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1.
Proc Natl Acad Sci U S A ; 119(19): e2106965119, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35522709

RESUMO

Protein scaffolds direct the organization of amorphous precursors that transform into mineralized tissues, but the templating mechanism remains elusive. Motivated by models for the biomineralization of tooth enamel, wherein amyloid-like amelogenin nanoribbons guide the mineralization of apatite filaments, we investigated the impact of nanoribbon structure, sequence, and chemistry on amorphous calcium phosphate (ACP) nucleation. Using full-length human amelogenin and peptide analogs with an amyloid-like domain, films of ß-sheet nanoribbons were self-assembled on graphite and characterized by in situ atomic force microscopy and molecular dynamics simulations. All sequences substantially reduce nucleation barriers for ACP by creating low-energy interfaces, while phosphoserines along the length of the nanoribbons dramatically enhance kinetic factors associated with ion binding. Furthermore, the distribution of negatively charged residues along the nanoribbons presents a potential match to the Ca­Ca distances of the multi-ion complexes that constitute ACP. These findings show that amyloid-like amelogenin nanoribbons provide potent scaffolds for ACP mineralization by presenting energetically and stereochemically favorable templates of calcium phosphate ion binding and suggest enhanced surface wetting toward calcium phosphates in general.


Assuntos
Proteínas do Esmalte Dentário , Nanotubos de Carbono , Amelogenina/química , Proteínas Amiloidogênicas , Sítios de Ligação , Fosfatos de Cálcio
2.
Environ Sci Technol ; 57(11): 4533-4542, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36869003

RESUMO

Profound understanding of fouling behaviors and underlying mechanisms is fundamentally important for fouling control in membrane-based environmental applications. Therefore, it entails novel noninvasive analytical approaches for in situ characterizing the formation and development of membrane fouling processes. This work presents a characterization approach based on hyperspectral light sheet fluorescence microscopy (HSPEC-LSFM), which is capable of discriminating various foulants and providing their 2-dimensional/3-dimensional spatial distributions on/in membranes in a label-free manner. A fast, highly sensitive and noninvasive imaging platform was established by developing a HSPEC-LSFM system and further extending it to incorporate a laboratory-scale pressure-driven membrane filtration system. Hyperspectral data sets with a spectral resolution of ∼1.1 nm and spatial resolution of ∼3 µm as well as the temporal resolution of ∼8 s/plane were obtained, and the fouling formation and development process of foulants onto membrane surfaces, within the pores and on the pore walls were clearly observed during the ultrafiltration of protein and humic substances solutions. Pore blocking/constriction at short times while cake growth/concentration polarization at longer times was found to have coupled effects for the flux decline in these filtration tests, and yet the contribution of each effect as well as the transition of the governing mechanisms was found distinct. These results demonstrate in situ label-free characterization of membrane fouling evolution with the recognition of foulant species during filtration and provide new insights into membrane fouling. This work offers a powerful tool to investigate dynamic processes for a wide range of membrane-based explorations.


Assuntos
Ultrafiltração , Purificação da Água , Purificação da Água/métodos , Membranas Artificiais , Filtração/métodos , Substâncias Húmicas , Imagem Óptica
3.
J Exp Bot ; 73(11): 3477-3495, 2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35188965

