre del Espacio Ortodóncico , Técnicas de Movimiento Dental/instrumentación , Técnicas de Movimiento Dental/métodos , Adulto , Fenómenos Biomecánicos , Simulación por Computador , Diente Canino/patología , Humanos , Imagenología Tridimensional/métodos , Incisivo/patología , Maxilar , Modelos Biológicos , Diseño de Aparato Ortodóncico , Aparatos Ortodóncicos , Soportes Ortodóncicos , Cierre del Espacio Ortodóncico/instrumentación , Cierre del Espacio Ortodóncico/métodos , Alambres para Ortodoncia , Planificación de Atención al Paciente , Estrés Mecánico , Corona del Diente , Torque , Resultado del Tratamiento
4.
J Mater Sci Mater Med ; 28(7): 99, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28534282

RESUMEN

Modified supersaturated phosphate buffer solutions were used to synthesize phosphate-based spheres, including calcium phosphate (CaP), strontium phosphate (SrP) and barium phosphate (BaP). A series of ions concentrations in the modified phosphate buffer solutions were investigated in order to study their effects in precipitates morphologies. During synthesis, it was found that magnesium was the key factor in sphere formation. The morphologies of calcium phosphate, strontium phosphate and barium phosphate precipitates varied as the concentration of magnesium ions varied. When sufficient magnesium was provided, the precipitates appeared spherical, and the diameter was in range of 0.5-2 µm. The morphologies, compositions and structure of spheres were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N2 adsorption analysis. Moreover, the application of magnesium substituted calcium phosphate spheres in dentin tubules occlusion was investigated.


Asunto(s)
Fosfatos de Calcio/química , Cápsulas/síntesis química , Cápsulas/aislamiento & purificación , Precipitación Química , Composición de Medicamentos/métodos , Microesferas , Tampones (Química) , Tamaño de la Partícula , Soluciones/química
5.
Antibiotics (Basel) ; 10(9)2021 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-34572628

RESUMEN

Dental fluorosis (DF) is an endemic disease caused by excessive fluoride exposure during childhood. Previous studies mainly focused on the acid resistance of fluorotic enamel and failed to reach a consensus on the topic of the caries susceptibility of DF patients. In this review, we discuss the role of DF classification in assessing this susceptibility and follow the "four factors theory" in weighing the pros and cons of DF classification in terms of host factor (dental enamel and saliva), food factor, bacteria factor, and DF treatment factor. From our analysis, we find that susceptibility is possibly determined by various factors such as the extent of structural and chemical changes in fluorotic enamel, eating habits, fluoride levels in diets and in the oral cavity, changes in quantity and quality of saliva, and/or oral hygiene. Thus, a universal conclusion regarding caries susceptibility might not exist, instead depending on each individual's situation.

6.
Zool Res ; 41(6): 734-740, 2020 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-33058571

RESUMEN

A new species of the genus Amolops, Amolopsputaoensissp. nov., is described from northern Myanmar. The new species can be distinguished from its congeners by the following characters: (1) dorsolateral fold distinct; (2) upper-lip stripe white; (3) male body size 37.6-40.2 mm; (4) ground color of dorsal surface brown, flank green, small warts on dorsum; (5) two internal subgular vocal sacs present; (6) HL slightly shorter than HW; (7) two palmar tubercles present, supernumerary tubercles and outer metatarsal tubercle absent; (8) tympanum smaller than half of eye diameter; (9) vomerine teeth present; (10) tibiotarsal articulation reaching beyond snout tip; (11) supratympanic fold indistinct; (12) pineal body present; (13) finger webbing absent, presence of circummarginal groove on tip of first finger; (14) nuptial pads present. The population from Myanmar represented a distinct maternal lineage within the Amolops monticola group and was recovered as a sister taxon to Amolops aniqiaoensis with strong support (100) based on concatenated data. Average uncorrected pairwise distances ( P-distances) between the specimens from Myanmar and other species in the genus ranged from 2.69% (vs. A. aniqiaoensis) to 12.24% (vs. A. indoburmanensis) for 16S rRNA, 6.14% (vs. A. aniqiaoensis) to 15.79% (vs. A. panhai) for COI, and 9.66% (vs. A. aniqiaoensis) to 19.52% (vs. A. afghanus) for ND2.


