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1.
Mater Sci Eng C Mater Biol Appl ; 120: 111797, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33545919

RESUMO

Adequate and timely vascularization is crucial for the success of dental pulp tissue engineering. Hypoxia, an important driving force of angiogenesis, plays an important role in this process. However, few studies have investigated the fabrication of hypoxia-simulating biomaterials for dental applications. In this study, a novel hypoxia-mimicking, multi-walled carbon nanotubes/cobalt (MWCNTs/Co) nanocomposite was prepared using the metal-organic framework (MOF) route for the in situ insertion of MWCNTs into Co3O4 polyhedra. The obtained nanocomposites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Cobalt ion release of MWCNTs/Co was analyzed in vitro. Cell viability and proliferation were assessed by culturing stem cells from apical papilla (SCAP) with MWCNTs/Co nanocomposites. The angiogenic capacity of SCAP after exposure to nanocomposites was evaluated by enzyme-linked immunosorbent assay (ELISA), western blotting and the Matrigel angiogenesis assay. Our results proved that the synthesized MWCNTs/Co nanocomposites possessed a well-designed connecting structure and could release cobalt ions in a sustained way. The MWCNTs/Co nanocomposites at 50 µg/mL significantly upregulated hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) protein expression in SCAP, with no apparent cellular cytotoxicity. The conditioned medium collected from SCAP treated with MWCNTs/Co markedly promoted endothelial cells vessel formation. In conclusion, hypoxia-mimicking MWCNTs/Co nanocomposites exhibit promising angiogenic potential for dental tissue engineering and might provide an alternative solution for translational applications.

2.
BMC Womens Health ; 21(1): 39, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33509177

RESUMO

BACKGROUND: There is a noticeable lack of systematic researches on evaluating the correlation between serum estrogen levels and changes in brain functional areas of perimenopausal women.The aim of this study is to investigate the regional spontaneous brain activity changes in perimenopausal women. METHODS: Based on the resting-state functional magnetic resonance imaging datasets acquired from 25 perimenopausal women and 20 healthy women of reproductive age, a two-sample t-test was performed on individual normalized regional homogeneity (ReHo) maps. Relationships between abnormal ReHo values and the self-rating anxiety scale (SAS), the self-rating depression scale (SDS) were investigated with Pearson correlation analysis. We also investigated the correlation between abnormal ReHo values and serum estrogen level. RESULTS: In the perimenopausal group, we found increased ReHo in the right posterior cerebellum (region 2), left middle frontal gyrus and left middle cingulate gyrus ([Formula: see text]). Additionally, the ReHo values in left middle frontal gyrus and leftt middle cingulate gyrus showed positively significant correlation with the SAS, SDS scores. On the contrary, there was no significant correlation between the ReHo value in right posterior cerebellum and SDS, SAS scores. In the perimenopausal group, the ReHo values in the left middle frontal gyrus and left middle cingulate gyrus were negatively correlated with the serum estrogen level ([Formula: see text]). CONCLUSION: The results of this preliminary study have suggested that abnormal spontaneous activities of multiple brain regions during resting state was already altered in perimenopausal women. Alterative activities might be related to emotional regulation deficits and cognitive impairment, and might potentially represent the neural mechanism underlying perimenopausal period.

