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1.
Development ; 148(8)2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33766930

RESUMO

Stem cells self-renew or give rise to transit-amplifying cells (TACs) that differentiate into specific functional cell types. The fate determination of stem cells to TACs and their transition to fully differentiated progeny is precisely regulated to maintain tissue homeostasis. Arid1a, a core component of the switch/sucrose nonfermentable complex, performs epigenetic regulation of stage- and tissue-specific genes that is indispensable for stem cell homeostasis and differentiation. However, the functional mechanism of Arid1a in the fate commitment of mesenchymal stem cells (MSCs) and their progeny is not clear. Using the continuously growing adult mouse incisor model, we show that Arid1a maintains tissue homeostasis through limiting proliferation, promoting cell cycle exit and differentiation of TACs by inhibiting the Aurka-Cdk1 axis. Loss of Arid1a overactivates the Aurka-Cdk1 axis, leading to expansion of the mitotic TAC population but compromising their differentiation ability. Furthermore, the defective homeostasis after loss of Arid1a ultimately leads to reduction of the MSC population. These findings reveal the functional significance of Arid1a in regulating the fate of TACs and their interaction with MSCs to maintain tissue homeostasis.


Assuntos
Aurora Quinase A/metabolismo , Proteína Quinase CDC2/metabolismo , Proteínas de Ligação a DNA/metabolismo , Incisivo/embriologia , Células-Tronco Mesenquimais/metabolismo , Mitose , Transdução de Sinais , Fatores de Transcrição/metabolismo , Animais , Aurora Quinase A/genética , Proteína Quinase CDC2/genética , Proteínas de Ligação a DNA/genética , Camundongos , Camundongos Transgênicos , Fatores de Transcrição/genética
2.
Small ; : e2310964, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030863

RESUMO

Photodynamic therapy (PDT) is long-standing suffered from elevated tumor interstitial fluid pressure (TIFP) and prevalent hypoxic microenvironment within the solid malignancies. Herein, sound-activated flexocatalysis is developed to overcome the dilemma of PDT through both enhancing tumor penetration of photosensitizers by reducing TIFP and establishing an oxygen-rich microenvironment. In detail, a Schottky junction is constructed by flexocatalyst MoSe2 nanoflowers and Pt. Subsequently, the Schottky junction is loaded with the photosensitizer indocyanine green (ICG) and encapsulated within tumor cytomembrane to constitute a bionic-flexocatalytic nanomedicine (MPI@M). After targeting the tumor, MPI@M orchestrates flexocatalytic water splitting in tumor interstitial fluid under acoustic stimulation to lower TIFP, which boosted the tumor penetration of ICG. Concurrently, the oxygen released from the flexocatalytic water splitting overcomes the limitation of hypoxia against PDT. Furthermore, superfluous singlet oxygen generated by PDT can induce mitochondrial dysfunction for further tumor cell apoptosis. After 60 min of flexocatalysis, both the 30% decrease of TIFP and the relieved tumor hypoxia are observed, significantly promoting the therapeutic effect of PDT. Consequently, MoSe2/Pt junction nanoflowers, with the excellent flexocatalytic performance, hold significant potential for future applications in biocatalytic cancer therapies.

