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1.
Environ Res ; 252(Pt 4): 119137, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38740290

RESUMO

Enzymatic pretreatment is an effective method which can improve the anaerobic digestion (AD) efficiency of household food waste (HFW). As an alternative to expensive commercial enzymes, mixed enzymes (MEs) produced in situ from HFW by solid-state fermentation (SSF) can greatly promote the hydrolysis rate of HFW and achieve advanced anaerobic digestion (AAD) economically sustainable. In this paper, strategies for improving the efficiency of the enzyme-production process and the abundance of MEs are briefly discussed, including SSF, fungal co-cultivation, and stepwise fermentation. The feasibility of using HFW as an applicable substrate for producing MEs (amylase, protease, and lignocellulose-degrading enzymes) and its potential advantages in HFW anaerobic digestion are comprehensively illustrated. Based on the findings, an integrated AAD process of HFW pretreated with MEs produced in situ was proposed to maximise bioenergy recovery. The mass balance results showed that the total volatile solids removal rate could reach 98.56%. Moreover, the net energy output could reach 2168.62 MJ/t HFW, which is 9.79% higher than that without in situ-produced MEs and pretreatment. Finally, perspectives for further study are presented.


Assuntos
Fermentação , Anaerobiose , Eliminação de Resíduos/métodos , Estudos de Viabilidade , Hidrólise , Perda e Desperdício de Alimentos
2.
J Periodontal Res ; 59(1): 119-127, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37817319

RESUMO

BACKGROUND: Toll-like receptor 4 (TLR4)-mediated inflammatory responses are associated with diabetes and periodontitis, which are dysregulated by O-GlcNAcylation. OBJECTIVE: This study aimed to investigate the effects of O-GlcNAc transferase (OGT)-mediated TLR4 O-GlcNAcylation on the osteogenesis of periodontal ligament stem cells (PDLCs). METHODS: PDLCs were treated with high glucose (HG) to establish a cell model. Osteogenic differentiation was evaluated using western blotting, an alkaline phosphatase activity assay, and an alizarin red S staining assay. The regulation of OGT on the O-GlcNAcylation of TLR4 was analyzed using co-immunoprecipitation, immunoprecipitation, western blotting, and immunofluorescence staining. RESULTS: The results showed that HG inhibited osteogenic differentiation and promoted inflammatory response. Knockdown of OGT promoted osteogenic differentiation of HG-treated PDLCs. OGT interacted with TLR4 and increased the O-GlcNAcylation and protein levels of TLR4 in the cytomembrane of PDLCs. Moreover, silenced TLR4 reversed the effects on osteogenic differentiation induced by OGT in HG-treated PDLCs. CONCLUSION: O-GlcNAcylation of TLR4 induced by OGT suppresses osteogenic differentiation of PDLCs after HG stimulation. The findings suggest a promising strategy for treating DP.


Assuntos
Osteogênese , Receptor 4 Toll-Like , Receptor 4 Toll-Like/metabolismo , Ligamento Periodontal , Células Cultivadas , Diferenciação Celular , Células-Tronco
3.
IEEE Trans Pattern Anal Mach Intell ; 45(8): 10129-10142, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37022867

RESUMO

Recently, many advances in inverse rendering are achieved by high-dimensional lighting representations and differentiable rendering. However, multi-bounce lighting effects can hardly be handled correctly in scene editing using high-dimensional lighting representations, and light source model deviation and ambiguities exist in differentiable rendering methods. These problems limit the applications of inverse rendering. In this paper, we present a multi-bounce inverse rendering method based on Monte Carlo path tracing, to enable correct complex multi-bounce lighting effects rendering in scene editing. We propose a novel light source model that is more suitable for light source editing in indoor scenes, and design a specific neural network with corresponding disambiguation constraints to alleviate ambiguities during the inverse rendering. We evaluate our method on both synthetic and real indoor scenes through virtual object insertion, material editing, relighting tasks, and so on. The results demonstrate that our method achieves better photo-realistic quality.


