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1.
Acta Pharmaceutica Sinica B ; (6): 2269-2280, 2023.
Artigo em Inglês | WPRIM | ID: wpr-982843

RESUMO

Inflammation, abnormal cholesterol metabolism, and macrophage infiltration are involved in the destruction of the extracellular matrix of the nucleus pulposus (NP), culminating in intervertebral disc degeneration (IDD). Whether nimbolide (Nim), a natural extract, can alleviate IDD is unclear. In this study, we demonstrated that Nim promotes cholesterol efflux and inhibits the activation of the nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways by activating sirtuin 1 (SIRT1) in nucleus pulposus cells (NPCs) during inflammation. Thus, Nim balanced matrix anabolism and catabolism of NPCs. However, the inhibition of SIRT1 significantly attenuated the effects of Nim. We also found that Nim promoted the expression of SIRT1 in RAW 264.7, which enhanced the proportion of M2 macrophages by facilitating cholesterol homeostasis reprogramming and impeded M1-like macrophages polarization by blocking the activation of inflammatory signaling. Based on these results, Nim can improve the microenvironment and facilitate matrix metabolism equilibrium in NPCs. Furthermore, in vivo treatment with Nim delayed IDD progression by boosting SIRT1 expression, modulating macrophage polarization and preserving the extracellular matrix. In conclusion, Nim may represent a novel therapeutic strategy for treating IDD.

2.
Chinese Journal of Stomatology ; (12): 26-31, 2020.
Artigo em Chinês | WPRIM | ID: wpr-798686

RESUMO

Objective@#To evaluate the bond performance of primers, universal adhesives and self-adhesive resin cements containing methacryloyloxydecyl dihydrogen phosphate (MDP) to zirconia.@*Methods@#Two hundred and ten yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) plates were prepared and divided into seven groups according to each of six MDP-containing products and one MDP-free resin cement. Two primers, two universal adhesives and two self-adhesive resin cements were applied on the specimens after these specimens recived alumina air abrasion. The group of MDP-free resin cement was set as control. Each group contained 30 specimens. Y-TZP plates were bonded to resin composite to build resin bonding specimens, and half of these plates were stored in distilled water at 37 ℃ for 24 hours, the other half were stored for 12 months. Shear bond strength (SBS) test and fracture modes analysis were performed.@*Results@#The SBS values of all the experimental groups were above 9.51 MPa, which increased 24-hour values compared to the (5.04±0.50) MPa of the control group. Group using one of the self-adhesive resin cement yielded the highest SBS, (11.06±0.84) MPa. SBS of all groups decreased significantly compared to 24-hour SBS after aging (P<0.05), however, the SBS values of MDP-containing products groups can still be maintained above 7.44 MPa. Two self-adhesive cement groups and one of the universal adhesive group maintained higher SBS values, and the values were statistical different from those from the two primer groups (P<0.05) .@*Conclusions@#Different MDP-containing products have different effects on the bond durability of zirconia.

3.
The Journal of Advanced Prosthodontics ; : 286-296, 2019.
Artigo em Inglês | WPRIM | ID: wpr-761418

RESUMO

PURPOSE: The aim was to study the masking ability of high-translucency monolithic zirconia and provide guidance in selecting resin luting cements in order to mask discolored substrates. MATERIALS AND METHODS: 160 high-translucency zirconia specimens were divided into 32 groups depending on their thickness and shades. Using five shades of try-in paste, the specimens were luted onto the sub strates (Co-Cr, precious-metal, opaque porcelain-sintered Co-Cr, opaque porcelain-sintered precious-metal, and 5M3-shade zirconia). All CIELAB color parameters were measured and statistically analyzed. RESULTS: Zirconia shade and thickness and try-in paste shade affected CIELAB color parameters (P=.000) in different substrates groups, and there were interactions among these factors (P=.000). All five try-in paste shades can be chosen to achieve ΔE values of zirconia with 1.2 – 1.5 mm for masking dark-tooth-like 5M3-shade and zirconia with 1.5 mm for masking precious-metal groups < 2.6. Only suitable try-in paste shades were used, can ΔE values that less than 2.6 be achieved when applied translucent monolithic zirconia with 0.7–1.0 mm for masking dark-tooth-like 5M3-shade and zirconia with 0.7 – 1.2 mm for masking precious-metal groups. CONCLUSION: Choosing suitable resin cement shades is necessary for high-translucency monolithic zirconia to achieve ideal masking ability (ΔE < 2.6) on the dark-tooth.


