Objective:To study the residual stress distribution through the thickness of bilayered dental ceramic subjected to thermal stress, in order to improve the restoration. Methods: The finite element model of bilayered dental ceramic was set up based on International Organization for Standardization(ISO) 96936:1999. The residual stresses were calculated in viscoelastic and elastic phases during cooling of dental ceramic to analyze the residual stress distribution. Results: The deformation of core was greater than the veneer ceramics during the cooling period of dental ceramic. The residual stress increased with the decreasing of the temperature approaching the interface of core and veneer ceramics. But it decreased with the increasing of the thickness of veneer ceramics.Conclusion: Thermal compatibility of core and veneer ceramics is very important to the residual stress distribution in the bilayered dental ceramic, which may benefit to All-ceramic restorations. The viscoelastic behavior of ceramic should be taken into account in the thermal compatibility.

Lymphoma is a malignant tumor of the lymphatic system, including Hodgkin's lymphoma and non-Hodgkin's lymphoma. Lymphoma is the fourth most common primary malignant tumor during pregnancy and one of the major malignant diseases affecting maternal and infant outcomes. This review summarizes the clinical features, diagnosis, maternal and fetal outcomes, and clinical lymphoma treatment during pregnancy. It is suggested that clinicians should pay attention to the symptoms, including unexplained lymphadenectasis, systemic symptoms, extranodal lesions, and the　symptoms of pressure exerted on the involved local organs, especially those in the breast and reproductive system, and make a timely diagnosis in line with the biopsy or puncture results. Management should be based on the classification, stage, and clinical manifestations of lymphoma. Besides, the gestational age at diagnosis, maternal and child conditions, and the willingness to continue the pregnancy should also be considered. Most mothers and their children can have good outcomes after individualized treatment through multidisciplinary cooperation and close perinatal management.

Prosthodontics is an important undergraduate course in stomatology. It's an unprecedented challenge for teachers to give theoretical lectures completely by online teaching methods. After several months of online teaching practice, a complete closed-loop online teaching mode of "pre-class, in-class and after-class" has been formed by using online teaching tools such as Tencent meeting, Superstar learning platform and WeChat. A comprehensive feedback and assessment mechanism has also been established. On the premise of the teaching quality, online teaching has also promoted the exploration and reform of the information-based teaching of prosthodontics course.

Objective To investigate the dynamic mechanical responses and damage characteristics of peri-implant bone structures subjected to impact load.Methods A finite element model of the peri-implant bone microstructure was established,and an initial velocity was applied to the rigid body to simulate the impact load.A stress failure criterion was employed and a user-material subroutine was developed to assess failure.Subsequently,bone damage after the impact load was analyzed according to the material subroutine.Results After the impact load,the stress on the cortical bone increased rapidly,reaching a peak value(16.01 MPa)immediately.In contrast,the stress on the trabecular bone at the bottom of the implant reached its peak value(5.85 MPa)at 0.1 μs.The impact load resulted in stress waves that propagated and diffused within the bone structure,causing changes in the bone structure damage over time.The generated impact energy could be absorbed and dissipated by the trabecular bone through deformation.The deformed trabecular bone experienced damage and failure upon reaching the yield limit,whereas the cortical bone did not experience damage or failure under an impact load.Conclusions Structural changes in the trabecular bone should be considered in patients with impact damage.The numerical model established in this study can effectively predict bone impact damage by combining the structural mechanical properties and geometric characteristics of the bones.These findings can serve as a reference for assessing bone damage and post-damage treatment in patients subjected to impact loads in clinical practice.

OBJECTIVE: To investigate the effects of centella asiatica (CA) granule on the expression of transform growth factor-β(TGF-β) and related down-stream signals in rats with early diabetic nephropathy(DN) and to clarify the molecular mechanisms of CA molecular mechanism of on preventing and curing early diabetic kidney disease DN by studying the effects of centella asiatica on TGF-β expression and related down-stream signals. METHODS: Sixty male SD rats were divided into control group(=10) and DN model group(=50). The model rats were made a right nephrectomy. One week later, diabetic nephropathy was induced by intraperitoneal injection of streptocozin(30 mg/kg) for three consecutive days. High blood glucose level of Tail vein (fasting glucose ≥ 16.7 mmol/L) and high urinary protein level(total protein level in DN group was more than twice higher than the control group) were measured to confirm early DN in rats. In the sham operation group, the right renal capsule was damaged and the corresponding amount of saline was injected. The model rats were administrated by the means of intragastric administration. The DN model group were divided into DN group, DN+fosinopril group(1.6 mg/kg·d), DN+high CA group(16.8 mg/kg·d), DN+medium CA group(11.2 mg/kg·d) and DN+low CA group(5.6 mg/kg·d), and each group was intragastric administration one time every morning last for 16 weeks. The expressions of mRNA and protein of TGF-β, TβR1, TβR2, Smad2/3, Smad7 and the level of Smad2/3 phosphorylation were detected by using real time quantitative polymerase chain reaction and Western blot. RESULTS: The expressions of mRNA and protein of TGF-β, TβR1, TβR2, Smad2/3 and the level of Smad2/3 phosphorylation were significantly increased, the expressions of mRNA and protein of Smad7 were dramatically decreased. The fosinopril and high dosage CA could reverse the effects of DN. CONCLUSIONS CA plays an important role in preventing and curing DN through regulating the TGF-β/Smad signaling pathways.
Animals ; Centella ; chemistry ; Diabetes Mellitus, Experimental ; Diabetic Nephropathies ; chemically induced ; drug therapy ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Kidney ; physiopathology ; Male ; Rats ; Rats, Sprague-Dawley ; Receptor, Transforming Growth Factor-beta Type I ; metabolism ; Receptor, Transforming Growth Factor-beta Type II ; metabolism ; Signal Transduction ; Smad2 Protein ; metabolism ; Smad3 Protein ; metabolism ; Smad7 Protein ; metabolism ; Transforming Growth Factor beta1 ; metabolism

