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1.
BMC Musculoskelet Disord ; 24(1): 253, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37005598

RESUMEN

OBJECTIVE: Unilateral posterior scissors-bite (uPSB) malocclusion is common clinically. This study aimed to investigate the condylar morphological alterations and condyle-fossa relationship in patients with uPSB, through cone beam computed tomography (CBCT) and three-dimensional reconstructive imaging technique. METHODS: A retrospective study was designed to comparatively analyze 95 patients with uPSB between July 2016 and December 2021. They were divided into three subgroups: 12 to 20, 21 to 30, and ≥ 31 years, according the age distribution. The morphological parameters regarding condyle, fossa, and joint space after three-dimensional reconstruction were measured and analyzed by a series of digital software. SPSS 26.0 software package was performed for statistical analysis on data sets, using paired t-test, one-way analysis of variance, Wilcoxon signed-rank sun test, Kruskal-Wallis H test, and Bonferroni correction. RESULTS: The condylar volume (CV) of scissors-bite side was greater than that of the non-scissors-bite side (CV A = 1740.68 ± 559.80 mm3 > CV N = 1662.25 ± 524.88 mm3, P = 0.027). So was the condylar superficial area (CSA) (CSA A = 818.71 ± 186.82 mm2 > CSA N = 792.63 ± 173.44 mm2, P = 0.030), and the superior joint space (SJS) [SJS A = 2.46 (1.61, 3.68) mm) > SJS N = 2.01 (1.55, 2.87) mm), P = 0.018], and the anterior joint space (AJS) (AJS A = 3.94 ± 1.46 mm > AJS N = 3.57 ± 1.30 mm, P = 0.017). The constituent ratios of the different parts of the bilateral condyles were 23% on the posterior slope, 21% on the top, 20% on the anterior slope, 19% on the lateral slope and 17% on the medial slope, respectively. CONCLUSION: Due to long-term abnormal occlusion of uPSB, the pathological bite force in temporomandibular joint would cause changes in the shape of the condyle. Among them, CV, CSA, SJS and AJS had significant changes in the scissors-bite status, which has the greatest damage to the posterior slope of the condyloid process.


Asunto(s)
Maloclusión , Cóndilo Mandibular , Humanos , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/cirugía , Cóndilo Mandibular/patología , Imagenología Tridimensional , Estudios Retrospectivos , Proyectos Piloto , Maloclusión/diagnóstico por imagen , Maloclusión/cirugía , Maloclusión/patología
2.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36675089

RESUMEN

Active packaging materials protect food from deterioration and extend its shelf life. In the quest to design intriguing packaging materials, biocomposite ZnO/plant polyphenols/cellulose/polyvinyl alcohol (ZnPCP) was prepared via simple hydrothermal and casting methods. The structure and morphology of the composite were fully analyzed using XRD, FTIR, SEM and XPS. The ZnO particles, plant polyphenols (PPL) and cellulose were found to be dispersed in PVA. All of these components share their unique functions with the composite's properties. This study shows that PPL in the composite not only improves the ZnO dispersivity in PVA as a crosslinker, but also enhances the water barrier of PVA. The ZnO, PPL and cellulose work together, enabling the biocomposite to perform as a good food packaging material with only a 1% dosage of the three components in PVA. The light shielding investigation showed that ZnPCP-10 can block almost 100% of both UV and visible light. The antibacterial activities were evaluated by Gram-negative Escherichia coli (E. coli) and Gram-positive staphylococcus aureus (S. aureus), with 4.4 and 6.3 mm inhibition zones, respectively, being achieved by ZnPCP-10. The enhanced performance and easy degradation enables the biocomposite ZnPCP to be a prospect material in the packaging industry.