Assuntos
Máscaras , Cimentos de Resina , Espectrofotometria
4.
The Journal of Advanced Prosthodontics ; : 313-323, 2019.
Artigo em Inglês | WPRIM | ID: wpr-786588

RESUMO

PURPOSE: Shear bond strength (SBS) test is the most commonly used method for evaluating resin bond strength of zirconia, but SBS results vary among different studies even when evaluating the same bonding strategy. The purpose of this study was to promote standardization of the SBS test in evaluating zirconia ceramic bonding and to investigate factors that may affect the SBS value of a zirconia/resin cement/composite resin bonding specimen.MATERIALS AND METHODS: The zirconia/resin cement/composite resin bonding specimens were used to simulate loading with a shear force by the three-dimensional finite element (3D FE) modeling, in which stress distribution under uniform/non-uniform load, and different resin cement thickness and different elastic modulus of resin composite were analyzed. In vitro SBS test was also performed to validate the results of 3D FE analysis.RESULTS: The loading flat width was an important affecting factor. 3D FE analysis also showed that differences in resin cement layer thickness and resin composite would lead to the variations of stress accumulation area. The SBS test result showed that the load for preparing a SBS specimen is negatively correlated with the resin cement thickness and positively correlated with SBS values.CONCLUSION: When preparing a SBS specimen for evaluating bond performance, the load flat width, the load applied during cementation, and the different composite resins used affect the SBS results and therefore should be standardized.


Assuntos
Cimentação , Cerâmica , Resinas Compostas , Módulo de Elasticidade , Técnicas In Vitro , Métodos , Cimentos de Resina
5.
West China Journal of Stomatology ; (6): 145-149, 2017.
Artigo em Chinês | WPRIM | ID: wpr-357505

RESUMO

<p><b>OBJECTIVE</b>To analyze chemical mechanism of bonding improvement of zirconia via 10-methacryloyloxydecyl dihydrogen phosphate (MDP) conditioning.</p><p><b>METHODS</b>Various models were created for tetragonal zirconia crystals, molecular MDP, and MDP complex, and tetragonal zirconia crystal. Thermodynamic methods were used to analyze configuration between MDP and tetragonal zirconia crystal through calculation of their Gibbs free energy values and equilibrium constants.</p><p><b>RESULTS</b>Two potential configurations (double- and single-coordinate) may occur between MDP and ZrO2 crystal clusters. Thermodynamic calculations showed that -147.761 and -158.073 kJ·mol⁻¹ Gibbs free energy were required to form single- and double-coordinate configurations; their negative signs indicate that reactions for both configurations can occur. Equilibrium constant for single-coordinate configuration was 7.72×10²⁵, which was less than that of double-coordinate configuration (4.95×10²⁷), suggesting that the latter was more stable.</p><p><b>CONCLUSIONS</b>MDP can spontaneously establish a double-coordinate configuration with zirconia.
.</p>


Assuntos
Teste de Materiais , Metacrilatos , Fosfatos , Zircônio
6.
Chinese Journal of Geriatrics ; (12): 990-992, 2016.
Artigo em Chinês | WPRIM | ID: wpr-502440

