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The assembly of bacterial communities in the rhizosphere is well-documented and plays a crucial role in supporting plant performance. However, we have limited knowledge of how plant rhizosphere determines the assembly of protistan predators and whether the potential associations between protistan predators and bacterial communities shift due to rhizosphere selection. To address this, we examined bacterial and protistan taxa from 443 agricultural soil samples including bulk and rhizosphere soils. Our results presented distinct patterns of bacteria and protistan predators in rhizosphere microbiome assembly. Community assembly of protistan predators was determined by a stochastic process in the rhizosphere and the diversity of protistan predators was reduced in the rhizosphere compared to bulk soils, these may be attributed to the indirect impacts from the altered bacterial communities that showed deterministic process assembly in the rhizosphere. Interestingly, we observed that the plant rhizosphere facilitates more close interrelationships between protistan predators and bacterial communities, which might promote a healthy rhizosphere microbial community for plant growth. Overall, our findings indicate that the potential predator-prey relationships within the microbiome, mediated by plant rhizosphere, might contribute to plant performance in agricultural ecosystems.
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Microbiota , Rizosfera , Microbiología del Suelo , Raíces de Plantas/microbiología , Bacterias/genética , Suelo , PlantasRESUMEN
The prevalence of quantum crosstalk in current quantum devices poses challenges for achieving high-fidelity quantum logic operations and reliable quantum processing. Through quantum control theory, we develop an analytical condition for achieving crosstalk-robust single-qubit control of multiqubit systems. We examine the effects of quantum crosstalk via a cumulant expansion and develop a condition to suppress the leading order contributions to the dynamics. The efficacy of the condition is illustrated in the domains of quantum state preservation and noise characterization through the development of crosstalk-robust dynamical decoupling and quantum noise spectroscopy (QNS) protocols. Using the IBM Quantum Experience, crosstalk-robust state preservation is demonstrated on 27 qubits, where up to a 3.5× improvement in coherence decay is observed for single-qubit product and multipartite entangled states. Through the use of noise injection, we demonstrate crosstalk-robust dephasing QNS on a seven qubit processor, where a 10^{4} improvement in reconstruction accuracy over alternative protocols is found. Together, these experiments highlight the significant impact the crosstalk suppression condition can have on improving multiqubit characterization and control on current quantum devices.
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INTRODUCTION: This study aimed to investigate the effects of estrogen on root repair after orthodontically induced root resorption. METHODS: Seventy-two 6-week-old female Wistar rats were randomly divided into 3 groups: ovariectomy only (OVX), ovariectomy plus estradiol injection (OVX + E2), and sham operation (control). E2 was administrated to all the experimental animals after the establishment of the root repair model. One-way analysis of variance with the Tukey post-hoc test was used to analyze the experimental results. RESULTS: Micro-computed tomography and hematoxylin and eosin staining showed that the total volumes of resorption lacunae were significantly smaller in the control and OVX + E2 groups than those in the OVX group. Alkaline phosphatase and tartrate-resistant acid phosphatase stainings suggested that the cementoblastic activities and the amount of new cementum formation were inhibited while the activities of osteoclasts were obvious in the OVX group. The immunohistochemistry stainings revealed that the osteoprotegerin to receptor activator of nuclear factor-кB ligand ratio and the phosphorylated extracellular signal-regulated kinases to extracellular signal-regulated kinases ratio of the control and OVX + E2 groups were significantly greater than those of the OVX group. CONCLUSIONS: These findings demonstrated that estrogen administration might be a solution to reduce orthodontically induced root resorption through the activation of extracellular signal-regulated kinase-1/2 pathway and enhancement of cementogenesis.
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Resorción Radicular , Animales , Estrógenos , Femenino , Osteoclastos , Ovariectomía , Ratas , Ratas Wistar , Microtomografía por Rayos XRESUMEN
INTRODUCTION: The aim of this study was to investigate the effect of lactoferrin (LF) on bone resorption of rats' midpalatal sutures during rapid palatal expansion. METHODS: Sixty male 5-week-old Wistar rats were randomly divided into 3 groups: expansion only (EO), expansion plus LF (E + LF), and sham device (control). RESULTS: Microcomputed tomography showed that the bone volume/tissue volume ratio and the relative bone mineral density of the suture bone were significantly increased in the E + LF group compared with the EO group. Histochemical staining suggested that the activity of osteoblast-like cells and the amount of new bone formation were stimulated in the E + LF group whereas the activity of osteoclasts showed no obvious difference between groups. On the other hand, the immunohistochemical and the real-time polymerase chain reaction results showed that the expressions of receptor activator of nuclear factor kappa B ligand and osteoprotegerin had no significant difference between the EO and E + LF groups. CONCLUSIONS: These findings demonstrated that LF could stimulate bone volume and bone density in midpalatal sutures during the suture remodeling process under tensile force. However, this enhancement effect was not caused by the reduction of bone resorption.