Asunto(s)
Quitosano , Óxido de Zinc , Embalaje de Alimentos , Alcohol Polivinílico/química , Celulosa/química , Óxido de Zinc/química , Quitosano/química , Staphylococcus aureus , Escherichia coli , Antibacterianos/farmacología , Antibacterianos/química
3.
Nano Lett ; 21(24): 10279-10283, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34851648

RESUMEN

Because of the extraordinary properties including high atomic numbers and large µτ products, metal halide perovskites have been widely employed and used for radiation detecting. Cs4PbI6 material has a high X-ray attenuation coefficient and excellent electrical properties that have a good potential in X-ray detection applications. Here, we have designed a flexible polymer-encapsulated Au/Cs4PbI6/Au X-ray detector with outstanding sensitivity of 256.20 µC Gy-1 cm-2 irradiated by 30 keV X-ray at 10 V bias, long-time stability, and durable flexibility without obvious degradation after bending for 600 cycles. These features demonstrate that this polymer-encapsulated durable flexible and sensitive X-ray detector could open a new possibility for next-generation radiation applications in dosimeter, imaging technologies.


Asunto(s)
Metales , Polímeros , Radiografía , Rayos X
4.
J Am Chem Soc ; 142(6): 2709-2714, 2020 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-31999447

RESUMEN

Metal complexes that exhibit both near-infrared (NIR) phosphorescence imaging and chemotherapeutic activity would represent a novel class of anticancer drugs in clinical tumor treatment. In this work, a series of novel rodlike nanomicelles have been fabricated in water by coupling poly(ethylene oxide)-block-poly(sodium acrylate) and [Rh(C≡N-2,6-xylyl)4]+(1/2SO4)-. These nanomicelles exhibit intense NIR phosphorescence and excellent stability. As revealed by in vivo NIR phosphorescence imaging data, the rodlike nanomicelle can selectively stain tumor sites with a long retention time. Moreover, the nanorods demonstrate effective anticancer activity by precisely killing tumor tissues without damaging healthy organs in vivo. To the best of our knowledge, this research provides the first example of metal-based complexes showing simultaneous NIR luminescence imaging and antitumor activity in vivo.


Asunto(s)
Antineoplásicos/farmacología , Complejos de Coordinación/farmacología , Micelas , Nanoestructuras , Polímeros/química , Rodio/química , Espectroscopía Infrarroja Corta/métodos , Animales , Luminiscencia , Ratones , Ratones Desnudos , Agua/química , Ensayos Antitumor por Modelo de Xenoinjerto
5.
ACS Sens ; 6(4): 1643-1648, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-33761245

RESUMEN

X-ray dosimeters are of significance for detecting the levels of ionizing radiation exposure in cells and phantoms; thus, they can further optimize X-ray radiotherapy in the clinic. In this paper, we designed a polyacrylamide-based nanogel sensor that is capable of measuring X-ray doses. The dosimeters were prepared by anchoring an X-ray-responsive probe (aminophenyl fluorescein, APF) to poly(acrylamide-co-N-(3-aminopropyl) methyl acrylamide) nanogels. The premise behind the dose measurement is the transition of APF to fluorescence in the presence of hydroxyl radicals that are caused by the radiolysis of water molecules under X-rays. Therefore, the dose of X-rays can be readily detected by measuring the fluorescence intensity of the resultant nanogel immediately after irradiation using fluorescence spectroscopy principles. Using an RS2000 X-ray biological irradiator, our dosimeters showed good linearity responsivity at X-ray doses ranging from 0 to 15 Gy, with a limit of detection (LOD) of 0.5 Gy. Additionally, the signals showed temperature stability (25-65 °C), durability (5 weeks), and dose-rate (1.177 and 6 Gy/min) and energy independence (160 kVp and 6 MV). As a proof-of-concept, we used our sensors to fluorescently detect X-ray doses in A549 tumor cells and 3D-printed eye phantoms. The results showed that our dosimeters were able to accurately predict doses similar to those used by treatment plan systems.


Asunto(s)
Dosímetros de Radiación , Radiometría , Nanogeles , Polietilenglicoles , Polietileneimina , Rayos X
6.
Int J Biol Macromol ; 191: 584-590, 2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34582905

RESUMEN

The specification of the local structure and clarification of interfacial interactions of biomass composites is of tremendous significance in synthesizing novel materials and advancing their performance in various demanding applications. However, it remains challenging due to the limitations of experimental techniques, particularly for the manner that biomass composites commonly have hydrogen bonds involved in the vicinity of active sites and interfaces. Herein, the cellulose/Mg(OH)2 nanocomposite has been synthesized via a simple hydrothermal approach and examined by density functional theory (DFT) calculations. The composite exhibits a layered morphology; Mg(OH)2 flakes are around 50 nm in size and well-dispersed. They either anchor onto the cellulose surface or intercalate between layers. The specific composite structure was confirmed theoretically, in line with XRD, SEM and TEM observations. The interfacial interactions were found to be hydrogen bonding. The average adsorption energy per hydroxyl group was computed to be within -0.47 and -0.26 eV for a composite model comprising three cellulose chains and a two-layered Mg(OH)2 cluster. The combined computational/experimental results allow to postulate the antibacterial mechanism of the nanocomposite.