3.
BMC Musculoskelet Disord ; 21(1): 774, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33234145

RESUMO

BACKGROUND: In the management of early inflammatory joint of ankylosing spondylitis (AS), there is a need for reliable noninvasive quantitative monitoring biomarker to closely assess status of synovitis progression. Cognizant to this,studies geared on improving techniques for quantitative evaluation of micro-environment permeability of the joint space are necessary. Such improved techniques may provide tissue perfusion as important biological parameters and can further help in understanding the origin of early changes associated with AS. The purpose of this study was to prospectively evaluate the diagnostic performance and determine longitudinal relationships of early micro-environment active in the joint space of the sacroiliac joint (SIJ) with a rat model by using quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). METHODS: Thirty wistar male rats were randomly assigned to the model (n = 15) or control (n = 15) group. All rats underwent DCE-MRI of SIJ region at fixed time points (12, 17 and 22 weeks),between September 2018 and October 2019. Differences in permeability parameters between the two groups at the same time point were compared by using an independent samples t test. Spearman correlations of DCE-MRI parameters with different time points in model group were analyzed. All statistical analyses were performed with software. RESULTS: At 12 weeks,the Ktrans,Kep and Ve values in the model group were slightly lower than those in control group,but all the differences were not statistically significant (p > 0.05). Compared with control group,the transfer constant (Ktrans) values increased significantly at 17 weeks and 22 weeks in model group,while the rate constant (Kep) and volume of extravascular extracellular space (Ve) significantly increased only at 22 weeks(p < 0.05). The Ktrans,Kep and Ve were positively correlated with increasing time points (r = 0.946, P<0.01 for Ktrans; r = 0.945, P<0.01 for Kep; and r = 0.832, P<0.01 for Ve). CONCLUSION: Quantitative DCE-MRI parameters are valuable for evaluating the early longitudinal relationship of micro-environment permeability changes in the joint space of SIJ.

4.
Nanotechnology ; 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33242845

RESUMO

Transition metal oxides with high theoretical capacities are widely investigated as potential anodes for alkali-metal ion batteries. However, the intrinsic conductivity deficiency and large volume changes during cycles result in poor cycling stability and low rate capabilities. Graphene has been widely used to support metal oxide for enhanced performance, but the cycling life is limited by the aggregation/collapse of active materials on graphene surface. Herein, we significantly improve the battery performance of graphene-metal oxide composite via pore engineering and surface protection. In this architecture, the mesoporous NiFe2O4 is designed for fast ion diffusion and volume accommodation, and the outer graphene protection can further enhance the electrical conductivity and prevent the aggregation during cycle. Thus, as-prepared G@p-NiFe2O4@G composite for lithium storage delivers high capacity (1244 mA h g-1 after 300 cycles at 0.2 A g-1), excellent rate performance (563 mA h g-1 at 4 A g-1), and outstanding cycling life up to 1200 cycles at 1.5 A g-1. For sodium storage, it also displays good cycling stability and superior rate performance. Moreover, the effects of various microstructures on the battery performance, the reaction kinetics of various electrodes, and the reaction mechanism of NiFe2O4 have been systematically investigated in this work.

5.
ACS Omega ; 5(33): 20755-20764, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32875209

RESUMO

The addition of lactoferrin and three unsaturated fatty acids, oleic acid, docosahexaenoic acid (DHA), and linolenic acid, to dairy products was approved in recent years. Research into the biological activities of lactoferrin and these three unsaturated fatty acids has revealed anti-inflammatory, antiviral, antioxidant, antitumor, antiparasitic, and antibiotic effects. However, investigations and comparisons of lactoferrin + oleic acid/DHA/linolenic acid combinations in an esophageal cancer cell model and in xenograft tumor models have not been extensively reported, and the related mechanism of these combinations remains elusive. In the present study, the effects of lactoferrin and the three fatty acids on KYSE450 cell viability, migration, and invasion were investigated to choose the proper doses and effective combination in vitro. A tumor-bearing nude mouse model was established to investigate the role of selected combinations in inhibiting esophageal tumor formation in vivo. Metabonomics detection and data analysis were performed to screen special metabolites and related pathways, which were validated by western blotting. The results demonstrated that lactoferrin, the three unsaturated fatty acids, and their combinations inhibited the viability, migration, and invasion of KYSE450 cells and induced apoptosis and the lactoferrin + linolenic acid combination exhibited the strongest activity in suppressing KYSE450 tumor formation in vivo. The lactoferrin + linolenic acid combination inhibited phosphorylation in the JAK2/STAT3-related pathway by downregulating the special metabolite lithocholyltaurine, thereby suppressing formation of KYSE450 tumors.

