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1.
Clin Oral Implants Res ; 34(6): 639-650, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36916464

RESUMO

OBJECTIVE: To present the results of guided bone regeneration (GBR) with three-dimensional printing individualized titanium mesh (3D-PITM) applied to alveolar bone defects with different Terheyden classifications and the factors affecting the osteogenic outcome. MATERIALS AND METHODS: Fifty-nine patients, presenting with 61 defect sites, were enrolled between 2018 and 2021. GBR+3D-PITM was obtained with simultaneous or second stage implant placement. The complication rate, the success rate of the bone grafting procedure and the survival rate of the implant were documented. Bone gain, thickness of pseudo-periosteum and peri-implant marginal bone loss (MBL) were measured through digital methods by imaging data (CBCT and X-ray). RESULTS: Out of 61 sites, 20 were exposed (exposure rate: 32.8%). The width, height, and volume bone gain at P3 (mesh removal) were 5.22 ± 3.19 mm, 5.01 ± 2.83 mm, and 588.91 ± 361.23 mm3 , respectively. From P2 (3D-PITM+GBR) to P3 , changes in bone gain were not statistically different in the different Terheyden classifications, the occurrence of exposure (p < .001 for all dimensions) and the different type of pseudo-periosteum (p = .030 for width and p = .002 for height) were significantly correlated with the reduction of bone gain. Terheyden classification of the defect sites was significantly associated with the occurrence of exposure (p = .014) and types of the pseudo-periosteum (p = .015). CONCLUSION: The 3D-PITM can be used in alveolar bone defects with different Terheyden classification, but cases with severe vertical bone defects have a greater chance of the 3D-PITM exposure and the exposure can affect the outcome of bone augmentation.


Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Humanos , Implantação Dentária Endóssea , Titânio , Estudos Retrospectivos , Telas Cirúrgicas , Regeneração Óssea , Impressão Tridimensional , Transplante Ósseo , Aumento do Rebordo Alveolar/métodos
2.
Angew Chem Int Ed Engl ; 61(16): e202114504, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35106878

RESUMO

Fertilization and early embryonic development as the beginning of a new life are key biological events. Hydrogen polysulfide (H2 Sn ) plays important roles during physiological regulation, such as antioxidation-protection. However, no report has studied in situ H2 Sn fluctuation during early embryonic development because of the low abundance of H2 Sn and inadequate sensitivity of probes. We herein construct a polymeric nanobeacon from a H2 Sn -responsive polymer and fluorophores, which is capable of detecting H2 Sn selectively and of signal amplification. Taking the zebrafish as a model, the polymeric nanobeacon revealed that the H2 Sn level was significantly elevated after fertilization due to the activation of cell multiplication, suppressed partially during embryonic development, and finally kept steady up to zebrafish emergence. This strategy is generally accessible for biomarkers by altering the responsive unit and significant for facilitating biological analysis during life development.


Assuntos
Hidrogênio , Peixe-Zebra , Animais , Desenvolvimento Embrionário , Fertilização , Polímeros , Sulfetos
3.
Anal Chem ; 93(38): 12944-12953, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34523923

RESUMO

For sensing low abundance of biomarkers, utilizing nanocarriers to load dyes is an efficient method to amplify the detected signal. However, the non-specific leak of the internal dyes in this approach is accompanied by false positive signals, resulting in inaccurate signal acquirement. To address this issue, in this work, we reported a novel signal amplification strategy with dye as a scaffold to construct a self-immolative dye-doped polymeric probe (SDPP). In our proposed approach, the dyes were covalently integrated into the main chain of a polymer, which can avoid the non-specific leak of the dye when used in a rigorous biological environment, thus evading the false positive signal. As a prototype of this concept, a SDPP, which responds to hydroxyl radicals (•OH), was rationally fabricated. Upon being activated by •OH, SDPP will liberate the dye through a self-immolative reaction to bind with protein for amplifying the fluorescence signal. Compared with a dye-loaded nanoprobe, SDPP can precisely track intracellular basal •OH levels and visualize the •OH associated with myocarditis in vivo. More importantly, the attempt in this work not only provides an effective molecular tool to investigate the role of •OH in cardiopathy, but also puts forward a new direction to current signal-amplifying strategies for precisely and reliably acquiring the intracellular molecular information.