3.
BMC Oral Health ; 24(1): 182, 2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38311732

RESUMO

BACKGROUND: Periodontitis is closely associated with chronic systemic diseases. Healthy lifestyle interventions have health-enhancing effects on chronic systemic disorders and periodontitis, but the extent to which healthy lifestyle combinations are associated with periodontitis is unclear. Therefore, this study aimed to investigate the association between periodontitis and different healthy lifestyle combinations. METHODS: 5611 participants were included from the National Health and Nutrition Examination Survey (NHANES, 2009-2014). Six healthy lifestyles factors were defined as fulfilling either: non-smoking, moderate drinking, moderate body mass index (BMI), physical activity, healthy sleep and appropriate total energy intake. Then, the adjusted logistic regression models were performed to identify the association between the periodontitis and the scoring system composed of six lifestyles (0-6 scale). Finally, different scenarios were dynamically and randomly combined to identify the optimal and personalized combination mode. RESULTS: Higher healthy lifestyle scores were significantly associated with lower periodontitis prevalence (p < 0.05). Four lifestyle factors (smoking, drinking, BMI, and sleep) significantly varied between the periodontitis and healthy groups (p < 0.05). Smoking was considered as a strong independent risk factor for periodontitis in both former and current smokers. Results further indicated that the combination of these four lifestyles played the most essential role in determining the magnitude of periodontitis occurrence (odds ratio [OR]: 0.33; 95% confidence interval [CI]: 0.21 to 0.50). In the total population, the majority of three lifestyle combinations outperformed the two combination models, whereas the two-combination of nonsmoking-drinking (OR: 0.39; 95% CI: 0.27 to 0.58) had relatively lower periodontitis prevalence than the three-combination of healthy drinking-BMI-sleep (OR: 0.42; 95% CI: 0.26 to 0.66). CONCLUSION: This cross-sectional study suggests that smoking, drinking, BMI, and sleep are significantly related with periodontitis and smoking is the principal risk factor related among them. This study provides various customized lifestyle combinations for periodontitis prevention.


Assuntos
Periodontite , Humanos , Inquéritos Nutricionais , Estudos Transversais , Periodontite/epidemiologia , Fatores de Risco , Estilo de Vida Saudável , Doença Crônica
4.
J Nanobiotechnology ; 21(1): 346, 2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37741978

RESUMO

As societal aging intensifies, senile osteoporosis has become a global public health concern. Bone microdamage is mainly caused by processes such as enhancing osteoclast activity or reducing bone formation by osteoblast-lineage cells. Compared with young individuals, extracellular vesicles derived from senescent bone marrow mesenchymal stem cells(BMSCs) increase the transient differentiation of bone marrow monocytes (BMMs) to osteoclasts, ultimately leading to osteoporosis and metal implant failure. To address this daunting problem, an exosome-targeted orthopedic implant composed of a nutrient coating was developed. A high-zinc atmosphere used as a local microenvironmental cue not only could inhibit the bone resorption by inhibiting osteoclasts but also could induce the reprogramming of senile osteogenesis and osteoclast dialogue by exosome modification. Bidirectional regulation of intercellular communication via cargoes, including microRNAs carried by exosomes, was detected. Loss- and gain-of-function experiments demonstrated that the key regulator miR-146b-5p regulates the protein kinase B/mammalian target of rapamycin pathway by targeting the catalytic subunit gene of PI3K-PIK3CB. In vivo evaluation using a naturally-aged osteoporotic rat femoral defect model further confirmed that a nutrient coating substantially augments cancellous bone remodeling and osseointegration by regulating local BMMs differentiation. Altogether, this study not only reveals the close link between senescent stem cell communication and age-related osteoporosis but also provides a novel orthopedic implant for elderly patients with exosome modulation capability.


Assuntos
Exossomos , Osteoclastos , Idoso , Humanos , Animais , Ratos , Osteogênese , Zinco , Envelhecimento , Mamíferos
5.
J Prosthet Dent ; 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37648618

RESUMO

A novel technique of digitally printed custom trays assembled with occlusion rims and gothic arch tracing devices attached with tenon-and-mortise joints for biofunctional complete dentures that could be delivered in 2 visits is presented. This technique takes advantage of closed-mouth impressions and objective jaw relation records by following the biofunctional prosthetic system concept with high efficiency and reduced labor.