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Resorción Ósea/tratamiento farmacológico , Lactoferrina/farmacología , Técnica de Expansión Palatina , Paladar Duro/efectos de los fármacos , Animales , Suturas Craneales , Masculino , Distribución Aleatoria , Ratas , Ratas Wistar , Factores de TiempoRESUMEN
Estrogen has been well recognized as a key factor in the homeostasis of bone and periodontal tissue, but the way it regulates the activities of cementoblasts, the cell population maintaining cementum has not been fully understood. In this study, we examined the expression of estrogen receptor in OCCM-30 cells and the effect of 17ß-estradiol (E2) on the proliferation and differentiation of OCCM-30 cells. We found that both estrogen receptor α and ß were expressed in OCCM-30 cells. E2 exerted no significant influence on the proliferation of OCCM-30 cells, but inhibited the transcription and translation of BSP and Runx2 in the early phase of osteogenic induction except the BSP mRNA. Afterwards in the late phase of osteogenic induction, E2 enhanced the transcription and translation of BSP and Runx2 and promoted the calcium deposition. In addition, the expression level of Notch1, NICD and Hey1 mRNAs responded to exogenous E2 in a pattern similar to that of the osteoblastic markers. DAPT could attenuate the effect of E2 on the expression of osteoblastic markers. These findings indicated that E2 might regulate the differentiation of cementoblasts via Notch signaling.
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Diferenciación Celular/efectos de los fármacos , Cemento Dental/efectos de los fármacos , Estradiol/farmacología , Receptores Notch/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Línea Celular Transformada , Proliferación Celular/efectos de los fármacos , Cemento Dental/citología , Cemento Dental/metabolismo , Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , RatonesRESUMEN
Human dental pulp stem cells (hDPSCs) show significant potential for exploitation in novel regeneration strategies, although lack of understanding of their responses to bacterial challenge constrains their application. The present study aimed to investigate whether lipopolysaccharide (LPS), the major pathogenic factor of Gram-negative bacteria, regulates the differentiation of hDPSCs and which intracellular signaling pathways may be involved. LPS treatment significantly promoted the differentiation of hDPSCs demonstrable by increased mineralized nodule formation and mRNA expression of several odontoblastic markers in a dose-dependent manner. While inhibition of TLR4, p38, and ERK signaling markedly antagonized LPS-mediated differentiation of hDPSCs. The inhibition of JNK and NF-κB signaling had no detectable effect on LPS activation of hDPSCs. LPS stimulation resulted in phosphorylation of NF-κB p65, IκB-α, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) in DPSCs in a time-dependent manner, which was markedly suppressed by their specific inhibitors, respectively. Data demonstrated that LPS promoted odontoblastic differentiation of hDPSCs via TLR4, ERK, and P38 MAPK signaling pathways, but not NF-κB signaling.
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Diferenciación Celular/efectos de los fármacos , Pulpa Dental/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Células Madre/citología , Pulpa Dental/citología , Humanos , Lipopolisacáridos/toxicidad , FN-kappa B/metabolismo , Odontoblastos/citología , Odontoblastos/efectos de los fármacos , Células Madre/efectos de los fármacos , Células Madre/metabolismo , Receptor Toll-Like 4/metabolismoRESUMEN
How to prescribe traction on boundary surface is still an open question in peridynamics. This problem is investigated in this paper. Through introducing the induced body force defined by boundary traction, the Silling's peridynamic motion equation is extended to a new formulation called the traction-associated peridynamic motion equation, which is verified to be compatible with the conservation laws of linear momentum and angular momentum. The energy conservation equation derived from the traction-associated peridynamic motion equation has the same form as that in the original peridynamics advanced by Silling. Therefore, the constitutive models of the original peridynamics can be directly applied to the traction-associated peridynamic motion equation. Some benchmark examples in the plane stress problems are calculated. The numerical solutions agree well with the classical elasticity solutions, and the volume correction and the surface correction are no longer needed in the numerical algorithm. These results show that the traction-associated peridynamic motion equation not only retains all advantages of the original peridynamics, but also can conveniently deal with the complex traction boundary conditions.