Assuntos
Corantes , Radical Hidroxila , Diagnóstico por Imagem , Corantes Fluorescentes , Polímeros , Espectrometria de Fluorescência
4.
Mikrochim Acta ; 186(9): 636, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432257

RESUMO

The preparation of an organic polymer monolithic column modified with an amino acid ionic liquid and graphene oxide (AAIL-GO) and its application to capillary electrochromatography (CEC) was described. The AAIL tetramethylammonium-L-arginine was bonded to a monolithic column that was previously modified with graphene oxide by using an hydrochloride/N-hydroxysuccinimide coupling reaction. The morphology of a poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith was examined by scanning electron microscopy. The incorporation of AAIL and graphene oxide was detected by infrared spectroscopy and elemental analysis. The resulting monolithic column produced a strong and stable electroosmotic flow from the anode to the cathode in the pH range from 3 to 9. Compared with a column modified with AAIL or graphene oxide only, the AAIL-GO-modified column has a better separation ability for amino acids, ß-blockers, and nucleotides (the resolution of three amino acids: 2.231 and 2.036, ß-blockers: 2.779 and 2.470 and nucleotides: 8.345 and 3.321). Molecular modeling was applied to demonstrate the separation mechanism of small molecules which showed a good support for experimental results. Graphical abstract Schematic representation of capillary electrochromatography (CEC) systems with an amino acid ionic liquid-graphene oxide modified organic polymer monolithic column as stationary phases for separation of amino acids, ß-blockers, and nucleotides.


Assuntos
Antagonistas Adrenérgicos beta/isolamento & purificação , Aminoácidos/química , Eletrocromatografia Capilar , Grafite/química , Líquidos Iônicos/química , Nucleotídeos/isolamento & purificação , Polímeros/química , Antagonistas Adrenérgicos beta/química , Aminoácidos/isolamento & purificação , Estrutura Molecular , Nucleotídeos/química , Tamanho da Partícula , Propriedades de Superfície
5.
Anal Chem ; 84(15): 6308-11, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22769867

RESUMO

Although electrospray-differential mobility analyzers (ES-DMA) have been previously employed to characterize ligand binding to nanoparticles, absolute quantification of surface coverage can be inaccurate at times because of ligand conformational effects. In this Letter, we report a quantitative technique by in-flight coupling of a particle mass analyzer (APM) with ES-DMA, thus enabling a direct quantitative analysis of mass independent of particle size, material, morphology and conformation. We demonstrate the utility of ES-DMA-APM by studying two model complex systems (gold nanoparticle-bovine serum albumin and polystyrene bead-antibody) as a function of concentration and pH. Our results obtained with ES-DMA-APM are in excellent agreement with prior work. We anticipate that this will enhance the capabilities of online quantitative characterization of ligand binding to nanoparticles.


Assuntos
Ligantes , Nanopartículas Metálicas/química , Espectrometria de Massas em Tandem , Adsorção , Animais , Bovinos , Ouro/química , Concentração de Íons de Hidrogênio , Poliestirenos/química , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo
6.
Environ Sci Pollut Res Int ; 29(10): 13893-13904, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34599452