6.
Ann Vasc Surg ; 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32891743

RESUMO

BACKGROUND: To explore the impact of thoracic endovascular aortic repair (TEVAR) on aortic remodeling (AR) and the relationship between AR and complications after TEVAR. METHODS: A total of 56 patients (2 type IIIA aortic dissection [AD] and 54 type IIIB AD) with complicated acute type B aortic dissection suitable for TEVAR were prospectively enrolled. There were 44 men (78%) and 12 women (22%) with an average age of 54 ± 13.8 years. Aortic enhanced computed tomography (CT) was performed pre-TEVAR and 3, 6, and 12 months postoperatively. The morphological changes in AR, namely aortic volume and false lumen thrombosis, were obtained by analyzing the CT data. The effect of TEVAR on AR was determined by the morphological changes in the aorta. The relationship between AR index, false lumen thrombosis, and complications was analyzed. RESULTS: The volume of the thoracic aortic true lumen gradually increased post-TEVAR, whereas the volume of the thoracic aortic false lumen gradually decreased. The volume of abdominal aortic total lumen and false lumen increased 6 months postoperatively. The AR index increased significantly 3 months postoperatively, which was negatively correlated with complications and mortality. The thoracic and abdominal aortic false lumen thrombosis developed gradually after TEVAR, and the degree of thoracic aortic false lumen thrombosis was negatively correlated with complications and mortality. CONCLUSIONS: TEVAR promotes AR. AR index and the degree of thoracic aortic false lumen thrombosis can serve as predictors of complications and mortality.

7.
Front Oncol ; 10: 1094, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733803

RESUMO

Esophageal cancer is a type of gastrointestinal carcinoma and is among the 10 most common causes of cancer death worldwide. However, the specific mechanism and the biomarkers in the proliferation and metastasis of esophageal tumors are still unclear. Therefore, the development of several natural products which could inhibit esophageal tumors deserve attention. In the present study, different sources of cancer cells were used to select the sensitive cell line (esophageal cancer cell KYSE450) and the proper dose of angustoline, which were utilized in the following cell viability, migration and invasion assays. Then the lipidomic detection of clinical samples (tissue and blood plasma) from esophageal cancer patients was performed, to screen out the specific phospholipid metabolites [PC (16:0/18:1) and LPC (16:0)]. Considering lysophosphatidylcholine acyltransferase 2 (LPCAT2) was tightly relative with phospholipids conversion, serine/threonine-protein kinase 11 (LKB1), 5'-monophosphate (AMP)-activated protein kinase (AMPK) and embryonic lethal, and abnormal vision, drosophila-like 1 (ELAVL1) were investigated, to evaluate their expression levels in esophageal tumor tissue and KYSE450 cells. Additionally, KYSE450 tumor bearing mouse model was constructed, the role of angustoline in inhibiting esophageal tumors through regulating LKB1/AMPK/ELAVL1/LPCAT2 pathway was validated, and found that the conversion from LPC (16:0) to PC (16:0/18:1) was blocked by angustoline in some degree. The above results for the first time proved that angustoline suppressed esophageal tumors through activating LKB1/AMPK and inhibiting ELAVL1/LPCAT2, which consequently blocked phospholipid remodeling from LPC (16:0) to PC (16:0/18:1).