RESUMO

The production of Arabidopsis seed mucilage involves complex polysaccharide biosynthetic pathways and developmental processes in seed epidermal cells. Although the polysaccharide components of Arabidopsis seed mucilage have been identified, their regulatory mechanism requires further investigation. Here, we show that Class II KNOX gene family members KNAT3 and KNAT7 play an essential role in regulating mucilage production in the early developmental stages of Arabidopsis seeds. Double mutant knat3knat7 resulted in defective seed mucilage production and columellae formation, whereas knat3 showed a normal phenotype compared with wild type, and the mucilage thickness in knat7 was slightly disturbed. Rhamnogalacturonan I (RG-I) and its biosynthetic substrates galacturonic acid and rhamnose were reduced in both the adherent and soluble mucilage of knat3knat7. Comparative transcriptome analysis on whole seeds suggested that polysaccharide, glucosinolate and anthocyanin biosynthetic pathways were specifically repressed in knat3knat7. Transient co-expression of KNAT3 and KNAT7 with promoter regions of candidate genes in Arabidopsis protoplasts revealed that both KNAT3 and KNAT7 act as positive regulators of the RG-I biosynthetic gene MUCILAGE-MODIFIED 4 (MUM4, AT1G53500). Collectively, our results demonstrate that KNAT3 and KNAT7 are multifunctional transcription factors in secondary cell wall development and redundantly modulate mucilage biosynthesis in Arabidopsis seeds.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Mucilagem Vegetal , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Mucilagem Vegetal/metabolismo , Polissacarídeos/metabolismo , Proteínas Repressoras/metabolismo , Sementes/genética , Sementes/metabolismo
4.
Am J Orthod Dentofacial Orthop ; 162(5): 777-792, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35985965

RESUMO

A 22-year-old woman visited the hospital complaining of lip protrusion, crowded teeth, and a gummy smile. The clinical examination showed a convex profile with a hyperdivergent mandible and a severe gummy smile in both anterior and posterior regions. The unstable mandible position was considered during treatment planning, and a targeted mechanic system was carefully designed. Temporary skeletal anchorage devices in the posterior dental region and a transpalatal arch were introduced as anchorage for the intrusion of the entire maxillary dentition and controlled retraction of the anterior teeth. Based on effective and simple mechanisms, we successfully eliminated the severe gummy smile and improved the facial aesthetics with the aid of conventional appliances. This approach provided an alternative option to orthognathic surgery or bulky invasive miniscrews for treatment of skeletal Class II malocclusion with severe gummy smile.

5.
Am J Orthod Dentofacial Orthop ; 161(6): e544-e553, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35311653

RESUMO

INTRODUCTION: Smile analysis in horizontally angled views is indispensable for esthetic assessment and could reveal teeth-to-lip disharmony, which might escape discovery in the frontal and profile views. However, evidence is lacking on where the anterior teeth should be positioned for esthetics in angled smiles. METHODS: Based on 3-dimensional facial image processing and geometric analysis, the lip edges were projected to the horizontal plane, and the horizontal teeth-to-lip relation was simplified and represented by the distances from dental landmarks to lower bow-shaped curves (LBSC), with the distance from facial-axis (FA) point of the canine to LBSC (FA-tangent line [TL] distance) identified as the key parameter. Using photographic modification and esthetic assessment, the effect of FA-TL distances on the attractiveness of 45° angled smiles was tested, with esthetic ranges identified. A simplified method was developed to obtain the estimative LBSC and FA-TL distances using 2-dimensional photographs and geometric analysis to facilitate clinical application. RESULTS: The FA-TL distance remarkably affected the esthetics of 45° angled smiles. Smiles were attractive when the FA-TL distance ranged from -1.0 to 1.5 mm perceived by orthodontists and from -1.5 to 1.5 mm perceived by laypersons. The 2-dimensional photograph-derived estimative FA-TL distance was not significantly different from that obtained in a 3-dimensional image, validating the simplified method. CONCLUSIONS: The LBSC could serve as a reference frame to determine the lateral limit of the maxillary anterior arch for the esthetics of 45° angled smiles. The FA-TL distance, which represented the spatial relation of the maxillary canine with the lower lip, was an esthetically essential parameter. For females aged 20-30 years, the FA point of the maxillary canines should be positioned no more than 1.5 mm labial or lingual to the LBSC.