Asunto(s)
Antibacterianos/química , Celulosa/análogos & derivados , Hidróxido de Magnesio/química , Nanocompuestos/química , Adsorción , Antibacterianos/farmacología , Biomasa , Enlace de Hidrógeno , Termodinámica
7.
Adv Healthc Mater ; 9(7): e1901773, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32125787

RESUMEN

The inadequacy of conventional cell-monolayer planar cultures and animal experiments in predicting the toxicity and clinical efficacy of drug candidates has led to an imminent need for in vitro methods with the ability to better represent in vivo conditions and facilitate the systematic investigation of drug candidates. Recent advances in 3D bioprinting have prompted the precise manipulation of cells and biomaterials, rendering it a promising technology for the construction of in vitro tissue/organ models and drug screening devices. This review presents state-of-the-art in vitro methods used for preclinical drug screening and discusses the limitations of these methods. In particular, the significance of constructing 3D in vitro tissue/organ models and microfluidic analysis devices for drug screening is emphasized, and a focus is placed on the grafting process of 3D bioprinting technology to the construction of such models and devices. The in vitro methods for drug screening are generalized into three types: mini-tissue, organ-on-a-chip, and tissue/organ construct. The revolutionary process of the in vitro methods is demonstrated in detail, and relevant studies are listed as examples. Specifically, the tumor model is adopted as a precedent to illustrate the possible grafting of 3D bioprinting to antitumor drug screening.


Asunto(s)
Bioimpresión , Animales , Materiales Biocompatibles , Evaluación Preclínica de Medicamentos , Dispositivos Laboratorio en un Chip , Impresión Tridimensional , Ingeniería de Tejidos
8.
Clin Cancer Res ; 26(17): 4521-4530, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32499235

RESUMEN

PURPOSE: Patients with relapsed/refractory primary mediastinal B-cell lymphoma (rrPMBCL) represent a particularly challenging population to treat, with few life-saving treatment options in the context of a dismal prognosis. PATIENTS AND METHODS: In this open-label, single-arm, phase II study, the safety and efficacy of combined regimen of chemotherapy consisting of gemcitabine, vinorelbine, and pegylated liposomal doxorubicin (GVD) plus anti-PD-1 antibody camrelizumab was assessed in rrPMBCL. Patients received chemo-immunotherapy every 3 weeks until the second confirmed complete response (CR) or up to 12 cycles, followed by camrelizumab monotherapy for up to 1 year. The primary endpoints were objective response rate (ORR) and safety. RESULTS: Twenty-seven response evaluable patients were enrolled, who received a median of three first-line therapies, 59% with bulky disease. The ORR was 74%, including 56% with a CR. A median time of 1.7 months to response was observed, with 78% exhibiting tumor shrinkage at the first evaluation. After 24.8 months median follow-up, the median duration of response was not reached, with a 65% 2-year estimated response rate. Thirteen responders remained in sustained complete remission. Estimated 24-month progression-free survival and overall survival rates were 48.2% and 81.5%, respectively. Any grade and grade 3 treatment-related adverse events (AE) occurred in 93% and 33% of patients, respectively; with no grade 4 or 5 AEs. Baseline levels of IL10, IFNγ, and soluble Fas were associated with objective response. CONCLUSIONS: Camrelizumab plus GVD chemotherapy offers a potent option as life-saving chemo-immunotherapy with promising efficacy and a manageable safety profile for patients with rrPMBCL, especially with bulky aggressive disease.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Linfoma de Células B/tratamiento farmacológico , Neoplasias del Mediastino/tratamiento farmacológico , Adolescente , Adulto , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Biomarcadores de Tumor/sangre , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Doxorrubicina/análogos & derivados , Resistencia a Antineoplásicos , Femenino , Humanos , Interferón gamma/sangre , Interleucina-10/sangre , Linfoma de Células B/sangre , Linfoma de Células B/mortalidad , Linfoma de Células B/patología , Masculino , Neoplasias del Mediastino/sangre , Neoplasias del Mediastino/mortalidad , Neoplasias del Mediastino/patología , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Polietilenglicoles/administración & dosificación , Polietilenglicoles/efectos adversos , Pronóstico , Supervivencia sin Progresión , Vinorelbina/administración & dosificación , Vinorelbina/efectos adversos , Adulto Joven , Receptor fas/sangre
9.
Mater Sci Eng C Mater Biol Appl ; 112: 110896, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32409053