RESUMO

Objective To establish normal reference ranges for serum cystatin C (Cys C)in relatively healthy middle-aged and elderly(>50 years)Chinese individuals.Methods A total of 1087 candidates were consecutively selected and serum Cys-C levels were measured by transmission turbidimetry.Frequency analysis and histogram were used to establish the 95% confidence reference range according to methods provided by CLSI (C28-A2).Results Based on the definition and verification procedures for clinical laboratory reference ranges(CLSI C28-A2,second edition),Cys-C levels of 1087 participants fell within the range of 0.30-1.55 mg/L;Male participants had higher serum Cys-C levels than female participants(Z=-10.19,P<0.01).The serum Cys-C level increased with age,regardless of gender(R =0.600,P< 0.01).Differences in Cys-C levels between age groups were statistically significant (x2=411.17,P< 0.01).The reference ranges of normal serum Cys-C levels for different age groups (50-,55-,60-,65-,70-,75-,) were 0.42-0.98mg/L,0.45-1.04mg/L,0.47-1.34mg/L,0.46-1.38mg/L,0.61-1.33mg/L,0.61-1.28 mg/L,respectively,for males,and 0.39-0.94mg/L,0.42-1.01mg/L,0.40-0.91mg/L,0.46-1.03mg/L,0.57-1.04mg/L,0.55-1.27mg/L,respectively,for females.Conclusions This study established preliminary normal serum Cys-C reference ranges for healthy middle-aged and elderly(> 50 years)individuals in this region,which can serve as parameters for disease diagnosis and treatment evaluation.

7.
Journal of Practical Stomatology ; (6): 743-747, 2015.
Artigo em Chinês | WPRIM | ID: wpr-479832

RESUMO

Objective:To evaluate the toxicity of NaHCO3 coagulated silica gel for coating on the zirconia bonding surface in vivo. Methods:The silica gel was subjected to short term systemic toxicity test by delayed-type hypersensitivity test by oral route and oral mucosa irritation test according to the YY/T 0244-1 996 standards,T1 6886.1 0-2005 /ISO 1 0993-1 0:2002 standards and YY/T 01 27. 1 3-2009 standards respectively.Results:In the short term systemic acute toxicity tested mice there was no significant difference in the weekly food utilization rate and relative body weight growth rate between the experimental and control groups.No abnormality and path-ological change were observed.The delayed-type hypersensitivity test showed that no erythema and edema reaction presented in all the test cavies after 24 and 48 h of stimulation contact,and the sensitization rate was 0.There was no local or systemic pathological change in all the oral mucosa irritation test animals.Conclusion:NaHCO3 procoagulant silica gel has no in vivo toxicity.

8.
Chongqing Medicine ; (36): 5101-5102,5106, 2015.
Artigo em Chinês | WPRIM | ID: wpr-603094

RESUMO

Objective To discuss the clinical efficacy between the small skull-window microsurgical surgery and conventional trauma craniotomy in the treatment of hypertensive cerebral hemorrhage .Methods The clinical data of patients with hypertensive cerebral hemorrhage treated with two different approaches from January 2010 to October 2014 were analyzed retrospectively .Re-sults The re-hemorrhage rate of patients treated with conventional trauma craniotomy was relatively low ,compared with patients treated with small skull-window microsurgical surgery .small skull-window microsurgical surgery was superior than conventional trauma craniotomy in the incidence of postoperative complications ,disability rate and patients′ hospitalization time(P< 0 .05) .Con-clusion Small skull-window microsurgical surgery is superior than conventional trauma craniotomy .

9.
Chongqing Medicine ; (36): 1510-1511, 2015.
Artigo em Chinês | WPRIM | ID: wpr-464975

RESUMO

Objective To investigate the correlation between insulin resistance with female overactive bladder (OAB) .Meth‐ods 96 female patients with OAB were selected as the observation group and contemporaneous 92 women with healthy physical ex‐amination were taken as the control group .The fasting plasma glucose (FPG) ,triglycerides (TG) ,total cholesterol (TC) ,high‐den‐sity lipoprotein (HDL‐C) ,low‐density lipoprotein (LDL‐C) ,fasting insulin (FINS) ,and C reaction protein (CRP) levels were measured in the two groups .The insulin resistance index was calculated by the homeostasis model assessment of insulin resistance (HOMA‐IR) .Results The waist circumference ,body mass ,body mass index (BMI) ,hypertension cases and proportion of meno‐pause cases in the observation group were higher than those in the control group .FPG ,TG ,FINS ,CRP levels and HOMA‐IR in the observation group were significantly higher than those in the control group ,while the HDL‐C level was lower than that in the con‐trol group .In addition ,the differences in TC and LDL‐C levels between the two groups were not statistically significant (P>0 .05) . Conclusion Insulin resistance has no correlation with female OAB .