6.
Int J Mol Sci ; 22(13)2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34281250

RESUMO

Amelogenin comprises ~90% of enamel proteins; however, the involvement of Amelx transcriptional activation in regulating ameloblast differentiation from induced pluripotent stem cells (iPSCs) remains unknown. In this study, we generated doxycycline-inducible Amelx-expressing mouse iPSCs (Amelx-iPSCs). We then established a three-stage ameloblast induction strategy from Amelx-iPSCs, including induction of surface ectoderm (stage 1), dental epithelial cells (DECs; stage 2), and ameloblast lineage (stage 3) in sequence, by manipulating several signaling molecules. We found that adjunctive use of lithium chloride (LiCl) in addition to bone morphogenetic protein 4 and retinoic acid promoted concentration-dependent differentiation of DECs. The resulting cells had a cobblestone appearance and keratin14 positivity. Attenuation of LiCl at stage 3 together with transforming growth factor ß1 and epidermal growth factor resulted in an ameloblast lineage with elongated cell morphology, positivity for ameloblast markers, and calcium deposition. Although stage-specific activation of Amelx did not produce noticeable phenotypic changes in ameloblast differentiation, Amelx activation at stage 3 significantly enhanced cell adhesion as well as decreased proliferation and migration. These results suggest that the combination of inducible Amelx transcription and stage-specific ameloblast induction for iPSCs represents a powerful tool to highlight underlying mechanisms in ameloblast differentiation and function in association with Amelx expression.


Assuntos
Ameloblastos/citologia , Ameloblastos/metabolismo , Amelogenina/metabolismo , Ameloblastos/fisiologia , Amelogenina/genética , Animais , Adesão Celular/fisiologia , Diferenciação Celular/fisiologia , Doxiciclina/farmacologia , Células Epiteliais/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , Transdução de Sinais , Ativação Transcricional/fisiologia
7.
Nat Mater ; 18(6): 627-637, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31114073

RESUMO

Cells are transplanted to regenerate an organs' parenchyma, but how transplanted parenchymal cells induce stromal regeneration is elusive. Despite the common use of a decellularized matrix, little is known as to the pivotal signals that must be restored for tissue or organ regeneration. We report that Alx3, a developmentally important gene, orchestrated adult parenchymal and stromal regeneration by directly transactivating Wnt3a and vascular endothelial growth factor. In contrast to the modest parenchyma formed by native adult progenitors, Alx3-restored cells in decellularized scaffolds not only produced vascularized stroma that involved vascular endothelial growth factor signalling, but also parenchymal dentin via the Wnt/ß-catenin pathway. In an orthotopic large-animal model following parenchyma and stroma ablation, Wnt3a-recruited endogenous cells regenerated neurovascular stroma and differentiated into parenchymal odontoblast-like cells that extended the processes into newly formed dentin with a structure-mechanical equivalency to native dentin. Thus, the Alx3-Wnt3a axis enables postnatal progenitors with a modest innate regenerative capacity to regenerate adult tissues. Depleted signals in the decellularized matrix may be reinstated by a developmentally pivotal gene or corresponding protein.


Assuntos
Proteínas de Homeodomínio/metabolismo , Tecido Parenquimatoso/fisiologia , Dente/citologia , Dente/embriologia , Adolescente , Animais , Feminino , Proteínas de Homeodomínio/genética , Humanos , Incisivo/citologia , Incisivo/embriologia , Camundongos Endogâmicos , Dente Serotino/citologia , Técnicas de Cultura de Órgãos , Tecido Parenquimatoso/citologia , Gravidez , Regiões Promotoras Genéticas , Regeneração , Células Estromais/fisiologia , Suínos , Fator A de Crescimento do Endotélio Vascular/genética , Proteína Wnt3A/genética , Proteína Wnt3A/metabolismo
8.
J Pathol ; 248(4): 438-451, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30900255