Assuntos
Estética Dentária , Incisivo , Atitude do Pessoal de Saúde , Feminino , Humanos , Maxila , Ortodontistas , Sorriso
6.
J Exp Bot ; 71(18): 5469-5483, 2020 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-32474603

RESUMO

The function of the transcription factor KNOTTED ARABIDOPSIS THALIANA7 (KNAT7) is still unclear since it appears to be either a negative or a positive regulator for secondary cell wall deposition with its loss-of-function mutant displaying thicker interfascicular and xylary fiber cell walls but thinner vessel cell walls in inflorescence stems. To explore the exact function of KNAT7, class II KNOTTED1-LIKE HOMEOBOX (KNOX II) genes in Arabidopsis including KNAT3, KNAT4, and KNAT5 were studied together. By chimeric repressor technology, we found that both KNAT3 and KNAT7 repressors exhibited a similar dwarf phenotype. Both KNAT3 and KNAT7 genes were expressed in the inflorescence stems and the knat3 knat7 double mutant exhibited a dwarf phenotype similar to the repressor lines. A stem cross-section of knat3 knat7 displayed an enhanced irregular xylem phenotype as compared with the single mutants, and its cell wall thickness in xylem vessels and interfascicular fibers was significantly reduced. Analysis of cell wall chemical composition revealed that syringyl lignin was significantly decreased while guaiacyl lignin was increased in the knat3 knat7 double mutant. Coincidently, the knat3 knat7 transcriptome showed that most lignin pathway genes were activated, whereas the syringyl lignin-related gene Ferulate 5-Hydroxylase (F5H) was down-regulated. Protein interaction analysis revealed that KNAT3 and KNAT7 can form a heterodimer, and KNAT3, but not KNAT7, can interact with the key secondary cell wall formation transcription factors NST1/2, which suggests that the KNAT3-NST1/2 heterodimer complex regulates F5H to promote syringyl lignin synthesis. These results indicate that KNAT3 and KNAT7 synergistically work together to promote secondary cell wall biosynthesis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Lignina , Proteínas Nucleares , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genética
7.
Environ Technol ; 35(5-8): 993-1002, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24645483

RESUMO

Foam flushing is an in situ soil remediation technology based on the traditional surfactant flushing method. The mobility control by introduction of foam is helpful in improving this technology. In this study, foam flushing ofpolychlorinatedbiphenyl (PCB)-contaminated media was performed to evaluate the effect of foam mobility on PCB removal. The conductivity and sweep efficiency (SE) of foam with different Triton X-100 concentrations and gas contents through two sands (with permeability of 15 darcy and 120 darcy) were tested. The results indicate that the presence of foam can not only reduce the mobility and increase the SE values of washing agent in single media, but can also reduce the discrepancy of fluid mobility and SE values between different sands, primarily due to the additional capillary resistance arising from the Jamin effect. The increases of PCB removal by foam agreed with the increases of SE values: foam (5.00 g/L) flushing increased the PCB removal from 79.4% by solution flushing to 85.1% for coarse sand, and increased the value from 64.2% to 79.1% for fine sand. When surfactant concentration and gas-liquid ratio vary, the variation of PCB removal showed the same trend with the change of SE, and an opposite trend with the change of foam mobility. High concentration of surfactant (5.00 g/L) and a foam quality of 97.0% are most favourable for the reduction of foam mobility. On the other hand, the negative effect of foam caused by the reduction of effective cross-section will reduce the foam remediation efficiency, especially under a low Triton X-100 concentration condition.


Assuntos
Bifenilos Policlorados/química , Poluentes do Solo/química , Solo , Biodegradação Ambiental , Poluição Ambiental , Desenho de Equipamento , Gases , Teste de Materiais , Nitrogênio/química , Octoxinol , Tamanho da Partícula , Permeabilidade , Dióxido de Silício , Tensoativos/química , Temperatura
8.
J Air Waste Manag Assoc ; 63(1): 80-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23447866

