1.Effects of cooling rate on the bonding strength of cast titanium to porcelain
Ruobing ZHANG ; Yumei ZHANG ; Shaopeng QI
Journal of Practical Stomatology 2001;0(03):-
Objective:To study effects of the cooling rate on the bonding characteristics of titanium porcelain bonded to cast titanium.Methods:According to ISO 9693,24 cast titanium plates(25 mm?3 mm?0.5 mm)were prepared.The middle of the samples(8 mm?3 mm) were bonded with bonding porcelain,opaque porcelain and dentin porcelain.The specimens from each porcelain-metal combination group were randomly assigned into four experimental cooling rate conditions,namely cooling rate of 15,40,50 and 100 ℃/min.A three-point-flexure-test was used to evaluate the bonding strength of titanium porcelain bonded to cast pure titanium.SEM/EDS were taken to characterize the failed surface of the titanium-porcelain interface.Statistical analyses were made by one-way analysis of variance(ANOVA).Results:The bonding strength of 15 ℃/min group was significantly higher than other groups.There were no significant differences in bond strength between 40 ℃/min and 50 ℃/min groups.SEM/EDS revealed that with an increase cooling rate,the remained porcelains on the titanium side were decreased.Conclusion:The 15 ℃/min cooling rate might be an effective method to improve the titanium-porcelain bonding strength.
2.Application of amplitude of low-frequency fluctuation to heroin abuser: a resting state fMRI study
Yinbao QI ; Xianming FU ; Changxin WANG ; Ruobing QIAN ; Xiangpin WEI
Chinese Journal of Behavioral Medicine and Brain Science 2011;20(2):119-121
Objective To study the changes of amplitude of low-frequency fluctuation (ALFF) of the resting state fMRI in heroin abuser (HD), and discussed its underlying neurophysiological mechanism.Methods The resting state fMRI data of 15 heroin abusers and 15 normal volunteers were analyzed by ALFF.The amplitude of the blood oxygenation level dependent activation of the resting state brain was investigated.The brain structures showing increased and decreased ALFF in TLE patients were demonstrated by comparing to normal subjects with 2-sample t -test with threshold of P<0.05.Results Compared with normal subjects,the regions showing decreased ALFF in HD patients were distributed in right temporal lobe(45, - 30, -21 ) ,left hippocampus( - 36,- 33, - 6), right thalamus ( 24, - 12,27 ), left posterior cingulum gyrus ( - 15, - 54,24 ), right parietal lobe /precuneus ( 21, - 51,36 ), right inferior parietal lobule ( 21, - 48,78 ) and dorsal lateral aspect of the right frontal lobe(21, - 48,78) ,while ALLF of left(45, - 42,63 ) lateral frontal cortex(0 ,39,72) in HD patients was significantly higher.Conclusion HD shows abnormal brain functional organization in resting state, which may play an important role in the production, maintenance and relapse after withdrawal of heroin abuse.
3.Effects of three bond agents on bond strength of titanium- ceramic system
Fei TAN ; Yumei ZHANG ; Ruobing ZHANG ; Shaopeng QI
Journal of Practical Stomatology 2010;26(2):160-164
Objective:To evaluate the effects of three bond agents on bond strength of titanium- ceramic system. Methods: The pure titanium specimens were randomly divided into three groups. Three different manufacturers' porcelains(Super Ti22,Duceratin,Titankeramik) were used specially for titanium- ceramic bonding. The specimens in each group were further divided into two subgroups:bond agent group and no bond agent group. Bond strength of specimens was measured by the three- point bending test according to ISO9693. The titanium- ceramic interfaces were investigated by SEM/EDS. Results:The bond strength of Super Ti22(35.84±2.17) MPa and Duceratin(35.45±2.37) MPa with bond agent group was significantly higher than that of no bond agent group(P<0.05). Titankeramik with bond agent group showed a little higher bond strength than without bond agent, but no significant difference in statistics(P>0.05). The interfaces of Super Ti22 and Duceratin with bond agent groups were compact, while there were visible cracks and pores at the interface of other groups. Conclusion:The application of bond agent can improve bond strength of titanium- ceramic system.
4.Effects of electrolyte's concentration at micro-arc oxide treatment on the bonding strength of titanium to porcelain
Shaopeng QI ; Yumei ZHANG ; Jianxue LI ; Ruobing ZHANG ; Yong HAN
Journal of Practical Stomatology 2009;25(6):833-837
Objective; To evaluate the influence of electrolyte's concentration at micro-arc oxide treatment on the bonding strength of titanium to porcelain. Methods; CP titanium specimens with size of 25 mm ×3 mm ×0. 5 mm were treated with micro-arc oxidation (MAO) in Na_2SiO_3 solution of three different concentrations. After ultra-low-fusing porcelain was applied, a three-point-flexure-test was used to evaluate the bonding strength of titanium to porcelain. The surface of the specimens was observed by SEM and EDS, as well as the interface between titanium and porcelain. Results; The bonding strength values between titanium treated with MAO and porcelain was significantly higher then the control groups, Croup 20 g/L has the highest bonding strength values. SEM/EDS suggested that a porous thin layer of oxide which contains Si element is created by MAO, and higher concentration of Na_2SiO_3 leads to more Si element in oxide. Conclusion; MAO treating can improve the bonding strength between titanium and ceramic. Electrolyte's concentration has an effect on the bond strength between titanium and porcelain.