RESUMO

In this work, polymers containing a large number of benzene rings and multiple functional groups were designed to remove aromatic organic pollutants. Using tetrafluoroterephthalonitrile (TFTPN) as a rigid crosslinking agent to crosslink different functionalized phenylcarbamoylated-ß-cyclodextrin derivatives to prepare a series of porous multifunctional cyclodextrin (CD) polymerizations, including three preliminary polymerized adsorption materials and a mix ß-cyclodextrin polymer (X-CDP) prepared via a secondary crosslinking procedure of the above three materials. The X-CDP preparation process connects the pre-formed nanoparticles and increases the presence of linkers inside the particles. At the same time, X-CDP exhibited porous structure with various functional groups such as nitro, chlorine, fluorine, and hydroxyl. Those special characteristics render this material with good adsorption ability towards various aromatic organic pollutants in water, including tetracycline, ibuprofen, dichlorophenol, norfloxacin, bisphenol A, and naphthol. Especially, the maximum adsorption capacity for tetracycline at equilibrium reached 110.56 mg·g-1, which is competitive with the adsorption capacities of other polysaccharide adsorbents. X-CDP removed organic contaminants much more quickly than other adsorbents, reaching almost ~95% of its equilibrium in only 30 s, and the rate constant reaches 2.32 g·mg-1·min-1. The main adsorption process of the pollutants by X-CDP fitted the pseudo-second-order kinetic and Langmuir isotherm well, indicating that the adsorption process is monolayer adsorption. Moreover, X-CDP possessed the good reusability where the pollutant removal rate was only reduced 8.3% after five cycles. Such advantages render the polymer great potential in the rapid treatment of organic pollutants in water bodies.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Purificação da Água , beta-Ciclodextrinas , Adsorção , Polímeros , Porosidade , Poluentes Químicos da Água/análise
7.
Front Bioeng Biotechnol ; 10: 1036061, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324890

RESUMO

Apical periodontitis is a common clinical disease caused by bacteria; bacterial metabolites can cause an imbalance in bone homeostasis, bone mass reduction, and tooth loss. Bone resorption in apical periodontitis causes a concentration of stress in the tooth and periodontal tissues during occlusion, which aggravates the disease. Emerging evidence indicates that bone morphogenetic protein 9 (BMP9), also known as growth differentiation factor 2(Gdf2), may play an important role in tooth and dentoalveolar development. Herein, we investigated the role of BMP9 in the development of apical periodontitis and its effects on the biomechanics of dentoalveolar bone. Apical periodontitis models were established in five BMP9 knockout (KO) mice and five C57BL/6 WT (wild-type) mice. At baseline and 14, 28, and 42 days after modeling, in vivo micro-computed tomography analysis and three-dimensional (3D) reconstruction were performed to evaluate the apical lesion in each mouse, and confirm that the animal models were successfully established. Finite element analysis (FEA) was performed to study the stress and strain at the alveolar fossa of each mouse under the same vertical and lateral stress. FEA revealed that the stress and strain at the alveolar fossa of each mouse gradually concentrated on the tooth cervix. The stress and strain at the tooth cervix gradually increased with time but were decreased at day 42. Under the same lingual loading, the maximum differences of the stress and strain at the tooth root in KO mice were greater than those in WT mice. Thus, these findings demonstrate that BMP9 could affect the biomechanical response of the alveolar fossa at the tooth root in mice with apical periodontitis. Moreover, the effects of BMP9 on the biomechanical response of the alveolar bone may be site-dependent. Overall, this work contributes to an improved understanding of the pathogenesis of apical periodontitis and may inform the development of new treatment strategies for apical periodontitis.

8.
Ann Plast Surg ; 67(5): 493-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21629112

RESUMO

The repair of fronto-orbital nasal bone defects may be a troublesome problem to plastic surgeons. This report aims to present the results of reconstruction of fronto-orbital nasal bone defects with the prefabrication of epoxied maleic acrylate/hydroxyapatite compound (EH compound) using 3-dimensional (3D) imaging data and computer-assisted manufacturing techniques, sometimes combined with autogenous bone to repair nasal defect. Helical computed tomography data were used to create a 3D model of the patient's skull. On the basis of these data, the individual shape of the implant was created by a computer-aided design/computer-aided manufacturing program. A rapid prototyping system was applied for production of the physical models. A total of 12 patients with traumatic fronto-orbital nasal defects were included in this study. The patients followed up for 1 to 24 months. The satisfactory results, such as excellent symmetry, stability, and normal fronto-orbital contours were obtained for all patients. The operating time was short without any complications. The depression of the region of fronto-orbital nasal bone defects always achieved an attractive or satisfactory prominence that was in balance and harmony with other facial features of all the patients. This method allows accurate fabrication of the implant. It improves the surgical techniques and reduces the risk of a second intervention, with improved aesthetic outcomes.