RESUMO

The mineralocorticoid receptor (MR) plays important roles in cardiovascular pathogenesis. The function of MR in angiogenesis is still controversial. This study aimed to explore the role of endothelial MR in angiogenesis and to delineate the underlying mechanism. Endothelial-hematopoietic MR knockout (EMRKO) mice were generated and subjected to hindlimb ischemia and injection of melanoma cells. Laser Doppler measurements showed that EMRKO mice had improved blood flow recovery and increased vessel density in ischemic limbs. In addition, EMRKO accelerated growth and increased the vessel density of tumors. Matrigel implantation, aortic ring assays, and tube formation assays demonstrated that MRKO endothelial cells (ECs) manifested increased angiogenic potential. MRKO ECs also displayed increased migration ability and proliferation. MRKO and MR knockdown both upregulated gene expression, protein level, and phosphorylation of signal transducer and activator of transcription 3 (STAT3). Stattic, a selective STAT3 inhibitor, attenuated the effects of MRKO on tube formation, migration, and proliferation of ECs. At the molecular level, MR interacted with CCAAT enhancer-binding protein beta (C/EBPß) to suppress the transcription of STAT3. Furthermore, interactions between MR and STAT3 blocked the phosphorylation of STAT3. Finally, stattic abolished the pro-angiogenic phenotype of EMRKO mice. Taken together, endothelial MR is a negative regulator of angiogenesis, likely in a ligand-independent manner. Mechanistically, MR downregulates STAT3 that mediates the impacts of MR deficiency on the angiogenic activity of ECs and angiogenesis. Targeting endothelial MR may be a potential pro-angiogenic strategy for ischemic diseases. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Células Endoteliais/metabolismo , Neovascularização Patológica/metabolismo , Receptores de Mineralocorticoides/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Biomarcadores/metabolismo , Movimento Celular , Proliferação de Células , Regulação para Baixo , Células Endoteliais/patologia , Feminino , Masculino , Camundongos , Camundongos Knockout , Neovascularização Patológica/patologia , Neovascularização Patológica/fisiopatologia
9.
J Biol Chem ; 293(3): 1030-1039, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29203528

RESUMO

Type I IFN production and signaling in macrophages play critical roles in innate immune responses. High salt (i.e. high concentrations of NaCl) has been proposed to be an important environmental factor that influences immune responses in multiple ways. However, it remains unknown whether high salt regulates type I IFN production and signaling in macrophages. Here, we demonstrated that high salt promoted IFNß production and its signaling in both human and mouse macrophages, and consequentially primed macrophages for strengthened immune sensing and signaling when challenged with viruses or viral nucleic acid analogues. Using both pharmacological inhibitors and RNA interference we showed that these effects of high salt on IFNß signaling were mediated by the p38 MAPK/ATF2/AP1 signaling pathway. Consistently, high salt increased resistance to vesicle stomatitis virus (VSV) infection in vitro. In vivo data indicated that a high-salt diet protected mice from lethal VSV infection. Taken together, these results identify high salt as a crucial regulator of type I IFN production and signaling, shedding important new light on the regulation of innate immune responses.


Assuntos
Interferon Tipo I/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Cloreto de Sódio/farmacologia , Animais , Antivirais/farmacologia , Western Blotting , Farmacorresistência Viral , Humanos , Imunidade Inata , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
J Cell Physiol ; 234(4): 4005-4014, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30256390

RESUMO

Cementum, which shares common features with bone in terms of biochemical composition, is important for the homeostasis of periodontium during periodontitis and orthodontic treatment. Sirtuin 6 (SIRT6), as a member of the sirtuin family, plays key roles in the osteogenic differentiation of bone marrow mesenchymal stem cells. However, the involvement of SIRT6 in cementoblast differentiation and mineralization and the underlying mechanisms remain unknown. In this study, we observed that the expression of SIRT6 increased during cementoblast differentiation initially. Analysis of the gain- and loss-of-function indicated that overexpressing SIRT6 in OCCM-30 cells suppresses cementoblast differentiation and mineralization and downregulating SIRT6 promotes cementogenesis. GLUT1, a glucose transporter necessary in cementogenesis, was inhibited by SIRT6. Overexpressing GLUT1 in SIRT6-overexpressed OCCM-30 cells rescued the inhibitory effect of SIRT6 on cementoblast differentiation and mineralization. Moreover, AMPK was activated after overexpressing SIRT6 and inhibited cementoblast differentiation and mineralization. Downregulating the expression of SIRT6 inhibited AMPK activity. Meanwhile, GLUT1 overexpression significantly decreased AMPK activity. Overall, on one hand, SIRT6 inhibited cementoblast differentiation and mineralization by suppressing GLUT1. On the other hand, SIRT6 inhibited cementoblast differentiation and mineralization by activating the AMPK pathway. GLUT1 overexpression also rescued the increased AMPK pathway activated by SIRT6.


