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1.
Cell Stem Cell ; 30(8): 1110-1123.e9, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37541214

RESUMO

Mechanical forces are known to be important in mammalian blastocyst formation; however, due to limited tools, specific force inputs and how they relay to first cell fate control of inner cell mass (ICM) and/or trophectoderm (TE) remain elusive. Combining in toto live imaging and various perturbation experiments, we demonstrate and measure fluid flow forces existing in the mouse blastocyst cavity and identify Klf2(Krüppel-like factor 2) as a fluid force reporter with force-responsive enhancers. Long-term live imaging and lineage reconstructions reveal that blastomeres subject to higher fluid flow forces adopt ICM cell fates. These are reinforced by internal ferrofluid-induced flow force assays. We also utilize ex vivo fluid flow force mimicking and pharmacological perturbations to confirm mechanosensing specificity. Together, we report a genetically encoded reporter for continuously monitoring fluid flow forces and cell fate decisions and provide a live imaging framework to infer force information enriched lineage landscape during development. VIDEO ABSTRACT.


Assuntos
Blastocisto , Fatores de Transcrição , Camundongos , Animais , Diferenciação Celular , Fatores de Transcrição/genética , Desenvolvimento Embrionário , Linhagem da Célula , Mamíferos
2.
IEEE Trans Cybern ; 52(9): 8793-8803, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33710967

RESUMO

Time-series forecasting is a key component in the automation and optimization of intelligent applications. It is not a trivial task, as there are various short-term and/or long-term temporal dependencies. Multiscale modeling has been considered as a promising strategy to solve this problem. However, the existing multiscale models either apply an implicit way to model the temporal dependencies or ignore the interrelationships between multiscale subseries. In this article, we propose a multiscale interactive recurrent network (MiRNN) to jointly capture multiscale patterns. MiRNN employs a deep wavelet decomposition network to decompose the raw time series into multiscale subseries. MiRNN introduces three key strategies (truncation, initialization, and message passing) to model the inherent interrelationships between multiscale subseries, as well as a dual-stage attention mechanism to capture multiscale temporal dependencies. Experiments on four real-world datasets demonstrate that our model achieves promising performance compared with the state-of-the-art methods.


Assuntos
Fatores de Tempo , Previsões
3.
Fundam Res ; 2(1): 14-22, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38933910

RESUMO

To form fully functional four-chambered structure, mammalian heart development undergoes a transient finger-shaped trabeculae, crucial for efficient contraction and exchange for gas and nutrient. Although its developmental origin and direct relevance to congenital heart disease has been studied extensively, the time-resolved cellular mechanism underlying hypotrabeculation remains elusive. Here, we employed in toto live imaging and reconstructed the holistic cell lineages and cellular behavior landscape of control and hypotrabeculed hearts of mouse embryos from E9.5 for up to 24 h. Compared to control, hypotrabeculation in ErbB2 mutants arose mainly through dual mechanisms: both reduced proliferation of trabecular cardiomyocytes from early cell fate segregation and markedly impaired oriented cell division and migration. Further examination of mosaic mutant hearts confirmed alterations in cellular behaviors in a cell autonomous manner. Thus, our work offers a framework for continuous live imaging and digital cell lineage analysis to better understand subtle pathological alterations in congenital heart disease.

4.
Materials (Basel) ; 14(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34640122

RESUMO

It is difficult to accurately predict the surface roughness of belt grinding with superalloy materials due to the uneven material distribution and complex material processing. In this paper, a radial basis neural network is proposed to predict surface roughness. Firstly, the grinding system of the superalloy belt is introduced. The effects of the material removal process and grinding parameters on the surface roughness in belt grinding were analyzed. Secondly, an RBF neural network is trained by reinforcement learning of a self-organizing mapping method. Finally, the prediction accuracy and simulation results of the proposed method and the traditional prediction method are analyzed using the ten-fold cross method. The results show that the relative error of the improved RLSOM-RBF neural network prediction model is 1.72%, and the R-value of the RLSOM-RBF fitting result is 0.996.