8.
J Prosthet Dent ; 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32829886

RESUMO

STATEMENT OF PROBLEM: Additive manufacturing or 3D printing is gaining popularity in dentistry, including for interim fixed dental prostheses (IFDPs). However, evidence regarding the color stability of 3D-printed IFDPs is lacking. PURPOSE: The purpose of this in vitro study was to investigate whether different surface treatments could affect the color stability of milled and 3D-printed IFDPs after simulated physiological aging. MATERIAL AND METHODS: Forty milled IFDPs were fabricated with a 5-axis dental mill (DWX-51D; Roland DGA Corp) from polymethyl methacrylate disks (Temp Esthetic 98, A3.5, 98.5×16 mm; Harvest Dental Products, LLC). Forty 3D-printed IFDPs were fabricated with an in-office digital light processing 3D printer (MAX; Asiga) and light-polymerizing resin (NextDent Crown & Bridge A3.5; NextDent B.V). All milled and 3D-printed IFDPs were allocated into 4 different groups (n=10), according to different surface treatments: Control, Polish, Optiglaze, and Skinglaze. In the Control group, no surface treatment was applied to the IFDPs. For the Polish group, IFDPs were finished and polished with aluminum oxide finishers/polishers (Enhance PoGo Complete Kit; Dentsply Sirona). For the Optiglaze and Skinglaze groups, specimens were first finished and polished and prepared with additional light-polymerizing protective coatings (Optiglaze; GC America Inc, or New Outline Skin Glaze; anaxdent North America). Shade measurements were recorded with a digital spectrophotometer (Vita Easyshade V; VITA North America) before and after the thermocycling for the color stability comparisons. The effects of interim prosthesis type and surface treatments on ΔE∗, ΔL∗, Δa∗, and Δb∗ were examined using 2-way analysis of variance (ANOVA), and ΔE∗ was considered as the primary outcome variable. Post hoc pairwise comparisons were performed by using the Tukey honestly significant difference (HSD) method (α=.05 for all tests). RESULTS: Milled IFDPs had significantly smaller ΔE∗ than 3D-printed prostheses for the Control group only (P<.001). Within the milled IFDPs, Optiglaze group (mean ±standard deviation, 1.01 ±0.38) had significantly lower ΔE∗ than all the other surface treatments groups (Control group: 2.38 ±0.44, P<.001; Polish group: 1.83 ±0.51, P=.025; and Skinglaze group: 1.85 ±0.78, P=.021). Within the 3D-printed IFDPs, the Control group (3.83 ±0.71) had significantly larger ΔE∗ than all other surface treatments (Polish group: 2.66 ±0.89, P=.018; Skinglaze group: 1.40 ±0.73, P<.001; and Optiglaze group: 1.37 ±0.67, P<.001). The Polish group had significantly higher ΔE∗ than Skinglaze group (P=.009) and Optiglaze group (P=.007), while Skinglaze and Optiglaze groups were not significantly different from each other (P=1.000). CONCLUSIONS: For the milled IFDPs, only the nano-filled, light-polymerizing protective coating significantly lowered color changes after thermocycling simulating 6 months of intraoral physiological aging. For the 3D-printed IFDPs, surface polishing and both light-polymerizing protective coating agents all significantly reduced color changes of the prostheses after thermocycling. The protective effect of light-polymerizing coating agents was more substantial.

9.
BMC Musculoskelet Disord ; 21(1): 472, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32689978

RESUMO

BACKGROUND: Currently, few studies have described the relationship between functional MRI findings and histology of normal sacroiliac joint (SIJ). Besides, due to the difficulties in access to SIJ, authentic animal models are important in providing opportunities for quantitative parameter extraction on imaging. AIMS: This study aimed at exploring the parameters of Intravoxel Incoherent Motion Diffusion-Weighted Imaging (IVIM-DWI) and Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) and comparing them with the histology of the SIJ in normal rats with different ages. METHODS: A total of thirty 7-week-old male Wistar rats were included in the study. The parameters of IVIM-DWI and DCE-MRI in the bone marrow and the joint space of SIJ were measured at 8, 13, 18, 23, 28, and 33 weeks. The histological analysis of the SIJ was examined using light microscopy. One-way ANOVA was used for statistical analysis. RESULTS: The D values in the sacral and iliac bone marrow of normal rats decreased with an increase in age. One-way ANOVA analysis indicated a significant difference in D values in different age groups (P<0.005). The normal values of D*, f, Fenh (%), Senh (%/s) in the sacral bone marrow, the iliac bone marrow, and the joint space in SIJ of normal rats were obtained. The results showed that in the six groups of rats of different ages, the histology of the SIJ surface was smooth and clear, the cartilage cells were intact, and no thickening or pannus formation was observed. CONCLUSIONS: This study obtained the IVIM-DWI and DCE-MRI parameters of the sacral and iliac bone marrow and the synovial area of the joint space in normal rats. The parameters in normal rats can be used in future research to compare to similar parameters in animal models or patients with SIJ diseases. This study serves as a guide for future research in SIJ diseases.