RESUMO

UNLABELLED: The use of surfactants during soil washing process can create massive foam, which has a negative impact on the effective use of equipment. A series of tests was conducted to evaluate the defoaming performance of three defoamers and to investigate the influence on removal of polycyclic aromatic hydrocarbons (PAHs) during enhanced soil washing by the addition of the defoamer. Results showed that polydimethylsiloxane oil, which is the most common biomaterial used in commercial antifoaming and defoaming agents, has the best defoaming performance. With the addition of 0.1% polydimethylsiloxane oil, the removal ratios of total 16 PAHs (SigmaPAHs) increased up to 53.48% and 75.92% when washing time was 5 min and 30 min, respectively, compared with the removal ratios of 44.12% and 67.28% with Triton X-100 solution only. This indicated that the proper selection of defoamer not only solves massive foaming problem but also brings out a positive influence on PAH removal during the soil washing process. IMPLICATIONS: Three kinds of defoamers (kieselguhr, dodecanol, and polydimethylsiloxane oil) were collected to destroy the foam produced by Triton X-100. Among those defoamers, the polydimethylsiloxane (PDMS) oil has the best defoaming performances. The surface tension of the Triton X-100 solution with the addition of PDMS was lower. The addition of PDMS could improve the removal ratio of SigmaPAHs during soil washing. That may be attributed to the addition of the nonionic surfactant Tergitol NP-10 as the emulsifier in the defoamer. After all, the results do not provide any indication of the influence on the solubilization micelles. It is thus questionable whether other components of PDMS oil could improve the PAH solubilization.


Assuntos
Antiespumantes/química , Dimetilpolisiloxanos/química , Hidrocarbonetos Policíclicos Aromáticos/química , Poluentes do Solo/química , Recuperação e Remediação Ambiental , Tensão Superficial
9.
Water Sci Technol ; 68(10): 2294-300, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24292481

RESUMO

The adsorption behavior of phenanthrene (PHE) in Triton X-100 (TX100) solutions with fixed activated carbon (AC) bed was studied to recover the surfactant. The effect of various parameters like bed depths, flow rates, influent TX100 concentration, and influent PHE concentration were investigated. The breakthrough time of both TX100 and PHE increased with the increase of bed height and decrease of flow rate and influent concentration. In the case of fixed length, a lower flow rate, higher concentration of TX100, and lower concentration of PHE will benefit the longer effective surfactant recovery time. The adsorption data were integrated into bed depth service time models. The height of exchange zone of TX100 should be much shorter than that of PHE, which provides conditions to separate the hydrophobic organic compound from surfactant solutions with AC in a fixed bed. It is likely that the adsorption process is controlled by hydrophobic interaction.


Assuntos
Octoxinol/química , Fenantrenos/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Adsorção , Carvão Vegetal/química , Interações Hidrofóbicas e Hidrofílicas
10.
ACS Appl Mater Interfaces ; 13(13): 15621-15632, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33780233

RESUMO

Latent blood fingerprints (LBFPs) can provide critical information of foul play and help identify the suspects at violent crime scenes. The current methods for LBFP visualization are still not satisfactory because of the low sensitivity or complicated protocol. This study demonstrates a simple and effective LBFP visualization strategy by integrating a new amphiphilic fluorescent amino-functionalized conjugated polymer with the cotton-pad developing protocol. LBFPs on various substrates are visualized by simply covering them with the polymer solution-soaked cotton pads. The images display clear fingerprint patterns, ridge details, and sweat pores, even on very challenging substrates such as painted wood and multicolored can. The gray value analysis confirms semiquantitatively the enhancement of the contrast between ridges and furrows. Even LBFPs with various contaminations or aged for more than 600 days are effectively developed and visualized. The developed fingerprint images show superior stability over long storage time and against solvent washing. Moreover, the polymer causes no degradation of DNAs in the blood, suggesting the possibility of further DNA profiling and identification after development. The mechanistic investigation suggests that the formation of positive or inverted images can be attributed to the synergistic effects from the affinity between polymer and blood, and the affinity betwen polymer and substrate, as well as the slight quenching of polymer fluorescence by blood. Furthermore, the covalent bonding between the protonated primary amino group and proteins in blood endows the stability of the developed fingerprints. The result rationalizes the molecular design of the fluorescent polymer and sheds new light on the future strategies to effective LBFP visualization in practical applications.


