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1.
Lasers Med Sci ; 38(1): 184, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37578665

RESUMO

The aim of this study is to systematically summarize the available evidence regarding low-level laser therapy (LLLT) speed-up effect on dental alignment in comprehensive orthodontic treatment. An extensive electronic search was conducted in PubMed, ScienceDirect, Cochrane, Web of Science, and Scopus up to February 20, 2023. The Cochrane risk of bias tool and the Newcastle-Ottawa Quality Assessment Form were used by two authors independently to assess the risk of bias (RoB). Statistical analysis was performed by Review Manager 5.3. The eight eligible trials were reviewed and included in qualitative synthesis. Four studies reported the overall time of leveling and alignment (OLAT, days), enabling a synthesizing of the data. The meta-analysis results showed that LLLT significantly reduced the overall time of leveling and alignment compared to control group (MD=-30.36, 95% CI range -41.50 to -19.22, P<0.0001), with moderate heterogeneity (χ2=4.10, P=0.25, I2=27%). Based on the data available, statistically significant evidence with moderate risk of bias suggests that LLLT may have a positive effect on accelerating dental alignment. However, due to the differences in intervention strategy and evaluating method, the conclusions should be interpreted with caution.


Assuntos
Terapia com Luz de Baixa Intensidade , Técnicas de Movimentação Dentária , Fatores de Tempo , Técnicas de Movimentação Dentária/métodos
2.
Sensors (Basel) ; 23(22)2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-38005522

RESUMO

Three-dimensional laser scanning has emerged as a prevalent measurement method in numerous high-precision applications, and the precision of the obtained data is closely related to the intensity information. Comprehending the association between intensity and point cloud accuracy facilitates scanner performance assessment, optimization of data acquisition strategies, and evaluation of point cloud precision, thereby ensuring data reliability for high-precision applications. In this study, we investigated the correlation between point cloud accuracy and two distinct types of intensity information. In addition, we presented methods for assessing point cloud accuracy using these two forms of intensity information, along with their applicable scopes. By examining the percentage intensity, we analyzed the reflectance properties of the scanned object's surface employing the Lambertian model. Our findings indicate that the Lambertian circle fitting radius is inversely correlated with the scanner's ranging error at a constant scanning distance. Experimental outcomes substantiate that modifying the surface characteristics of the object enables the attainment of higher-precision point cloud data. By constructing a model associating the raw reflectance intensity with ranging errors, we developed a single-point error ellipsoid model to assess the accuracy of individual points within the point cloud. The experiments revealed that the ranging error model based on the raw intensity is solely applicable to point cloud data unaffected by specular reflectance properties. Moreover, the devised single-point error ellipsoid model accurately evaluates the measurement error of individual points. Both analytical methods can be utilized to evaluate the performance of the scanner as well as the accuracy of the acquired point cloud data, providing reliable data support for various high-precision applications.

3.
Small ; 18(7): e2102397, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34862722

RESUMO

Smart supercapacitors are a promising energy storage solution due to their high power density, long cycle life, and low-maintenance requirements. Functional polymers (FPs) and inorganic nanomaterials are used in smart supercapacitors because of the favorable mechanical properties (flexibility and stretchability) of FPs and the energy storage properties of inorganic materials. The complementary properties of these materials facilitate commercial applications of smart supercapacitors in flexible smart wearables, displays, and self-generation, as well as energy storage. Here, an overview of strategies for the development of suitable materials for smart supercapacitors is presented, based on recent literature reports. A range of synthetic techniques are discussed and it is concluded that a combination of organic and inorganic hybrid materials is the best option for realizing smart supercapacitors. This perspective facilitates new strategies for the synthesis of hybrid materials, and the development of material technologies for smart energy storage applications.