Assuntos
Algoritmos , Iluminação , Iluminação/métodos , Redes Neurais de Computação , Método de Monte Carlo
4.
BMC Geriatr ; 22(1): 741, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096760

RESUMO

BACKGROUND: Although multimorbidity is a risk factor for disability, the relationship between the accumulative patterns of multimorbidity and disability remains poorly understood. The objective of this study was to identify the latent groups of multimorbidity trajectories among mid to older age adults and to examine their associations with incident disability. METHODS: We included 5,548 participants aged ≥ 45 years who participated in the China Health and Retirement Longitudinal Study from 2011 to 2018 and had no multimorbidity (≥ 2 chronic conditions) at baseline. The group-based multi-trajectory modeling was used to identify distinct trajectory groups of multimorbidity based on the latent dimensions underlying 13 chronic conditions. The association between multimorbidity trajectories and incident disability was analyzed using the generalized estimating equation model adjusting for potential confounders. RESULTS: Of the 5,548 participants included in the current analysis, 2,407 (43.39%) developed multimorbidity during the follow-up. Among participants with new-onset multimorbidity, four trajectory groups were identified according to the combination of newly diagnosed diseases: "Cardiometabolic" (N = 821, 34.11%), "Digestive-arthritic" (N = 753, 31.28%), "Cardiometabolic/Brain" (N = 618, 25.68%), and "Respiratory" (N = 215, 8.93%). Compared to participants who did not develop multimorbidity, the risk of incident disability was most significantly increased in the "Cardiometabolic/Brain" trajectory group (OR = 2.05, 95% CI: 1.55-2.70), followed by the "Cardiometabolic" (OR = 1.96, 95% CI: 1.52 -2.53) and "Digestive-arthritic" (OR = 1.70, 95% CI: 1.31-2.20) trajectory groups. CONCLUSIONS: The growing burden of multimorbidity, especially the comorbid of cardiometabolic and brain diseases, may be associated with a significantly increased risk of disability for mid to older age adults. These findings improve our understanding of multimorbidity patterns that affect the independence of living and inform the development of strategies for the primary prevention of disability.


Assuntos
Multimorbidade , Aposentadoria , Idoso , China/epidemiologia , Doença Crônica , Humanos , Estudos Longitudinais
5.
J Clin Periodontol ; 49(11): 1192-1202, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35924763

RESUMO

AIM: The role of lipids in periodontitis has not been well studied. Thus, this study aimed to explore periodontitis-associated lipid profile changes and identify differentially expressed lipid metabolites in gingival tissues. MATERIALS AND METHODS: Gingival tissues from 38 patients with periodontitis (periodontitis group) and 38 periodontally healthy individuals (control group) were collected. A ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry-based non-targeted metabolomics platform was used to identify and compare the lipid profiles of the two groups. The distribution and expression of related proteins were subsequently analysed via immunohistochemistry to further validate the identified lipids. RESULTS: Lipid profiles significantly differed between the two groups, and 20 differentially expressed lipid species were identified. Lysophosphatidylcholines (lysoPCs), diacylglycerols (DGs), and phosphatidylethanolamines (PEs) were significantly up-regulated, while triacylglycerols (TGs) were downregulated in the periodontitis group. Moreover, the staining intensity of ABHD5/CGI-58, secretory phospholipase A2 (sPLA2), and sPLA2-IIA was significantly stronger in the gingival tissues of patients with periodontitis than in those of healthy controls. CONCLUSIONS: LysoPCs, DGs, and PEs were significantly up-regulated, whereas TGs were down-regulated in gingival tissues of patients with periodontitis. Correspondingly, the immunohistochemical staining of ABHD5/CGI-58, sPLA2, and sPLA2-IIA in gingival tissues was consistent with the downstream production of lipid classes (lysoPCs, TGs, and DGs).