10.
J Dairy Sci ; 103(6): 4895-4906, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32229112

RESUMO

The objective of this study was to evaluate the protection conferred by lactoferrin, α-lactalbumin, and ß-lactoglobulin in cerebral ischemia reperfusion (I/R) injury. Rat pheochromocytoma (PC12) cells were used to construct an oxygen and glucose deprivation model in vitro, and ICR mice underwent carotid artery "ligation-relaxation" to construct a cerebral I/R injury model in vivo. The levels of toll-like receptor 4 (TLR4) and downstream factors including nuclear factor-κB, tumor necrosis factor-α, and IL-1ß were measured. Metabonomics detection and data mining were conducted to identify the specific metabolic sponsor of the 3 proteins. The results showed that lactoferrin, α-lactalbumin, and ß-lactoglobulin protected neurons from cerebral I/R injury by increasing the level of bopindolol and subsequently inhibiting the TLR4-related pathway to different degrees; ß-lactoglobulin had the strongest activity of the 3 proteins. In summary, this study is the first to investigate and compare the protective effects of lactoferrin, α-lactalbumin, and ß-lactoglobulin in a cerebral stroke model. The results implicate TLR4 as a novel target of the 3 bioactive proteins to prevent cerebral I/R injury.


Assuntos
Lactalbumina/uso terapêutico , Lactoferrina/uso terapêutico , Lactoglobulinas/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Animais , Glucose/metabolismo , Interleucina-1beta/metabolismo , Lactalbumina/metabolismo , Lactoferrina/metabolismo , Lactoglobulinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , NF-kappa B/metabolismo , Oxigênio/metabolismo , Células PC12 , Ratos , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
ACS Nano ; 14(4): 4463-4474, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32250588

RESUMO

The microstructure of large-capacity anodes is of great importance in determining the performance of sodium- and potassium-ion batteries. Yolk-shell nanostructures promise excellent structural stability but suffer from insufficient charge transfer rate during cycles. Herein, we tackle this challenge by constructing a single-walled carbon nanotube (SWNT) internally bridged yolk-shell structure, inside which SWNTs cover the surface of the yolk and connect the yolk and shell, for better electron/ion transportation. Combining the merits of both yolk-shell structure and conductive SWNT channels, the as-prepared Fe1-xS/SWNT@C composite manifests high reversible capacity and ultralong cycling stability up to 8700 cycles. Moreover, it displays the best rate capability (317 mA h g-1 at 20 A g-1 for Na+ and 236 mA h g-1 at 10 A g-1 for K+) among the reported yolk-shell structures and iron-sulfide-based anodes thus far. The kinetic analysis and density functional theory calculations further reveal that the Fe1-xS/SWNT heterointerface can effectively enhance the reversibility of K+ storage and decrease the K+ diffusion energy barrier, leading to excellent pseudocapacitive behavior and fast ion transportation for outstanding rate capability.

12.
Food Chem ; 319: 126368, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32155537

RESUMO

Maillard reaction products (MRPs), produced in the heating of food, might pose adverse effects on human health. As a classical MRP, the toxicity of furosine in kidney tissue was evaluated and the related mechanism was investigated here. We detected the concentration of furosine in mouse serum and organs using ultra-high-performance liquid chromatography, and screened out phosphatidylethanolamine (PE; 18:0/16:1) as the special metabolite in kidney by metabonomics analysis. Furthermore, furosine was verified to induce ferroptosis in kidney cells by quantitative real-time RT-PCR (q-PCR) and western blotting. The affinity between furosine and aldose reductase (AR) was measured by surface plasmon resonance (SPR), indicating AR is one of the targets of furosine. In addition, the furan ring was shown to be the main active group via structure-activity relationship (SAR) studies of furosine and other MRPs, which were toxic to kidney cells by activating ferroptosis pathway.


Assuntos
Furanos/química , Produtos Finais de Glicação Avançada/metabolismo , Rim/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Feminino , Ferroptose , Produtos Finais de Glicação Avançada/química , Rim/lesões , Lisina/análogos & derivados , Lisina/metabolismo , Reação de Maillard , Camundongos , Camundongos Endogâmicos ICR
13.
Magn Reson Imaging ; 68: 30-35, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31978516