5.
Dent Mater J ; 39(5): 855-861, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32461510

RESUMO

This study was evaluating how three desensitizing toothpastes used at home influence the effect associated with desensitizing agents after application in the clinic. Fifty dentine disks measure it permeability and 32 dentine disks with similar permeability levels were selected. Following Dental desensitizer treatment, dentine disks were randomly divided into three subgroups (n=10) that received applications of three toothpastes, respectively. The permeability (Lp) of each specimen was measured after each treatment. One specimen was selected from each group for scanning electron microscopy (SEM) observation. After each treatment, the Lp values decreased significantly for each group (p<0.05) and either completely or partially blocked the dentine tubules upon SEM observation. However, no significant differences in Lp values were observed amongst subgroups (p>0.05). After using the Dental desensitizer, Sensodyne, Crest and Colgate desensitizing toothpastes both can continued to reduce the permeability of the dentine disk, and no significant differences were found amongst them.


Assuntos
Dessensibilizantes Dentinários/farmacologia , Sensibilidade da Dentina/tratamento farmacológico , Sensibilidade da Dentina/prevenção & controle , Dentina , Permeabilidade da Dentina/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Fluoreto de Sódio/farmacologia , Cremes Dentais/farmacologia
6.
Nat Cell Biol ; 22(3): 332-340, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32123336

RESUMO

Mapping of the holistic cell behaviours sculpting the four-chambered mammalian heart has been a goal or previous studies, but so far only success in transparent invertebrates and lower vertebrates with two-chambered hearts has been achieved. Using a live-imaging system comprising a customized vertical light-sheet microscope equipped with a mouse embryo culture module, a heartbeat-gated imaging strategy and a digital image processing framework, we realized volumetric imaging of developing mouse hearts at single-cell resolution and with uninterrupted cell lineages for up to 1.5 d. Four-dimensional landscapes of Nppa+ cardiomyocyte cell behaviours revealed a blueprint for ventricle chamber formation by which biased outward migration of the outermost cardiomyocytes is coupled with cell intercalation and horizontal division. The inner-muscle architecture of trabeculae was developed through dual mechanisms: early fate segregation and transmural cell arrangement involving both oriented cell division and directional migration. Thus, live-imaging reconstruction of uninterrupted cell lineages affords a transformative means for deciphering mammalian organogenesis.


Assuntos
Ventrículos do Coração/citologia , Ventrículos do Coração/embriologia , Processamento de Imagem Assistida por Computador/métodos , Miócitos Cardíacos/citologia , Animais , Divisão Celular , Linhagem da Célula , Movimento Celular , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário , Coração/embriologia , Camundongos , Microscopia , Morfogênese , Miocárdio/citologia , Análise de Célula Única , Técnicas de Cultura de Tecidos
7.
J Prosthet Dent ; 124(1): 26-35.e2, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31753461

RESUMO

STATEMENT OF PROBLEM: Differences between ceramic and metal-ceramic implant-supported fixed dental prostheses are unclear. PURPOSE: The purpose of this systematic review and meta-analysis was to compare the technical, biological, and esthetic complication rates of implant-supported ceramic and metal-ceramic restorations. MATERIAL AND METHODS: Six databases were searched to identify randomized controlled clinical trials (RCTs) and prospective and retrospective cohort studies of implant-supported fixed dental prostheses. The survival rate, marginal adaptation, marginal bone loss, pocket probing depth, crown color match, and mucosal discoloration of ceramic and metal-ceramic single crowns were assessed. For implant-supported fixed partial dental prostheses (FPDPs), only the survival rate was assessed. The risk of bias was assessed for individual studies and across studies by using the Cochrane guidelines, Newcastle-Ottawa scale, and funnel plots. RESULTS: Twenty studies were included in this meta-analysis. Ceramic and metal-ceramic implant-supported single crowns were compared in terms of the survival rate (OR=0.84 [0.32, 2.23], P=.730), marginal adaptation (mean difference [MD]=0.33 [0.19, 0.47], P<.001), marginal bone loss (MD=-0.03 [-0.07, 0.02], P=.260), pocket probing depth (MD=-0.07 [-0.14, 0.00], P=.060), crown color match (MD=-0.15 [-0.29, 0.00], P=.040), and mucosal discoloration (standardized mean difference [SMD]=-0.14 [-0.86, 0.58], P=.710). The survival rate of ceramic and metal-ceramic implant-supported FPDPs was also compared (odds ratio [OR]=1.92 [1.26, 2.94], P=.003). CONCLUSIONS: No significant difference was observed between ceramic and metal-ceramic implant-supported single crowns in terms of the survival rate, marginal bone loss, pocket probing depth, or mucosal discoloration. However, metal-ceramic single crowns had better marginal adaptation and poorer crown color match than did ceramic single crowns. In addition, current evidence indicates that metal-ceramic implant-supported FPDPs might have a higher survival rate than ceramic FPDPs.


