Objective To study the profiles and function of small RNA (sRNA)gene during chondrogenesis in rats so as to clarify the mechanisms of chondrocytes proliferation and differentiation.Methods All the sRNAs were identified from the female SD rats femoral head cartilages at three time points:at birth,ablactation and maturation,and three sRNA libraries were constructed.The Solexa sequencing and the bioinformatics analysis were employed to be blasted with the genomes of SD rats.Results The perfect match reads in the three libraries were screened out,which were correspondent to the 21 7 921 (41.23%),1 96 650 (38.74%)and 245 436 (41.54%)unique sRNA sequence,respectively.The percentages of 20-24 nt sRNA were 71.94% (d0),72.85% (d21),and 86.39%(d42).Half of clean sequences were 22 nt sRNA.The distribution characteristics of the reads were in line with the high-quality sRNA.More than 62% clean reads were from mature miRNA while the ratios in the three libraries were only 0.69%,0.78% and 0.63%.About 60% of the unique sRNA could not be matched with miRBase20.0 or Rfam9.1.Conclusion The distribution model of miRNA in the three libraries indicates that the miRNAs with different functions or from different sources are involved in the regulation of chondrocytes proliferation and differentiation in bone development and formation.

OBJECTIVE To investigate the transgenerational effect of neuroendocrine metabolic programmed alteration in adult intrauterine growth retardation (lUGR) offspring rats with prenatal nicotine exposure. METHODS Pregnant Wistar rats were administered daily with nicotine (2 mg.kg-1 ) by sc from gestational day 11 until delivery. F1 offspring was fed with a standard diet before four groups in F2 were set up according to the cross-mating between F1 normal adult rats and nicotine-induced lUGR adult rats. CC group was mated by F1 normal adult rats, CN group by F1 normal adult male rats and lUGR adult female rats, NC group by F1 lUGR adult male rats and normal adult female rats, while NN group was mated by F1 lUGR adult rats. F2 adult rats were subjected to a fortnight ice water swimming stimulus. Blood samples were collected before and after stress and then detected for the levels of adrenocortico-tropic hormone ( ACTH), corticosterone ( CORT), glucose, triglycerides ( TG) and total cholesterol (TCH). RESULTS Before stress, the level of serum CORT in F2 male rats of NN group was decreased to 73.9% of that of the CC group (P<0.05),while the level of serum TG in F2 male rats of CN and NC groups was increased to 1.43 and 1.52 times that of the CC group, respectively ( P<0.05). Meanwhile, the level of serum TG in F2 female rats of CN, NC and NN groups was increased to 1.71, 1.80 and 1.81 times that of the CC group, respectively (P<0.05). After stress, the serum CORT gain rate in F2 male rats of CC group was -1.67%, but was 36.0% in NN group. The serum glucose level in male NC group and in female CN group was increased to 1.61 and 1.62 times that of the corresponded CC groups, respectively (P<0.01). Furthermore, the serum TG gain rate in F2 rats of each nicotine group was decreased markedly in comparison with their corresponding controls (P<0.05), ie, the serum TG gain rates in F2 male rats of CN, NC and NN groups were decreased to 46.4%, 16.7% and 7.7% of the CC group, while the serum TG gain rates in F2 female rats of these groups were decreased to 20.6%, 4.0% and 8.4% of the CC group, respectively. Compared with CC group, TCH level of females and males in NN group was decreased by 40.5% and 21.9%(P<0.01) before stress, respectively, and the TCH gain rate of females in NN group was increased by 49.7%(P<0.05) after stress. CONCLUSION The reproductive and developmental toxicities and the neuroendocrine metabolic programming alterations induced by prenatal nicotine exposure are transgenerated to F2 offspring and these effects exhibit gender and parental differences.

Objective To evaluate the stability of U6 and let-7a as internal reference genes of miRNAs in RTqPCR by using femoral head samples of cartilage tissue from inbred DA rats.Methods Total RNA was extracted from femoral head cartilage tissues of female DA rats at three different time points,i.e.at birth (D0),ablactation (D21) and maturation (D42).The expressions of different miRNAs (miR-1,-25,-26a,-140,-146a,-150,-181a,-195,-223 and-337) were detected by RT-qPCR using U6 or let-7a as the internal reference.The two sets of miR expression were compared with the results from Solexa sequencing in our pioneer work to evaluate the stability of the two internal references.Results The relative values of U6 (P =0.045) and let-7a (P =0.021 5) revealed significant difference in the D42 sample.Both in U6 and let-7a systems,miR-26a,-140,-223,and-337 showed a similar tendency in expression and quantification but miR-1 and-146a did not have significant differences.miR-25,-150,-181a and-195 differed significantly (P＜0.05).Comparison of absolute quantification results between the two generations' sequencing showed that let-7a is more stable than U6.Conclusion Let-7a is more suitable to be used as the internal reference gene in RT-qPCR for miRNAs in cartilage tissue.