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Odontoblasts are the first-line defense cells against invading microorganisms. Toll-like receptors (TLRs) play a crucial role in innate immunity, and TLR9 is involved in the recognition of microbial DNA. This study aimed to investigate whether odontoblasts can respond to CpG DNA and to determine the intracellular signaling pathways triggered by CpG DNA. We found that the mouse odontoblast-like cell line MDPC-23 constitutively expressed TLR9. Exposure to CpG ODN induced a potent proinflammatory response based on an increase of IL-6 and TNF-alpha expression. Pretreatment with an inhibitory MyD88 peptide or a specific inhibitor for TLR9, NF-kappaB or IkappaBalpha markedly inhibited CpG ODN-induced IL-6 and TNF-alpha expression. Moreover, the CpG ODN-mediated increase of kappaB-luciferase activity in MDPC-23 cells was suppressed by the overexpression of dominant negative mutants of TLR9, MyD88 and IkappaBalpha, but not by the dominant negative mutant of TLR4. This result suggests a possible role for the CpG DNA-mediated immune response in odontoblasts and indicates that TLR9, MyD88 and NF-kappaB are involved in this process.
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Islas de CpG/inmunología , ADN Bacteriano/inmunología , Factor 88 de Diferenciación Mieloide/metabolismo , FN-kappa B/metabolismo , Odontoblastos/inmunología , Receptor Toll-Like 9/metabolismo , Animales , Línea Celular , Citocinas/biosíntesis , Ratones , Odontoblastos/efectos de los fármacos , Oligodesoxirribonucleótidos/inmunología , Oligodesoxirribonucleótidos/farmacologíaRESUMEN
BACKGROUND: Increasing evidence indicates that hypertension in pregnancy plays a key role in cardiovascular disease. However, the correlation between blood pressure (BP) and proteinuria as well as renal function in the puerperium has not been established. PATIENTS: We evaluated the estimated glomerular filtration rate (eGFR) and 24-h urine total protein excretion (TPE) during the second postpartum week in 852 pregnant women with normal BPs and 114 pre-eclamptic women with BPs > or =140/90 mmHg. The 852 pregnant women with normal BPs were divided into two groups based on the mean arterial pressure (MAP): 684 subjects with an MAP<90 mmHg and 168 subjects with an MAP> or =90 mmHg. RESULTS: The eGFR was significantly decreased in pre-eclamptic women (112+/-41 ml/min/1.73 m(2)) compared with healthy women with an MAP<90 mmHg (131+/-35 ml/min/1.73 m(2), p<0.01) and an MAP> or =90 mmHg (128+/-34 ml/min/1.73 m(2), p<0.01), while the TPE was significantly increased compared with healthy women with an MAP<90 mmHg and an MAP> or =90 mmHg (1790+/-1422 vs 124+/-148 and 255+/-427 mg/24 h, respectively; p<0.001). Although the eGFR did not reveal a difference between the two groups of healthy women (131+/-35 vs 128+/-34 ml/min/1.73 m(2), p>0.05), the TPE was significantly higher in subjects with an MAP> or =90 mmHg than in subjects with an MAP<90 mmHg (255+/-427 vs 124+/-148 mg, p=0.004). CONCLUSIONS: Pre-eclampsia induces significant renal injury characterized by an elevation of TPE and a reduction in GFR. BP is closely related to urinary protein excretion, even in healthy women (BP <140/90 mmHg) in the puerperium.