Assuntos
Resinas Acrílicas , Desenho Assistido por Computador , Durapatita , Osso Frontal/cirurgia , Processamento de Imagem Assistida por Computador , Osso Nasal/cirurgia , Órbita/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Próteses e Implantes , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Adulto Jovem
9.
J Craniofac Surg ; 22(5): 1806-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21959439

RESUMO

BACKGROUND: An augmented reality tool allows for visual tracking of real anatomic structures in superposition with volume-rendered computed tomographic or magnetic resonance imaging scans and thus can be used for navigated translocation of important structures during operation. In this feasibility study, ARToolKit was used in mandibular angle oblique split osteotomy to define the cutting planes according to an operative plan. METHODS: We overlay the operative plan on the model of a mandible made by rapid prototyping technology, and the technology was successfully used in 15 patients. Before the operation, all patients underwent computed tomographic scan, and dental casts were prepared by surgeons. Then, surgeons make the occlusal splint according to a dental cast to fix the marker, which can be recognized by the ARToolKit. The occlusal splint and marker were transformed to three-dimensional data using a laser scanner, and a programmer that runs on a personal computer named Rapidform matches the marker and the mandible image to generate the virtual image. By this step, the virtual image describing the marker, occlusal splint, and the mandible image of the patient are integrated. During the operation, the operative plan was overlaid on the rapid prototyping model of the mandible as soon as the ARToolKit recognized the marker. RESULTS: The technology was successfully used in 15 patients; the virtual image of the mandible and the cutting-plane both overlaid the real model of the mandible. CONCLUSIONS: This study has reported a new and effective way for mandibular angle oblique split osteotomy, and using occlusal splint might be a powerful option for the registration of augmented reality. Augmented reality tools like ARToolKit may be helpful for control of maxillary translocation in orthognathic surgery.


Assuntos
Mandíbula/cirurgia , Placas Oclusais , Procedimentos Cirúrgicos Ortognáticos/métodos , Humanos , Imageamento Tridimensional , Mandíbula/diagnóstico por imagem , Modelos Dentários , Software , Tomografia Computadorizada por Raios X
10.
Environ Pollut ; 265(Pt B): 114922, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32554087

RESUMO

Only limited information is available on bacterial communities' dynamics on tire microplastics in urban water environments. This study exploited 16S rDNA high-throughput sequencing to characterize bacterial communities on tire microplastics, using three different tire brands and tire sizes, in two typical urban water environments, including an influent pond of constructed wetland (CW) and its subsequent effluent into a landscape river (LR) during three different periods, namely, 1 month, 3 and 6 months. Results showed that the abundance of bacterial colonization on tire microplastics will increase over time. Proteobacteria, Bacteroidetes were the dominant bacteria at a phylum level, although they exhibited dynamic changes. At a genus level, the identifiable bacteria found in tire microplastics was generally the common bacteria in wastewater discharge, such as Aquabacterium and Denitratisoma. Additionally, alpha diversity showed no significant differences in bacterial communities at the same locations. While beta diversity showed that the bacterial communities on the tire microplastics in the two locations was different. BugBase revealed that tire microplastics could support pathogenic bacteria in urban water environments. PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) indicated that the abundance of microorganisms associated with metabolism and degradation increased with time. Moreover, the ambient environmental factors were the main influencing factors of bacterial communities on tire microplastics. Herein, the contribution rate of nutrient salts (NO2-N, NO3-N, NH4-N, CODcr) was approximately 63%, and that of environmental physical factors of T and pH was 50%. While physicochemical factors, including particle size, contact angle, element content only had a slight impact. Accordingly, tire microplastics, as an emerging environmental pollutant, can act as carries for bacterial colonization and propagation, particularly harmful microorganisms. Therefore, the obtained findings can provide new insight into potential risks of harmful microorganisms that colonize tire microplastics in urban water environments.


