Objective To investigate the effects of different cyclic tensile strain on the proliferation of human anulus fibrosus cells from degenerated discs.Methods Anulus fibrosus(AF) cells were isolated from a degenerated human IVD,expanded in monolayer,and cyclically strained for 3 hours,applying 0,5％,10％,15％ and 20％ strains at a frequency of 0.25 Hz with the use of the DioDynamic test instrument.The flow cytometry method was used to examine the Af cells proliferation at 24 hours following application of the cyclic tensile strains.Results The proliferative index (PI) increased with the magnitude value of cyclic tensile strain except 20％ group.The most significant increase of proliferation index were found in 15％ group.Conclusion There might be some corelationships between magnitude of cyclic tensile strain and the proliferation of the degenerative AF cells.

BACKGROUND:The enamel matrix derivative has been used in the clinical treatment of severe periodontitis; however, the mechanism(s) by which enamel matrix derivative promotes periodontal regeneration is stil obscure. OBJECTIVE:To explore the effects of enamel matrix derivatives on the differentiation and proliferation of periodontal ligament stem cels. METHODS:Periodontal ligament stem cels were isolated and identified from human teeth. Cloning forming efficiency, surface antigen expression and pluripotency were detected and identified. Enamel matrix derivatives with different concentrations (20, 50, 100 mg/L) were used to culture periodontal ligament stem cels for 2 and 4 weeks. Colagen synthesis and mineralized nodule formation were detected using Trichrom staining and Von Kosa’s staining, respectively; real-time RT-PCR was employed to detect expressions of colagen type I, osteocalcin, and RUX2; MTT and cel growth rate assay were used to detect the proliferation of periodontal ligament stem cels. RESULTS AND CONCLUSION:Periodontal ligament stem cels were spindle-shaped and showed a higher colony forming efficiency than periodontal ligament cels. The expressions of surface antigens of periodontal ligament stem cels-CD105, CD29, CD45, CD44 were respectively 99.8%, 99.7%, 1.26%, 98.8%, indicating periodontal ligament stem cels have the multilineage differentiation potential. Enamel matrix derivatives improve the colagen synthesis and mineralization nodule formation of periodontal ligament stem cels in a time-dose dependent manner. They also can improve the expression of osteogensis-related genes colagen type I, osteocalcin, RUX2 and proliferation of periodontal ligament stem cels.

ObjectiveTo investigate effects of anisodamine on myocardial caspase-1 and interleukin-18 expression following overtraining-induced acute myocardial injury in rats.Methods Forty-eight male Wistar rats weighing 200-220 g were randomly divided into 3 groups:group control (group C,n =8) ; group exhausting swim (group ES,n =24) and group anisodamine (group AD,n =16).The animal model of overtraining-induced acute myocardial injury was developed by exhausting swim The animals were forced to swim until they were exhausted.The animals sank to the bottom and no righting reflex or escape response was elicited when they were taken out of water in groups ES and AD.In group AD anisodamine 10 mg/kg was given intraperitoneally 20 min before overtraining.Blood samples were taken from inferior vena cava immediately (T1) and at 6 and 24 h after overtraining (T2,T3 ) in group ES and at T2,T3 in group AD for determination of serum cardiac troponin 1 (cTnI) concentration (by ELISA).The animals were sacrificed after blood sampling and myocardial specimens were obtained for microscopic examination and determination of caspase-1 and interleukin-18 expression (by immuno-histochemistry).ResultsOvertraining significantly increased serum cTnI concentration and up-regulated myocardial caspase-1 and interleukin-18 expression in group ES as compared with group C.Anisodamine significantly attenuated overtraining-induced increase in serum cTnI concentration and myocardial caspase-1 and interleukin-18 expression in group AD as compared with group ES.ConclusionAnisodamine can reduce overtraining-induced acute myocardial injury by down-regulating caspase-1 and interleukin-18 expression.

