Objective:To evaluate the effects of Er,Cr:YSGG laser combined with NaF treatment on the acid resistance of human dental hard tissue.Methods:The enamel or dentin samples were randomly divided into four groups and prepared by different methods as follows: ①without treatment(control group),②laser irradiation(Laser group),③ treated with 20 g/L NaF solution(NaF group),④laser irradiation+ NaF solution treatment(Laser and NaF group).The samples of each group were respectively demineralized in 0.1 mol/L of lactic acid for 24 h and the calcium ion in the demineralization solution in each group was measured by atomic absorption spectrophotometry.The fluoride on the surface of the samples was examined by SED-X and the ultrastructure was investigated by SEM.Results:The concentrations of Ca~(2+) dissolved from the enamel or dentin samples in NaF,laser and NaF and laser groups were significantly lower than that in the control group(P(0.05)).Only in the NaF group,the F peak appeared.SEM observation showed the lased surface showed various patterns of microirregulation with a scaly appearance,the openings of dentinal tubules were visible,but no melting or carbonization;there were lot of particles attached to the surface of NaF treated samples;the ultrastructure of the NaF and laser-treated sample surfaces was similar to that of the laser treated.Conclusion:The combined use of laser and NaF dose not have synergetic effects on acid resistance of human dental hard tissue.

0.05).SEM revealed that the lased enamel surface appeared various patterns of microirregularity, and there was no smear layer.Conclusion:Laser irradiation can be used to prepare the enamel before placing pit and fissure sealant.

Objective To evaluate the expression of Sp3 gene of peripheral blood mononuclear cells (PBMC) in multiple sclerosis (MS) patients and the correlation between Sp3 gene expression and clinical manifestation Methods Two pairs of primers were used to amplify cDNAs generated from 33 MS patients and 90 controls including healthy controls, other nonimmunological neurological disease controls and the other neuroimmunological diseases than MS controls Results The deficient expression of Sp3 gene in MS patients (45%, 15/33) is statistically significantly higher than that in the other 3 control groups ( P

Objective To evaluate the effect of local mild hypothermia on the expression of phosphatase and tensin homolog deleted on chromo-some ten (PTEN) protein during global cerebral ischemia-reperfusion (I/R) in rats.Methods One hundred and eight healthy adult male Wistar rats,weighing 230-280 g,were randomly divided into 3 groups (n =36 each) using a random number table:sham operation group (group S),cerebral I/R group (group I/R) and mild hypothermia cerebral I/R group (group HI/R).Global cerebral I/R was induced by 4-vessel occlusion method described by Pulsinelli.Bilateral vertebral arteries were permanently occluded by cauterization,and bilateral carotid arteries were occluded for 15 min.Nasopharyngeal cooling was applied and the nasopharyngeal temperature was reduced to 32.5-33.5 ℃ and maintained at this level for 1 h.When the nasopharyngeal temperature was reduced to 32.5-33.5 ℃,the bilateral carotid arteries were clamped in group HI/ R.Six rats were chosen to be anesthetized and sacrificed immediately before ischemia and at 4,8,12,24 and 72 h of reperfusion.Hippocampal specimens were obtained to detect the expression of phosphorylated PTEN (pPTEN),Bcl-2 and Bax protein (by immunohistochemistry) in hippocampal CA1 region,contents of S100B protein (by ELISA) and MDA (by thiobarbituric acid method),and activity of SOD (by xanthine oxidase method).Results Compared with group S,the expression of p-PTEN and Bcl-2 protein,ratio of Bcl-2/Bax protein and activity of SOD were significantly decreased,and the expression of Bax protein and contents of MDA and S100B protein were increased after reperfusion in group I/R (P ＜ 0.05),and the ratio of Bcl-2/Bax protein was decreased,and there was no significant difference in the expression of p-PTEN,Bcl-2 and Bax protein,activity of SOD and contents of MDA and S100B protein after reperfusion in group HI/R (P ＞ 0.05).Compared with group I/R,the expression of p-PTEN and Bcl-2 protein,Bcl-2/Bax ratio and activity of SOD were significantly increased and the expression of Bax protein and content of MDA and S100B protein were decreased after reperfusion in group HI/R (P ＜ 0.05).Conclusion The mechanism by which local mild hypothermia reduces cerebral damage is related to inhibition of activation of PTEN protein in the brain tissues during global cerebral I/R in rats.

OBJECTIVEThe purpose of this study was to evaluate the morphological changes of Er, Cr: YSGG laser irradiated dental hard tissues by scanning electron microscopy (SEM).

METHODS12 freshly extracted premolars were treated with fissure bur, Er, Cr: YSGG laser at 4 watt, Er, Cr: YSGG laser at 6 watt, respectively, and then bisected transversally and longitudinally. The tooth slice were prepared with conventional methods and observed by SEM.