Assuntos
Cementogênese , Cemento Dentário/enzimologia , Transportador de Glucose Tipo 1/metabolismo , Sirtuínas/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Cemento Dentário/citologia , Transportador de Glucose Tipo 1/genética , Camundongos , Transdução de Sinais , Sirtuínas/genética , Regulação para Cima
11.
Clin Oral Implants Res ; 30(10): 1049-1058, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31357237

RESUMO

OBJECTIVE: To evaluate the clinical outcomes of an early loading protocol of splinted implants with a fluoride-modified nanostructure surface and a tapered apex design for the therapy of posterior partial edentulism of mandible. MATERIALS AND METHODS: One hundred and seven implants were placed in the mandible of 45 subjects at three centres in China. A minimum of two and a maximum of three implants were placed in an edentulous region using a one-stage protocol. Each subject received a screw-retained, splinted and fixed permanent prosthesis 6-8 weeks after surgery. Marginal bone level (MBL) change, implant survival and soft tissue health were assessed at 6, 12, 24 and 36 months after loading. A total of 92 implants from 40 subjects were recalled and investigated in this clinical trial. RESULTS: After three-year loading, the survival rate of implant was 100%. On a subject level, there was a mean (±SD) marginal bone gain of 0.23 ± 0.48 mm at 36-month recall and the change in MBL was statistically significant (p = .00061) compared with time of loading. On an implant level, the change in MBL was statistically significant (p = .03914, p = .01494, p = .00000) at 12, 24 and 36 months of loading compared with time of loading. CONCLUSION: Three-year data indicate that early loading protocol of splinted implants with a fluoride-modified nanostructure surface and a tapered apex design is feasible and safe for the therapy of partial edentulism in posterior mandible, which may contribute to bone gain when the suitable occlusal load and oral hygiene maintenance are kept.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , China , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Humanos , Mandíbula , Estudos Prospectivos , Resultado do Tratamento
12.
Small ; 13(24)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28464447

RESUMO

The cellular internalization of rod-like nanoparticles (NPs) is investigated in a combined experimental and simulation study. These rod-like nanoparticles with smooth, abacus-like (i.e., beads-on-wires), and helical surface patterns are prepared by the cooperative self-assembly of poly(γ-benzyl-l-glutamate)-block-poly(ethylene glycol) (PBLG-b-PEG) block copolymers and PBLG homopolymers. All three types of NPs can be internalized via endocytosis. Helical NPs exhibit the best endocytic efficacy, followed by smooth NPs and abacus-like NPs. Coarse-grained molecular dynamics simulations are used to examine the endocytic efficiency of these NPs. The NPs with helical and abacus-like surfaces can be endocytosed via novel "standing up" (tip entry) and "gyroscope-like" (precession) pathways, respectively, which are distinct from the pathway of traditional NPs with smooth surfaces. This finding indicates that the cellular internalization capacity and pathways can be regulated by introducing stripe patterns (helical and abacus-like) onto the surface of rod-like NPs. The results of this study may lead to novel applications of biomaterials, such as advanced drug delivery systems.