RESUMEN

Cell therapy is a promising strategy in which living cells or cellular materials are delivered to treat a variety of diseases. Here, we developed an electrospray bioprinting method to rapidly generate cell-laden hydrogel microspheres, which limit the migration of the captured cells and provide an immunologically privileged microenvironment for cell survival in vivo. Currently, therapeutic angiogenesis aims to induce collateral vessel formation after limb ischemia. However, the clinical application of gene and cell therapy has been impeded by concerns regarding its inefficacy, as well as the associated risk of immunogenicity and oncogenicity. In this study, hydrogel microspheres encapsulating VEGF-overexpressing HEK293T cells showed good safety via subcutaneously injecting into male C57BL/6 mice. In addition, these cell-modified microspheres effectively promoted angiogenesis in a mouse hind-limb ischemia model. Therefore, we demonstrated the great therapeutic potential of this approach to induce angiogenesis in limb ischemia, indicating that bioprinting has a bright future in cell therapy.


Asunto(s)
Materiales Biocompatibles/química , Microesferas , Neovascularización Fisiológica/fisiología , Alginatos/química , Animales , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/uso terapéutico , Bioimpresión , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Células HEK293 , Miembro Posterior/patología , Células Endoteliales de la Vena Umbilical Humana , Humanos , Hidrogeles/química , Isquemia/terapia , Masculino , Ratones , Ratones Endogámicos C57BL , Neovascularización Fisiológica/efectos de los fármacos , Andamios del Tejido/química , Factor A de Crecimiento Endotelial Vascular/metabolismo
10.
J Vis Exp ; (154)2019 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-31904016

RESUMEN

Gelatin methacryloyl (GelMA) has become a popular biomaterial in the field of bioprinting. The derivation of this material is gelatin, which is hydrolyzed from mammal collagen. Thus, the arginine-glycine-aspartic acid (RGD) sequences and target motifs of matrix metalloproteinase (MMP) remain on the molecular chains, which help achieve cell attachment and degradation. Furthermore, formation properties of GelMA are versatile. The methacrylamide groups allow a material to become rapidly crosslinked under light irradiation in the presence of a photoinitiator. Therefore, it makes great sense to establish suitable methods for synthesizing three-dimensional (3D) structures with this promising material. However, its low viscosity restricts GelMA's printability. Presented here are methods to carry out 3D bioprinting of GelMA hydrogels, namely the fabrication of GelMA microspheres, GelMA fibers, GelMA complex structures, and GelMA-based microfluidic chips. The resulting structures and biocompatibility of the materials as well as the printing methods are discussed. It is believed that this protocol may serve as a bridge between previously applied biomaterials and GelMA as well as contribute to the establishment of GelMA-based 3D architectures for biomedical applications.


Asunto(s)
Bioimpresión/métodos , Gelatina/química , Hidrogeles/química , Metacrilatos/química , Impresión Tridimensional , Animales , Materiales Biocompatibles/química , Colágeno , Microfluídica , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Viscosidad
11.
Nat Commun ; 10(1): 3184, 2019 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-31320641

RESUMEN

Thoracic aortic dissection (TAD) is an aggressive vascular disease that requires early diagnosis and effective treatment. However, due to the particular vascular structure and narrowness of lesion location, there are no effective drug delivery systems for the therapy of TAD. Here, we report a multifunctional delivery nanosystem (TP-Gd/miRNA-ColIV) composed of gadolinium-chelated tannic acid (TA), low-toxic cationic PGEA (ethanolamine-aminated poly(glycidyl methacrylate)) and type IV collagen targeted peptide (ColIV) for targeted nucleic acid therapy, early diagnosis and noninvasive monitoring of TAD. Such targeted therapy with miR-145 exhibits impressive performances in stabilizing the vascular structures and preventing the deterioration of TAD. After the treatment with TP-Gd/miR-145-ColIV, nearly no dissection occurs in the thoracic aortic arches of the mice with TAD model. Moreover, TP-Gd/miRNA-ColIV also demonstrates good magnetic resonance imaging (MRI) ability and can be used to noninvasively monitor the development conditions of TAD.