RESULTSCompared with fissure bur, laser treatment resulted in a rather scaly and rough surface. The sections were free of smear layer, with open dentinal tubules. No carbonization and thermal damages were observed. The laser at 6 watt appeared rougher than at 4 watt, occasionally caused micro-cracks.

CONCLUSIONThe utilizing of Er, Cr: YSGG laser can contribute to enhance the bond strength between restorative materials and dental hard tissues. It suggests that higher energy could be applied in cutting enamel, whereas the lower energy in dentin.

Dental Cavity Preparation ; instrumentation ; methods ; Dental Enamel ; radiation effects ; ultrastructure ; Dental High-Speed Equipment ; Dentin ; radiation effects ; ultrastructure ; Hardness ; Humans ; In Vitro Techniques ; Lasers ; Microscopy, Electron, Scanning ; Tooth ; radiation effects ; ultrastructure

Objective To study the correlation of whole brain apparent diffusion coefficient (ADC) with neurological impairment,homocysteine (Hcy) metabolism and oxygen free radical generation in patients with Alzheimer's disease (AD).Methods The patients diagnosed as AD in Xuanwu Hospital of Capital Medical University from March 2014 to December 2017 were selected as AD group and healthy persons as control group.The ADC of whole brain was calculated after magnetic resonance scanning.The degree of neurological impairment was evaluated by Montreal Cognitive Function Assessment Scale (MoCA).The levels of Hcy metabolic index and oxygen free radical production were measured after collecting serum.Results ADC values of AD group in parietal lobe,frontal lobe,temporal lobe and occipital lobe were not significantly different from those of control group (P ＞ 0.05).The ADC value of hippocampus as well as serum Hcy,malondialdehyde (MDA) and nitric oxide (NO) contents were significantly higher than those of control group,while MoCA score as well as folic acid (FA),vitamin B12 (VitB12),superoxide dismutase (SOD) and glutathione peroxidase (GSH) contents in serum were significantly lower than those of control group (P ＜ 0.05);ADC value of hippocampus in AD patients was negatively correlated with MoCA score as well as serum FA,VitB12,SOD and GSH contents,and positively correlated with serum Hcy,MDA and NO contents.Conclusions The increased ADC value of hippocampus in AD patients was related to the cognitive function injury,Hcy metabolism disorder and excessive generation of oxygen free radicals.

Objective:To investigate the correlation between activities of daily living and hemoglobin level in patients with acute ischemic stroke (AIS).Methods:A retrospective analysis was performed in 190 patients with acute ischemic stroke from August 2015 to April 2017. The hemoglobin (Hb) levels at admission were analyzed . According to the Barthel index (BI) score, the patients were divided into good improvement group ( n=119) and poor improvement group ( n=71). Spearman correlation analysis was used to study the relationship between hemoglobin level and short-term activities of daily living in patients with acute ischemic stroke. Results:(1)The short-term activities of daily living was improved in 119 patients. Among them, 62 (52.1%) were under 65 years old and 57 (47.9%) were over 65 years old, 9 (7.56%) male patients with hemoglobin <120 g/L and 39 (32.77%) male patients with hemoglobin > 150 g/L. There were 71 patients with poor short-term activities of daily living. Among them, 23(32.39%)were under 65 years old and 48(67.61%)were over 65 years old, 1(1.41%)male patients with hemoglobin <120 g/L and 12(16.9%) male patients with hemoglobin > 150 g/L. There were significant differences in age (χ 2= 6.985, P=0.008) and male hemoglobin level (χ 2= 8.069, P=0.005) between patients with good activities of daily living and patients with poor activities of daily living.(2)Regression analysis showed that age > 65 years ( β =1.386, OR=4.000, 95% CI=1.189-3.461, P=0.025) and abnormal hemoglobin levels in men (Hb<120 g/L or > 150 g/L) ( β =1.089, OR=2.972, 95% CI=1.383-6.388, P=0.005) were the influencing factors of poor short-term quality of life in patients with acute ischemic stroke.(3)Spearman correlation analysis showed that abnormal hemoglobin levels in men (Hb<120 g/L or>150 g/L) were positively correlated with poor short-term activities of daily living in patients with acute ischemic stroke( r=0.244, P=0.004). Conclusion:Abnormal hemoglobin level is associated with poor short-term activities of daily living improvement in patients with acute ischemic stroke.