5.Effects of three bond agents on bond strength of titanium-ceramic system
Fei TAN ; Yumei ZHANG ; Ruobing ZHANG ; Shaopeng QI
Journal of Practical Stomatology 1996;0(02):-
Objective:To evaluate the effects of three bond agents on bond strength of titanium-ceramic system.Methods:The pure titanium specimens were randomly divided into three groups.Three different manufacturers' porcelains(Super Ti22,Duceratin,Titankeramik)were used specially for titanium-ceramic bonding.The specimens in each group were further divided into two subgroups:bond agent group and no bond agent group.Bond strength of specimens was measured by the three-point bending test according to ISO9693.The titanium-ceramic interfaces were investigated by SEM/EDS.Results:The bond strength of Super Ti22(35.84?2.17)MPa and Duceratin(35.45?2.37)MPa with bond agent group was significantly higher than that of no bond agent group(P0.05).The interfaces of Super Ti22 and Duceratin with bond agent groups were compact,while there were visible cracks and pores at the interface of other groups.Conclusion:The application of bond agent can improve bond strength of titanium-ceramic system.
6.Changes of serum soluble apoptosis factors and their relations with cognition disorders in the patients with vascular dementia
Ruobing QI ; Binhua CHEN ; Zhonglin TAN ; Zhen YU ; Ziming XU ; Waner ZHU ; Xueqian SU
Chinese Journal of Geriatrics 2012;31(3):205-207
Objective To investigate the changes of serum soluble factor-related apoptosis (sFas) and soluble Fas ligand (sFasL) and their relations with cognition disorders in the patients with vascular dementia (VaD). Methods Serum concentrations of sFas and sFasl were detected by enzyme-linked immunosorbent assay (ELISA) and compared between 70 patients with VaD aged (72.5± 7.5)years and 50 healthy elderly people aged(72.5 ± 7.5)years.The VaD patient's cognitive functions were evaluated by activity of daily living scale (ADL),mini mental state examination (MMSE) and hachinski ischemia score (Hachinski). Results The serum levels of sFas and sFasL in VaD patients were (228.0±60.7)μg/L and (146.8±30.1)μg/L,and in the healthy elderly were (62.4±22.6)μg/L and (82.3 ± 18.7)μg/L,respectively.The serum levels of apoptosis factors in VaD patients were significantly higher than in the healthy controls (t=20.883,14.453,P<0.01).sFas level was negatively correlated with age,the scores of ADL and Hachiuski while positively with the scores of MMSE (r=-0.956,-0.943,-0.950 and 0.904,all P<0.01). sFasL level was negatively correlated with the scores of MMSE while positively with age,the scores of ADL and Hachinski (r=-0.899,0.963,0.948 and 0.939,a11 P<0.01). Conclusions Apoptosis may be involved in the pathological change during VaD and the serum levels of sFas and sFasL might be related with cognition disorders.
7.Identification of main related substances in potassium sodium dehydroandrographolide succinate
Xiaowei LIU ; Yuan FANG ; Qi WANG ; Rui LI ; Junjie TAN ; Ruobing CHAO
Acta Pharmaceutica Sinica 2010;45(5):641-6
To identify the structure of three related substances in potassium sodium dehydroandrographolide succinate (PSDS), an HPLC preparation method was used to separate the impurities. These main impurities were identified using LC-ESI/TOFMS, LC-ESI/MSn, NMR, UV and IR. One of the main impurities was a hydrolyzed and oxidized product of PSDS, which has not been reported previouely. The other two impurities were hydrolyzed products of PSDS after losing different succinic acids. The results indicate that PSDS can be easily hydrolyzed and oxidized. It should be stored at cool and dry places.