Asunto(s)
Aneurisma de la Aorta Torácica/terapia , Disección Aórtica/terapia , Sistemas de Liberación de Medicamentos/métodos , Terapia Genética/métodos , MicroARNs/administración & dosificación , MicroARNs/uso terapéutico , Disección Aórtica/patología , Animales , Aneurisma de la Aorta Torácica/patología , Células Cultivadas , Colágeno Tipo IV/química , Gadolinio/química , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , Ácidos Polimetacrílicos/química , Taninos/química , Arterias Torácicas/patología
12.
Adv Mater ; 30(31): e1801570, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29920798

RESUMEN

Nucleic acid (NA)-based therapy is proposed to address serious diseases such as cardiovascular diseases (CVDs). Powerful NA delivery vehicles are essential for effective gene therapy. Herein, a novel type of delivery vehicle, an unlockable core-shell nanocomplex (Hep@PGEA) with self-accelerating NA release, is structurally designed. Hep@PGEA is composed of disulfide-bridged heparin nanoparticle (HepNP) core and low-toxicity PGEA cationic shell. In comparison with NA, heparin, a negatively charged polysaccharide macromolecule, exhibits stronger interactions with cationic species. Upon the breakdown of redox-responsive HepNP cores, unlocked heparin would interact with the outer cationic shells and replace the condensed NA to facilitate NA release. Such unique Hep@PGEA is successfully explored for effective miRNA-pDNA staged gene therapy of myocardial infarction (MI), one of the most serious CVDs. With the progression of MI, glutathione amounts in heart tissues increase. MiR-499 (for the inhibition of cardiomyocyte apoptosis) and plasmid encoding vascular endothelial growth factor (for the promotion of angiogenesis) are sequentially delivered for systemic treatment of MI. Such treatment produces impressive results in restoring heart function and suppressing cardiac hypertrophy. Due to the wide existence of redox agents in cells, the proposed unlockable delivery nanovehicle and staged therapy strategy can provide new methods to effectively treat different serious diseases.


Asunto(s)
ADN/metabolismo , Terapia Genética , MicroARNs/metabolismo , Infarto del Miocardio/terapia , Nanopartículas/química , Animales , Carbocianinas/química , ADN/química , Glutatión/química , Heparina/química , Ratones , MicroARNs/química , Microscopía de Fuerza Atómica , Microscopía Confocal , Infarto del Miocardio/patología , Tamaño de la Partícula , Ácidos Polimetacrílicos/química , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
13.
ACS Appl Mater Interfaces ; 8(13): 8376-85, 2016 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-26947134

RESUMEN

Polysaccharide-based copolymers have attracted much attention due to their effective performances. Heparin, as a kind of polysaccharide with high negative charge densities, has attracted much attention in biomedical fields. In this work, we report a flexible way to adjust the solubility of heparin from water to oil via the introduction of tetrabutylammonium groups for further functionalization. A range of heparin-based comb copolymers with poly(poly(ethylene glycol) methyl ether methacrylate) (PPEGMEMA), poly(dimethylaminoethyl methacrylate) (PDMAEMA), or PPEGMEMA-b-PDMAEMA side chains were readily synthesized in a MeOH/dimethylsulfoxide mixture via atom-transfer radical polymerization. The heparin-based polymer nanoparticles involving cationic PDMAEMA were produced due to the electrostatic interaction between the negatively charged heparin backbone and PDMAEMA grafts. Then the pDNA condensation ability, cytotoxicity, and gene transfection efficiency of the nanoparticles were characterized in comparison with the reported gene vectors. The nanoparticles were proved to be effective gene vectors with low cytotoxicity and high transfection efficiency. This study demonstrates that by adjusting the solubility of heparin, polymer graft functionalization of heparin can be readily realized for wider applications.