4.
Inorg Chem ; 61(48): 19417-19424, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36403146

RESUMO

The development of actinide materials has provided new strategies for the utilization of nuclear waste, such as depleted uranium, a mildly radioactive waste in the nuclear power industry, which could be a precious resource for many fields, especially water splitting. The catalytic performance of water splitting is limited by the slow kinetics of the oxygen evolution reaction (OER), and it is extremely challenging to design efficient OER catalysts that are highly stable and inexpensive. Here, we design and describe a series of U5-35%-Co3O4 electrocatalysts, which were synthesized using uranyl nitrate as a precursor via a simple and scalable method. Interestingly, when the U/Co molar ratio was 20%, a UCoO4/Co3O4 heterojunction formed with high catalytic efficiency and excellent long-term electrolytic stability. The UCoO4/Co3O4 heterojunction catalyst shows a lower overpotential (280 mV) at a current density of 10 mA cm-2, and the slope of Tafel is 43.8 mV decade-1 in a 0.1 M KOH alkaline solution. Soft X-ray absorption spectroscopy shows that the cooperative effect of UCoO4 and Co3O4 can improve the electrochemical activity of the material. This study produced an active U/Co-based catalyst for OER, which provides a simple, scalable, low-cost, and highly efficient catalyst for overall water splitting.

5.
Sensors (Basel) ; 22(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36501989

RESUMO

As the technology of high-precision 3D laser scanning becomes increasingly prevalent in the fields of hydraulic building modeling and deformation monitoring, the quality of point clouds plays an increasingly crucial role in data processing. This paper investigates an automatic extraction method of anchor rod points based on geometric features, which focuses on the influence of anchor rod points and mixed pixels in the data of an underground powerhouse of a pumped storage power station on modeling and deformation monitoring during the construction period. This workflow consists of two steps that can automatically extract anchor rod points from high-density point cloud data. Triangular mesh features in the local neighborhood and the parameters of the anchor rods are used to locate the anchor rod in downsampled data, and curvature features are used to extract anchor rod points precisely. The experiment of extracting anchor rods shows that the accuracy of this method of initial identification is 97.2%. Furthermore, precise extraction based on curvature curve fitting is applicable. This method can accurately separate the three types of anchor rods from the dense point cloud on the rough surface of a cavern roof; the false-extraction rate of anchor rod points is about 0.11% to 5.09%. This method can provide high-quality and dependable data sources for the precise registration, modeling and deformation analysis of point clouds in a construction cavern.

6.
Chemistry ; 27(42): 10998-11004, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-33909301

RESUMO

Fe0.95 S1.05 with high reactivity and stability was incorporated into WS2 nanosheets via a one-step solvothermal method for the first time. The resulted hybrid catalyst has much higher catalytic activity than WS2 and Fe0.95 S1.05 alone, and the optimal WS2 /Fe0.95 S1.05 hybrid catalyst was found by adjusting the feed ratio. The addition of Fe0.95 S1.05 was proven to be able to enhance the hydrogen evolution reaction (HER) activity of WS2 , and vice versa. At the same time, it was found that the catalytic effect of the hybrid catalyst was the best when the feed ratio was W : Fe=2 : 1. In other words, we confirmed that there is a synergistic effect between W- and Fe-based sulfide hybrid catalysts, and validated that the reason for the improved HER performance is the strong interaction between the two in the middle sulfur. WS2 /Fe0.95 S1.05 -2 hybrid catalyst leads to enhanced HER activity, which shows a low overpotential of ∼0.172 V at 10 mA cm-2 , low Tafel slope of ∼53.47 mV/decade. This study supplies innovative synthesis of a highly active WS2 /Fe0.95 S1.05 hybrid catalyst for HER.