13.
J Clin Periodontol ; 43(3): 298-304, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26790007

RESUMO

AIM: To evaluate the 12-months clinical and radiological outcomes with the OsseoSpeed(™) TX implant using an early loading protocol in patients with missing teeth in the posterior mandible. MATERIAL AND METHODS: Forty-five subjects, with Kennedy class I or II edentulism in the mandible, were enrolled at three centres in China. Two or three implants were placed in one edentulous region using a one-stage procedure. Patients received a screw-retained splinted fixed permanent restoration in one edentulous region 6-8 weeks after surgery. Follow-up took place at 6 and 12 months after loading. Marginal bone level alteration, implant survival and clinical findings were assessed using descriptive statistics. The data were analysed on a patient level, implying that the mean overall implants by patient was used as the statistical unit. The data from the three centres were pooled in the statistical analyses. RESULTS: A total of 107 implants were inserted in 45 patients. Twelve months after loading, the implant survival rate was 100%, with a mean (± std) marginal bone gain of 0.08 ± 0.411 mm and healthy soft tissue status. CONCLUSIONS: Early loading of splinted OsseoSpeed(™) TX implants was an effective and safe treatment for partial edentulism of the posterior mandible. CLINICAL TRIAL REGISTRATION NUMBER ON CLINICALTRIALS.GOV: NCT01346683.


Assuntos
Implantes Dentários , Mandíbula , Adulto , Idoso , Perda do Osso Alveolar/cirurgia , China , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Feminino , Humanos , Masculino , Mandíbula/cirurgia , Pessoa de Meia-Idade , Estudos Prospectivos
14.
Nanotechnology ; 25(16): 165102, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24670610

RESUMO

For artificial nerve conduits, great improvements have been achieved in mimicking the structures and components of autologous nerves. However, there are still some problems in conduit construction, especially in terms of mechanical properties, biomimetic surface tomography, electrical conductivity and sustained release of neurotrophic factors or cells. In this study, we designed and fabricated a novel electrospun nerve conduit enhanced by multi-walled carbon nanotubes (MWNTs) on the basis of a collagen/poly(ε-caprolactone) (collagen/PCL) fibrous scaffold. Our aim was to provide further knowledge about the mechanical effects and efficacy of MWNTs on nerve conduits as well as the biocompatibility and toxicology of MWNTs when applied in vivo.The results showed that as one component, carboxyl MWNTs could greatly alter the composite scaffold's hydrophilicity, mechanical properties and degradability. The electrospun fibers enhanced by MWNTs could support Schwann cell adhesion and elongation as a substrate in vitro. In vivo animal studies demonstrated that the MWNT-enhanced collagen/PCL conduit could effectively promote nerve regeneration of sciatic nerve defect in rats and prevent muscle atrophy without invoking body rejection or serious chronic inflammation. All of these results showed that this MWNT-enhanced scaffold possesses good biocompatibility and MWNTs might be excellent candidates as engineered nanocarriers for further neurotrophic factor delivery research.


Assuntos
Regeneração Tecidual Guiada/métodos , Atrofia Muscular/prevenção & controle , Nanotubos de Carbono , Regeneração Nervosa , Nervo Isquiático/fisiologia , Animais , Masculino , Poliésteres , Ratos , Ratos Endogâmicos F344 , Neuropatia Ciática/patologia , Neuropatia Ciática/cirurgia , Alicerces Teciduais
15.
Nanomedicine ; 10(8): 1809-18, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25042134

RESUMO

Nanotube morphology has been previously applied to improve osseointegration in osteoporosis, but the osteogenic capability of the technique requires further improvements. This study aimed to investigate the effects of vacuum extraction on the loading of rhPDGF-BB on nanotube arrays as well as its effects on the osseointegration of ovariectomized (OVX) rats. More rhPDGF-BB protein particles aggregated on the nanotube surface and into the nanotube after vacuum extraction for 10 min. The immobilized protein could be slowly released for at least 14 days and still kept its biological activity. In vitro, the immobilized rhPDGF-BB enhanced cell adhesion, proliferation and osteogenic differentiation. In vivo, more rhPDGF-BB immobilized on the nanotube surface also promoted the osseointegration. These results suggest that the enhanced immobilization of rhPDGF-BB on nanotube arrays can potentially be used in the future as an implant surface modification strategy in dental and orthopedic applications in osteoporotic patients. FROM THE CLINICAL EDITOR: This study presents convincing evidence that enhanced immobilization of recombinant human PDGF-BB protein particles on nanotubes lead to improved osteogenic differentiation in an experimental system. When used as a surface modification strategy for dental or orthopedic implants, this method was able to promote osseointegration even in an osteoporotic animal model, raising the likelihood for potential future clinical applications.