Asunto(s)
Técnicas de Transferencia de Gen , Heparina/química , Nanopartículas/administración & dosificación , Transfección/métodos , Vectores Genéticos/efectos adversos , Heparina/efectos adversos , Heparina/farmacología , Humanos , Metacrilatos/efectos adversos , Metacrilatos/química , Metacrilatos/farmacología , Nanopartículas/efectos adversos , Nanopartículas/química , Nylons/química , Nylons/farmacología , Polietilenglicoles/efectos adversos , Polietilenglicoles/química , Polietilenglicoles/farmacología , Polímeros/efectos adversos , Polímeros/química , Solubilidad
14.
Artículo en Inglés | MEDLINE | ID: mdl-16203184

RESUMEN

A poly (methacrylic acid-ethylene glycol dimethacrylate, MAA-EGDMA) monolithic capillary was used for the in-tube solid-phase microextraction (in-tube SPME) of several angiotensin II receptor antagonists (ARA-IIs) from human plasma and urine. Under the optimized extraction condition, the protein component of the biological sample was flushed through the monolithic capillary, while the analytes were successfully trapped. Coupled to HPLC with fluorescence detection, this on-line in-tube SPME method was successfully applied for the determination of candesartan, losartan, irbesartan, valsartan, telmisartan, and their detection limits were found to be 0.1-15.3ng/mL and 0.1-15.2ng/mL in human plasma and urine, respectively. The method was linear over the range of 0.5-200ng/mL for telmisartan, 5-2000ng/mL for candesartan and irbesartan, 10-2000ng/mL for valsartan, and 50-5000ng/mL for losartan with correlation coefficients being above 0.9985 in plasma sample and above 0.9994 in urine sample. The method reproducibility was evaluated at three concentration levels, resulting in the R.S.D. <7%. The poly (MAA-EGDMA) monolithic capillary was demonstrated to be robust and biocompatible by using direct injections of biological samples.


Asunto(s)
Antagonistas de Receptores de Angiotensina , Materiales Biocompatibles/química , Cromatografía Líquida de Alta Presión/métodos , Humanos , Polietilenglicoles/química , Polímeros/química , Ácidos Polimetacrílicos/química , Reproducibilidad de los Resultados
15.
ACS Appl Mater Interfaces ; 7(1): 553-62, 2015 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-25434705

RESUMEN

Due to its good properties such as low cytotoxicity, degradability, and biocompatibility, poly(aspartic acid) (PAsp) is a good candidate for the development of new drug delivery systems. In this work, a series of new PAsp-based degradable supramolecular assemblies were prepared for effective gene therapy via the host-guest interactions between the cyclodextrin (CD)-cored PAsp-based polycations and the pendant benzene group-containing PAsp backbones. Such supramolecular assemblies exhibited good degradability, enhanced pDNA condensation ability, and low cytotoxicity. More importantly, the gene transfection efficiencies of supramolecular assemblies were much higher than those of CD-cored PAsp-based counterparts at various N/P ratios. In addition, the effective antitumor ability of assemblies was demonstrated with a suicide gene therapy system. The present study would provide a new means to produce degradable supramolecular drug delivery systems.


Asunto(s)
Vectores Genéticos , Péptidos/química , Transfección , Antineoplásicos/química , Benceno/química , Cationes , Supervivencia Celular , Ciclodextrinas/química , ADN/química , Sistemas de Liberación de Medicamentos , Terapia Genética/métodos , Células HEK293 , Células Hep G2 , Humanos , Microscopía de Fuerza Atómica , Tamaño de la Partícula , Plásmidos/metabolismo , Polímeros/química
16.
Clin Implant Dent Relat Res ; 15(6): 918-26, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23710654