Assuntos
Proteínas Sanguíneas/análise , Dermatoglifia , Corantes Fluorescentes/química , Manchas de Sangue , Ciências Forenses , Humanos , Imagem Óptica/métodos , Polímeros/química
11.
Mar Pollut Bull ; 164: 112000, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33515819

RESUMO

Microplastics as a new class of environmental contaminants have become the hot issue of global concern. We conducted quantitative and qualitative experiments to investigate microplastics in oyster, seawater and sediment along the Zhuhai coastline. The soft tissues of oysters were digested with potassium hydroxide (10%) and hydrogen peroxide (30%), seawaters and sediments with hydrogen peroxide (30%) to degrade organic matter, and analyzed using a digital camera, optical microscopy and micro-ATR-FTIR. The abundance of microplastics were in the range of 0.14-7.90 n/g in oysters (wet weight), 10.00-27.50 n/L in seawaters and 0.053-0.26 n/g in sediments. The fiber and fragment shape, black color, 101-500 µm of size and polyethylene composition were all classified as the major constituents of microplastics. The level of contaminants in oysters was correlated to those in their surrounding environments. Therefore, oysters may serve as a promising sentinel species for the indication of microplastic pollution in the coastal zone of Zhuhai.


Assuntos
Ostreidae , Poluentes Químicos da Água , Animais , China , Monitoramento Ambiental , Sedimentos Geológicos , Microplásticos , Plásticos , Água do Mar , Poluentes Químicos da Água/análise
12.
Front Neurol ; 10: 413, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31068899

RESUMO

X-linked Charcot-Marie-Tooth disease type 1 (CMTX1) is a dominantly inherited peripheral neuropathy and is caused by mutations in gap junction beta 1 gene (GJB1). Here, a novel variant of c.-170T>G in GJB1 was identified in a large Chinese CMTX1 pedigree. The proband presented transient "stroke-like" episodes in addition to the peripheral neuropathy. At the time of episode, he had transient hyperthyroidism. To our knowledge, this is the first variant found in non-coding region associated with transient central nervous system (CNS) symptoms and in this case, thyroid dysfunction might contribute to the episode. The mechanism of CMTX1 as well as the transient CNS symptoms waits to be elucidated.

13.
Zhonghua Wai Ke Za Zhi ; 45(16): 1128-31, 2007 Aug 15.
Artigo em Zh | MEDLINE | ID: mdl-18005619

RESUMO

OBJECTIVE: To observe the mechanical properties of decellularized porcine aortic valve, and to explore the effects of precoating methods of biological scaffold on histocompatibility. METHODS: Fresh porcine aortic valves were decellularized using trypsin, TritonX-100 and nuclease. Treated valves were evaluated by light microscopy, scanning electron microscopy (SEM) and mechanical test. Three groups of scaffold were precoated with phosphate buffered saline (PBS), poly-L-lysine (PLL) and fetal bovine serum (FBS) respectively. Myofibroblasts were seeded onto each scaffold. Light and electron microscopic observation was performed and MTT test was used to examine efficiency of cell attachment. RESULTS: HE stain and SEM showed that cells were almost absent in the treated leaflet. The wave-like collagen together with the whole three-dimensional structure was maintained. Compared with normal valves, the Max-load, Max-stress and elastic modulus decreased while the Max-strain increased (P<0.05). The result of MTT test showed more cells were attached on the valves treated with FBS compared to the other two groups. Histological investigations also confirm that the high degree of cell attachment on the valves precoated with FBS (F=129.26, P=0.000). CONCLUSIONS: Enzyme combined with detergent and nucleases can remove cells from porcine aortic valves. Meanwhile the mechanical properties of these valves may be altered. Precoating porcine aortic valve with FBS is an effective method to improve cell attachment, growth and increasing.