Assuntos
Plásticos , Água , Bactérias , Monitoramento Ambiental , Microplásticos , Filogenia
11.
Int J Biol Macromol ; 140: 119-128, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419562

RESUMO

Cellulose/graphene oxide (CG) porous composites with 3D network structure were prepared via a solution mixing-regeneration and freeze-drying process. The CG aerogels were functionalized with 1,4-butane sultone under mild reaction conditions to achieve sulfated composite aerogels (SCGs), in which the sulfo groups were simultaneously introduced onto GO and cellulose components. The adsorption ability of SCG aerogel was greatly enhanced compared with CG aerogels. The fitting results of adsorption models suggested the monolayer adsorption and chemisorptive characteristics with the maximal uptake capacity as high as 421.9 mg/g for methylene blue (MB) and 163.4 mg/g for tetracycline (TC). The adsorption mechanism was also studied in detail. For the simulated wastewater containing MB and TC, the novel SCG adsorbent exhibited a removal efficiency of 99%. Furthermore, its adsorption capacity was not apparently deteriorated after seven cycles for MB and ten cycles for TC while the original structural integrity was almost maintained. Herein, this recyclable and reusable adsorbent exhibited the potential application on the removal of MB and TC from water.


Assuntos
Celulose/química , Grafite/química , Azul de Metileno/química , Tetraciclina/química , Poluentes Químicos da Água/química , Purificação da Água , Porosidade
12.
Biomacromolecules ; 9(3): 1050-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18290627

RESUMO

By using acetyl tributyl citrate (ATBC) as the plasticizer of poly(lactic acid) (PLA) and carbon black (CB) as conductive filler, electrically conductive polymer composites (CPC) with different CB and ATBC contents were prepared. FTIR revealed that the interaction existed between PLA/ATBC matrix and CB filler and ATBC could improve this interaction. The rheology showed that ATBC could obviously decrease the shear viscosity and improve the fluidity of the composites but just the reverse for CB. With the increasing of CB contents, the enforcement effect, storage modulus, and glass-transition temperature increased but the elongation at break decreased. PLA/ATBC/CB composites exhibited the low electrical percolation thresholds of 0.516, 1.20, 2.46, and 2.74 vol % CB at 30, 20, 10, and 0 wt % ATBC. The conductivity of the composite containing 3.98 vol % CB and 30 wt % ATBC reached 1.60 S/cm. Scanning electron microscopy revealed that the addition of ATBC facilitated the dispersion of the CB in the PLA matrix. Water vapor permeability (WVP) showed that, at the same CB contents, the more ATBC contents there were, the less the values of WVP were.


Assuntos
Citratos/química , Resinas Compostas/química , Ácido Láctico/química , Polímeros/química , Fuligem/química , Citratos/análise , Resinas Compostas/síntese química , Condutividade Elétrica , Ácido Láctico/análise , Microscopia Eletrônica de Varredura , Poliésteres , Polímeros/análise , Porosidade , Reologia , Fuligem/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração , Volatilização , Água/química
13.
Chemosphere ; 202: 298-305, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29573615

RESUMO

A simple route is presented to fabricate carboxylic-functional carbon-coated polyacrylonitrile nanofibers (oPAN@C) through preoxidation and hydrothermal carbonization. PAN fibers were firstly preoxidized to form aromatic ladder structure with the resistance to hydrothermal condition, in which more carboxyl groups were introduced on the fiber surface at the present of chitosan and citric acid. The oPAN@C composites exhibit a high adsorption capacity towards methylene blue (MB) and lead ion (Pb2+). The adsorption data matched the pseudo-second-order kinetic model and Langmuir model well with the maximum adsorption capacity (153.37 and 143.27 mg g-1) for methylene blue and Pb2+, respectively. Moreover, oPAN@C could be regenerated easily by hydrochloric acid, and still remained high removal efficiency after 5 cycles. Therefore, oPAN@C fibers should have potential application in sewage treatment.