Asunto(s)
Ranidae/clasificación , Distribución Animal , Animales , Masculino , Mianmar , Filogenia , Ranidae/fisiología , Especificidad de la Especie
7.
Int J Biol Macromol ; 143: 393-400, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31830456

RESUMEN

In previous researches, the results showed that selenium Hericium erinaceus polysaccharide and Hericium erinaceus polysaccharide-loaded poly (lactic-co-glycolic acid) nanoparticles enhanced immune responses. In order to further enhance the immune adjuvant activity and phagocytosis of the nanoparticles, two way of combination (selenium-HEP loaded PLGA nanoparticles and selenium modified HEP-PLGA nanoparticles) were prepared to investigate the effects on macrophages in vitro. After treatment with the nanoparticles, the effects of phagocytosis, co-stimulatory molecules expression, nitric oxide (NO), and cytokines secretion were evaluated. The results showed that the particle size, PDI and zeta potential of the selenium-HEP loaded PLGA nanoparticles (Se-HEP-PLGA) and selenium modifified HEP-PLGA nanoparticles (HEP-PLGA-Se) were presented. Se-HEP-PLGA and HEP-PLGA-Se nanoparticles significantly stimulated phagocytic activity, CD40 and CD86 expression of macrophages. In addition, the levels of NO, TNF-α, IL-1ß and IL-6 were enhanced in the peritoneal macrophages by stimulation with Se-HEP-PLGA and HEP-PLGA-Se nanoparticles. Among them, Se-HEP-PLGA showed the best effects on the expression of co-stimulatory molecules, secretions of NO and cytokines. These results indicated that Se-HEP-PLGA could enhance the activation of macrophages, and it could be potentially used as an HEP delivery system for the induction of strong immune responses.


Asunto(s)
Basidiomycota/química , Inmunidad Celular/efectos de los fármacos , Nanopartículas/química , Polisacáridos/farmacología , Adyuvantes Inmunológicos/farmacología , Sistemas de Liberación de Medicamentos , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/inmunología , Humanos , Macrófagos/efectos de los fármacos , Óxido Nítrico/genética , Fagocitosis/efectos de los fármacos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacología , Polisacáridos/química , Selenio/química , Factor de Necrosis Tumoral alfa/genética
8.
Zootaxa ; 4615(3): zootaxa.4615.3.11, 2019 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-31716339

RESUMEN

Opsarius putaoensis, new species, is described from the Mali Hka River, a tributary of the Irrawaddy River in northern Myanmar. For convenience of identification, Opsarius sensu Rainboth (1991) in Southeast Asia and India can be divided into two species groups based on the number of anal-fin rays: (1) the O. gatensis species group with more than 12 branched anal-fin rays, and (2) the O. barna species group with fewer than 11 branched anal-fin rays. The remaining species of the O. barna species group can be divided into two species subgroups by the presence or absence of barbels: (1) the O. chatricensis species subgroup without barbels, and (2) the O. barnoides species subgroup with one or two pairs of barbels. Opsarius putaoensis sp. nov. is a member of the O. chatricensis species subgroup together with O. chatricensis, O. arunachalensis, and O. barna. Opsarius putaoensis is most similar to O. chatricensis in overall appearance, including the number of vertical bars and color pattern, but it differs from O. chatricensis by the following characters: insertion of dorsal not reaching posterior end of pelvic fin base vs. reaching, vertical bars 6-7 vs. 7-8, vertical bars extending to the lateral line vs. not, branched anal-fin rays 9 vs. 10, branched pelvic-fin rays 7 vs. 8, branched pectoral-fin rays 12, rarely 11 vs. 11, circumpeduncular scales 12 vs. 14, and scale rows between dorsal-fin origin and lateral line 7-8 vs. 6. It is distinguished from all other species of the genus Opsarius by a combination of the following characters: barbels absent, dentary with parallel rows of tubercles, snout much shorter than eye diameter, mouth gape below anterior edge of orbit, body deep with depth 25.6-33.3% SL, pectoral and pelvic axial scales lobate, lateral line completely perforated with 35-38 scales, scale rows between dorsal-fin origin and lateral line 7-8, predorsal scales 15, circumpeduncular scales 12, branched dorsal-fin rays 7, branched anal-fin rays 9, branched pelvic-fin rays 7, insertion of dorsal not reaching pelvic-fin base, body with 6-7 vertical bars, extending to lateral line, and distal edge of dorsal fin black.