7.
Med Sci Monit ; 26: e922372, 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32323648

RESUMO

BACKGROUND This study was performed to investigate the effect of local injection of asperosaponin VI (ASA VI) on the orthodontic tooth movement in rats. MATERIAL AND METHODS A total of 64 healthy female Sprague-Dawley rats were selected and divided into 2 groups randomly: the ASA VI group and the control group. For the ASA VI group, 10 mg/kg ASA VI solution was injected into buccal submucoperiosteal of bilaterally first maxillary molars, and the same volume of normal saline was given to the control group. The orthodontic force was applied to the maxillary first molars. All rats were sacrificed on days 3, 7, or 14. Tooth movement effects on the periodontium were analyzed through hematoxylin and eosin (H&E) staining, tartrate-resistant acid phosphatase (TRAP) staining and immunohistochemistry analysis. Tooth movement measurements and alveolar bone volumetric changes were analyzed using a micro-computed tomography (CT) scan. Molecular changes were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. RESULTS The ASA VI group presented with a significant increase of tooth movement, osteoclast number, and the expression of osteoclast differentiation factor (ODF) compared with the control group. ASA VI also induced a significant decrease in bone volume and density and an increase in trabecular spacing and RANKL (receptor activator of nuclear factor kappa-B ligand) expression at the compression side. Furthermore, ASA VI stimulated bone formation on the tension side by enhancing OCN (osteocalcin) expression and RUNX2 (runt-related transcription factor 2) expression, increasing bone volume and density and decreasing in trabecular spacing. CONCLUSIONS Injection of ASA VI may accelerate tooth movement via increasing the activity of osteoclasts, stimulating bone resorption at the compression side. Furthermore, ASA VI has a positive effect on bone formation at the tension side.


Assuntos
Remodelação Óssea/efeitos dos fármacos , Saponinas/farmacologia , Técnicas de Movimentação Dentária/métodos , Processo Alveolar/efeitos dos fármacos , Animais , Reabsorção Óssea/metabolismo , China , Feminino , Dente Molar/efeitos dos fármacos , Dente Molar/metabolismo , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Reabsorção da Raiz , Saponinas/metabolismo
8.
Sensors (Basel) ; 20(6)2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32204314

RESUMO

The Internet of Things (IoT) is widely applied in modern human life, e.g., smart home and intelligent transportation. However, it is vulnerable to malicious attacks, and the current existing security mechanisms cannot completely protect the IoT. As a security technology, intrusion detection can defend IoT devices from most malicious attacks. However, unfortunately the traditional intrusion detection models have defects in terms of time efficiency and detection efficiency. Therefore, in this paper, we propose an improved linear discriminant analysis (LDA)-based extreme learning machine (ELM) classification for the intrusion detection algorithm (ILECA). First, we improve the linear discriminant analysis (LDA) and then use it to reduce the feature dimensions. Moreover, we use a single hidden layer neural network extreme learning machine (ELM) algorithm to classify the dimensionality-reduced data. Considering the high requirement of IoT devices for detection efficiency, our scheme not only ensures the accuracy of intrusion detection, but also improves the execution efficiency, which can quickly identify the intrusion. Finally, we conduct experiments on the NSL-KDD dataset. The evaluation results show that the proposed ILECA has good generalization and real-time characteristics, and the detection accuracy is up to 92.35%, which is better than other typical algorithms.


Assuntos
Segurança Computacional , Internet das Coisas , Aprendizado de Máquina , Redes Neurais de Computação , Algoritmos , Análise Discriminante , Humanos
9.
Inorg Chem ; 55(2): 411-8, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26230977