Assuntos
Periodontite , Fosfolipases A2 Secretórias , 1-Acilglicerol-3-Fosfato O-Aciltransferase , Diglicerídeos , Humanos , Lipidômica , Lisofosfatidilcolinas , Fosfatidiletanolaminas , Triglicerídeos
6.
Bioresour Technol ; 341: 125899, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34523558

RESUMO

Anaerobic-based processes are green and sustainable technologies for phosphorus (P) recovery from sewage sludges economically and are promising in practical application. However, the P release efficiency is always not satisfied. In this paper, the P release mechanisms (regarding to different P species) from sewage sludge using anaerobic-based processes are systematically summarized. The obstacles of P release and the updated achievements of enhancing P release from sewage sludges are analyzed and discussed. It can be concluded that different P species can release from sewage sludge via different anaerobic-based processes. Extracellular polymeric substances and excessive metal ions are the two main limiting factors to P release. Acid fermentation and anaerobic fermentation with sulfate reduction could be two promising ways, with P release efficiencies of up to 64% and 63%. Based on the summarization and discussion, perspectives on practical application of P recovery from sewage sludge using anaerobic-based processes are proposed.


Assuntos
Fósforo , Esgotos , Anaerobiose , Fermentação , Oxirredução , Eliminação de Resíduos Líquidos
7.
J Phys Chem Lett ; 12(39): 9475-9480, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34559546

RESUMO

The optical second harmonic generation (SHG) efficiency of hexagonal boron nitride (h-BN) layered materials is profoundly influenced by the symmetry properties, which has severely limited the usefulness of their SHG for nonlinear optical applications. Herein, we report on the controlled growth of large-area and continuous ultrathin h-BN films with a high density of exposed edges that show strongly enhanced SHG, owing to the breaking of inversion symmetry occurring naturally at edge sites. The large-area growth of edge-enriched BN films was accomplished through the introduction of Turing instability into a growth process that involves the liquid-gas interface self-limiting reaction between molten boron oxide (B2O3) with gaseous ammonia (NH3) at elevated temperature. Remarkably, the edge-enriched BN films give rise to a SHG response up to nearly 3 orders of magnitude higher than that of the smooth BN films prepared through the same growth approach but with different growth parameters.

8.
Sci Total Environ ; 786: 147437, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-33971595

RESUMO

Phosphorus recovery from municipal sewage sludge is a promising way to alleviate the shortage of phosphorus resources. However, the recovery efficiency and cost depend greatly on phosphorus species and fractions in different sewage sludges, i.e., waste activated sludge and chemically enhanced primary sludge. In this review, the phosphorous (sub-)species and fractions in waste activated sludge and chemically enhanced primary sludge are systematically overviewed and compared. The factors affecting phosphorus fractions, including wastewater treatment process, as well as sludge treatment methods and conditions are summarized and discussed; it is found that phosphorus removal method and sludge treatment process are the dominant factors. The characterization methods of phosphorus species and fractions in sewage sludge are reviewed; non-destructive extraction of poly-P and microscopic IP characterization need more attention. Anaerobic fermentation is the preferable solution to achieve advanced phosphorus release both from waste activated sludge and chemically enhanced primary sludge, because it can make phosphorus species and fractions more suitable for recovery. A post low strength acid extraction after anaerobic fermentation is recommended to facilitate phosphorous release and improve the total recovery rate.