Asunto(s)
Cyprinidae , Animales , Color , India , Mianmar , Ríos
9.
Int J Biol Macromol ; 118(Pt A): 932-937, 2018 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-29966670

RESUMEN

In present study, HEP was successfully encapsulated into the Poly (lactic-coglycolicacid) (PLGA) to constitute the HEP-PLGA. The effects of three independent factors (the proper range of ratio of organic phase (o) to internal water phase (w1) (X1), ratio of external water phase (w2) to the primary emulsion (PE) (X2), and the concentration of PLGA (X3) on the extraction yield of encapsulation efficiency (EE) from the HEP was optimized using response surface methodology. The optimal extraction conditions for HEP-PLGA were determined as follows: X1: 8:1, X2: 7:1 and X3: 20 mg·mL-1. Under these optimal conditions, the mean experimental EE 90.86 ±â€¯0.576% was corresponded well with the predicted value of 91.81%. In addition, to investigate the transport properties of HEP and HEP-PLGA using a Caco-2 cell monolayer, and study the roles of the efflux transporters (P-gp) during the transport process. These results suggested that HEP can be absorbed more efficiently when encapsulated within the PLGA. These findings highlight the potential to the application of HEP in the formulation of functional foods. These results provide strategies in designing high absorbed polysaccharides with bioactive benefits.


Asunto(s)
Basidiomycota/química , Polisacáridos Fúngicos , Ácido Láctico , Nanopartículas/química , Ácido Poliglicólico , Células CACO-2 , Polisacáridos Fúngicos/química , Polisacáridos Fúngicos/farmacocinética , Polisacáridos Fúngicos/farmacología , Humanos , Ácido Láctico/química , Ácido Láctico/farmacocinética , Ácido Láctico/farmacología , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacocinética , Ácido Poliglicólico/farmacología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico
10.
Int J Nanomedicine ; 13: 569-583, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29416336

RESUMEN

BACKGROUND: Poly lactide (PLA) was proved in the last years to be good for use in sustained drug delivery and as carriers for vaccine antigens. In our previous research, pachyman (PHY)-encapsulated PLA (PHYP) nanospheres were synthesized and their function of controlling drug release was demonstrated. PURPOSE: In order to modify the fast drug-release rate of PHY when inoculated alone, the maturation of bone marrow dendritic cells (BMDCs) in vitro and their immunological enhancement in vivo were explored using PHYP nanospheres. METHODS: The maturation and antigen uptake of BMDCs were evaluated, both alone and with formulated antigen PHYP nanospheres, ie, ovalbumin (OVA)-loaded PHYP nanospheres, as an antigen delivery system, to investigate antigen-specific humoral and cellular immune responses. RESULTS: The results indicated that, when stimulated by PHYP, the BMDCs matured as a result of upregulated expression of co-stimulatory molecules; the mechanism was elucidated by tracing fluorescently labeled antigens in confocal laser scanning microscopy images and observing the uptake of nanospheres by transmission electron microscopy. It was further revealed that mice inoculated with OVA-PHYP had augmented antigen-specific IgG antibodies, increased cytokine secretion by splenocytes, increased splenocyte proliferation, and activation of cluster of differentiation (CD)4+ and CD8+ T cells in vivo. Elevated immune responses were produced by OVA-PHYP, possibly owing to the activation and maturation of dendritic cells (in draining lymph nodes). CONCLUSION: It was corroborated that PHY- and/or OVA-encapsulated PLA nanospheres elicited prominent antigen-presenting effects on BMDCs and heightened humoral and cellular immune responses compared with other formulations.