RESUMO

A series of pendant amine-containing [FeFe]-hydrogenase models, [X(CH2S-µ)2{Fe(CO)3}{Fe(CO)(P2(Ph)N2(Bn))}] (1H, X = CH2; 2Me, C(CH3)2; 3Et, C(CH2CH3)2; and P2(Ph)N2(Bn) = 1,5-dibenzyl-3,7-diphenyl-1,5-diaza-3,7-diphosphacyclooctane) with different groups at the bridgehead carbon of the S-to-S linker were synthesized. The oxidations of these complexes as well as the reverse reduction reaction were studied by cyclic voltammetry and in situ IR spectroscopy. Regardless of the bridgehead steric bulk, all three complexes demonstrate intramolecular iron-mediated C(sp(3))-H bond heterolytic cleavage with the assistance of the pendant amine base within the chelating diphosphine ligand in the two-electron oxidation process. X-ray crystallographic analysis shows that the doubly oxidized products, [1'H](+), [2'Me](+), and [3'Et](+), all have a rigid FeSC three-membered ring at the open apical site of the rotated iron center. The most noticeable difference in structures of the oxidized complexes is that the single CO ligand of the rotated Fe(P2(Ph)N2(Bn))(CO) unit in [1'H](+) and [2'Me](+) is found below the Fe···Fe vector, while in [3'Et](+) an unusually rotated Fe(P2(Ph)N2(Bn))(CO) moiety positions one of the P donors within the bidentate ligand under the Fe···Fe vector. The starting Fe(I)Fe(I) complexes can be recovered from their corresponding doubly oxidized complexes by reduction in the presence of Brönsted acid.


Assuntos
Aminas/química , Carbono/química , Hidrogênio/química , Hidrogenase/química , Proteínas Ferro-Enxofre/química , Domínio Catalítico , Cristalografia por Raios X , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares
10.
BMC Oral Health ; 15: 148, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26589825

RESUMO

BACKGROUND: The objectives of this study were to investigated changes in OHRQoL among patients with different classifications of malocclusion during comprehensive orthodontic treatment. METHODS: Clinical data were collected from 81 patients (aged 15 to 24) who had undergone comprehensive orthodontic treatment. Participants were classified 3 groups: Class I (n = 35), II (n = 32) and III (n = 14) by Angle classification. OHRQoL was assessed using the Oral Health Impact Profile (OHIP-14). All subjects were examined and interviewed at baseline (T0), after alignment and leveling (T1), after correction of molar relationship and space closure (T2), after finishing (T3). Friedman 2-way analysis of variance (ANOVA) and Wilcoxon signed rank tests were used to compare the relative changes of OHRQoL among the different time points. A Bonferroni correction with P < 0.005 was used to declare significance. RESULTS: Significant reductions were observed in all seven OHIP-14 domains of three groups except for social disability (P > 0.005) in class I and class II, Handicap in class II and class III (P > 0.005). Class I patients showed significant changes for psychological disability and psychological discomfort domain at T1, functional limitation, physical pain at T2. Class III patients showed a significant benefit in all domains except physical pain and functional limitation. Class II patients showed significant changes in the physical pain, functional disability, and physical disability domains at T1. CONCLUSIONS: The impact of comprehensive orthodontic treatment on patients' OHRQoL do not follow the same pattern among patients with different malocclusion. Class II patients benefits the most from the stage of space closure, while class I patients benefits the first stage (alignment and leveling) of treatment in psychological disability and psychological discomfort domains.


Assuntos
Má Oclusão/psicologia , Saúde Bucal , Ortodontia Corretiva/psicologia , Qualidade de Vida , Atividades Cotidianas , Adolescente , Adulto , Assistência Odontológica Integral , Feminino , Seguimentos , Humanos , Masculino , Má Oclusão/terapia , Má Oclusão Classe I de Angle/psicologia , Má Oclusão Classe I de Angle/terapia , Má Oclusão Classe II de Angle/psicologia , Má Oclusão Classe II de Angle/terapia , Má Oclusão Classe III de Angle/psicologia , Má Oclusão Classe III de Angle/terapia , Fechamento de Espaço Ortodôntico/psicologia , Medição da Dor/métodos , Habilidades Sociais , Estresse Psicológico/psicologia , Técnicas de Movimentação Dentária/psicologia , Adulto Jovem
11.
J Am Chem Soc ; 136(48): 16817-23, 2014 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-25244613