RESUMEN

OBJECTIVE: To display an inlay technique of osteotome sinus floor elevation using a trephine combined with simultaneous short implant placement where the residual bone height (RBH) is less than 5 mm, as well as to evaluate the clinical effect in a prospective study. MATERIAL AND METHODS: Fifty short implants were installed in 32 patients in the severely atrophic posterior maxilla immediately after sinus floor elevation between January 2010 and October 2012. An inlay osteotome sinus augmentation technique using a trephine was applied in the operation. The mean residual bone height adjacent to or beneath the sinus was 3.34 mm, ranging from 0.96 mm to 4.96 mm. It was rarely necessary to add graft material from bovine sources in this therapy. With the purpose of bite training and soft tissue reforming, the temporary crowns were fixed after 6 months. The final prostheses were restored 3 months later. The stability and osseointegration of the implants were clinically evaluated, also the bone height gain around the implants was measured. RESULTS: The survival rate was 100% during the study period with this procedure. Each of the implants, loaded without pain or any subjective sensation, was clinically stable. No implants had detectable sinus membrane perforation during operation. The radiographic results demonstrated that the bone height gain was 5.38 mm after the surgery. CONCLUSION: Based on the results and within the limits of the present study, it can be suggested that short implant placement in conjunction with this inlay osteotome sinus augmentation technique could yield predictable clinical results for edentulous posterior maxillary region with RBH less than 5 mm. Besides, from the clinical point of view, these techniques may reduce the indication for complex invasive procedures and simplify treatment in the posterior.


Asunto(s)
Huesos/anatomía & histología , Implantes Dentales , Osteotomía , Elevación del Piso del Seno Maxilar/métodos , Fracaso de la Restauración Dental , Estudios de Seguimiento , Humanos , Estudios Prospectivos
17.
Nanoscale ; 4(7): 2470-7, 2012 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-22373876

RESUMEN

Direct bulk growth of single-walled carbon nanotubes (SWCNTs) with required properties, such as diameter, length, and chirality, is the first step to realize their advanced applications in electrical and optical devices, transparent conductive films, and high-performance field-effect transistors. Preferential growth of short aligned, metallic-rich SWCNTs is a great challenge to the carbon nanotube community. We report the bulk preferential growth of short aligned SWCNTs from perpendicular Mo-containing FeMgAl layered double hydroxide (LDH) film by a facile thermal chemical vapor deposition with CH(4) as carbon source. The growth of the short aligned SWCNTs showed a decreased growth velocity with an initial value of 1.9 nm s(-1). Such a low growth velocity made it possible to get aligned SWCNTs shorter than 1 µm with a growth duration less than 15 min. Raman spectra with different excitation wavelengths indicated that the as-grown short aligned SWCNTs showed high selectivity of metallic SWCNTs. Various kinds of materials, such as mica, quartz, Cu foil, and carbon fiber, can serve as the substrates for the growth of perpendicular FeMoMgAl LDH films and also the growth of the short aligned SWCNTs subsequently. These findings highlight the easy route for bulk preferential growth of aligned metallic-rich SWCNTs with well defined length for further bulk characterization and applications.


Asunto(s)
Hidróxidos/química , Metales/química , Nanotubos de Carbono/química , Aluminio/química , Materiales Biocompatibles Revestidos/síntesis química , Materiales Biocompatibles Revestidos/química , Cristalización , Hierro/química , Magnesio/química , Nanopartículas del Metal/química , Modelos Biológicos , Molibdeno/química , Concentración Osmolar
18.
Int J Nanomedicine ; 6: 1853-61, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21931481

RESUMEN

Infection around membranes is often found in guided bone regeneration (GBR). The excellent antibacterial properties of Ag-nHA-nTiO(2)/polyamide-66 (PA66) nanocomposite membranes have been demonstrated previously. The aim of this study was to observe the microstructure of an Ag-nHA-nTiO(2)/PA66 membrane and its effects on osteoblast-like cells in vitro. An Ag-nHA-nTiO(2)/PA66 membrane was used in the experimental group, and both nHA/PA66 and expanded poly tetrafluroethylene (e-PTFE) membranes were set as control. MG63 osteoblast-like cells were cultured on the three kinds of membrane and tissue culture polystyrene (TCP). The microstructure of the above membranes and the cells adhered on them were detected by scanning electronic microscope (SEM). Cell proliferation was determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, cell viability with a cell viability analyzer, and alkaline phosphatase (ALP) activity and Ca(2+) concentration of osteoblast-like cell matrix by enzyme-linked immunosorbent assay. SEM showed that both Ag-nHA-nTiO(2)/PA66 membranes and nHA/PA66 membranes were composed of porous obverse face and smooth opposite face. The e-PTFE membranes showed elliptic surface structure with many tiny lined cracks. The MG63 cells adhered and proliferated well on all three kinds of membranes. Though cell viability on Ag-nHA-nTiO(2)/PA66 membranes was significantly lower than that of the control groups (P < 0.05), MTT values, ALP activity, and Ca(2+) concentration did not differ significantly among the three kinds of membranes (P > 0.05). From these findings, it can be concluded that Ag-nHA-nTiO(2)/PA66 membranes are as biocompatible as nHA/ PA66 membranes and TCP, thus may be applied safely in GBR.