8.Efficacy and safety of hydrochloridememantine or donepezil combined with risperidone in treatment of Alzheimer′s disease patients with behavioral and psychological symptoms
Ruobing QI ; Mingfen SONG ; Binhua CHEN ; Yongxiu YANG ; Xiaowen YIN ; Xueping ZHANG
Chinese Journal of General Practitioners 2021;20(7):777-780
One hundred Alzheimer′s disease (AD) patients with behavioral and psychological symptoms of dementia (BPSD) treated with donepezil+risperidone group ( n=50, group 1) or hydrochloride memantine+risperidone group ( n=50, group 2) in geriatric departments of Hangzhou Seventh People′s Hospital were enrolled in the study. Montreal cognitive assessment scale (MoCA), positive and negative syndrome scale (PANSS), treatment emergent symptom scale (TESS) were applied for evaluation; and blood routine examination, blood biochemistry, eletrocardiogram were performed in two groups before and after treatment. After treatment, MoCA score in group 2 (16.10±3.90) was significantly higher than that in group 1 (18.14±3.71)( t=-3.99, P<0.01), and PANSS score in group 2 (86.66±6.62) was significantly lower than that in group 1 (109.50±11.51; t=12.67, P<0.01). The incidence rates of dry mouth (16%,8/50), extrapyramidal side effects (10%,5/50) and the total score of TESS (3.92±2.02) in group 2 were markedly lower than those of group 1 [44%(22/50), 36%(18/50), (12.49±1.45);χ 2=9.33,9.54, t=17.90,all P<0.01]. Meanwhile, group 2 had significantly lower influences on the levels of blood lipids and fasting blood glucose (all P<0.01). The risperidone dose used in group 2 was significantly lower than that in group 1 [(2.06±0.50) vs. (3.85±0.89)mg, t=14.40, P=0.04].The results suggest that hydrochloridememantine combined with risperidone is more effective with less side effects compared to donepezil combined with risperidone for AD patients with BPSD.
9.Clinical value of sleep characteristics in distinguishing mild cognitive impairment from Alzheimer′s disease
Ruobing QI ; Jia WEI ; Fei XIE
Journal of Chinese Physician 2022;24(9):1345-1348,1353
Objective:To observe the sleep characteristics of mild cognitive impairment (MCI) patients and Alzheimer disease (AD) patients, and to evaluate their values in distinguishing MCI and AD.Methods:50 patients with MCI and 50 patients with AD diagnosed in Hangzhou Seventh People′s Hospital from June 2020 to March 2022 were recruited in this study. All-night polysomnography (PSG) was performed for each patient. The total sleep time (TST) , proportion of sleep structure (N1%, N2%, N3%, REM%) , sleep efficiency (SE), sleep latency (SL), rapid eye movement sleep latency (REML), wake time after sleep onset (WASO), sleep spindle density (ρ spindle) and sleep k-complex density (ρ KC) were compared between the two groups. The indexes of sleep characteristics with statistical significance between the two groups were included to perform logistic stepwise regression. The single-factorial and multi-factorial prediction models were established. Receiver operating characteristic (ROC) curve was used to compare the value of single-factorial model and multi-factorial model in distinguishing MCI and AD patients. Results:There were statistically significant difference in TST, N3, SE, ρ spindle between MCI and AD groups ( t=3.315, 2.798, 3.682, 6.488, all P<0.05). Logistic stepwise regression analysis showed that N3, SE, ρ spindle was included in the modeling portfolio, and the joint prediction model was Logit (pre)=-19.972-0.269N3-0.141SE-3.303 ρ spindle. The sensitivity of N3, SE, ρ spindle and multi-factorial model for distinguishing MCI and AD was 64%, 32%, 96%, 90%, and the specificity was 58%, 98%, 50%, 76%, respectively. The area under the ROC curve (AUC) of the multi-factorial model and multi-factorial model were 0.639, 0.684, 0.810 and 0.901, respectively. The AUC of multi-factorial model was significantly better than that of single-factorial models ( P<0.05). Conclusions:In AD suspected population, the multi-factorial prediction model based on N3, SE and ρ spindle has a certain predictive value in distinguishing MCI and AD. Comprehensive judgment combined with the prediction model is helpful to improve the scientificity and accuracy of diagnosis.
10.Remote programming after vagus nerve stimulation in refractory epilepsy
Yinbao QI ; Dong ZHANG ; Lanlan WANG ; Xianming FU ; Ruobing QIAN
Chinese Journal of Neuromedicine 2021;20(9):932-935
Objective:To explore the efficacy of remote programming after vagus nerve stimulation (VNS) in patients with refractory epilepsy.Methods:Thirty-four patients who received VNS in our hospital from October 2019 to October 2020 were chosen in our study. Among them, 19 patients accepted remote programming (remote programming group) and 15 patients regularly came to the outpatient clinic for regulation (outpatient regulation group). The seizure frequency, response rate (seizure frequency decreased by≥50%), McHugh grading, and incidence of postoperative complications between the 2 groups were compared 6 months after VNS.Results:The seizure frequency in the remote programming group and outpatient regulation group was 2 (0, 4) times/month and 4(1, 24) times/month, without significant difference ( Z=-1.602, P=0.105). The proportion of patients enjoying effective treatment in the two groups was 13/19 and 8/15, without significant difference ( P=0.781). Results of McHugh grading showed no significant difference between the two groups ( Z=-0.728, P=0.467). The proportion of patients with postoperative complications in the two groups was 3/19 and 2/15, without significant difference ( P=0.625). Conclusion:The remote programming after VNS is safe and effective, which can become an important complementary approach for outpatient regulation.