Assuntos
Implantes Dentários , Falha de Restauração Dentária , Cerâmica , Coroas , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Estética Dentária , Metais
8.
Clin Oral Investig ; 24(6): 1917-1928, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31478097

RESUMO

OBJECTIVES: This network meta-analysis compares different lasers, placebo, and no treatment in terms of their effects on dentine hypersensitivity (DH) immediately after treatment and over the long term (1 month). METHODS: A systematic electronic literature search of four databases and a manual search were performed to identify randomized controlled trials (RCTs) examining different laser treatments for the treatment of DH. Pairwise and network meta-analyses were performed to analyze the desensitization effect immediately after treatment and over the long term. The risk of bias was assessed based on the Cochrane guidelines and funnel plots. The quality of the evidence, statistical heterogeneity, inconsistencies, and ranking probability were also evaluated. RESULTS: A total of 11 RCTs were included in the network meta-analysis; 11 and 9 of these studies analyzed immediate and long-term effects, respectively. All four types of laser had a better desensitizing effect than controls immediately after treatment and over the long term, but there were no significant differences among the four different lasers. There was a significant placebo effect immediately after treatment. The laser with the highest probability of being the most effective treatment for DH was Er,Cr:YSGG immediately after treatment and over the long term (73% and 47%, respectively). CONCLUSIONS: All four types of laser had significantly better effects than no treatment on DH immediately after treatment and in the long term, but there were no significant differences among the four lasers. In addition, there was a significant placebo effect, supporting the importance of including a placebo group in future studies. Furthermore, Er,Cr:YSGG may be the most effective laser for the treatment of DH immediately and over the long term. CLINICAL RELEVANCE: This study used network meta-analyses to compare different lasers, placebo, and no treatment over different time periods, which is to provide guidance for selecting an appropriate laser treatment in patients with DH.


Assuntos
Sensibilidade da Dentina , Terapia a Laser , Terapia com Luz de Baixa Intensidade , Sensibilidade da Dentina/terapia , Humanos , Lasers , Metanálise em Rede , Resultado do Tratamento
9.
J Evid Based Dent Pract ; 19(2): 115-130, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31326044

RESUMO

OBJECTIVES: The aim of the study was to evaluate the immediate and long-term desensitizing effect of lasers in reducing dentine hypersensitivity (DH) compared with negative controls. MATERIAL AND METHODS: Six databases were searched to identify relevant articles published up to June 8, 2018. Randomized controlled trials comparing lasers with placebo or no treatment control in adult patients who suffer from DH were included. The risk of bias was assessed according to the Cochrane guidelines, and the quality of the evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation tool. Inverse-variance random effects meta-analyses of standardized mean differences and 95% confidence intervals were performed using the RevMan 5.3 software. RESULTS: Twenty-two randomized controlled trials were finally included in the meta-analysis, and 21 studies of these were conducted to analyze the immediate and long-term effects. All types of lasers had better immediate and long-term desensitizing effects on DH than negative controls. The quality of evidence of the included studies showed that lasers compared with negative controls had moderate-quality immediate and long-term effects on DH. The statistical heterogeneity of these comparisons was high, for which the result of I2 ranged from 90% to 98%. CONCLUSIONS: Our results indicate that all types of lasers had a better desensitizing effect on DH than negative controls, both in immediate and long term. Furthermore, more high-quality studies with a large sample size are needed to confirm our results (PROSPERO CRD42018102260).


Assuntos
Sensibilidade da Dentina , Terapia a Laser , Adulto , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
J Dent ; 88: 103170, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31325467