9.
J Trauma Acute Care Surg ; 90(6): 1032-1039, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34016926

RESUMO

INTRODUCTION: Previously, in a murine model of blunt thoracic trauma, we provided evidence of primary pulmonary thrombosis associated with increased expression of the cell adhesion molecule, P-selectin. In this study, mice are treated with P-selectin blocking antibody after injury to investigate the clinical viability of this antibody for the prevention of pulmonary thrombosis. In addition, viscoelastic testing is performed to investigate if P-selectin inhibition has a detrimental impact on normal hemostasis. METHODS: A murine model of thoracic trauma was used. Mice were divided into sham control and experimental injury groups. Thirty minutes after trauma, mice were treated with the following: P-selectin blocking antibody, isotype control antibody, low-dose heparin, high-dose heparin, or normal saline. At 90 minutes, whole blood was collected for characterization of coagulation by viscoelastic coagulation monitor (VCM Vet; Entegrion, Durham, NC). Mean clotting time, clot formation time, clot kinetics (α angle), and maximum clot firmness were compared between each treatment group. RESULTS: Mice that received P-selectin antibody 30 minutes after blunt thoracic trauma had four- to fivefold less (p < 0.001) arterial fibrin accumulation than those that received the isotype control. In both sham and trauma groups, compared with vehicle (normal saline) alone, no statistical difference was noted in any coagulation parameters after injection with P-selectin antibody, isotype control, or low-dose heparin. In addition, blinded histopathological evaluation yielded no difference in hemorrhage scores between injured mice treated with P-selectin blocking antibody and those treated with isotype antibody control. CONCLUSION: This study supports the clinical use of P-selectin blocking antibody for the prevention of pulmonary thrombosis by confirming its efficacy when given after a blunt thoracic trauma. In addition, we demonstrated that the administration of P-selectin antibody does not adversely affect systemic coagulation as measured by viscoelastic testing, suggesting that P-selectin antibody can be safely given during the acute posttraumatic period.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Selectina-P/antagonistas & inibidores , Embolia Pulmonar/prevenção & controle , Traumatismos Torácicos/complicações , Ferimentos não Penetrantes/complicações , Animais , Coagulação Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Heparina/administração & dosagem , Humanos , Masculino , Camundongos , Embolia Pulmonar/sangue , Embolia Pulmonar/etiologia , Traumatismos Torácicos/sangue , Traumatismos Torácicos/terapia , Ferimentos não Penetrantes/sangue , Ferimentos não Penetrantes/terapia
10.
Front Pharmacol ; 12: 633353, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679417

RESUMO

Growing number of studies regarding the role of circRNAs in the development of various diseases have emerged in recent years, but the role of circRNAs in periodontitis pathogenesis remains obscure. Human periodontal ligament stem cells (hPDLSCs) play a critical role in periodontal remodeling, regeneration and repair processes, and their regenerative capacity could be prohibited in local periodontal inflammatory microenvironment. Herein, we sought to uncover the molecular mechanisms of periodontitis pathogenesis by investigating the role of circMAP3K11 (hsa_circ_002284) for regenerative capacity of hPDLSCs under an inflammatory condition. The hPDLSCs isolated from periodontitis patients were used as a cell model of inflammatory microenvironment to study the effect of the circMAP3K11/miR-511-3p/TLR4 axis on the proliferation, apoptosis and migration of hPDLSCs under inflammatory conditions. Compared to the periodontal tissues from normal subjects, those from periodontitis patients exhibited higher expression levels of circMAP3K11 and TLR4, and lower expression level of miR-511-3p. Both the expressions of circMAP3K11 and TLR4 were negatively correlated with the expressions of miR-511-3p in periodontitis. In vitro studies demonstrated that circMAP3K11 is capable of enhancing hPDLSCs proliferation and migration, and reducing the apoptosis of hPDLSCs. We also found that circMAP3K11 could up-regulate the expression of transcription factors that are closely related to periodontal regeneration (Runx2, OSX, ATF4, and BSP). RT-PCR and western blot showed that the inhibitory role of miR-511-3p on TLR4 expression could be reversed by circMAP3K11, which was in line with the results of bioinformatics tools and luciferase reporter assay. Meanwhile, both in vitro and in vivo studies indicated that circMAP3K11 could reverse the effects of miR-511-3p in periodontitis, which further confirmed that circMAP3K11 functioned as a 'sponge' of miR-511-3p to positively regulate the expression of TLR4. Taken together, our study preliminarily uncovered a circMAP3K11/miR-511-3p/TLR4 axis that regulates the function of hPDLSCs in periodontitis, providing novel insight and scientific base in the treatment of periodontal tissue regeneration based on stem cells.