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Presión Sanguínea/fisiología , Riñón/fisiopatología , Periodo Posparto/orina , Proteinuria/fisiopatología , Adulto , Femenino , Tasa de Filtración Glomerular , Humanos , Pruebas de Función Renal , Periodo Posparto/fisiología , Embarazo , Estudios RetrospectivosRESUMEN
PURPOSE: To evaluate the clinical effectiveness of two different one-step self-etching adhesives. METHODS: Two single-step self-etching adhesive systems, Clearfil Tri-S Bond and G-Bond, were evaluated. As a control, a two-step self-etching adhesive system, Clearfil SE Bond, was used. The teeth to be restored were randomly assigned. The resin composite used to restore the teeth was Clearfil AP-X. The three adhesive systems were evaluated by Modified USPHS at baseline, 3 months, 6 months, and 12 months. The evaluation consisted of retention rate, color match, marginal discoloration (interfacial staining), marginal adaptation (integrity), wear, post-operative sensitivity, caries recurrence, and other failures. Changes over time and across groups were evaluated statistically using generalized estimating equations. RESULTS: During the 12-month study period, no statistical differences were observed among the three groups (P > 0.05) in retention rate, color match, marginal discoloration (interfacial staining), marginal adaptation (integrity). No wear, post-operative sensitivity, caries recurrence, or other failures were detected in any groups. The two one-step self-etching adhesives tested showed good clinical performance at the end of 12 months.
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Restauración Dental Permanente/métodos , Recubrimientos Dentinarios/química , Cuello del Diente/patología , Desgaste de los Dientes/terapia , Adulto , Color , Resinas Compuestas/química , Recubrimiento Dental Adhesivo , Caries Dental/etiología , Adaptación Marginal Dental , Retención de Prótesis Dentales , Fracaso de la Restauración Dental , Alisadura de la Restauración Dental , Estudios de Seguimiento , Humanos , Ensayo de Materiales , Metacrilatos/química , Persona de Mediana Edad , Recurrencia , Cementos de Resina/químicaRESUMEN
Dendritic cells (DC) are specialized cells that capture and present antigen to T cells. Recent advances have been made in understanding their origin, heterogeneity, and the signals that induce their migration and maturation resident microglia are antigen-presenting cells (APC) involved in stimulation or reactivation of CNS-targeted T cells. Generation of DC from microglia, as demonstrated ex vivo, may support GM-CSF-driven differentiation of brain DC from local, likely, microglial progenitors. Here, we report the establishment of long-term cultures of rat ecto-mesenchymal stem cells (EMSCs) using specific supplemented media for induction. These EMSCs share some morphological characteristics and the allostimulatory capacity of classical DCs, and when transplanted into the brain using a rat glioma model survive within the cortex, and are morphologically and phenotypically similar to microglia over 7 days. Our findings related to the development and differentiation of microglial progenitors support the view that microglia are derived prenatally from mesodermal progenitors that are distinct from monocytes.
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Células Presentadoras de Antígenos/fisiología , Diferenciación Celular/fisiología , Células Dendríticas/inmunología , Células Madre Mesenquimatosas/citología , Células Madre Pluripotentes/citología , Animales , Células de la Médula Ósea/citología , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Células Cultivadas , Medios de Cultivo/química , Células Dendríticas/ultraestructura , Embrión de Mamíferos/citología , Femenino , Glioma/patología , Inmunohistoquímica , Trasplante de Células Madre Mesenquimatosas , Trasplante de Neoplasias , Embarazo , Ratas , Ratas Sprague-Dawley , Trasplante HomólogoRESUMEN
INTRODUCTION: Odontoblasts play an important role in post-developmental control of mineralization in response to external stimuli in the tooth. The present study investigated whether lipopolysaccharide (LPS), a major bacterial cell wall component, influenced mineralization in a murine odontoblast-like cell (OLC) line and the related intracellular signaling pathways involved. METHODS: Alizarin red S staining was used to assess mineralized nodule formation in OLCs in response to LPS. The effects of LPS on gene expression of odontoblastic markers were investigated by using quantitative real-time reverse-transcriptase polymerase chain reaction. The potential involvement of toll-like receptor 4 (TLR4), nuclear factor kappa B (NF-κB), mitogen-activated protein kinase (MAPK), or phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways in the mineralized nodule formation, and mRNA expression of several odontoblastic markers of OLCs induced by LPS was assessed by using alizarin red S staining and quantitative real-time reverse-transcriptase polymerase chain reaction. Moreover, LPS stimulation resulted in phosphorylation of protein that was determined by Western blot analysis. RESULTS: OLCs showed reduced mineralized nodule formation and several odontoblastic markers expression in response to LPS exposure. Furthermore, inhibition of TLR4, extracellular signal-regulated kinase (ERK), and PI3K/Akt signaling noticeably antagonized LPS-mediated mineralization in OLCs. However, p38 MAPK, c-Jun N-terminal kinase, and NF-κB signaling inhibitors did not affect LPS-mediated mineralization in OLCs. Notably, LPS treatment resulted in a time-dependent phosphorylation of ERK and PI3K/Akt in OLCs, which was abrogated by their specific inhibitors. CONCLUSIONS: LPS decreased mineralization in OLCs via TLR4, ERK MAPK, and PI3K/Akt signaling pathways, but not p38, c-Jun N-terminal kinase, or NF-κB signaling.