RESUMO

OBJECTIVE: To prospectively evaluate the ability of IVIM-DWI and DCE-MRI in detecting early activity of sacroiliitis in rat model of ankylosing spondylitis by comparing with pathological results. METHODS: 20 wistar male rats were induced by bovine proteoglycan combined with complete/incomplete Freund's adjuvant as model group, and 20 healthy male rats were used as the control group. The parameters of IVIM-DWI and DCE-MRI in synovial regions of SIJ were measured respectively at 7th, 12th, 17th, and 22th weeks after the last induction, and the pathological features of SIJ were taken also, further studying the pathological characteristics of sacroiliac region. Independent sample t-test and one-way ANOVA were used for statistical analysis. The prediction parameters and diagnostic efficiency were compared by ROC curve. RESULTS: There was no significant difference of image parameters between the model and control groups at the 7th, 12th weeks after the last induction, and there were no positive findings in histopathological examination at the same time. At the 17th week after induction, the f and Fenh%, Senh% between the model and the control groups were statistically significant. At the 22th week, there was a statistically significant increase all the values in model group than those in control group (P < 0.05). Histologic examination confirmed inflmmtorycell infiitrtion at the 17th week and pannus forming of synovium on the surface of cartilage at the 22th week in the model groups. The Fenh%, Senh%, Dslow and f had the moderate diagnostic efficiency and the areas under the curve were 0.77, 0.75, 0.77 and 0.82 respectively. The Senh% demonstrated the highest sensitivity (71.4%) and f demonstrated the highest specificity (95.0%). CONCLUSION: IVIM-DWI and DCE-MRI can be used as the sensitive imaging methods to detect and accurate diagnosis the early activity of sacroiliitis in AS.


Assuntos
Meios de Contraste , Processamento de Imagem Assistida por Computador/métodos , Sacroileíte/diagnóstico por imagem , Espondilite Anquilosante/diagnóstico por imagem , Análise de Variância , Animais , Área Sob a Curva , Bovinos , Imagem de Difusão por Ressonância Magnética , Modelos Animais de Doenças , Masculino , Movimento (Física) , Variações Dependentes do Observador , Proteoglicanas/química , Curva ROC , Ratos , Ratos Wistar , Sensibilidade e Especificidade
14.
Nanotechnology ; 30(46): 465402, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31426037

RESUMO

In this work, we report a high-performance anode material created by rationally encapsulating multi-walled carbon nanotubes (MWNTs) within hollow Fe3O4 nanotubes followed by applying a carbon coating. When tested for lithium storage, as-prepared MWNT@hollow Fe3O4@C coaxial nanotubes present high specific capacity, superior rate performance, and outstanding cycling stability. It is capable of delivering high capacities of 758 mA h g-1 at 500th cycle at 0.2 A g-1, and 409 mA h g-1 after 1000 cycles at a high rate of 1.5 A g-1. This excellent performance can be attributed to its unique architecture, which provides high electrical conductivity, offers enough void space for volume accommodation, and mitigates the pulverization of Fe3O4 during cycles.

15.
Stem Cells Int ; 2019: 8749090, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30728842

RESUMO

This study is aimed at investigating the effect of amifostine (AMI) on rat bone marrow stromal stem cells (BMSCs) exposed to 2 Gy radiation. The BMSCs were divided into four groups, namely, group A that received 0 Gy radiation, group B that received 0 Gy radiation and AMI, group C that received 2 Gy radiation, and group D that received 2 Gy radiation and AMI. The proliferation, apoptosis, and distribution of BMSCs in the cell cycle, along with their osteogenesis ability, adipogenesis ability, and ROS production, were subsequently examined. The levels of ALP, PPARγ, P53, and TNFα were determined by Western blotting. The results demonstrated that the proliferation of BMSCs and the levels of ALP in group C were much lower than those in group A. The production of ROS and levels of PPARγ, P53, and TNFα in the group that received 2 Gy radiation were much higher than those in group A. Furthermore, the production of ROS and the levels of PPARγ, P53, and TNFα were much lower in group D than in group C. Additionally, the levels of ALP and extent of cell proliferation were much higher in group D than in group C. The results demonstrated the potential of AMI in reducing the side effects of radiation in BMSCs and in treatment of bone diseases caused by radiation.