Objective To evaluate the mechanical homogeneity pattern of isolated carotid atherosclerotic plaque intima on longitudinal axis view using ultrasonic velocity vector imaging.Methods Fourty six patients with 48 isolated plaques were undergone the high frequency ultrasound scanning,the real-time two-dimensional longitudinal-axis gray scale view at the maximal thickness of the plaque was obtained in three complete cardiac cycles.A dedicated velocity vector imaging(ⅤⅤⅠ)workstation was used for the off-line dynamic two-dimensional gray-scale image analysis and mechanics parameter(i.e.,the peak strain and the absolute difference of the peak strain)assessment at the sites of the upper,middle and down stream separately.The length and direction distribution of the velocity vectors at the carotid atherosclerotic plaque intima were observed.Wilcoxon test was utilized for the comparison of the peak strain and the absolute difference of the peak strain between two sites.Results The chaos phenomenon of velocity vector distribution at the sites of plaque intima occurred significantly differed from those uniform velocity vectors at the reference sites.According to the two groups of the higher strain value side and the lower strain value side on the upper stream and the down stream of the plaque intima,the peak strain at the higher strain value side was significantly higher than the lower strain value side(P=0.000).There was a significantly difference between the absolute difference of peak strain from the higher strain value side to the middle stream point of the plaque intima and the absolute difference of peak strain from the lower strain value side to the higher strain value side of the plaque intima(P＜0.017).Conclusions The length and direction distribution of velocity vectors of the isolated carotid atherosclerotic plaque intima on longitudinal axis view are uneven,the mechanical heterogeneity pattern exists at the plaque intima and could be visualized and quantitatively evaluated using ultrasonic velocity vector imaging.

Objective:To construct the pleiotrophin (PTN )overexpression vector,and to explore the effect of PTN on the decidualization of uterine stromal cells in the mice.Methods:The specific primers containing restriction enzyme cutting sites were designed according to the PTN gene sequences published in GenBank for PCR amplification.The amplified fragment of PTN was recovered from the agarose gel and cloned into the pGEM-T vector.The pGEMT-PTN was cut by double enzyme digestion and ligated into pcDNA3.1 (+)to construct the PTN overexpression plasmid.After transfection with PTN overexpression plasmid,the expression levels of PTN mRNA in the uterine stromal cells and the expression levels of decidualization markers Prl8a2 and Prl3c1 were detected by qRT-PCR method.The uterine stromal cells transfected with pcDNA3.1 (+)empty vector were used as control group. Results:The results of identification by double enzyme digestion indicated that the bands of PTN overexpression plasmid were consistent with those of the target gene,and the clone sequencing results suggested that it had 100% homology with mouse PTN gene sequence published in GenBank.Compared with control group, the expression levels of PTN,Prl8a2 and Prl3c1 mRNA in mouse uterine stromal cells in PTN overexpression group were significantly increased (P < 0.05).Conclusion:PTN overexpression could increase the expression levels of decidualization markers in mouse uterine stromal cells,indicating that PTN might play an enhancement effect during uterine decidualization in the mice.

A method for simultaneous determination of PCDDs, dl-PCBs, BFRs and PBDD/Fs in flue gas from stationary source was developed. The sample was extracted by Soxhlet apparatus with toluene, and followed by purification through sulfuric acid partition and multi-layer silica gel column separation. The target compounds were then all separated by passing through the active carbon-dispersed silica gel column and reversal eluting. Gas chromatography coupled with a thermostable capillary column ( short length, thin stationary phase film) was operated at pulse injection mode. High resolution mass spectrometry set at low-electron-energy ionization was used for quantification. The high- and low-brominated compounds were determined simultaneously. The detection limits of this method were 0. 081-1. 2 pg for PCDD/Fs, 0. 10-0. 32 pg for dl-PCBs, 0. 14-12 pg for PBDEs, 0. 26-16 pg for new BFRs, 0. 44-3. 6 pg for tetra- to hepta-BDD/Fs and 8. 2-12 pg for OBDD/F. Recoveries ( RSDs) in spiked flue gas samples were 88%-115%(2. 9%-6. 1%) for PCDD/Fs, 84%-118% (3. 2%-10%) for dl-PCBs, 71%-135% (2. 1%-18%) for PBDEs, 71%-114% (2. 9%-7. 4%) for new BFRs, 83%-127% (5. 2%-10%) for tetra-to hepta-BDD/Fs and 52%-149% ( 23%-24%) for OBDD/F. All quality control data fell within the acceptable range specified in analysis standards for flue gas.