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Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Lipopolisacáridos/farmacología , Sistema de Señalización de MAP Quinasas/fisiología , Odontoblastos/efectos de los fármacos , Fosfatidilinositol 3-Quinasa/metabolismo , Animales , Línea Celular , Ratones , Odontoblastos/metabolismo , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 4/metabolismoRESUMEN
INTRODUCTION: Lipopolysaccharide (LPS) has been implicated in mesenchymal stem cell differentiation processes. Wnt5a, one of the "non-canonical" Wnt family members, is important in signaling stem cell differentiation and in the inflammatory responses of immune cells. Here we studied whether LPS can regulate the expression of Wnt5a in human dental pulp stem cells (hDPSCs) and investigated the intracellular signaling pathways activated by LPS. METHODS: Wnt5a mRNA and protein expression changes in hDPSCs were investigated by real-time polymerase chain reaction analysis and enzyme-linked immunosorbent assay. In addition, real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and luciferase activity assays were used to determine whether toll-like receptor 4 (TLR4), myeloid differentiating factor 88 (MyD88), nuclear factor kappa B (NF-kB), or the phosphatidylinositol 3-OH kinase (PI3K)/AKT pathways are involved in LPS-induced Wnt5a expression. The activation of PI3K and AKT in hDPSCs was measured by Western blot analysis. RESULTS: Wnt5a mRNA and protein expression was rapidly increased in response to LPS in a time- and dose-dependent manner. LPS-induced Wnt5a expression was effectively attenuated by administration of a TLR4 neutralizing antibody, MyD88 inhibitory peptide, PI3-kinase inhibitors (LY294002 and wortmannin), an AKT inhibitor, or NF-κB inhibitor (pyrrolidine dithiocarbamate), IκBa phosphorylation inhibitor (Bay 117082), or IκB protease inhibitor (L-1-tosylamido-2-phenylethyl chloromethyl ketone). Treatment of hDPSCs with LPS activated PI3-kinase (p85) and AKT signaling in a time-dependent manner. Moreover, LPS-mediated increases in κB-luciferase activity were diminished by the overexpression of dominant negative mutants of TLR4, MyD88, p85, AKT, and IκBa. CONCLUSIONS: These results demonstrated that LPS-induced Wnt5a expression was mediated through the TLR4/MyD88/PI3-kinase/AKT pathway, which then initiated NF-κB activation in hDPSCs.
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Pulpa Dental/citología , Lipopolisacáridos/farmacología , Factor 88 de Diferenciación Mieloide/efectos de los fármacos , FN-kappa B/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/efectos de los fármacos , Proteínas Proto-Oncogénicas/efectos de los fármacos , Células Madre/efectos de los fármacos , Receptor Toll-Like 4/efectos de los fármacos , Proteínas Wnt/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacos , Adolescente , Androstadienos/farmacología , Técnicas de Cultivo de Célula , Células Cultivadas , Cromonas/farmacología , Compuestos de Diazonio/farmacología , Relación Dosis-Respuesta a Droga , Escherichia coli , Humanos , Proteínas I-kappa B/antagonistas & inhibidores , Morfolinas/farmacología , Micotoxinas/farmacología , Inhibidor NF-kappaB alfa , FN-kappa B/antagonistas & inhibidores , Nitrilos/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Pirrolidinas/farmacología , Transducción de Señal/efectos de los fármacos , Sulfonas/farmacología , Tiocarbamatos/farmacología , Factores de Tiempo , Proteína Wnt-5a , Wortmanina , Adulto JovenRESUMEN
OBJECTIVES: The aim of the present study was to investigate the effects of lipopolysaccharide (LPS) on the migration and adhesion of human dental pulp stem cells (hDPSCs) and the associated intracellular signalling pathways. METHODS: hDPSCs obtained from impacted third molars were exposed to LPS and in vitro cell adhesion and migration were evaluated. The effects of LPS on gene expression of adhesion molecules and chemotactic factors were investigated using quantitative real-time reverse-transcriptase polymerase chain (qRT-PCR). The potential involvement of nuclear factor NF-kappa-B (NF-κB) or mitogen-activated protein kinase (MAPK) signalling pathways in the migration and adhesion of hDPSCs induced by LPS was assessed using a transwell cell migration assay and