RESUMO

OBJECTIVES: This network meta-analysis compares different desensitizing toothpastes and placebo in terms of their effects on dentine hypersensitivity (DH) at 2, 4, and 8 weeks. MATERIALS AND METHODS: A systematic electronic literature search of four databases, and a manual search, were performed to identify randomized controlled trials (RCTs) on different desensitizing toothpastes for the treatment of DH. Pair-wise and network meta-analyses were performed to analyze the desensitization effect at 2, 4, and 8 weeks. The risk of bias was assessed based on the Cochrane guidelines and funnel plots. Statistical heterogeneity, inconsistencies, and ranking probability were also evaluated. RESULTS: A total of 30 RCTs were included in the network meta-analysis, which included eight desensitizing toothpastes. There was no significant difference in the effect among calcium sodium phosphosilicate-containing (CSPS), potassium-containing (K) and strontium-containing (Sr) toothpastes. In addition, there was no significant difference between fluoride (F) and placebo. The desensitizing toothpaste with the highest probability of being the most effective treatment for DH was nano-hydroxyapatite (n-HA) at 2 and 4 weeks (60% and 67%, respectively), and Ar at 8 weeks (54%). CONCLUSIONS: No significant difference was detected in desensitizing effects among CSPS, K and Sr toothpastes. In addition, there was no significant difference between F and placebo, K and placebo. Furthermore, a significant placebo effect on DH was found in this study. Moreover, n-HA toothpastes may be the best desensitizing toothpastes for treatment of DH, followed by Ar toothpaste. CLINICAL SIGNIFICANCE: Based on the results of present network meta-analysis, n-HA containing toothpastes might be a recommended desensitizing toothpastes considering the treatment of DH. PROSPERO registration number: CRD42019117710.


Assuntos
Dessensibilizantes Dentinários/uso terapêutico , Sensibilidade da Dentina/tratamento farmacológico , Cremes Dentais/farmacologia , Fluoretos , Humanos , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Cremes Dentais/química , Cremes Dentais/uso terapêutico
11.
J Dent ; 75: 12-21, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29787782

RESUMO

OBJECTIVES: To evaluate the desensitizing effect of toothpastes that contain ingredients that act against dentine hypersensitivity (DH) and to compare this effect with negative controls. SOURCES: Five databases were searched to identify relevant articles published up to November 27, 2017. STUDY SELECTION: Randomized controlled trials (RCTs) comparing desensitizing toothpastes with a toothpastes without desensitizing component in adult patients that suffer from DH were included. The risk of bias was assessed according to the Cochrane guidelines, and the quality of the evidence was evaluated using the GRADE tool. Inverse variance random-effects meta-analyses of standardized mean differences (SMD) and 95% confidence intervals (CIs) were calculated using RevMan 5.3 software. DATA: 53 RCTs with 4796 patients were finally included in the meta-analysis. The toothpastes that contain active desensitization ingredients showed a better desensitizing effect on DH than the negative control, except the strontium- and amorphous calcium phosphate-containing toothpastes. The amorphous calcium phosphate-containing toothpaste had very low-quality evidence, the strontium, potassium and strontium, and potassium and stannous fluoride-containing toothpastes had low-quality evidence, and the other five toothpastes had moderate quality evidence. CONCLUSIONS: Our result support the premise that toothpastes containing potassium, stannous fluoride, potassium and strontium, potassium and stannous fluoride, calcium sodium phosphosilicate, arginine, and nano-hydroxyapatite relieve the symptoms of DH, but does not advise the use of toothpastes that contain strontium and amorphous calcium phosphate. Furthermore, high-quality studies are needed to confirm our results. (PROSPERO CRD42018085639).


Assuntos
Dessensibilizantes Dentinários , Sensibilidade da Dentina , Adulto , Fluoretos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estrôncio , Fluoretos de Estanho , Cremes Dentais
12.
ACS Appl Mater Interfaces ; 7(8): 4921-7, 2015 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-25664376

RESUMO

A self-powered active strain sensor based on well-aligned (K,Na)NbO3 piezoelectric nanofibers is successfully fabricated through the electrospinning and polymer packaging process. The device exhibits a fast, active response to dynamic strain by generating impulsive voltage signal that is dependent on the amplitude of the dynamic strains and the vibration frequency. When the frequency is fixed at 1 Hz, the peak to peak value of the voltage increases from ∼1 to ∼40 mV, and the strain changes from 1 to 6%. Furthermore, the output voltage is linearly increased by an order of magnitude with the frequency changing from 0.2 to 5 Hz under the same strain amplitude. The influence of frequency on the output voltage can be further enhanced at higher strain amplitude. This phenomenon is attributed to the increased generating rate of piezoelectric charges under higher strain rate of the nanofibers. By counting the pulse separation of the voltage peaks, the vibration frequency is synchronously measured during the sensing process. The accuracy of the sensing results can be improved by calibration according to the frequency-dependent sensing behavior.

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