Asunto(s)
Diferenciación Celular , Células Dendríticas/citología , Células Dendríticas/inmunología , Glucanos/farmacología , Nanosferas/química , Ovalbúmina/inmunología , Poliésteres/química , Animales , Formación de Anticuerpos/efectos de los fármacos , Antígenos/inmunología , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Citocinas/metabolismo , Células Dendríticas/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Femenino , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/metabolismo , Masculino , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Nanosferas/ultraestructura , Tamaño de la Partícula , Electricidad Estática , Linfocitos T/citología , Vacunación
11.
J Control Release ; 118(1): 65-77, 2007 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-17250921

RESUMEN

Novel thermomechanical hydrogel scaffolds containing our previously prepared microspheres loaded with bone morphogenetic proteins (BMP) were successfully generated by radical crosslinking and low dose gamma-irradiation from combination of two kind of biomaterials: glycidyl methacrylated dextran (Dex-GMA) and gelatin. The structure of those resulting smart hybrid hydrogels was evaluated by mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) analyses, and as a function of the degree of Dex-GMA's substitution (DS), the proportion between Dex-GMA and gelatin, and the initial polyethyleneglycol (PEG) concentration used in the preparation of the hydrogels. The swelling and degradation properties and the temperature-sensitive drug release manner were determined by dynamic evaluation methods in vitro, and the gel content was also calculated. MIP analysis showed that by systematically altering the preparation parameters, the overall networks were clearly macroporous with pore sizes ranging from 5.6+/-4.2 to 37.7+/-13.7 microm. As expected, the pore size decreased as DS and initial PEG concentration increased, whereas the opposite was found for the gel content. Moreover, the porosity values ranged from 73.7+/-12.4% up to 89.6+/-6.3%. The SEM results also showed the inter-connective pores as well as microspheres encased into their porous structure of those hydrogels. The swelling and degradation properties of the resultant hydrogels varied according to the DS of Dex-GMA and initial PEG concentration, while the proportion between Dex-GMA and gelatin had no significant influence on those characterizations. By changing the composition ratio of the two precursors, the phase transition temperature (lower critical solution temperature, LSCT) of the hydrogel scaffolds could also be adjusted to be or near the body temperature, so BMP release from microsphere-hydrogel compounds could be accordingly controlled and the release period could be varied from 18 to more than 28 days. These results demonstrated that a novel temperature-sensitive and biodegradable Dex-GMA/gelatin scaffold containing microspheres loaded with BMP could be successfully developed from both dextran- and gelatin-based biomaterials, which could promisingly satisfy the need, desire, and expectation of both self-regulated drug delivery and tissue-engineering applications.


Asunto(s)
Proteínas Morfogenéticas Óseas/química , Dextranos/química , Compuestos Epoxi/química , Gelatina/química , Hidrogeles/química , Metacrilatos/química , Polietilenglicoles/química , Factor de Crecimiento Transformador beta/química , Materiales Biocompatibles/química , Proteína Morfogenética Ósea 2 , Proteínas Morfogenéticas Óseas/genética , Proteínas Morfogenéticas Óseas/farmacología , Sistemas de Liberación de Medicamentos , Gelatina/ultraestructura , Humanos , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Microesferas , Transición de Fase , Porosidad , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacología , Temperatura , Ingeniería de Tejidos , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/farmacología , Agua/química
12.
Drug Deliv ; 24(1): 1099-1111, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28776443

RESUMEN

Biocompatible and biodegradable poly(lactic-co-glycolic acid) (PLGA) has been approved by the US Food and Drug Administration and has frequently been used to develop potential vaccine delivery systems. The immunoregulation and immunopotentiation of Chinese yam polysaccharide (CYP) have been widely demonstrated. In the current study, cell uptake mechanisms in dendritic cells (DCs) were monitored in vitro using confocal laser scanning microscopy, transmission electron microscopy, and flow cytometry. To study a CYP-PLGA nanoparticle-adjuvanted delivery system, CYP and ovalbumin (OVA) were encapsulated in PLGA nanoparticles (CYPPs) to act as a vaccine, and the formulation was tested in immunized mice. The CYPPs more easily underwent uptake by DCs in vitro, and CYPP/OVA could stimulate more effective antigen-specific immune responses than any of the single-component formulations in vivo. Mice immunized using CYPP/OVA exhibited more secretion of OVA-specific IgG antibodies, better proliferation, and higher cytokine secretion by splenocytes and significant activation of CD3+CD4+ and CD3+CD8+ T cells. Overall, the CYPP/OVA formulation produced a stronger humoral and cellular immune response and a mixed Th1/Th2 immune response with a greater Th1 bias in comparison with the other formulations. In conclusion, the data demonstrate that the CYPP-adjuvanted delivery system has the potential to strengthen immune responses and lay the foundation for novel adjuvant design.