OBJECTIVES: Stably expressed transforming growth factor -beta 1(TGF-β1)MCs were obtained and the effects of centellaasiatica (CA) granule on the expressions of Smad 2/3, Smad 7 and collagen Ⅳ and the level of Smad 2/3 phosphorylation were observed. METHODS: Lipofectin method was used to transfect TGF-β1 vector into MC, and the stably expressed TGF-β1 cell lines were selected by G418. The cells were divided into three groups. Control group:normal MC + RPMI 1640 + 10% normal rat serum; TGF-β1 group:stably expressed TGF-β1 MC + RPMI 1640 + 10% normal rat serum; CA group:stably expressed TGF-β1 MC + RPMI 1640 + 10% rat serum containing high CA. The experiments were repeated for five times. The contents of TGF-β1 and collagen Ⅳ in the culture medium were detected with ELISA, the expressions of mRNA and protein of TGF-β1, Smad 2/3, Smad 7 and the level of Smad 2/3 phosphorylation were detected by using real time quantitative polymerase chain reaction and Western blot. RESULTS: The contents of TGF-β1 and collagen Ⅳ in the culture medium of stably-expressed TGF-β1 MC were increased significantly, and the CA could reverse the effects of TGF-β1. The expressions of mRNA and protein of TGF-β1, Smad 2/3 and the level of Smad 2/3 phosphorylation were increased significantly in TGF-β1 transfected MC, and CA could dramatically reduce the expressions of mRNA and protein of TGF-β1, Smad 2/3 and the level of Smad 2/3 phosphorylation. The high expression of TGF-β1 decreased the expression of Smad 7 mRNA and protein, and the CA could antagonize the effect of mRNA expression. CONCLUSIONS The MCs stably-expressed TGF-β1 can activate the TGF-β1/Smad signal pathway and increase the expression of collagen Ⅳ. CA can decrease the occurrence of diabetic nephropathy(DN) by reducing the production of collagen Ⅳ through inhibiting the TGF-β1/Smad signal pathway.
Animals ; Cells, Cultured ; Centella ; chemistry ; Collagen Type IV ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Mesangial Cells ; drug effects ; metabolism ; Rats ; Signal Transduction ; Smad Proteins ; metabolism ; Smad2 Protein ; metabolism ; Smad3 Protein ; metabolism ; Smad7 Protein ; metabolism ; Transforming Growth Factor beta1 ; metabolism

Objective:To investigate the change of chemical exchange saturation transfer (CEST) imaging in the bilateral substantia nigra (SN) and red nucleus (RN) of Parkinson disease (PD), and to explore the value of CEST-MRI for the clinical application of PD.Methods:This was a cross-sectional study. A total of 45 PD patients (PD group) and 21 sex-, age-, and cognitive-function matched normal control subjects (NC group) were retrospectively enrolled from December 2012 to July 2015 in Beijing Hospital. All subjects underwent brain CEST-MRI and routine MRI. Based on the MATLAB software package, the 4-pool Lorentz fitting model was applied to analyze the signal change of CEST imaging, which could acquire the mean amplitudes of the 4-pool parameters including Amide, nuclear overhauser enhancement (NOE), direct water saturation (DS) and magnetization transfer (MT) in the bilateral SN and RN. Independent samples t test and Mann-Whitney U test were used to compare CEST parameters between the PD group and the NC group and controlled by Bonferroni correction. The combined model was constructed based on parameters with inter-group differences after correction. The receiver operating characteristic curve and area under the curve (AUC) were used to evaluate the diagnostic efficiency of the CEST parameters and the combined model. Results:Compared with the NC group, the left SN Amide value, left RN Amide value, and right SN NOE value were reduced in the PD group, and the difference was statistically significant ( t=-3.59, corrected P=0.026; t=-3.77, corrected P=0.016; Z=-3.27, corrected P=0.017). The left SN Amide value, the left RN Amide value, the right SN NOE value, and the combined model all had good diagnostic efficacy in the differentiation of the PD group from the HC group (AUCs of 0.78, 0.79, 0.75, and 0.81, respectively). The combined model had the highest AUC value (0.81) and specificity (97.78%), the Amide value of left SN had the highest sensitivity (93.33%). Conclusions:Quantitative analysis of CEST-MRI based on the 4-pool Lorentz fitting model shows significant differences in the CEST quantitative indicators of the SN and RN between the PD group and the NC group, demonstrating good potential for clinical application in the diagnosis of PD.