Assuntos
Resinas Acrílicas/química , Carbono/química , Cátions/química , Azul de Metileno/química , Nanofibras/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Cinética
14.
Chemosphere ; 165: 399-408, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27668717

RESUMO

Porous cellulose spheres (PCS) were fabricated by precipitating the spheres from a cellulose ionic liquid solution, followed by freezing, solvent exchange, and drying. PCS had low crystallinity and a large surface area that facilitated modification with trisodium trimetaphosphate (STMP) to introduce phosphate ester groups into the porous structure of the heterogeneous system. The STMP-modified PCS (SPCS) were used to remove heavy metal ions from aqueous solution. With increasing STMP dosage, the adsorption capacity of SPCS obviously improved due to chelation between Pb2+ and phosphate ester groups. The kinetic adsorption and isotherm data matched the pseudo-second order model and the Langmuir model well. The maximum adsorption capacity reached 150.6 mg g-1 for SPCS. SPCS were competitive with other absorbents because the phosphate ester groups and porous structure contributed to Pb2+ adsorption. Moreover, SPCS can be regenerated with ethylenediamine tetraacetic acid disodium salt (EDTA) solution for repetitious adsorption of Pb2+.


Assuntos
Celulose/química , Recuperação e Remediação Ambiental/métodos , Chumbo/análise , Chumbo/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Polifosfatos/química , Porosidade
15.
Mater Sci Eng C Mater Biol Appl ; 66: 92-99, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27207042

RESUMO

Drug-eluting stents with biodegradable polymers as reservoirs have shown great potential in the application of interventional therapy due to their capability of local drug delivery. Herein, poly(l-lactide-co-ε-caprolactone) (PLCL) with three different compositions as carriers for ciprofloxacin lactate (CIP) was coated on ureteral stents by the dipping method. To simulate a body environment, degradation behavior of PLCL as both the bulk film and the stent coating was evaluated in artificial urine (AU, pH6.20) respectively at 37°C for 120days by tracing their weight/Mn loss, water absorption and surface morphologies. Furthermore, the release profile of the eluting drug CIP on each stent exhibited a three-stage pattern, which was greatly affected by the degradation behavior of PLCL except for the burst stage. Interestingly, the degradation results on both macroscopic and molecular level indicated that the release mechanism at stage I was mainly controlled by chain scission instead of the weight loss or morphological changes of the coatings. While for stage II, the release profile was dominated by erosion resulting from the hydrolysis reaction autocatalyzed by acidic degradation residues. In addition, ciprofloxacin-loaded coatings displayed a significant bacterial resistance against E. coli and S. aureus without obvious cytotoxicity to Human foreskin fibroblasts (HFFs). Our results suggested that PLCL copolymers with tunable degradation rate as carriers for ciprofloxacin lactate could be used as a promising long-term antibacterial coating for ureteral stents.


Assuntos
Antibacterianos/química , Ciprofloxacina/química , Portadores de Fármacos/química , Stents Farmacológicos , Antibacterianos/farmacologia , Antibacterianos/urina , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ciprofloxacina/farmacologia , Ciprofloxacina/urina , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Microscopia Eletrônica de Varredura , Poliésteres/química , Staphylococcus aureus/efeitos dos fármacos
16.
PLoS One ; 9(4): e94277, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24736242

RESUMO

Reaumuria soongorica (Pall.) Maxim., a resurrection semi-shrub, is a typical constructive and dominant species in desert ecosystems in northwestern China. However, the gene expression characteristics of R. soongorica under drought stress have not been elucidated. Digital gene expression analysis was performed using Illumina technique to investigate differentially expressed genes (DEGs) between control and PEG-treated samples of R. soongorica. A total of 212,338 and 211,052 distinct tags were detected in the control and PEG-treated libraries, respectively. A total of 1,325 genes were identified as DEGs, 379 (28.6%) of which were up-regulated and 946 (71.4%) were down-regulated in response to drought stress. Functional annotation analysis identified numerous drought-inducible genes with various functions in response to drought stress. A number of regulatory proteins, functional proteins, and proteins induced by other stress factors in R. soongorica were identified. Alteration in the regulatory proteins (transcription factors and protein kinase) may be involved in signal transduction. Functional proteins, including flavonoid biosynthetic proteins, late embryogenesis abundant (LEA) proteins, small heat shock proteins (sHSP), and aquaporin and proline transporter may play protective roles in response to drought stress. Flavonoids, LEA proteins and sHSP function as reactive oxygen species scavenger or molecular chaperone. Aquaporin and proline transporters regulate the distribution of water and proline throughout the whole plant. The tolerance ability of R. soongorica may be gained through effective signal transduction and enhanced protection of functional proteins to reestablish cellular homeostasis. DEGs obtained in this study may provide useful insights to help further understand the drought-tolerant mechanism of R. soongorica.