Objective:To investigate the correlation between serum 25-hydroxyvitamin D (serum 25(OH)D) and Meige syndrome.Methods:A retrospective analysis was performed on 47 patients with Meige syndrome (Meige syndrome group) treated in Yuquan Hospital of Tsinghua University admitted from August 2012 to July 2018 in our hospital.In the same period, 69 healthy people of the same age group were selected as the healthy control group.The difference of serum 25(OH)D concentration among different subtypes of Meige syndrome (type I, II, III) was compared.Logistic regression analysis was used to analyze the correlation between serum 25(OH)D level and Meige syndrome.Results:The serum 25(OH)D concentration in patients with Meige syndrome was (12.68±6.77) μg/L, which was significantly lower than that in the healthy control group ((17.93±6.93) μg/L). The difference was statistically significant ( t=4.044, P<0.001). The serum 25(OH)D concentrations of subtypes I, II and III in patients with Meige syndrome were (14.7±8.14), (11.4±5.02), (8.38±4.99) μg/L, respectively. There was no significant difference among the three types ( F=1.892, P=0.231). Logistic regression results showed that serum 25(OH)D levels were correlated with Meige syndrome ( OR=0.938, 95% CI: 0.885-0.995, P=0.034). Conclusion:The serum 25(OH)D expression level in patients with Meige syndrome is low, suggesting that vitamin D deficiency may be involved in the pathogenesis of Meige syndrome.

Objective:To assess the safety and efficacy of Anthocyanins for the treatment of Alzheimer's disease.Methods:From November 2018 to December 2020, a multicenter, double-blind, randomized controlled clinical study was conducted in 6 hospitals.The regular medication for the two groups was memantine, with the addition of a combination preparation containing Anthocyanins for the experimental group and a placebo for the control group.The Mini-Mental State Scale(MMSE), Montreal Cognitive Assessment Scale(MoCA), Alzheimer's Disease Assessment Scale-Cognitive Subscale(ADAS-cog), Activities of Daily Living Scale(ADCS-ADL)and Hamilton Depression Scale(HAMD)were used for assessment at the beginning.After 16 weeks of treatment, MMSE, MoCA, ADCS-ADL, ADAS-cog and the Clinician's Interview-Based Impression of Change Plus Caregiver Input(CIBIC-Plus)Scale were conducted and adverse events were recorded.Results:A total of 66 patients were enrolled, with 33 in the control group and 33 in the experimental group.There were no significant differences in cognitive function scores between the two groups before enrollment.Differences in MMSE scores, MOCA scores and ADAS-cog scores before and after treatment between the control group and the experimental group were 1.9±2.4 vs.3.4±2.0( t=2.62, P=0.011), 1.8±1.9 vs.2.9±1.4( t=2.45, P=0.018)and 3.0±2.3 vs.5.3±4.6( t=2.45, P=0.019), respectively.The differences were statistically significant.Instrumental activities of daily living(IADL)scores before and after treatment in the control group were 21.6±5.7 vs.22.6±6.2( t= 2.09, P= 0.046), and those in the experimental group were 22.7±5.4 vs.23.4±5.4( t= 2.45, P= 0.021). The differences between the two groups before and after treatment were statistically significant. Conclusions:Treatment with Anthocyanins can delay the decline of cognitive function and activities of daily living ability in patients with Alzheimer's disease.Anthocyanins may be a promising therapeutic drug for Alzheimer's disease in the future.

Objective:To establish a candidate reference procedure for the enumeration of cell particles in urine and applied to the multi-center performance evaluation of an automated urine formed elements analyzer.Methods:According to the standardized mannual microscopic examination of fresh non-centrifuged urine samples and the recommended reference method for enumeration of cell particles in urine published by ISLH, we established a candidate reference procedure for the enumeration of cell particles in urine. From four class A tertiary hospitals′ clinical laboratories, three rigorous trained technicians per hospital tested the same specimen respectively using the reference procedure. Each specimen was repeatedly counted 5 times, obtaining the quantitative results of cell particles were obtained in urine. Four hospitals used the established candidate reference measurement procedure and the automated urine formed elements analyzer to detect 40 to 60 urine specimens from September 2020 to January 2021, and evaluate the established reference method, meanwhile evaluate the accuracy and consistency of the each count from automated urinalysis analyzer.Results:Using the candidate reference measurement procedures, the coefficient of variation of results derived from three trained technicians per hospital was less than 6.98% (red blood cells), 6.99% (white blood cells), 13.94% (epithelial cells) and met the quality requirements. The performance evaluation results of automated urine formed elements analyzer showed that the accuracy of red blood cells, white blood cells and epithelial cells met the requirements (bias≤4.98%) and was well consistent with the reference measurement procedure ( R2≥0.989). Conclusions:A candidate reference measurement procedure for the enumeration of urine cell particles was successfully established with satisfactory precision and accuracy. This procedure was applied to multicenter performance evaluation of an automated urine formed elements analyzer with good accuracy and consistency.