Asunto(s)
Nanopartículas , Animales , Linfocitos T CD8-positivos , Dioscorea , Glicoles , Ácido Láctico , Ratones , Ovalbúmina , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polisacáridos , Vacunas
13.
Chin Med J (Engl) ; 130(4): 477-486, 2017 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-28218223

RESUMEN

BACKGROUND: Regenerative techniques help promote the formation of new attachment and bone filling in periodontal defects. However, the dimensions of intraosseous defects are a key determinant of periodontal regeneration outcomes. In this study, we evaluated the efficacy of use of anorganic bovine bone (ABB) graft in combination with collagen membrane (CM), to facilitate healing of noncontained (1-wall) and contained (3-wall) critical size periodontal defects. METHODS: The study began on March 2013, and was completed on May 2014. One-wall (7 mm × 4 mm) and 3-wall (5 mm × 4 mm) intrabony periodontal defects were surgically created bilaterally in the mandibular third premolars and first molars in eight beagles. The defects were treated with ABB in combination with CM (ABB + CM group) or open flap debridement (OFD group). The animals were euthanized at 8-week postsurgery for histological analysis. Two independent Student's t-tests (1-wall [ABB + CM] vs. 1-wall [OFD] and 3-wall [ABB + CM] vs. 3-wall [OFD]) were used to assess between-group differences. RESULTS: The mean new bone height in both 1- and 3-wall intrabony defects in the ABB + CM group was significantly greater than that in the OFD group (1-wall: 4.99 ± 0.70 mm vs. 3.01 ± 0.37 mm, P < 0.05; 3-wall: 3.11 ± 0.59 mm vs. 2.08 ± 0.24 mm, P < 0.05). The mean new cementum in 1-wall intrabony defects in the ABB + CM group was significantly greater than that in their counterparts in the OFD group (5.08 ± 0.68 mm vs. 1.16 ± 0.38 mm; P < 0.05). Likewise, only the 1-wall intrabony defect model showed a significant difference with respect to junctional epithelium between ABB + CM and OFD groups (0.67 ± 0.23 mm vs. 1.12 ± 0.28 mm, P < 0.05). CONCLUSIONS: One-wall intrabony defects treated with ABB and CM did not show less periodontal regeneration than that in 3-wall intrabony defect. The noncontained 1-wall intrabony defect might be a more discriminative defect model for further research into periodontal regeneration.


Asunto(s)
Regeneración Ósea/fisiología , Regeneración Tisular Guiada Periodontal/métodos , Cicatrización de Heridas/fisiología , Pérdida de Hueso Alveolar/cirugía , Animales , Materiales Biocompatibles/uso terapéutico , Sustitutos de Huesos/uso terapéutico , Bovinos , Perros , Masculino
14.
J Control Release ; 114(2): 209-22, 2006 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-16859799