16.
Int J Oral Maxillofac Implants ; 34(1): 91-98, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30695087

RESUMO

PURPOSE: The possibility that the sympathetic nervous system (SNS) controls bone remodeling has been raised; however, the actual function of the SNS in osseointegration is still unknown. This study aimed to investigate the effect of chemical sympathectomy on peri-implant osseointegration in adult mice. MATERIALS AND METHODS: Forty C57BL/6J mice (8-week-old) were divided into two groups: a sympathectomy group and a control group, which were administered 6-hydroxydopamine and saline, respectively, by intraperitoneal injection for 5 days. Then, the mice were exposed to implant surgery. Analyses of serum chemistry, microcomputed tomography, biomechanical test, and bone histomorphometry were employed at 2 and 4 weeks. RESULTS: Compared with the control, the chemical sympathectomy group had a higher serum level of C-terminal collagen I cross-links but lower serum osteocalcin. After 4 weeks, peri-implant trabecular microstructure, including trabecular volume, trabecular thickness, the percentage of osseointegration, and bone-to-implant contact, was lower; however, the trabecular separation was higher in the sympathectomy group mice in comparison with the control group. In addition, the strength of bone-titanium integration measured by the biomechanical resistance test was lower. Furthermore, histomorphologic evidence revealed that the osteoclast counts were higher in the sympathectomy group, while the mineral apposition rate and the bone formation rate per bone surface were significantly lower. CONCLUSION: Within the limitations of this experimental study, the data showed that chemical sympathectomy has a negative effect in peri-implant osseointegration, suggesting that the SNS may need to be taken into consideration in terms of peri-implant bone healing.


Assuntos
Remodelação Óssea/fisiologia , Prótese Ancorada no Osso , Osseointegração/fisiologia , Simpatectomia Química/efeitos adversos , Sistema Nervoso Simpático/fisiologia , Animais , Colágeno Tipo I/sangue , Implantes Dentários , Camundongos , Camundongos Endogâmicos C57BL , Osteocalcina/sangue , Osteoclastos , Osteogênese/fisiologia , Titânio/química , Microtomografia por Raio-X
17.
J Cell Biochem ; 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30387222

RESUMO

The ß2-adrenergic receptor (ß2-AR) signaling on bone cells is the major contributor in the effect of the sympathetic nervous system on bone turnover. However, it remains unclear whether receptor activator of nuclear factor κ-Β ligand (RANKL) modulation and neuropeptides expression in osteocytes are responsible for the mechanism. This study used ß2-AR stimulation to investigate cell cycle and proliferation, the gene and protein expression of RANKL, and osteoprotegerin (OPG), as well as neuropeptides regulation in osteocytic MLO-Y4 cells. Clenbuterol (CLE; a ß2-AR agonist) slightly promoted the growth of MLO-Y4 cells in a concentration-dependent effect but had no effect on the proliferation index. And the concentration of 10-8 M showed a significant increase in the S-phase fraction on day 3 in comparison with the control. Additionally, CLE-promoted osteoclast formation and bone resorption in osteocytic MLO-Y4 cell-RAW264.7 cell cocultures. RANKL expression level and the ratio of RANKL to OPG in MLO-Y4 cells were enhanced in CLE treatment but were rescued by blocking ß2-AR signaling. However, neuropeptide Y and α-calcitonin gene-related peptide, two neurogenic markers, were inhibited in CLE treatment of MLO-Y4 cells, which was reversed by a ß2-AR blocker. The results indicate that osteocytic ß2-AR plays an important role in the regulation of RANKL/OPG and neuropeptides expression, and ß2-AR signaling in osteocytes can be used as a new valuable target for osteoclast-related pathologic disease.