RESUMO

Although many metalloenzymes containing iron play a prominent role in biological C-H activation processes, to date iron-mediated C(sp(3))-H heterolysis has not been reported for synthetic models of Fe/S-metalloenzymes. In contrast, ample precedent has established that nature's design for reversible hydrogen activation by the diiron hydrogenase ([FeFe]-H2ase) active site involves multiple irons, sulfur bridges, a redox switch, and a pendant amine base, in an intricate arrangement to perform H-H heterolytic cleavage. In response to whether this strategy might be extended to C-H activation, we report that a [FeFe]-H2ase model demonstrates iron-mediated intramolecular C-H heterolytic cleavage via an agostic C-H interaction, with proton removal by a nearby pendant amine, affording Fe(II)-[Fe'(II)-CH-S] three-membered-ring products, which can be reduced back to 1 by Cp2Co in the presence of HBF4. The function of the pendant base as a proton shuttle was confirmed by the crystal structures of the N-protonated intermediate and the final deprotonated product in comparison with that of a similar but pendant-amine-free complex that does not show evidence of C-H activation. The mechanism of the process was backed up by DFT calculations.


Assuntos
Hidrogenase/metabolismo , Compostos de Ferro/metabolismo , Proteínas Ferro-Enxofre/metabolismo , Hidrogenase/química , Compostos de Ferro/síntese química , Compostos de Ferro/química , Proteínas Ferro-Enxofre/química , Modelos Moleculares , Conformação Molecular , Oxirredução , Teoria Quântica
12.
Inorg Chem ; 53(3): 1555-61, 2014 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-24422466

RESUMO

A diiron dithiolate complex with a pendant phosphine coordinated to one of the iron centers, [(µ-SCH2)2N(CH2C6H4-o-PPh2){Fe2(CO)5}] (1), was prepared and structurally characterized. The pendant phosphine is dissociated together with a CO ligand in the presence of excess PMe3, to afford [(µ-SCH2)2N(CH2C6H4-o-PPh2){Fe(CO)2(PMe3)}2] (2). Redox reactions of 2 and related complexes were studied in detail by in situ IR spectroscopy. A series of new Fe(II)Fe(I) ([3](+) and [6](+)), Fe(II)Fe(II) ([4](2+)), and Fe(I)Fe(I) (5) complexes relevant to Hox, Hox(CO), and Hred states of the [FeFe]-hydrogenase active site were detected. Among these complexes, the molecular structures of the diferrous complex [4](2+) with the internal amine and the pendant phosphine co-coordinated to the same iron center and the triphosphine diiron complex 5 were determined by X-ray crystallography. To make a comparison, the redox reactions of an analogous complex, [(µ-SCH2)2N(CH2C6H5){Fe(CO)2(PMe3)}2] (7), were also investigated by in situ IR spectroscopy in the absence or presence of extrinsic PPh3, which has no influence on the oxidation reaction of 7. The pendant phosphine in the second coordination sphere makes the redox reaction of 2 different from that of its analogue 7.


Assuntos
Aminas/química , Compostos Férricos/química , Hidrogenase/química , Ferroproteínas não Heme/química , Fosfinas/química , Compostos de Sulfidrila/química , Monóxido de Carbono/química , Cristalografia por Raios X , Modelos Moleculares , Oxirredução
13.
J Am Chem Soc ; 135(37): 13688-91, 2013 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-24001095

RESUMO

A [FeFe]-hydrogenase model (1) containing a chelating diphosphine ligand with a pendant amine was readily oxidized by Fc(+) (Fc = Cp2Fe) to a Fe(II)Fe(I) complex ([1](+)), which was isolated at room temperature. The structure of [1](+) with a semibridging CO and a vacant apical site was determined by X-ray crystallography. Complex [1](+) catalytically activates H2 at 1 atm at 25 °C in the presence of excess Fc(+) and P(o-tol)3. More interestingly, the catalytic activity of [1](+) for H2 oxidation remains unchanged in the presence of ca. 2% CO. A computational study of the reaction mechanism showed that the most favorable activation free energy involves a rotation of the bridging CO to an apical position followed by activation of H2 with the help of the internal amine to give a bridging hydride intermediate.