10.
West China Journal of Stomatology ; (6): 500-503, 2013.
Artigo em Chinês | WPRIM | ID: wpr-315924

RESUMO

<p><b>OBJECTIVE</b>To evaluate the effects of a zirconia primer and a self-adhesive resin cement on the resin bonding zirconia.</p><p><b>METHODS</b>Eighty zirconia blocks were manufactured, alumina-sandblasted, and randomly divided into five groups that received surface-treatments using different resin cements: group C, treated with a conventional bisphenol-A diglycidyl dimethacrylate (Bis-GMA)-based resin cement; group R, treated with a self-adhesive resin cement; group S, silica-coated via a Sol-gel process, conditioned with silane, and then treated with the Bis-GMA-based resin cement; group ZC, conditioned with a zirconia primer (Z-Prime Plus) and subsequently treated with the Bis-GMA-based resin cement; group ZR, conditioned with the zirconia primer and treated with the self-adhesive resin cement. Light-cured composite resin cylinders were prepared and bonded on the prepared zirconia blocks. Half of the specimens in each group were water-stored for 24 hours, whereas the remaining specimens were aged by thermocycling. All specimens were then subjected to shear bond strength (SBS) testing. Fourier transmission infrared (FT-IR) spectroscopy and gas chromatography-mass spectrometry (MS) were performed to characterize the zirconia primer.</p><p><b>RESULTS</b>Group C presented the lowest SBS, whereas groups R, ZC, and ZR presented the highest values. Thermocycling had no effect on SBS. FT-IR results showed that Z-Prime Plus contained a benzene ring and a carbonyl group. MS analysis showed that Z-Prime Plus contained 2-hydroxyethyl methacrylate, triethylamine.</p><p><b>CONCLUSION</b>Zirconia primer and self-adhesive resin cement increase the resin bonding of zirconia.</p>


Assuntos
Humanos , Adesivos , Óxido de Alumínio , Compostos Benzidrílicos , Bis-Fenol A-Glicidil Metacrilato , Resinas Compostas , Colagem Dentária , Cimentos Dentários , Metacrilatos , Cimentos de Resina , Resistência ao Cisalhamento , Silanos , Espectroscopia de Infravermelho com Transformada de Fourier , Zircônio
11.
International Journal of Biomedical Engineering ; (6)2006.
Artigo em Chinês | WPRIM | ID: wpr-558730

RESUMO

Full ceramic restorations become more and more popular for their excellent properties. Bond strength between ceramic and composite resin cement is the key factor to success in clinical use. This paper illuminated the importance of ceramic surface treatments and reviewed recent progresses on ceramic surface treatments. The difference of bond strength caused by different dental materials was discussed too.

12.
Journal of Chinese Physician ; (12)2001.
Artigo em Chinês | WPRIM | ID: wpr-526486

RESUMO

0.05),and there was significant difference in ICA,VP,RI,AT,and the levels of TXB_2 and 6-K-PGF_(1?) of the blood plasma(P

13.
Journal of Practical Stomatology ; (6)1995.
Artigo em Chinês | WPRIM | ID: wpr-670971

RESUMO

Objective:To evaluate the effects of surface modification with different concentration silica sol through sol-gel processing on bond strength between dental zirconia ceramic and resin cement. Methods:Silica coating was prepared by colloidal silica sol with concentrations of 20%,30%,40% on dental Zirconia ceramic. 32 discs zirconia ceramic specimens were fabricated and randomly divided into four groups respectively after polishing and sandblasting.The ceramic surfaces of different groups were received different treatments:(1)silane couple agent;(2)20% silica coating and silane couple agent;(3)30%silica coating and silane couple agent;(4) 40% silica coating and silane couple agent. Each ceramic block was bonded to light curing composite resin. All samples were stored in distilled water at 37 degrees for 24 h before a shear bond test to measure the bond strength of the resin cement to the ceramic surface. Scanning electrical microscopy (SEM) and energy depressive spectrum (EDS) were used to analyze the silica coating. Results:Contents of surface silicon increased after modification with silica coating prepared by sol-gel method. Bond strengths of groups with silica coating were significantly higher(P

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