Assuntos
Secas , Perfilação da Expressão Gênica , Folhas de Planta/genética , Polietilenoglicóis/farmacologia , Estresse Fisiológico/genética , Tamaricaceae/genética , Tamaricaceae/fisiologia , Engenharia Genética , Folhas de Planta/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Tamaricaceae/efeitos dos fármacos
17.
Biomaterials ; 35(6): 2066-78, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24315577

RESUMO

Our previous study had reported that cholesterol-grafted poly(amidoamine) (rPAA-Chol polymer) was able to self-assemble into cationic nanoparticles and act as a potential carrier for siRNA transfection. In this study, the core-shell type lipid/rPAA-Chol hybrid nanoparticles (PEG-LP/siRNA NPs and T7-LP/siRNA NPs) were developed for improving in vivo siRNA delivery by modifying the surface of rPAA-Chol/siRNA nanoplex core with a lipid shell, followed by post-insertion of polyethylene glycol phospholipid (DSPE-PEG) and/or peptide (HAIYPRH, named as T7) modified DSPE-PEG-T7. The integrative hybrid nanostructures of LP/siRNA NPs were evidenced by dynamic light scattering (DLS), confocal laser scanning microscope (CLSM), cryo-transmission electron microscope (Cryo-TEM) and surface plasmon resonance (SPR) assay. It was demonstrated that the T7 peptide modified LP/siRNA NPs (T7-LP/siRNA NPs) exhibited uniform and spherical structures with particle size of 99.39 ± 0.65 nm and surface potential of 42.53 ± 1.03 mV, and showed high cellular uptake efficiency and rapid endosomal/lysosomal escape ability in MCF-7 cells. Importantly, in vitro gene silencing experiment demonstrated that both of pegylated and targeted LP/siEGFR NPs exhibited significantly stronger downregulation of EGFR protein expression level in MCF-7 cells, compared to that of the physical mixture of siRNA lipoplexes and rPAA-Chol/siRNA nanoplexes. In vivo tumor therapy on nude mice bearing MCF-7 tumors further confirmed that the targeted T7-LP/siEGFR NPs exhibited the greatest inhibition on tumor growth via transferrin receptor-mediated targeting delivery, without any activation of immune responses and significant body weight loss following systemic administration. These findings indicated that the core-shell type T7-LP/siRNA nanoparticles would be promising siRNA delivery systems for in vivo tumor-targeted therapy.


Assuntos
Nanopartículas/química , Polímeros/química , RNA Interferente Pequeno/química , Animais , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Citometria de Fluxo , Humanos , Células MCF-7 , Camundongos , Microscopia Confocal , Polietilenoglicóis/química , RNA Interferente Pequeno/fisiologia , Ressonância de Plasmônio de Superfície
18.
Carbohydr Polym ; 94(1): 63-70, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23544510

RESUMO

The graphite was oxidized to prepare graphene oxide (GO), and GO was reduced by glucose to obtain reduced graphene oxide (RGO) sheet. There were abundant and residual oxygen-containing groups on GO and RGO, respectively. Compared to graphite, the GO and RGO sheets appeared flat and transparent, and the aqueous suspensions followed the Lambert-Beer's law well. The composites were also fabricated by using GO and RGO as the filler in plasticized-starch (PS) matrix. Because of more oxygen-containing groups, GO could form the stronger interaction with PS matrix than RGO. And GO/PS composites exhibited better tensile strength, elongation at break and moisture barrier than RGO/PS composites, but lower thermal stability. GO/PS composites could protect against UV light, while the conductivities of RGO/PS composites could reach 1.07×10(-4), 6.92×10(-4) and 0.01 S/cm, respectively stored at RH50, 75 and 100%.