Assuntos
Nanotubos/química , Osseointegração/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-sis/química , Proteínas Proto-Oncogênicas c-sis/farmacologia , Vácuo , Animais , Becaplermina , Feminino , Ovariectomia , Ratos
16.
J Craniofac Surg ; 25(5): e502-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25148645

RESUMO

Fibroblast growth factor 9 (FGF9) plays complicated and crucial roles in bone formation, and the biologic effect of FGF9 may depend on the gene dosage, developmental stage, cell type, or interactions with other cytokines. In this study, we demonstrated that FGF9 enhanced the phosphorylation of extracellular regulated protein kinases 1/2 in calvaria-derived mesenchymal cells. However, the inhibitory effect of FGF9 on the osteogenic differentiation of calvaria-derived mesenchymal cells did not depend on the phosphorylation of extracellular regulated protein kinases 1/2. Combined with the previous findings that FGF9 promotes dental pulp stem cells chondrogenesis in vitro, we suggest that FGF9 may be applied to promote chondrogenesis and inhibit osteogenesis in mesenchymal stem cells in vitro.


Assuntos
Fator 9 de Crescimento de Fibroblastos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fosfatase Alcalina/efeitos dos fármacos , Animais , Butadienos/farmacologia , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Condrogênese/efeitos dos fármacos , Colágeno Tipo I/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/efeitos dos fármacos , Meios de Cultura , Inibidores Enzimáticos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/efeitos dos fármacos , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/efeitos dos fármacos , Nitrilas/farmacologia , Osteocalcina/efeitos dos fármacos , Osteopontina/efeitos dos fármacos , Fosforilação , Crânio/citologia , Crânio/efeitos dos fármacos
17.
Dent Mater ; 40(2): 285-296, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37996303

RESUMO

OBJECTIVES: This study has developed and optimized a machine learning model to accurately predict the final colors of CAD-CAM ceramics and determine their required minimum thicknesses to cover different clinical backgrounds. METHODS: A total of 120 ceramic specimens (2 mm, 1 mm and 0.5 mm thickness; n = 10) of four CAD-CAM ceramics - IPS e.max, IPS ZirCAD, Upcera Li CAD and Upcera TT CAD - were studied. The CIELab coordinates (L*, a* and b*) of each specimen were obtained over seven different clinical backgrounds (A1, A2, A3.5, ND2, ND7, cobalt-chromium alloy (CC) and medium precious alloy (MPA)) using a digital spectrophotometer. The color difference (ΔE) and lightness difference (ΔL) results were submitted to 39 different models. The prediction results from the top-performing models were used to develop a fusion model via the Stacking integrated learning method for best-fitting prediction. The SHapley Additive exPlanation (SHAP) was performed to interpret the feature importance. RESULTS: The fusion model, which combined the ExtraTreesRegressor (ET) and XGBRegressor (XGB) models, demonstrated minimal prediction errors (R2 = 0.9) in the external testing sets. Among the investigated variables, thickness and background colors (CC and MPA) majorly influenced the final color of restoration. To achieve perfect aesthetic restoration (ΔE<2.6), at least 1.9 mm IPS ZirCAD or 1.6 mm Upcera TT CAD were required to cover the CC background, while two tested glass-ceramics did not meet the requirements even with thicknesses over 2 mm. SIGNIFICANCE: The fusion model provided a promising tool for automate decision-making in material selection with minimal thickness over various clinical background.