qRT-PCR. RESULTS: LPS promoted the adhesion of hDPSCs at 1µg/mL and 10µg/mL concentrations, 1µg/mL LPS showing the greater effect. Transwell cell migration assay demonstrated that LPS increased migration of hDPSCs at 1µg/mL concentration while decreasing it significantly at 10µg/mL. The mRNA expressions of adhesion molecules and chemotactic factors were enhanced significantly after stimulation with 1µg/mL LPS. Specific inhibitors for NF-κB and extracellular signal regulated kinases (ERK), c-Jun N-terminal kinase (JNK), and P38, markedly antagonised LPS-induced adhesion and migration of hDPSCs and also significantly abrogated LPS-induced up-regulation of adhesion molecules and chemotactic factors. In addition, specific inhibitors of SDF-1/CXCR4, AMD3100 significantly diminished LPS-induced migration of hDPSCs. CONCLUSIONS: LPS at specific concentrations can promote cell adhesion and migration in hDPSCs via the NF-κB and MAPK pathways by up-regulating the expression of adhesion molecules and chemotactic factors. CLINICAL SIGNIFICANCE: LPS may influence pulp healing through enhancing the adhesion and migration of human dental pulp stem cells when it enters into pulp during pulp exposure or deep caries.
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Pulpa Dental/citología , Lipopolisacáridos/farmacología , Células Madre/efectos de los fármacos , Adolescente , Adulto , Antracenos/farmacología , Bencilaminas , Butadienos/farmacología , Adhesión Celular/efectos de los fármacos , Moléculas de Adhesión Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Quimiocina CXCL12/antagonistas & inhibidores , Factores Quimiotácticos/análisis , Ciclamas , Escherichia coli , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Compuestos Heterocíclicos/farmacología , Humanos , Imidazoles/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , FN-kappa B/antagonistas & inhibidores , FN-kappa B/efectos de los fármacos , Nitrilos/farmacología , Piridinas/farmacología , Pirrolidinas/farmacología , Receptores CXCR4/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Tiocarbamatos/farmacología , Adulto Joven , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidoresRESUMEN
INTRODUCTION: Stem cells from the apical papilla (SCAPs) are important for tooth root development and may be candidates for regenerative endodontic procedures involving immature teeth. The potential use of SCAPs for clinical applications requires a better understanding of their responses to bacterial challenge. We have investigated the effects of exposure of these cells to lipopolysaccharide (LPS). Inflammatory responses arising from bacterial challenges can constrain postinjury tissue regeneration and the effects of nuclear factor I C (NFIC), which plays a critical role in tooth root development. NFIC has been explored for its anti-inflammatory action in the context of endodontic treatment of immature teeth where continued root development is an important outcome. METHODS: SCAPs were exposed to LPS, and the expression of Toll-like receptor-4 (TLR4), interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF-α) were assessed by real-time polymerase chain reaction (RT-PCR). The pLenti6.3/v5-NFIC plasmid encoding the full-length NFIC or NFIC silencing by si-RNA (small interfering RNA) in SCAPs were measured by Western blotting or RT-PCR; the effects of NFIC on IL-6, IL-8, and TNF-α were analyzed by RT-PCR. The protein levels were subsequently measured by enzyme-linked immunoassay. RESULTS: LPS induced the synthesis of IL-6, IL-8, and TNF-α in SCAPs in a time-dependent manner. Pretreatment with a TLR4 inhibitor significantly inhibited LPS-induced IL-6, IL-8, and TNF-α expression. Knockdown of NFIC increased the expression of IL-6, IL-8, and TNF-α, whereas the overexpression of NFIC resulted in the suppression of the inflammatory response stimulated by 1 µg/mL LPS, especially for IL-8. Together, these data show that LPS is recognized by the transmembranous receptor TLR4 to mediate inflammatory responses in SCAPs and NFIC overexpression can suppress LPS-initiated innate immune responses. CONCLUSIONS: The anti-inflammatory effects of NFIC overexpression provide a valuable target to dampen inflammatory responses in the infected pulp to allow tissue regeneration to occur.