Assuntos
Grafite/química , Plásticos/química , Amido/análogos & derivados , Amido/química , Condutividade Elétrica , Temperatura Alta , Oxirredução , Permeabilidade , Solanum tuberosum/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Propriedades de Superfície , Resistência à Tração , Temperatura de Transição
19.
Biomaterials ; 34(21): 5303-16, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23570718

RESUMO

In this study, a series of bioreducible poly(amidoamine)s grafting different percentages of cholesterol (rPAA-Ch14: 14%, rPAA-Ch29: 29%, rPAA-Ch57: 57% and rPAA-Ch87: 87%) was synthesized and used for siRNA delivery. These amphiphilic polymers were able to self-assemble into cationic nanoparticles in aqueous solution at low concentrations. The nanoparticle formation was evidenced via cryo-transmission electron microscope (Cryo-TEM) and dynamic light scattering analysis. The average hydrodynamic size of rPAA-Ch blank nanoparticles was about 80-160 nm with zeta potential of 50-60 mV. Also, the effects of different percentages of cholesterol grafted onto rPAA on physicochemical characteristics, in vitro cytotoxicity, cellular uptake, VEGF gene silencing efficacy and translocation mechanism of rPAA-Ch/siRNA complexes were investigated. The results showed that rPAA-Ch57 polymer was not only able to form stable nanocomplexes and possess high cell uptake, but also to exhibit the best in vitro VEGF gene silencing efficacy and the best in vivo tumor growth inhibition effect when it was formulated with VEGF-siRNA. Moreover, the observations of confocal laser scanning microscope (CLSM) and the study of cholesterol competitive inhibition demonstrated that endosomal/lysosomal escape and cytoplasmic dissociation of rPAA-Ch57/siRNA complexes were dependent on the "proton sponge effect" and disulfide cleavage, following internalization with cholesterol-related endocytosis pathway and subsequent transportion into endosomes/lysosomes. These findings indicated that the rPAA-Ch57 polymer should be a promising and potent carrier for siRNA delivery.


Assuntos
Colesterol/química , Técnicas de Transferência de Genes , Nanopartículas/química , Poliaminas/química , RNA Interferente Pequeno/metabolismo , Animais , Cátions , Proliferação de Células , Endocitose , Endossomos/metabolismo , Feminino , Inativação Gênica , Humanos , Espaço Intracelular/metabolismo , Lisossomos/metabolismo , Células MCF-7 , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Nus , Nanopartículas/ultraestrutura , Oxirredução , Tamanho da Partícula , Poliaminas/síntese química , Polietilenoimina/química , Fator A de Crescimento do Endotélio Vascular/genética
20.
Se Pu ; 30(1): 95-8, 2012 Jan.
Artigo em Zh | MEDLINE | ID: mdl-22667100

RESUMO

A method for the determination of bisphenol A in the plastic parts of small household appliances by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. The sample was extracted with accelerated solvent extraction (ASE) and purified by Sep-Pak C18 solid phase extraction. Bisphenol A was separated and detected using LC-MS/MS in negative ion mode with the mobile phases of methanol and water (containing 0.05% ammonia water). The linearity of the method was good in the range of 5 µg/L to 100 µg/L. The recoveries for the spiked sample were from 95.2% to 109.7% at the three levels, 10, 25 and 75 µg/kg. The relative standard deviations were less than 3.8%. The limit of detection was 10 µg/kg. The method is easy-handling, time-saving, sensitive and suitable for the determination of the residual bisphenol A in the plastic parts of household appliances.


Assuntos
Compostos Benzidrílicos/análise , Cromatografia Líquida , Utensílios Domésticos , Fenóis/análise , Plásticos/química , Espectrometria de Massas em Tandem , Cromatografia Líquida/métodos , Poluentes Ambientais/análise , Espectrometria de Massas em Tandem/métodos
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