Patients with early cataract may have normal visual acuity ( VA ) but complain that they have problems in driving at night, like seeing things through a veil. This phenomenon is defined as disability glare which maybe caused by growing stray light. Patients with intraocular lens following cataract surgery may complain about glare, halos and shadows in visual field, which are also resulted from dysphotopia. Disability glare is the VA loss due to disturbing luminance in visual field. ln other words, it's the retinal contrast sensitivity reduction because of the straylight. This article contains the consensus and new progress of disability glare. lt provides solutions according to its effect factors and offers clues for further study.

Objective To evaluate the sensitivity and specificity of different HbA1C cutoff points for diabetes diagnosis in high risk outpatients in Harbin.Methods A total of 2 122 high risk outpatients(male 1 032 and female 1 090)for diabetes screening in the Fourth affiliated Hospital of Harbin Medical University from April 2013 to February 2015 were included in this study, with the average age of(49.26±13.00)year. Oral glucose tolerance tests(OGTT)were conducted and HbA1C levels were examined in these patients. The sensitivity and specificity of different HbA1C cutoff points were calculated and a receiver operator characteristic(ROC)curve was then built.Results The average level of HbA1C in these subjects was(6.45±1.72)%. The prevalence of diabetes was 41.85%. The area under ROC curve(AUC)was 0.89 with the optimal cutoff point of HbA1C 6.0% and 0.68 for the highest Yonden index. The sensitivity and specificity of HbA1C 6.0% were 84.01% and 83.67% respectively. The sensitivity and specificity of HbA1C 6.5% were 62.84% and 95.92%, respectively. The AUC of HbA1C≥6.5% was 0.732. Conclusion HbA1C works well as the diagnostic standard for diabetes in high risk outpatients of Harbin city. The cutoff point of HbA1C 6.0% is suitable for screening diabetes in high risk population, and HbA1C 6.5% is appropriate for diabetes diagnosis, with high sensitivity and specificity.

Abstract: Objective　To evaluate the influence of coronavirus disease 2019 (COVID-19) prevention and control measures on the transmission and epidemic of influenza in Chongqing, so as to provide references for formulating targeted influenza prevention and control strategies. Methods　The influenza surveillance data, during the year 2018 to 2020, were collected through the "China Influenza Surveillance Information System", and the seasonal characteristics of influenza epidemic were analyzed. The percentage of influenza like cases (ILI%) and influenza virus positive rate between 2020 and 2018-2019 were compared, so as to evaluate the impact of COVID-19 prevention and control measures on influenza epidemic characteristics. Results　The annual proportions of ILI cases in Chongqing were respectively 3.53%, 2.23% and 1.2% from 2018 to 2020, while the positive rates of influenza virus were respectively 13.97%, 23.81% and 2.65%. The distribution trend of ILI% from 2018 to 2019 fluctuated were similar, but it continued to drop and remain at a low level since February 2020. The positive rate of influenza virus showed an epidemic peak from December to March in 2018-2019, also peaked from November 2019 to January 2020, but decreased to 0 in March. ILI% was positively correlated with the positive rate of influenza virus (r=0.404 8, P<0.05). In 2020, compared with the same period of 2018-2019, the growth rate of ILI% was -66.09% and -46.32%, respectively. The positive rate of influenza virus in 2020 decreased by 81.03% and 88.87% compared with the same period of 2018-2019, respectively. The growth rates of influenza virus positive rate in January 2020 were decreased with a small rate of about 39.87%, and with a significantly decline of more than 93.65% from February. No influenza epidemic was found after March. Conclusions　Since COVID-19 prevention and control measures were implemented in January 2020 in Chongqing, the ILI% and the positive rate of influenza virus in sentinel hospitals decreased significantly. In the season of high incidence of respiratory infectious diseases, personal protection and other measures can effectively reduce influenza virus infection.

Angioplasty, Balloon, Coronary ; Coronary Thrombosis ; therapy ; Humans