RESUMEN

The present work focused on the design of novel hydrogel microspheres based on both dextran- and gelatin-derived biomaterials, and discussed whether locally controlled delivery of IGF-I from dextran-co-gelatin hydrogel microspheres (DG-MP) was useful for periodontal regeneration enhancement. Microspheres were synthesized when gelatin was cooperating with glycidyl methacrylate (GMA) derivatized dextrans (Dex-GMA) and the resultant DG-MP with a hydrogel character of which the cross-linking density could be controlled by the degree of substitution (DS, the number of methacrylates per 100 glucopyranose residues) of Dex-GMA. In this study, three types of DG-MP (DG-MP4.7, DG-MP6.3 and DG-MP7.8) obtained from gelatin and Dex-GMA (differing in DS: 4.7, 6.3 and 7.8 respectively) were prepared and characterized by swelling and degradation properties, drug release kinetics and biological capability in promoting tissue regeneration. By swelling in aqueous positively charged IGF-I solutions, the protein could be encapsulated in DG-MP by polyionic complexation with negatively charged acidic gelatin. No obvious influence of Dex-GMA's DS on DG-MP's configuration and size was observed, and the release and degraded properties showed no significant difference between three types of DG-MP in PBS buffer either. However, high DS of Dex-GMA could lower microsphere's swelling, prolong its degraded time and minimize IGF-I burst release markedly in dextranase-containing PBS, where IGF-I release from a slow release type of microspheres (DG-MP7.8) could be maintained more than 28 days, and an effective protein release kinetics without a significant burst but a relevantly constant release after the initial burst was achieved. IGF-I in DG-MP resulted in more new bone formation in the periodontal defects within 4 or 8 weeks than IGF-I in blood clot directly did (P < 0.01). The observed newly formation of periodontal tissues including the height and percentage of new bone and new cementum on the denuded root surfaces of the furcation area in DG-MP7.8 group were more than that in other groups (P < 0.05). The adequate width of regenerative periodontal ligament (PDL), regular Sharpey's fibers and alveolar bone reconstruction could be observed only in DG-MP7.8 group. These combined results demonstrate that effective release kinetics can be realized by adjusting the DS of Dex-GMA and followed cross-linking density of DG-MP, and that locally controlled delivery of IGF-I from slow release type of DG-MP may serve as a novel therapeutic strategy for periodontal tissue regeneration.


Asunto(s)
Encía/efectos de los fármacos , Encía/crecimiento & desarrollo , Factor I del Crecimiento Similar a la Insulina/administración & dosificación , Regeneración/efectos de los fármacos , Animales , Regeneración Ósea/efectos de los fármacos , Cristalografía por Rayos X , Dextranasa/química , Dextranos , Perros , Sistemas de Liberación de Medicamentos , Excipientes , Defectos de Furcación/tratamiento farmacológico , Defectos de Furcación/patología , Gelatina , Encía/patología , Humanos , Factor I del Crecimiento Similar a la Insulina/farmacocinética , Focalización Isoeléctrica , Masculino , Microesferas , Proteínas Recombinantes/farmacología
15.
Int J Pharm ; 307(1): 23-32, 2006 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-16260104

RESUMEN

Recent developments of biotechnology have produced a great variety of protein and bioactive drugs. For these drugs to be used therapeutically, suitable drug delivery systems have become increasingly essential. Dextran-derived biomaterials have been considered to be compatible matrices for protein and bioactive drugs because of their hydrophilic properties and ability to control drug dissolution and permeability. A novel class of dextran-glycidylmethacrylate (Dex-GMA)/poly(ethylene glycol) (PEG) microspheres were designed and synthesized by polymerization of Dex-GMA emulsified in an aqueous PEG solution. Dex-GMA was prepared by substituting the hydroxyl groups in Dex by GMA. The drug loading and in vitro drug release was evaluated by routine procedure and the biological activity of BMP-loaded microspheres was studied by experimental cytology methods. Recombinant human bone morphogenetic protein-2 (rhBMP-2) were entrapped in dextran-derived microspheres quantitatively and with full preservation of their biological activity. In vitro release kinetics indicated that dextran-derived microspheres could retain rhBMP-2 in a variable manner depending on the preparation and degradation of the microspheres. The release profiles of rhBMP-2 from microspheres as a function of time showed that rhBMP-2 releasing kinetics in vitro fitted to first-order and Higuchi equations. The release profile in vitro was in accord with two phases kinetics law and more than 60% drug were released during 20 days. Cytology studies showed rhBMP-2 microspheres have good biological effects on cultured periodontal ligament cells, and could achieve a longer action time than concentration of rhBMP-2 solution. These properties make those microspheres interesting osteo-conductive BMP carriers, allowing to decrease the amount of implanted factor required for tissue regeneration.