Assuntos
Valva Aórtica/fisiologia , Materiais Revestidos Biocompatíveis/química , Alicerces Teciduais/química , Animais , Valva Aórtica/citologia , Valva Aórtica/efeitos dos fármacos , Fenômenos Biomecânicos , Bioprótese , Adesão Celular , Proliferação de Células , Células Cultivadas , Materiais Revestidos Biocompatíveis/farmacologia , Fibroblastos/citologia , Próteses Valvulares Cardíacas , Ratos , Suínos , Engenharia Tecidual/métodos
14.
Environ Sci Pollut Res Int ; 24(26): 21011-21023, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28726225

RESUMO

Viscosity remedial technology, which uses a water-soluble polymer mixed with remedial fluids, has been introduced in recent years to improve the removal efficacy of perchloroethylene/tetrachloroethylene (PCE) by improving oxidant coverage (i.e. sweep efficiency). Xanthan gum and hydrolysed polyacrylamide (HPAM) are relatively stable with time and temperature and possess salt and oxidation resistance, indicating that they may be good flooding agents (the former is better than the latter in this work). In this work, we quantified the polymer directly improved oxidation of PCE during transport by using a two-dimensional flow tank. Using a low pore volume (≤3.0), the removal rate of the PCE increased with the polymer concentration before stabilizing at approximately 93.00 and 88.30% for xanthan and HPAM, respectively. In this work, over 80% of PCE was removed via less than 3.0 PV of the SDS solution, whereas complete removal (100%) was achieved with less than 3.0 PV of SDS foam. Furthermore, the new experimental discoveries demonstrate that xanthan is better than HPAM and SDS foam is a better remediation agent than the SDS solution for removing PCE. Graphical abstract (Reaction device, A - inlet device (pump 1#), B - 2D tank, C - outflow device (pump 2#), D - data recording and processing device, E - microscopic expression, E (a) - KMnO4 flushing, E (b) - polymer solution flushing).


Assuntos
Recuperação e Remediação Ambiental/métodos , Oxidantes/química , Tetracloroetileno/química , Resinas Acrílicas/química , Oxirredução , Polímeros/química , Polissacarídeos Bacterianos/química , Dodecilsulfato de Sódio/química , Viscosidade
15.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 31(10): 1231-1235, 2017 10 15.
Artigo em Zh | MEDLINE | ID: mdl-29806326

RESUMO

Objective: To evaluate the biomechanical stability of a newly-designed Y type pedicle screw (YPS) in osteoporotic synthetic bone. Methods: The osteoporotic synthetic bone were randomly divided into 3 groups ( n=20). A pilot hole, 3.0 mm in diameter and 30.0 mm in deep, was prepared in these bones with the same method. The YPS, expansive pedicle screw (EPS), and bone cement-injectable cannulated pedicle screw (CICPS) were inserted into these synthetic bone through the pilot hole prepared. X-ray film examination was performed after 12 hours; the biomechanical stability of YPS, EPS, and CICPS groups was tested by the universal testing machine (E10000). The test items included the maximum axial pullout force, the maximum running torque, and the maximum periodical anti-bending. Results: X-ray examination showed that in YPS group, the main screw and the core pin were wrapped around the polyurethane material, the core pin was formed from the lower 1/3 of the main screw and formed an angle of 15° with the main screw, and the lowest point of the inserted middle core pin was positioned at the same level with the main screw; in EPS group, the tip of EPS expanded markedly and formed a claw-like structure; in CICPS group, the bone cement was mainly distributed in the front of the screw and was dispersed in the trabecular bone to form a stable screw-bone cement-trabecular complex. The maximum axial pullout force of YPS, EPS, and CICPS groups was (98.43±8.26), (77.41±11.41), and (186.43±23.23) N, respectively; the maximum running torque was (1.42±0.33), (0.96±0.37), and (2.27±0.39) N/m, respectively; and the maximum periodical anti-bending was (67.49±3.02), (66.03±2.88), and (143.48±4.73) N, respectively. The above indexes in CICPS group were significantly higher than those in YPS group and EPS group ( P<0.05); the maximum axial pullout force and the maximum running torque in YPS group were significantly higher than those in EPS group ( P<0.05), but there was no significant difference in the maximum periodical anti-bending between YPS group and EPS group ( P>0.05). Conclusion: Compared with EPS, YPS can effectively enhance the maximum axial pullout force and maximum rotation force in the module, which provides a new idea for the design of screws and the choice of different fixation methods under the condition of osteoporosis.