Objective To investigate the relationship between DNA topoisomerase Ⅱ α (TOP2A) gene expression and clinicopathological characteristics and its significance of prognostic evaluation for patients with bladder cancer.Methods Bladder cancer gene expression profile GSE13507 (n =165) and GSE31189 (n =52) were obtained.The expression profile and clinical information of patients with bladder cancer were retrospectively analyzed,and the survival analysis was made.Gene set enrichment analysis (GSEA) was conducted to explore the related pathways which were regulated by TOP2A.Results Compared with normal bladder tissues,TOP2A was upregnlated in bladder cancer tissues (5.823 ± 1.079 vs.4.820 ± 1.129),with a statistically significant difference (t =4.336,P ＜ 0.001).The TOP2A gene expression in patients with bladder cancer was correlated with the age of patients (x2 =5.926,P =0.015),sex (x2 =6.046,P =0.014),T staging (x2 =19.484,P ＜ 0.001),N staging (x2 =9.178,P =0.002),M staging (x2 =21.142,P ＜ 0.001),tumor grade (x2 =47.005,P ＜ 0.001),and progression (x2 =11.735,P =0.001),but it was not correlated with recurrence (x2 =0.808,P =0.369).Survival analysis showed that the specific survival rate in the 100 months of TOP2A gene high expression group and low expression group had a statistically significant difference (66.59％ vs.87.95％,x2 =15.820,P ＜ 0.001).The median overall survival time of TOP2A gene high expression group and low expression group were 51.77 months and 134.97 months respectively,with a statistically significant difference (x2 =11.280,P =0.008).The results of GSEA indicated that TOP2A could regulate gene sets related with several pathways like MYC-V1 signaling (P =0.035,FDR =0.132),MYC-V2 signaling (P =0.012,FDR =0.058),E2F signaling (P ＜ 0.001,FDR =0.006) and G2M checkpoint (P =0.006,FDR =0.044).Conclusion The TOP2A gene expression is closely related with clinicopathological characteristics of patients with bladder cancer.TOP2A may function as a potential marker of prognosis for patients with bladder cancer.

Objective To investigate the effects of morroniside on the expression of vascular endothelial growth factor (VEGF) and fi-broblast growth factor-2 (FGF-2) in rat cortex after focal cerebral ischemia-reperfusion. Methods 30 male Sprague-Dawley rats were ran-domly divided into sham group, model group, morroniside-low group (30 mg/kg), morroniside-middle group (90 mg/kg) and morroni-side-high group (270 mg/kg). Middle cerebral arteries of rats were occluded for 30 minutes with Longa's method and re-perfused. The ex-pression of VEGF and FGF-2 in the ischemic ipsilateral cortex was detected with Western blotting 7 days after reperfusion. Results The ex-pression of both VEGF and FGF-2 increased in the ischemic ipsilateral cortexin in all the ischemic groups compared with the sham group (P<0.05). The expression of VEGF further increased in a dose-dependent manner in all the morroniside groups compared with that of model group (P<0.05), and the expression of FGF-2 increased in the morroniside-high group (P<0.001). Conclusion Morroniside could increase the expression of VEGF and FGF-2 after ischemia-reperfusion, which might promote angiogenesis.

Objective To explore the effects of morroniside on the expression of CD34 in ipsilateral cortex of rats after focal cerebral isch-emia-reperfusion. Methods 45 male Sprague-Dawley rats were divided into sham group (n=9), ischemia group (n=9), and morroniside groups (low, medium and high dosage groups, n=9). The middle cerebral artery were occluded for 30 minutes, and reperfused. Morroniside was administered intragastrically once a day at dose of 30 mg/kg, 90 mg/kg, 270 mg/kg after operation. The expression of CD34 in the isch-emic ipsilateral cortex were detected with immunohistochemistry (n=6) and Western blotting (n=3) 7 days after operation. Results The ex-pression of CD34 increased in the ischemia group compared with the sham group, and further increased in the morroniside groups of high dos-age compared with the ischemia group (F>14.865, P<0.001). Conclusion Morroniside could increase the expression of CD34 in the ischemic ipsilateral cortex after ischemia-reperfusion in rats, which may promote the angiogenesis and neurogenesis after ischemia.