18.
Br J Haematol ; 182(4): 554-558, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29962035

RESUMO

Allogeneic haematopoietic stem cell transplantation (HSCT) is the only available curative therapy for patients with thalassaemia major. With the progress in human leucocyte antigen (HLA) antigen typing technology and supportive care, the outcomes of thalassaemia major have greatly improved in recent years, even in high-risk patients. However, the problem of finding a suitable donor is still a major obstacle to curing these patients. In recent decades, the lack of available HSCT donors has led to the increased use of haploidentical donors (HDs) for HSCT in haematological malignancies. Recently, we explored the effect of HD HSCT to eight children with thalassaemia major based on the FBCA conditioning regimen (fludarabine, busulphan, cyclophosphamide, antithymocyte globulin), which is usually used in leukaemia patients receiving haploidentical HSCT in our centre. So far, all of the transplanted patients have a stable engraftment and are transfusion independent in daily life. This encouraging result has revised our previous conception about haploidentical HCST for thalassaemia major and strongly suggests that HD HSCT is a feasible and safe method for thalassaemia major patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Sobrevivência de Enxerto , Transplante de Células-Tronco Hematopoéticas , Condicionamento Pré-Transplante , Talassemia beta/terapia , Adulto , Aloenxertos , Soro Antilinfocitário/administração & dosagem , Bussulfano/administração & dosagem , Criança , Pré-Escolar , Ciclofosfamida/administração & dosagem , Feminino , Humanos , Masculino , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados
19.
Nanoscale ; 10(17): 7999-8008, 2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29666849

RESUMO

Sodium ion batteries (SIBs) have attracted ever-growing attention as promising candidates for large-scale energy storage applications, due to the abundant sodium resources and their low cost. Nevertheless, it is still a significant challenge to realize superior electrode materials with high capacity and good cyclability. To address these problems, herein, a rational microstructure of the SnS2-carbon composite has been designed for superior performance, which consists of MWNTs as a carbon matrix, the SnS2 nanosheet (NS) as an active material, the outer carbon coating as a protection layer, as well as the interior void space for volume accommodation. As an anode material for SIBs, the so-produced MWNT@SnS2 NS@C electrode delivered a high initial capacity of 910 mA h g-1 at 100 mA g-1 and a good retention of 78% after 100 cycles. The sodium storage mechanism of SnS2 was systematically studied through CV, ex situ XPS, and ex situ HRTEM characterization studies, disclosing the reversible conversion and alloying reactions of SnS2 during sodiation/desodiation processes. Moreover, ex situ TEM was further applied to clarify the relationships between the SnS2-C microstructure and sodium storage performance. Our result represents a significant step towards rational design electrodes with high capacity and cyclability for sodium ion batteries.

20.
Biomed Res Int ; 2018: 8139424, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30627574

RESUMO

Background: Clinical data demonstrated that failure rate of titanium implant in irradiated bone was 2-3 times higher than that in nonirradiated bone and it is difficult to get the ideal results in irradiated bone. Purpose: The aim of the study was to investigate the effects of HBO, BMP2, VEGF165, and combined use of BMP2/VEGF165 on osseointegration and stability of titanium implant in irradiated bone. Materials and Methods: Sixty rabbits were randomly assigned to 5 groups (control group, HBO group, VEGF165 group, BMP2 group, and BMP2/VEGF165 group) after receiving 15 Gy radiation. Implant surgery was performed on tibias eight weeks later. They were sacrificed at two or eight weeks after operation. Implant stability, calcium, and ALP activity in serum, the ratio of bone volume to total volume, the rate of bone growth, and gene expression were assessed. Result: There was no mortality and no implants failed during the experiment. Implant stability was significantly compromised in the control group compared to the other four experimental groups, and the BMP2/VEGF165 group had the highest implant stability. HBO, BMP2, and VEGF165 significantly increased BV/TV and the rate of bone growth, while the BMP2/VEGF165 showed the best effect among groups. The expression of RUNX2 in HBO, BMP2, and VEGF165/BMP2 group was higher than that in the VEGF165 and control groups at two weeks. The expression of OCN in HBO, BMP2, VEGF165, and VEGF165/BMP2 groups was higher than that in the control group, and the gene expression of CD31 was higher in HBO, VEGF165, and BMP2/VEGF165 groups than that in control and BMP2 groups. Conclusion: HBO, BMP2, and VEGF165 could increase bone formation around the implant and improved the implant stability in irradiated bone. The combination use of BMP2 and VEGF165 may be promising in the treatment of implant patients with radiotherapy.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Substitutos Ósseos , Prótese Ancorada no Osso , Raios gama , Osseointegração , Titânio , Fator A de Crescimento do Endotélio Vascular/farmacologia , Animais , Antígenos de Diferenciação/biossíntese , Masculino , Osseointegração/efeitos dos fármacos , Osseointegração/efeitos da radiação , Coelhos , Distribuição Aleatória
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