11.
J Oleo Sci ; 69(10): 1191-1198, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32908091

RESUMO

The kinetics of catalytic transfer hydrogenation (CTH) of low-erucic-acid rapeseed oil using ammonium formate as a hydrogen donor over a Ni-Ag0.15/SBA15 catalyst were studied. Then, a kinetic model for the hydrogenation of low-erucic-acid rapeseed oil was established, and it was found that the reaction rate constants of hydrogenations of 9c-18:1 and 12c-18:1 oleic acid were 0.1262 and 0.0148, and the catalytic selectivity of linoleic acid was 2.04. For the catalyst loading of 0.23%, the hydrogenation temperature was 80°C, the ammonium formate concentration was 0.32 mol/50 mL, and the low-erucic-acid rapeseed oil was hydrogenated in 90 min; it was also found that the iodine value of low-erucic-acid rapeseed oil was 80 g I2/100 g, the oleic acid content was 65%, and the trans fatty acids (TFAs) content was only 6.7%. Therefore, CTH may be widely used in the modification of oils and fats.


Assuntos
Ácidos Erúcicos , Cinética , Níquel/química , Óleo de Brassica napus/química , Prata/química , Catálise , Formiatos/química , Temperatura Alta , Hidrogenação , Iodo/análise , Ácido Linoleico/análise , Ácido Linoleico/química , Ácido Oleico/análise , Ácido Oleico/química , Ácidos Graxos trans/análise
12.
Adv Sci (Weinh) ; 6(12): 1900310, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31380169

RESUMO

Recent achievements in semiconductor surface-enhanced Raman scattering (SERS) substrates have greatly expanded the application of SERS technique in various fields. However, exploring novel ultra-sensitive semiconductor SERS materials is a high-priority task. Here, a new semiconductor SERS-active substrate, Ta2O5, is developed and an important strategy, the "coupled resonance" effect, is presented, to optimize the SERS performance of semiconductor materials by energy band engineering. The optimized Mo-doped Ta2O5 substrate exhibits a remarkable SERS sensitivity with an enhancement factor of 2.2 × 107 and a very low detection limit of 9 × 10-9 m for methyl violet (MV) molecules, demonstrating one of the highest sensitivities among those reported for semiconductor SERS substrates. This remarkable enhancement can be attributed to the synergistic resonance enhancement of three components under 532 nm laser excitation: i) MV molecular resonance, ii) photoinduced charge transfer resonance between MV molecules and Ta2O5 nanorods, and iii) electromagnetic enhancement around the "gap" and "tip" of anisotropic Ta2O5 nanorods. Furthermore, it is discovered that the concomitant photoinduced degradation of the probed molecules in the time-scale of SERS detection is a non-negligible factor that limits the SERS performance of semiconductors with photocatalytic activity.

13.
Int J Mol Med ; 43(6): 2341-2351, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31017254

RESUMO

Toll­like receptor 4 (TLR4) is a transmembrane receptor responsible for the activation of a number of signal transduction pathways. Despite its involvement in inflammatory processes, the regulation of TLR4 signaling in human periodontal ligament stem cells (hPDLSCs) under inflammatory conditions remains to be fully elucidated. The present study aimed to clarify the regulatory mechanisms of the TLR4 signaling pathway and its role in the differentiation of hPDLSCs under inflammatory conditions. hPDLSCs from the periodontal tissues of healthy subjects and patients with periodontitis were identified by analyzing their cell surface marker molecules, and their osteogenic and adipogenic differentiation abilities. To determine the effect of TLR4 signaling on osteogenic and adipogenic differentiation under inflammatory conditions, cells were challenged with TLR4 agonist and antagonist under pluripotent differentiation conditions. Cell proliferation, apoptosis and migration were then determined using appropriate methods. The alkaline phosphatase (ALP) activity, Alizarin Red staining, Oil red O staining and relative gene and protein levels expression were also determined. The results showed that lipopolysaccharide (LPS)­induced inflammation inhibited cell proliferation and migration, promoted cell apoptosis and affected the cell cycle. Under inflammatory conditions, the activation of TLR4 decreased the activity of ALP and the expression of osteogenic markers, including osteocalcin, Runt­related transcription factor 2 and collagen I, compared with the control group, but increased the expression of adipogenesis­related genes poly (ADP­ribose) polymerase Î³ and lipoprotein lipase. The activation of TLR4 also induced the expression of proinflammatory cytokines interleukin­1ß, tumor necrosis factor­α, nuclear factor­κBP65 and TLR4, compared with that in the control group and the TLR4 antagonist group. The findings showed that LPS­induced upregulation of the TLR4 signaling pathway inhibited osteogenic differentiation and induced adipogenesis of the hPDLSCs under inflammatory conditions. The present study provided a novel understanding of the physiopathology of periodontitis, and a novel avenue for targeted treatments based on stem cell regeneration.