Assuntos
Complexos de Coordenação/química , Hidrogênio/química , Hidrogenase/química , Proteínas Ferro-Enxofre/química , Modelos Moleculares , Catálise , Domínio Catalítico , Cristalografia por Raios X
14.
Inorg Chem ; 52(4): 1798-806, 2013 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-23368811

RESUMO

Two tetranuclear iron-sulfur complexes, (µ,µ-pbtt)[Fe(2)(CO)(6)](2) (pbtt = benzene-1,2,4,5-tetrathiolato, 3) and (µ,µ-obtt)[Fe(2)(CO)(6)](2) (obtt = benzene-1,2,3,4-tetrathiolato, 4), were prepared from reaction of Fe(3)(CO)(12) and the corresponding tetramercaptobenzene in THF, respectively. Complexes 5 and 6, (µ,µ-pbtt)[Fe(2)(CO)(5)L(1)][Fe(2)(CO)(5)L(2)] (L(1) = CO, L(2) = PPyr(3) (Pyr = N-pyrrolyl), 5; L(1) = L(2) = PPyr(3), 6) were obtained by controlling CO displacement of 3 with PPyr(3). Molecular structures of 3-6 were determined by spectroscopic and single-crystal X-ray analyses. All-CO Fe(4)S(4) complexes 3 and 4 each display four-electron reduction processes in consecutive chemically reversible two-electron reduction events with relatively narrow potential spans in the cyclic voltammograms. Phosphine-substituted Fe(4)S(4) complexes 5 and 6 exhibit two consecutive two-electron reduction events, which are not fully reversible. The electrocatalytic properties of 3 and 4 for proton reduction were studied using a series of carboxylic acids of increasing strength (CH(3)COOH, CH(2)ClCOOH, CHCl(2)COOH, CCl(3)COOH, and CF(3)COOH). The mechanisms for electrochemical proton reduction to hydrogen catalyzed by complex 3 as a function of acid strength are discussed.


Assuntos
Derivados de Benzeno/química , Técnicas Eletroquímicas , Compostos de Ferro/química , Prótons , Monóxido de Carbono/química , Catálise , Transporte de Elétrons , Compostos de Ferro/síntese química , Modelos Moleculares , Conformação Molecular , Oxirredução
15.
Mol Biol Rep ; 40(12): 6811-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24057258

RESUMO

The mixed-lineage leukemia (MLL)-AF4 fusion protein encoded by the chromosomal translocation t(4;11) predicts a poorer prognosis in acute lymphoblastic leukemia (ALL) than in other MLL-associated leukemias. However, the detailed mechanism underlying regulation of MLL-AF4 expression remains largely unknown. In this study, we showed that microRNA (miR)-142-3p was significantly downregulated in ALL patients expressing MLL-AF4. Upregulation of miR-142-3p decreased MLL-AF4 expression in the RS4;11 leukemic cell line, which suggests that MLL-AF4 is a direct target of miR-142-3p. Ectopic expression of miR-142-3p remarkably suppressed cell proliferation and induced apoptosis in RS4;11 cells expressing the MLL-AF4 fusion protein. We also found that exogenous expression of miR-142-3p strongly reduced the expression of MLL-AF4 target genes such as homeobox A (HOXA)9, HOXA7, and HOXA10 in RS4;11 cells. Taken together, our results indicate that miR-142-3p functions as a growth suppressor in MLL-AF4(+) ALL, and its suppressive effects are mediated primarily through repression of MLL-AF4 expression.