Asunto(s)
Proteínas Morfogenéticas Óseas/química , Dextranos/química , Portadores de Fármacos , Microesferas , Proteínas Recombinantes/química , Factor de Crecimiento Transformador beta/química , Fosfatasa Alcalina/metabolismo , Proteína Morfogenética Ósea 2 , Proteínas Morfogenéticas Óseas/farmacología , Regeneración Ósea , Células Cultivadas , Composición de Medicamentos , Compuestos Epoxi/química , Humanos , Metacrilatos/química , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteopontina , Ligamento Periodontal/efectos de los fármacos , Ligamento Periodontal/metabolismo , Polietilenglicoles/química , Proteínas Recombinantes/farmacología , Sialoglicoproteínas/metabolismo , Factor de Crecimiento Transformador beta/farmacología
16.
ACS Biomater Sci Eng ; 2(5): 734-740, 2016 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-33440570

RESUMEN

Sealing exposed dental tubules is the most effective and long-term way to relieve the pain induced by dental sensitivity. A bioactive hollow sphere (strontium substituted calcium phosphate) was synthesized and added in toothpaste to study its effect on dental hypersensitivity via tooth tubules occlusion and mineralization. The size of spheres is perfect for penetrating into dental tubules, reaching to 20 µm into the tubules. The exposed dental tubules were occluded by spheres and new apatite layer after 3 days brushing. The spheres attached to the surface of dentin and the mineralized surface contained two layers, a porous layer followed by a dense apatite layer. The porous layer can be dissolved in an acidic solution, but the following dense layer could be kept even after soaking in an acid solution. In conclusion, Sr-substituted calcium phosphate spheres could be a good candidate for at-home treatment of dental hypersensitivity.

17.
Dent J (Basel) ; 5(1)2016 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-29563409

RESUMEN

The objective of this study was to investigate if a prolonged bleaching effect of carbamide peroxide-loaded hollow calcium phosphate spheres (HCPS) can be achieved. HCPS was synthesized via a hydrothermal reaction method. Carbamide peroxide (CP) was-loaded into HCPS by mixing with distilled water as solvent. We developed two bleaching gels containing CP-loaded HCPS: one gel with low HP concentration as at-home bleaching gel, and one with high HP concentration as in-office gel. Their bleaching effects on stained human permanent posterior teeth were investigated by measuring the color difference before and after bleaching. The effect of gels on rhodamine B degradation was also studied. To investigate the potential effect of remineralization of using HCPS, bleached teeth were soaked in phosphate buffer solution (PBS) containing calcium and magnesium ions. Both bleaching gels had a prolonged whitening effect, and showed a strong ability to degrade rhodamine B. After soaking in PBS for 3 days, remineralization was observed at the sites where HCPS attached to the teeth surface. CP-loaded HCPS could prolong the HP release behavior and improve the bleaching effect. HCPS was effective in increasing the whitening effect of carbamide peroxide and improving remineralization after bleaching process.

18.
Int J Pharm ; 511(1): 140-150, 2016 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-27374200

RESUMEN

This paper first provides that Chinese yam polysaccharide (CYP) is encapsulated by PLGA using a double emulsion solvent evaporation method and aims to screen the optimal preparation of CYP-PLGA nanoparticles (CYPP) using response surface methodology (RSM). The volume ratio of the internal water phase to the organic phase (W1:O), the volume ratio of the primary emulsion to the external water phase (PE:W2) and the concentration of Poloxamer 188 (F68) are deemed key variables for the encapsulation efficiency of CYPP. The results demonstrated that the data were accurately fitted into the RSM model. According to the RSM, the optimal scheme was a volume ratio of W1:O of 1:9, a volume ratio of PE: W2 of 1:10 and a concentration of F68 (W/V) of 0.7%. TEM and SEM images demonstrated that the nanoparticles had a spherical shape and smooth surface. The CYP and CYPP in vitro release studies demonstrated that the CYPP showed a release rate 53.41% lower than the release rate of CYP after 48h. The result of pro-proliferation and flow cytometry emerged that the CYPP were more effective compared with the free CYP and blank PLGA nanoparticles in promoting lymphocyte proliferation and triggering the transformation of T lymphocytes into Th cells.