Antineoplastic Agents ; Dasatinib ; Humans ; Leukemia, Myeloid, Chronic-Phase/drug therapy* ; Protein Kinase Inhibitors ; Pyrimidines/therapeutic use*

【Objective】 To analyze the HIV-, HCV- and HBV- NAT yield rate in different areas of Henan province, so as to provide the basis for disease prevention and control as well as the establishment of a unified quality control standard for nucleic acid testing(NAT) in the Henan province. 【Methods】 The number and prevalence of NAT yielding samples with isolated infectious virus, namely HIV, HCV and HBV, in 18 blood stations in Henan province from 2017~2019, as well as the trends were analyzed. The NAT quality of each laboratory and each testing system was analyzed according to the ratio of reactive individual donation(ID) results to reactive minipools(MP). 【Results】 The HBV, HCV and HIV ID-NAT yield numbers in 3 501 251 blood donations were HBV 2 606(74/100 000), HCV 21 (0.63/100 000), and HIV 34(1.00/100 000). The HBV ID-NAT yield rate showed an upward trend in the whole province from 2017 to 2019, while the prevalence of HIV and HCV ID-NAT yield didn′t differ significantly during three years. 5 kinds of NAT detection systems were applied in 18 blood centers. among which Ⅰ, Ⅱ, Ⅳ and Ⅴ were triplex detection systems. 2661 ID-reactive samples were implicated in 5 595 MP-reactive samples, with a resolution rate of 47.56%. The resolution rate of triplex NAT system Ⅰ, Ⅱ, Ⅳ and Ⅳ was 39.63%~47.95%, 40.43%~54.36%, 51.61% and 70.00%~45.45%, respectively. An upward trend in triplex NAT resolution rate was observed in 8 laboratories, i. e.B, D, E, F, I, K, L and Q, and an descending trend in A and C. The NAT system Ⅲ, a ID-NAT system, was used only by laboratory C, presenting a NAT-yield rate of 0.19% (282/145 474) and resolution rate of 46.45% (131/282). 【Conclusion】 The majority of NAT-yield of one infectious virus in Henan province is HBV, presenting annual increasing trend. The quality management of NAT laboratories should be strengthened as the divergence was seen in the performance of different NAT laboratories.

【Objective】 To analyze the cause of single-ELISA reactive of four blood screening items in 18 blood stations in Henan, so as to provide the basis for improving the quality of blood screening. 【Methods】 The single-ELISA reactive rate of HBsAg, anti-HCV, HIV Ag/Ab and anti-TP of 18 blood station laboratories in Henan throughout 2019 was calculated, and the causes were analyzed according to different ELISA reagent combinations and gray area settings in each laboratory. 【Results】 The overall single-ELISA reactive rates of HBsAg, anti-HCV, HIV Ag/Ab and anti-TP were 1.740(2 154/1 237 789), 0.564‰(698/1 237 789), 1.421‰(1 759/1 237 789) and 1.561‰(1 932/1 237 789), respectively, showing significant differences by detection items (P <0.05). Person correlation analysis showed that the single-ELISA reactive rate was independent of the gray area settings.but dependent on laboratories and reagent combinations. The single-ELISA reactive rate of HBsAg, anti-HCV, HIV Ag/Ab and anti-TP in D laboratory was the highest and higher than that in other labs using the same reagent.The laboratories with high HBsAg single-ELISA reactive rate were mostly those using a combination of imported reagents and domestic reagents, including the top 6 laboratories. The laboratories with high anti-HCV single-ELISA reactive rate were mostly those using certain domestic reagents. No obvious rules was noticed by single-ELISA reactive for anti-HIV. Laboratories with high anti-TP single-ELISA reactive rate were mostly those using combination 4. 【Conclusion】 The HBsAg single-ELISA reactive rate was the highest in the four blood screening items of blood station laboratories in Henan. The single-ELISA reactive rate is related to the laboratory itself and the reagent manufacturer, suggesting that laboratory quality control should be strengthened and proper reagent combination should be selected to reduce the waste of blood.