Assuntos
MicroRNAs/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Fusão Oncogênica/genética , Oncogenes , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Adolescente , Adulto , Idoso , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo/genética , Feminino , Regulação Leucêmica da Expressão Gênica , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética , Adulto Jovem
16.
Eur J Med Res ; 28(1): 50, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707888

RESUMO

BACKGROUND: Miniscrews as auxiliary anchorage devices in orthodontic treatment have definite advantages and efficacy. The aim of the present study was to investigate the scientific evidence including randomized controlled trials (RCTs) or controlled clinical trials (CCTs) to support the application of low-level laser therapy to improve miniscrews stability in orthodontic treatment. METHODS: An extensive literature research was conducted with the Cochrane Library, PubMed, EMBASE, Web of Science and ScienceDirect without language limitations. All searches were inclusive until June 2020. The Cochrane Risk of Bias Tool was used to assess the risk of bias (RoB) in the included RCTs. RESULTS: Through the electronic searches, 428 titles and abstracts were identified. From these, 4 articles were retrieved for review, and 3 of these met the inclusion criteria. Two RCTs reported increased miniscrews stability with low-intensity laser therapy, but the other one reported no difference. Except one study assessed as "high risk of bias" the other two were rated as "low risk of bias". CONCLUSION: There is insufficient evidence to support or refute the effectiveness of LLLT for improvement of miniscrew stability. Further studies with a better study design, reliable evaluation method, comprehensive evaluation intervals and appropriate loading protocol are required to provide more reliable evidence for the clinical application of LLLT.


Assuntos
Terapia com Luz de Baixa Intensidade , Procedimentos de Ancoragem Ortodôntica , Humanos , Procedimentos de Ancoragem Ortodôntica/métodos
17.
Cancer Med ; 12(2): 2104-2116, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35789547

RESUMO

BACKGROUND: N6-methyladenosine (m6 A) plays an essential role in tumorigenesis and cancer progression. Long noncoding RNAs (lncRNAs) are discovered to be important targets of m6 A modification, and they play fundamental roles in diverse biological processes. However, there is still a lack of knowledge with regards to the association between m6 A and lncRNAs in human tumors. METHODS: The relationship between lncRNAs and 21 m6 A regulators was comprehensively explored, through the integration of multi-omics data from M6A2Target, m6A-Atlas, and TCGA (The Cancer Genome Atlas). In order to explore the potential roles of m6A-related lncRNAs in human tumors, three applicable methods were introduced, which include the construction of ceRNA networks, drug sensitivity estimation, and survival analysis. RESULTS: A substantial number of positive correlation events across 33 cancer types were found. Moreover, cancer-specific lncRNAs were associated with tissue specificity, and cancer-common lncRNAs were conserved in cancer-related biological function. In particular, the m6 A-related lncRNA FGD5-AS1 was found to be associated with cancer treatment, through its influence on cisplatin resistance in breast cancer patients. Finally, a user-friendly interface Lnc2m6A, which is enriched with various browsing sections resource for the exhibition of relationships and putative biogenesis between lncRNAs and m6 A modifications, is offered in http://hainmu-biobigdata.com/Lnc2m6A. CONCLUSIONS: In summary, the results from this paper will provide a valuable resource that guides both mechanistic and therapeutic roles of m6 A-related lncRNAs in human tumors.


Assuntos
Neoplasias da Mama , RNA Longo não Codificante , Humanos , Feminino , RNA Longo não Codificante/genética , Carcinogênese , Transformação Celular Neoplásica , Adenosina
18.
Theranostics ; 13(5): 1490-1505, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37056564