Asunto(s)
Dioscorea , Ácido Láctico/farmacología , Nanopartículas/administración & dosificación , Extractos Vegetales/farmacología , Ácido Poliglicólico/farmacología , Polisacáridos/farmacología , Linfocitos T/inmunología , Animales , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Relación Dosis-Respuesta a Droga , Ácido Láctico/síntesis química , Masculino , Ratones , Ratones Endogámicos BALB C , Nanopartículas/química , Ácido Poliglicólico/síntesis química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polisacáridos/síntesis química , Linfocitos T/efectos de los fármacos
19.
Int J Nanomedicine ; 11: 6795-6808, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28008254

RESUMEN

Nanomedicine, the medical application of nanotechnology, promises a seemingly limitless range of applications from drug delivery to adjuvants and therapeutics. Our current research is focused on natural polymer-based liposome adjuvants. With the aim of inducing protective and long-lasting immunity, the immunological adjuvant activity of Rehmannia glutinosa polysaccharide liposome (RGPL) was investigated. In vivo, the splenic lymphocyte proliferation ratios and ovalbumin-specific immunoglobulin G titers of ovalbumin-RGPL-vaccinated mice were significantly upregulated. In draining lymph nodes, the expression of MHC II+CD11c+ and CD86+CD11c+ was increased by RGPL; in addition, the percentages of central memory cells (TCM) and effector memory cells (TEM) were also elevated. RGPL could effectively provide adequate antigen exposure in lymph nodes. In vitro, RGPL could promote dendritic cell maturation and enhance dendritic cell functions, such as the mixed lymphocyte reaction and antigen presentation. Overall, the results demonstrated that RGPL has the potential to act as an effective controlled release vaccine adjuvant.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Presentación de Antígeno/efectos de los fármacos , Células Dendríticas/inmunología , Liposomas/farmacología , Polisacáridos/farmacología , Rehmannia/química , Animales , Antígeno B7-2/química , Antígeno CD11c/química , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Citocinas/química , Células Dendríticas/efectos de los fármacos , Femenino , Inmunoglobulina G/química , Inmunohistoquímica , Memoria Inmunológica , Ganglios Linfáticos/efectos de los fármacos , Linfocitos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ovalbúmina/inmunología , Bazo/efectos de los fármacos , Linfocitos T/citología
20.
Clin Vaccine Immunol ; 22(4): 421-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25673304

RESUMEN

Influenza whole inactivated virus (WIV) is more immunogenic and induces protective antibody responses compared with other formulations, like split virus or subunit vaccines, after intranasal mucosal delivery. Polyethyleneimine (PEI), an organic polycation, is widely used as a reagent for gene transfection and DNA vaccine delivery. Although PEI recently has demonstrated potent mucosal adjuvant activity for viral subunit glycoprotein antigens, its immune activity with H9N2 WIV is not well demonstrated. Here, mice were immunized intranasally with H9N2 WIV combined with PEI, and the levels of local respiratory tract and systemic immune responses were measured. Compared to H9N2 WIV alone, antigen-specific IgA levels in the local nasal cavity, trachea, and lung, as well as levels of IgG and its subtypes (IgG1 and IgG2a) in the serum, were strongly enhanced with the combination. Similarly, the activation and proliferation of splenocytes were markedly increased. In addition, PEI is superior as an H9N2 WIV delivery system due to its ability to greatly increase the viral adhesion to mucosal epithelial cells and to enhance the cellular uptake and endosomal escape of antigens in dendritic cells (DCs) and further significantly activate DCs to mature. Taken together, these results provided more insights that PEI has potential as an adjuvant for H9N2 particle antigen intranasal vaccination.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Subtipo H9N2 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la Influenza/inmunología , Polietileneimina/administración & dosificación , Vacunación/métodos , Administración Intranasal , Animales , Anticuerpos Antivirales/análisis , Anticuerpos Antivirales/sangre , Inmunidad Mucosa , Inmunoglobulina A/análisis , Inmunoglobulina G/sangre , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Sistema Respiratorio/inmunología , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/inmunología
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