Asunto(s)
Antibacterianos/farmacología , Osteoblastos/citología , Fosfatasa Alcalina/metabolismo , Antibacterianos/química , Regeneración Ósea , Calcio/metabolismo , Adhesión Celular , Línea Celular , Proliferación Celular , Supervivencia Celular , Durapatita , Regeneración Tisular Dirigida/métodos , Humanos , Membranas Artificiales , Microscopía Electrónica de Rastreo , Nanocompuestos/química , Nanocompuestos/ultraestructura , Nanomedicina , Nylons , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Politetrafluoroetileno , Plata/farmacología , Titanio/farmacología
19.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 29(1): 44-7, 52, 2011 Feb.
Artículo en Zh | MEDLINE | ID: mdl-21427899

RESUMEN

OBJECTIVE: Clinical cases of immediate loaded implants were retrospectively analyzed, in the aim of evaluating the clinical value of immediate loading. METHODS: From July 2005 to October 2009, 99 immediate loaded implants were implanted in 29 patients. The overall data including radiography, clinical examination were collected during the follow-up periods ranged from 4 to 46 months. The implants were evaluated with the survival rate, bone resorption, soft tissue esthetics (including gingiva papilla index and pink esthetic score). RESULTS: Survival rate for immediate loaded implant was 97.0%. The average bone resorption were 0.22 mm at 4-6 months after surgery, bone increase of 0.15 mm were found at 6-12 month, and bone increase up to 0.16 mm at 12-46 months. The gingival papilla index was 2.68, while pink esthetic score was 12.58. CONCLUSION: Immediate loaded implant is an effective repairing method for patients missing teeth and the esthetics effect is ideal.


Asunto(s)
Implantes Dentales de Diente Único , Carga Inmediata del Implante Dental , Adulto , Coronas , Humanos , Masculino , Maxilar , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
20.
Zhonghua Liu Xing Bing Xue Za Zhi ; 27(3): 256-9, 2006 Mar.
Artículo en Zh | MEDLINE | ID: mdl-16792902

RESUMEN

OBJECTIVE: To explore the correlation between angiographically-defined coronary heart disease (CHD) and chronic periodontitis (CP). METHODS: 277 cases with CHD (case group) and another 238 with no agiographic evidence of CHD (control group) were compared on their traditional cardiovascular risk factors, as: oral health status and probing depth, clinical attachment level, gingival recession, as well as number of missing teeth. Other related risk factors of CHD were included in a stepwise logistic regression analysis. RESULTS: Data from univariate analysis showed that there was significant difference in CP, plasma triglyceride, high density lipoprotein cholesterol (HDL-C), fast glucose, white blood count, hypertension and smoking between patients with CHD and those with out CHD (P < 0.01 - 0.001). Multiple factorial logistic regression analysis showed that CP, hypertension, diabetes mellitus, HDL-C were strongly correlated with the incidence of CHD. Significant dosage-effective response was also found in the relationship between CP and CHD (P < 0.001). Further studies also suggested that the severity of CP paralleled the severity of CHD. CONCLUSION: The results indicated that CP might serve as an independent risk factor of CHD and significantly enhance the risk and severity of CHD. Our study suggested that the elimination of probable risk factors in oral cavity was indispensable during the process of the prevention of CHD in order to prevent acute coronary events.


Asunto(s)
Enfermedad Coronaria/epidemiología , Periodontitis/epidemiología , Angiografía , Biomarcadores/sangre , Estudios de Casos y Controles , Enfermedad Crónica , Humanos , Salud Bucal , Factores de Riesgo
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