Assuntos
Cimentos Ósseos , Osteoporose/terapia , Parafusos Pediculares , Polimetil Metacrilato , Fenômenos Biomecânicos , Fixação de Fratura , Humanos , Vértebras Lombares , Distribuição Aleatória
16.
Environ Sci Pollut Res Int ; 22(4): 2994-3003, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25226831

RESUMO

With an aim to select the most appropriate foaming surfactant for remediation of DDT-contaminated soil by foam-flushing technique, the performances of nonionic and anionic surfactant in several aspects were observed in this study. SDS had the best foam static characteristic among the four experimental surfactants. The solubilizing ability for DDT followed the order of Tween80 > TX100 > SDS > Brij35. The adsorption loss of SDS onto soil was the lowest. The order of desorption efficiency for DDT followed as TX-100 > Tween80 > Brij35 > SDS. Based on these experimental investigations, the overall performances of foaming surfactants were evaluated by data envelopment analysis method. The results indicated that SDS was the optimal alternative for remediation of DDT-contaminated soil by foam-flushing technique. This conclusion was reached with the consideration of the cost, foam static characteristic, surfactant adsorption loss, solubilizing ability, and desorption efficiency of surfactant for DDT.


Assuntos
DDT/análise , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/química , Tensoativos/farmacologia , Adsorção , Cromatografia Gasosa-Espectrometria de Massas , Tamanho da Partícula , Polietilenoglicóis/farmacologia , Polissorbatos/farmacologia , Dodecilsulfato de Sódio/farmacologia , Solubilidade
17.
Inflammation ; 38(3): 978-86, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25384562

RESUMO

The objective of this study was to investigate the expression level, clinical significance, and possible regulating role of IL-17F in patients of chronic periodontitis. Periodontal local tissues were obtained from chronic periodontitis (CP) and healthy controls (HC) for real-time PCR (RT-PCR) detection with IL-17F and IL-17A messenger RNA (mRNA). Primary human gingival fibroblasts (HGF) were derived from patients receiving crown-lengthening procedures. Efficiency of small interfering RNA (siRNA) of IL-17R to HGF cells were assessed by Western blot and RT-PCR. Recombinant IL-17F and IL-17A were used to stimulate the HGF cells compared with the control group. Aspects of the nuclear factor-kappa B (NF-κB) and extracellular signal-regulated kinase (ERK) signaling pathways were examined by Western blot. Production of pro-inflammatory cytokines induced by IL-17F and IL-17A was detected by RT-PCR. Statistical analysis was analyzed by SPSS software. It showed significantly elevated levels of IL-17F and IL-17A mRNA in CP gingival tissues compared with HC group (P<0.01). Further analysis showed a significant correlation between IL-17F and IL-17A mRNA in CP group (P<0.05), and both cytokines also correlated with the probing depth (P<0.05). Recombinant IL-17F can induce NF-κB phosphor-p65 and ERK phosphorylation of HGF cells similar to that of IL-17A. Interestingly, we found that both IL-17F and IL-17A could promote the important inflammatory cytokines IL-6, CXCL8, and CCL20 production compared with IL-17R siRNA group (P<0.05). This study indicates that IL-17F may be involved in pathogenesis of periodontitis like IL-17A. The role of IL-17F in disease pathogenesis needs to be further investigated.


Assuntos
Periodontite Crônica/patologia , Gengiva/patologia , Interleucina-17/metabolismo , Adulto , Células Cultivadas , Quimiocina CCL20/biossíntese , Periodontite Crônica/imunologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Fibroblastos , Gengiva/citologia , Humanos , Interleucina-17/genética , Interleucina-6/biossíntese , Interleucina-8/biossíntese , Masculino , Fosforilação , Interferência de RNA , RNA Mensageiro/genética , RNA Interferente Pequeno , Receptores de Interleucina-17/genética , Proteínas Recombinantes/farmacologia , Transdução de Sinais , Fator de Transcrição RelA/metabolismo
18.
Environ Sci Pollut Res Int ; 21(3): 1809-1818, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23979852