Assuntos
Inflamação/imunologia , Lipopolissacarídeos/imunologia , Osteogênese , Ligamento Periodontal/citologia , Ligamento Periodontal/imunologia , Receptor 4 Toll-Like/imunologia , Apoptose , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Inflamação/patologia , Ligamento Periodontal/patologia , Transdução de Sinais
14.
ACS Omega ; 3(9): 11562-11568, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31459256

RESUMO

A series of polymer solar cells (PSCs) were prepared with different solvent additive 1-chloronaphthalene (CN) doping volume ratio to adjust the phase separation of active layers. The optimized PSCs exhibit a power conversion efficiency (PCE) of 8.09%, along with an open-circuit voltage of 1.01 V, a short circuit current density of 13.64 mA cm-2, and a fill factor of 58.70%. All the key photovoltaic parameters of PSCs can be simultaneously increased by incorporating 1.0 vol % CN in blend solutions due to the optimized phase separation of active layers assisted by the volatilization of CN. Over 24% PCE improvement can be obtained by incorporating 1.0 vol % CN, indicating that the dynamic process of film forming should play the vital role in determining the performance of PSCs.

15.
In Vitro Cell Dev Biol Anim ; 52(7): 757-71, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27251156

RESUMO

Bone marrow-derived mesenchymal stem cells (BM-MSCs) have been recognized as a new strategy for maxillary sinus floor elevation. However, little is known concerning the effect of the biomechanical pressure (i.e., sinus pressure, masticatory pressure, and respiration) on the differentiation of BM-MSCs and the formation of new bone during maxillary sinus floor elevation. The differentiation of BM-MSCs into osteoblasts was examined in vitro under cyclic compressive pressure using the Flexcell® pressure system, and by immunohistochemical analysis, qRT-PCR, and Western blot. Micro-CT was used to detect bone formation and allow image reconstruction of the entire maxillary sinus floor elevation area. Differentiation of BM-MSCs into osteoblasts was significantly increased under cyclic compressive pressure. The formation of new bone was enhanced after implantation of the pressured complex of BM-MSCs and Bio-Oss during maxillary sinus floor elevation. The pressured complex of BM-MSCs and Bio-Oss promoted new bone formation and maturation in the rabbit maxillary sinus. Stem cell therapy combined with this tissue engineering technique could be effectively used in maxillary sinus elevation and bone regeneration.


Assuntos
Seio Maxilar/crescimento & desenvolvimento , Transplante de Células-Tronco Mesenquimais , Osteoblastos/citologia , Osteogênese , Animais , Células da Medula Óssea/citologia , Diferenciação Celular/genética , Humanos , Seio Maxilar/efeitos dos fármacos , Células-Tronco Mesenquimais , Minerais/administração & dosagem , Osteoblastos/efeitos dos fármacos , Coelhos , Levantamento do Assoalho do Seio Maxilar/métodos
16.
J Oral Maxillofac Surg ; 72(6): 1084-92, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24576438