Objective:To investigate the cognition and willingness of nursing staff to Internet plus nursing service, and analyze the related factors that affect their participation in Internet plus nursing service.Methods:From April to May 2019, 150 nurses from three hospitals in Weifang were investigated by questionnaire and key person interview. Descriptive analysis and binary logistic regression analysis were used to analyze the intention of nursing staff to participate in Internet plus nursing service. The interview mode was used to analyze the appropriate mode of Internet plus nursing service from the perspective of nursing staff.Results:142 valid questionnaires were obtained, of which 137(96.5%)indicated willingness to provide Internet plus nursing services, and 135(95.1%) realized the necessity of the service. Education, marriage, nurses′judgment on the necessity of the service and their own subjective judgment of their competence were the factors affecting nurses′ participation in the Internet plus nursing service.Conclusions:Multiple factors affect the choice of nursing staff′s behavior in Internet plus nursing service.From the perspective of nursing staff, the Internet plus nursing service mode needs joint efforts from many aspects.

Objective:To evaluate and analyze the patient experience of residents contracted with primary medical institutions, for providing a basis for improving quality of contracted family doctor services.Methods:Using the Chinese version of the primary care assessment tools(PCAT), a household survey was conducted on 1 400 contracted residents in 9 community health service centers and 9 township health centers in a city from May to June 2020, and their medical experience in primary medical institutions was statistically analyzed. At the same time, interviews were conducted with institutional managers and family doctors. Descriptive statistics and one-way ANOVA were used for data analysis.Results:1 333 valid questionnaires were collected, and the effective recovery rate was 95.2%.The total PCAT scoring was 25.17. Seven dimensions of first contact, continuous, coordination, comprehensiveness, patient and family centered, community-oriented and cultural competence scored in average 3.57, 3.68, 3.54, 3.40, 3.72, 3.67 and 3.59 respectively.372 people(47.1%) had not been referred by the contracted institution before going to the superior hospital or specialized hospital. There were significant differences in the scores of four core dimensions in different types of institutions, age, education level, occupation and income( P<0.001). Conclusions:Given the initial progress of contracted family doctor services in the city, there is still room for improvement. It is suggested to further improve the comprehensiveness, coordinationand accessibility of services, and promote the high-quality development of contracted family doctor services.

Objective:To investigate the role of serum hepatitis B virus RNA (HBV RNA) in predicting HBeAg serological conversion in children with chronic hepatitis B.Methods:175 children aged 1~17 years with chronic hepatitis B who received interferon α (IFNα) for 48 weeks were selected. Patients were divided into HBeAg seroconversion and non-conversion based on whether HBeAg seroconversion occurred at 48 weeks of treatment.T-test and Mann-Whitney U test were used to compare between groups; chisquare test or Fisher exact probability method was used to compare the frequency between groups of classified variables; and Pearson correlation was used to analyze the correlation between indicators. Univariate and multivariate logistic regression analyses were used to identify influencing factors associated with HBeAg serological conversion. The predictive effect of HBV RNA, HBV DNA, and HBsAg on HBeAg serological conversion was compared and analyzed by the receiver operating characteristic curve (ROC).Results:The seroconversion rate of HBeAg at 48 weeks was 36.0% (63/175). The reduction in HBVRNA levels from baseline to the 12th, 24th, 36th, and 48th weeks of antiviral therapy was significantly greater in the HBeAg serological conversion group than that in the non-conversion group, and the difference was statistically significant between the two groups (P < 0.05). Univariate and multivariate regression analyses showed that age and a decline in HBV RNA levels at week 12 were independent predictors of HBeAg serological conversion. The area under the ROC curve (AUROC) of HBV RNA decline at week 12 was 0.677(95% CI∶0.549-0.806, P = 0.012), which was significantly better than the same period of AUROC of HBV DNA (0.657, 95% CI∶0.527-0.788, P = 0.025) and HBsAg (0.660, 95% CI∶0.526-0.795, P = 0.023) decline. HBV RNA levels decreased (>1.385 log10 copies/ml) at week 12, with a positive predictive value of 53.2%, a negative predictive value of 72.2%, a sensitivity of 77.4%, and a specificity of 57.9% for HBeAg seroconversion. Conclusion:HBV RNA level lowering during the 12th week of antiviral therapy can serve as an early predictor marker for HBeAg serological conversion in children with chronic hepatitis B.

Objective To systematically analyze the relevant literatures of problem-based learning (PBL) and to provide reference for further improvement and innovation. Methods Using bibliometric method and the package "tm" in R, we searched web of science database for PBL relevant literatures from inception to March 19 of 2018. Results A total of 5710 articles published in 77 journals had been collected. The results showed that PBL relevant literatures were increasing from 1976 to 2018. Most papers were published as article, with first authors from 84 countries of the world. The total citation of 5710 articles is 54768 and the average referenced times is 9.59. The research in those articles focused on medical education, health care sciences and engineering. Conclusions PBL has been widely used in various disciplines, especially in medical education. The research involves a wide range but the quality and depth of the study is still need to be improved.