Assuntos
Cerâmica , Porcelana Dentária , Cor , Desenho Assistido por Computador , Ligas de Cromo , Teste de Materiais , Propriedades de Superfície
18.
Nanoscale Horiz ; 9(3): 365-383, 2024 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-38230559

RESUMO

Precision drug delivery and multimodal synergistic therapy are crucial in treating diverse ailments, such as cancer, tissue damage, and degenerative diseases. Electrodes that emit electric pulses have proven effective in enhancing molecule release and permeability in drug delivery systems. Moreover, the physiological electrical microenvironment plays a vital role in regulating biological functions and triggering action potentials in neural and muscular tissues. Due to their unique noncentrosymmetric structures, many 2D materials exhibit outstanding piezoelectric performance, generating positive and negative charges under mechanical forces. This ability facilitates precise drug targeting and ensures high stimulus responsiveness, thereby controlling cellular destinies. Additionally, the abundant active sites within piezoelectric 2D materials facilitate efficient catalysis through piezochemical coupling, offering multimodal synergistic therapeutic strategies. However, the full potential of piezoelectric 2D nanomaterials in drug delivery system design remains underexplored due to research gaps. In this context, the current applications of piezoelectric 2D materials in disease management are summarized in this review, and the development of drug delivery systems influenced by these materials is forecast.


Assuntos
Nanoestruturas , Nanoestruturas/uso terapêutico , Nanoestruturas/química , Eletricidade , Fenômenos Mecânicos , Sistemas de Liberação de Medicamentos
19.
Bioact Mater ; 35: 477-494, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38404640

RESUMO

Caries is one of the most prevalent human diseases, resulting from demineralization of tooth hard tissue caused by acids produced from bacteria, and can progress to pulpal inflammation. Filling restoration with dental resin composites (DRCs) is currently the most common treatment for caries. However, existing DRCs suffer from low fracture strength and lack comprehensive anti-caries bioactivity including remineralization, pulp protection, and anti-cariogenic bacteria effects. In this study, inspired by plant roots' ability to stabilize and improve soil, fluorinated urchin-like hydroxyapatite (FUHA) with a three-dimensional whisker structure and bioactive components of calcium, phosphorus, and fluorine was designed and synthesized by a dynamic self-assembly method. Furthermore, versatile FUHA particles with different loading fractions were used as functional fillers to fabricate methacrylate-based DRCs, where the urchin-like hydroxyapatite (UHA) filled DRCs and commercial DRCs (Z350XT and BEAUTIFIL II) served as the control groups. The results demonstrated that FUHA with 50 wt% loading in resin matrix endowed DRC (F5) with excellent physicochemical properties, dentin remineralization property, cell viability, promotion of dental pulp stem cells mineralization, and antibacterial properties. Meanwhile, F5 also presented good clinical handling and aesthetic characteristics. Therefore, structure/functional-integrated FUHA filled DRCs have potential as a promising strategy for tooth restoration and anti-caries bioactivity.

20.
Bioact Mater ; 35: 274-290, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38370865

RESUMO

The healing process of critical-sized bone defects urges for a suitable biomineralization environment. However, the unsatisfying repair outcome usually results from a disturbed intricate milieu and the lack of in situ mineralization resources. In this work, we have developed a composite hydrogel that mimics the natural bone healing processes and serves as a seedbed for bone regeneration. The oxidized silk fibroin and fibrin are incorporated as rigid geogrids, and amorphous calcium phosphate (ACP) and platelet-rich plasma serve as the fertilizers and loam, respectively. Encouragingly, the seedbed hydrogel demonstrates excellent mechanical and biomineralization properties as a stable scaffold and promotes vascularized bone regeneration in vivo. Additionally, the seedbed serves a succinate-like function via the PI3K-Akt signaling pathway and subsequently orchestrates the mitochondrial calcium uptake, further converting the exogenous ACP into endogenous ACP. Additionally, the seedbed hydrogel realizes the succession of calcium resources and promotes the evolution of the biotemplate from fibrin to collagen. Therefore, our work has established a novel silk-based hydrogel that functions as an in-situ biomineralization seedbed, providing a new insight for critical-sized bone defect regeneration.

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