RESUMO

Adsorption of fluoranthene (FLA) in surfactant solution on activated carbon (AC) was investigated. Isotherm, thermodynamic, and kinetic attributes of FLA adsorption in the presence of the surfactant on AC were studied. Effects of AC dosage, initial concentration of TX100, initial concentration of FLA, and addition of fulvic acid on adsorption were studied. The experimental data of both TX100 and FLA fitted the Langmuir isotherm model and the pseudo-second-order kinetic model well. Positive enthalpy showed that adsorption of FLA on AC was endothermic. The efficiency of selective FLA removal generally increased with increasing initial surfactant concentration and decreasing fulvic acid concentration. The surface chemistry of AC may determine the removal of polycyclic aromatic hydrocarbons. The adsorption process may be controlled by the hydrophobic interaction between AC and the adsorbate. The microwave irradiation of AC may be a feasible method to reduce the cost of AC through its regeneration.


Assuntos
Carvão Vegetal/química , Fluorenos/química , Poluentes do Solo/química , Tensoativos/química , Adsorção , Fluorenos/análise , Interações Hidrofóbicas e Hidrofílicas , Cinética , Octoxinol/química , Poluentes do Solo/análise , Termodinâmica
19.
Biomed Mater Eng ; 24(6): 2089-99, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25226906

RESUMO

This study aimed to establish a novel non-viral liposome vector delivering brain derived neurotrophic factor (BDNF) through the blood brain barrier. For this purpose, different water-oil ratios were tested to create liposomes for packaging the prophase synthesized plasmids encoding the BDNF proteins. In order to increase the targeted and peripheral circulation time, we connected the liposomes with transferrin (Tf) and a polyethylene glycol (PEG) long chain. The non-isotope method was used to measure the liposome envelopment ratio and ligand-binding ratio, and also to detect molecular biological features, such as particle size and stability. Tf-conjugated liposomes could be synthesized satisfactorily under the following conditions: the ratio of phospholipid to cholesterol was 1:1; the ratio of enter to plasmid was 100:1; oil phase was dichloromethane; the oil to water ratio was 4:1; the rotary evaporation temperature was 30 °C; the ultrasonic temperature was 10 °C; the ultrasonic time was 10 min; and 10% trehalose was in the presence. Generated liposomes had a uniform circular shape and particle size distribution. In this experiment, we successfully established a new type of Tf-conjugated liposomes carrying the gene of BDNF and the study provides an experimental basis for the future.


Assuntos
Barreira Hematoencefálica/metabolismo , Fator Neurotrófico Derivado do Encéfalo/química , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Lipossomos/síntese química , Plasmídeos/administração & dosagem , Transfecção/métodos , Transferrina/farmacocinética , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Composição de Medicamentos/métodos , Desenho de Fármacos , Humanos , Teste de Materiais , Plasmídeos/genética
20.
Recent Pat Nanotechnol ; 7(1): 2-12, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22747718

RESUMO

Nanostructured materials afford us new opportunities to improve the current technology for synthesizing Li ion batteries. Generating nanomaterials with new properties via an inexpensive approach offers a tremendous potential for realizing high performance Li-ion batteries. In this review, I mainly summarize some of the recent progress made, and describe the patents awarded on synthesizing nanostructured cathode materials for these batteries via low temperature wet- chemistry methods. From an economical view, such syntheses, especially hydrothermal synthesis, may offer the opportunities for significantly lowering the cost of manufacturing battery materials, while conferring distinct environmental advantages. Recent advances in in-situ (real time) X-ray diffraction for studying hydrothermal synthesis have great potential for bettering the rational design of advanced lithium-electrode materials. The development of this technique also will be discussed.


Assuntos
Fontes de Energia Elétrica , Lítio/química , Nanoestruturas/química , Íons/química , Compostos de Ferro/química , Compostos de Magnésio/química , Nanoestruturas/ultraestrutura , Patentes como Assunto , Polímeros/química , Silicatos/química , Temperatura
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