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Antiinflamatorios/farmacología , Papila Dental/citología , Lipopolisacáridos/farmacología , Factores de Transcripción NFI/farmacología , Células Madre/efectos de los fármacos , Adipogénesis/fisiología , Adolescente , Técnicas de Cultivo de Célula , Diferenciación Celular/fisiología , Células Cultivadas , Papila Dental/inmunología , Técnicas de Silenciamiento del Gen , Silenciador del Gen , Humanos , Interleucina-6/análisis , Interleucina-8/análisis , Interleucina-8/efectos de los fármacos , Lipopolisacáridos/inmunología , Factores de Transcripción NFI/genética , Odontogénesis/fisiología , Osteogénesis/fisiología , ARN Interferente Pequeño , Receptor Toll-Like 4/análisis , Receptor Toll-Like 4/efectos de los fármacos , Ápice del Diente/citología , Factor de Necrosis Tumoral alfa/análisis , Factor de Necrosis Tumoral alfa/efectos de los fármacosRESUMEN
OBJECTIVE: To investigate the effects of ectomesenchymal stem cells on hematopoiesis after total body irradiation in rats. METHODS: The primary ectomesenchymal stem cells were isolated from E11.5 SD fetal mandibular processes by 2.5 g/L trypsin and cultured with DMEM/F12. The morphology and growth rate were observed by inverted microscope. Eighty SD male rats randomly divided into ectomesenchymal stem cells group (n = 20), fibroblast group (n = 20), saline group (n = 20) and control group (n = 20), the first three groups were irradiated with 60Co gamma rays at 6. 0 Gy. The number of their bone marrow nucleated cells was counted after 4 weeks; the forming ability of colony-forming unit-granulocyte macrophage (CFU-GM) and histopathology of bone marrow were also observed. RESULTS: The cultured cells displayed monolayer growth and fibroblast-like with 2-4 processes. The ectomesenchymal stem cells could increase the number of bone marrow nucleated cells and peripheral blood white cell count, and improve the forming ability of CFU-GM. After 4 weeks of transplantation, the number of the peripheral blood white cells in group A was more than that in groups B and C (P < 0.05), the contents of Hb in groups A and D was significantly higher than those in groups B and C (P < 0.05). After 4 weeks, the bone marrow nucleated cells in group A were significant more than those in groups B and C (P < 0.01); CFU-GM in groups A and D was higher than that in groups B and C (P < 0.01). CONCLUSION: Ectomesenchymal stem cells have characteristics of stem cells. It may improve hematopoiesis recovery of irradiated rats.
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Células Madre Hematopoyéticas/efectos de la radiación , Trasplante de Células Madre Mesenquimatosas , Animales , Médula Ósea , Recuento de Células , Ectodermo/citología , Rayos gamma , Células Progenitoras de Granulocitos y Macrófagos , Masculino , Células Madre Mesenquimatosas , Ratas , Ratas Sprague-Dawley , Irradiación Corporal TotalRESUMEN
BACKGROUND INFORMATION: Substantial evidence indicates the existence of NCSCs (neural crest-derived stem cells) in embryonic mandibular processes; however, they have not been fully investigated or isolated. The aim of the present study was to isolate stem cells from mandibular process during embryonic development by MACS (magnetic-activated cell sorting). The findings show that the cells are multipotent and self-renewing. RESULTS: LNGFR (low-affinity nerve-growth-factor receptor)+ cells were isolated from rat embryonic mandibular processes by MACS. The cells were grown in clonal culture by limiting dilution to assess their developmental potential. Clone analysis indicated that, first, LNGFR+ cells are multipotent, being able to generate at least neurons and Schwann cells, similar to peripheral neural crest stem cells. Secondly, multipotent LNGFR+ cells generate multipotent progenies, indicating that they are capable of self-renewal and therefore are stem cells. Thirdly, manipulation of the medium supplementation alters the fate of the isolated LNGFR+ cells. CONCLUSIONS: These results indicate that LNGFR antibodies label NCSCs with high specificity and purity, and suggest that positive selection using these antibodies may become the method of choice for obtaining multipotent cells from rat embryonic mandibular processes for tissue engineering or regenerative therapeutic use.