RESUMO

PURPOSE: To compare the potential of tissue-engineered bone derived from different stem cell sources for canine maxillary sinus augmentation. MATERIALS AND METHODS: Bilateral maxillary sinus floor augmentations were performed in 6 beagles and were randomly repaired with 3 graft types: Bio-Oss granules alone (n = 4; group A), a complex of osteoblasts derived from bone marrow mesenchymal stem cells (BMMSCs) and Bio-Oss (n = 4; group B), and a complex of osteoblasts derived from periodontal ligament stem cells (PDLSCs) and Bio-Oss (n = 4; group C). After 12 weeks, fluorescent labeling, maxillofacial computed tomography, scanning electron microscopy, and histologic and histomorphometric analyses were used to evaluate new bone deposition, mineralization, and remodeling in the augmented area. RESULTS: The osteogenic capacity was greater in groups B and C than in group A. The level tended to be higher in group C than in group B; however, the difference was not statistically significant. CONCLUSIONS: Seeding of PDLSCs or BMMSCs onto Bio-Oss can promote bone formation and mineralization and maintain the maximum volume of the augmented maxillary sinus. These tissue-engineered bone complexes might be a good option for augmentation of the maxillary sinus in edentulous patients.


Assuntos
Regeneração Óssea/fisiologia , Levantamento do Assoalho do Seio Maxilar/métodos , Células-Tronco/fisiologia , Engenharia Tecidual/métodos , Animais , Autoenxertos/transplante , Remodelação Óssea/fisiologia , Substitutos Ósseos/uso terapêutico , Calcificação Fisiológica/fisiologia , Técnicas de Cultura de Células , Células Cultivadas , Colágeno Tipo I/análise , Meios de Cultura , Cães , Corantes Fluorescentes , Sialoproteína de Ligação à Integrina/análise , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Microscopia Eletrônica de Varredura , Minerais/uso terapêutico , Modelos Animais , Osteoblastos/fisiologia , Osteocalcina/análise , Osteogênese/fisiologia , Ligamento Periodontal/citologia , Distribuição Aleatória , Tomografia Computadorizada por Raios X/métodos
17.
J Biomater Appl ; 29(2): 243-253, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24487130

RESUMO

The aim of this study was to compare the osteogenic effects of periodontal ligament stem cells (PDLSCs) versus bone marrow mesenchymal stem cells (BMMSCs) in combination with Bio-Oss scaffolds on subcutaneous and critical-size defects in the immunodeficient rat calvarium. PDLSCs and BMMSCs were obtained from the same canine donor. Twenty-four rats were randomly assigned to one of four experimental groups (n = 6 each): group A (no-graft negative control), group B (Bio-Oss positive control), group C (BMMSC/Bio-Oss test group), and group D (PDLSC/Bio-Oss test group). Eight weeks post-transplantation, ectopic and in situ bone regeneration was evaluated by micro-computed tomography (µ-CT), histology, histomorphometry, and immunohistochemistry. The stem cell/Bio-Oss constructs were significantly superior to the controls in terms of their ability to promote osteogenesis (p < 0.01), while the PDLSC/Bio-Oss construct tended to be superior to the BMMSC/Bio-Oss construct. Thus, engineered stem cell/Bio-Oss complexes can successfully reconstruct critical-size defects in rats, and PDLSCs and BMMSCs are both suitable as seed cells.

18.
Mol Med Rep ; 9(1): 235-42, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24173502

RESUMO

Identifying a reliable and effective cytokine or growth factor group has been the focus of stem cell osteogenic induction studies. Concentrated growth factors (CGFs) as the novel generation of platelet concentrate products, appear to exhibit a superior clinical and biotechnological application potential, however, there are few studies that have demonstrated this effect. This study investigated the proliferation and differentiation of periodontal ligament stem cells (PDLSCs) co­cultured with CGFs. The rate of proliferation was analyzed by cell counting and an MTT assay. Mineralization nodule counts, alkaline phosphatase activity detection, qPCR, western blot analysis and immunohistochemistry were used to analyze mineralization effects. The results showed that CGF significantly promoted the proliferation of PDLSCs, and exhibited a dose­dependent effect on the activation and differentiation of the stem cells. The application of CGF on PDLSC proliferation and osteoinduction may offer numerous clinical and biotechnological application strategies.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Ligamento Periodontal/citologia , Células-Tronco/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cães , Sialoproteína de Ligação à Integrina/genética , Sialoproteína de Ligação à Integrina/metabolismo , Osteocalcina/genética , Osteocalcina/metabolismo , Células-Tronco/citologia
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