RESUMO

Background: Glioblastomas are the most common and malignant central nervous system (CNS) tumors that occupied a highly heterogeneous tumor microenvironment (TIME). Long noncoding RNAs (lncRNAs), whose expression can be modified by DNA methylation, are emerging as critical regulators in the immune system. However, knowledge about the epigenetic changes in lncRNAs and their contribution to the immune heterogeneity of glioma is still lacking. Methods: In this study, we integrated paired methylome and transcriptome datasets of glioblastomas and identified 2 robust immune subtypes based on lncRNA methylation features. The immune characteristics of glioma subtypes were compared. Furthermore, immune-related lncRNAs were identified and their relationships with immune evasion were evaluated. Results: Glioma immunophenotypes exhibited distinct immune-related characteristics as well as clinical and epigenetic features. 149 epigenetically regulated (ER) lncRNAs were recognized that possessed inverse variation in epigenetic and transcriptional levels between glioma subtypes. Immune-related lncRNAs were further identified through the investigation of their correlation with immune cell infiltrations and immune-related pathways. In particular, the 'Hot' glioma subtype with higher immunoactivity while a worse survival outcome was found to character immune evasion features. We finally prioritized candidate ER lncRNAs associated with immune evasion markers and response to glioma immunotherapy. Among them, CD109-AS1 and LINC02447 were validated as novel immunoevasive biomarkers for glioma through in vitro experiments. Conclusion: In summary, our study systematically reveals the crosstalk among DNA methylation, lncRNA, and immune regulation in glioblastomas, and will facilitate the development of epigenetic immunotherapy approaches.


Assuntos
Glioblastoma , RNA Longo não Codificante , Evasão Tumoral , Glioblastoma/genética , Glioblastoma/imunologia , Glioblastoma/patologia , Metilação de DNA , Humanos , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Metilação , Imunofenotipagem , Microambiente Tumoral , Glioma/genética , Glioma/imunologia , Glioma/patologia , Epigênese Genética
19.
Cancer Med ; 12(16): 17428-17444, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37401400

RESUMO

BACKGROUND: Forkhead box (FOX) proteins belong to one of the largest transcription factor families and play crucial roles in the initiation and progression of cancer. Prior research has linked several FOX genes, such as FOXA1 and FOXM1, to the crucial process of carcinogenesis. However, the overall picture of FOX gene family across human cancers is far from clear. METHODS: To investigate the broad molecular signatures of the FOX gene family, we conducted study on multi-omics data (including genomics, epigenomics and transcriptomics) from over 11,000 patients with 33 different types of human cancers. RESULTS: Pan-cancer analysis reveals that FOX gene mutations were found in 17.4% of tumor patients with a substantial cancer type-dependent pattern. Additionally, high expression heterogeneity of FOX genes across cancer types was discovered, which can be partially attributed to the genomic or epigenomic alteration. Co-expression network analysis reveals that FOX genes may exert functions by regulating the expression of both their own and target genes. For a clinical standpoint, we provided 103 FOX gene-drug target-drug predictions and found FOX gene expression have potential survival predictive value. All of the results have been included in the FOX2Cancer database, which is freely accessible at http://hainmu-biobigdata.com/FOX2Cancer. CONCLUSION: Our findings may provide a better understanding of roles FOX genes played in the development of tumors, and help to offer new avenues for uncovering tumorigenesis and unprecedented therapeutic targets.


Assuntos
Multiômica , Neoplasias , Humanos , Neoplasias/patologia , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica , Transformação Celular Neoplásica
20.
Chemistry ; 18(44): 13968-73, 2012 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-23015459

RESUMO

[FeFe] hydrogenase mimics: two polynuclear iron-sulfur complexes (1 and 2) were prepared and structurally characterized. They are potentially effective and stable multielectron-transfer relays for mediating four- and six-electron transformations via a cascade of reversible two-electron redox steps with relatively narrow potential spans.


Assuntos
Complexos de Coordenação/química , Ferro/química , Enxofre/química , Cristalografia por Raios X , Técnicas Eletroquímicas , Transporte de Elétrons , Elétrons , Hidrogenase/química , Hidrogenase/metabolismo , Proteínas Ferro-Enxofre/química , Proteínas Ferro-Enxofre/metabolismo , Conformação Molecular , Oxirredução
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