Most academic information appears in the database and academic websites;in rencent years the blog and podcast also transmit academic information.Medical graduates need to check new information regularly after busy routine work,but how to effectively collect and manage academic information is a problem.This paper describes the new strategies and methods for them to use.

BACKGROUND: Growth differentiation factor-5 (GDF-5) plays an important role in the development and formation of cartilage, extremities, and joints, which is a widely used joint development marker.OBJECTIVE: To express mature peptide of human GDF-5 in E. coil by the way of genetic engineering, and to explore the inductive activity of recombinant protein in vivo.DESIGN, TIME AND SETTING: The observation experiment based on gene was performed at the Analysis and Testing Center of Southern Medical University from January to June 2006.MATERIALS: Human fetus cartilage tissue was harvested from Department of Gynaecology and Obstetrics, and the consent was obtained from the family. Ten KM mice were purchased from experimental animal center of Southern Medical University, half male and half female, weighing 18-22 g, aged 6-8 weeks.METHODS: The hGDF-5 gene encoding mature peptide was gained by RT-PCR from the total RNA which was extracted from fetus cartilage tissues, and was inserted into the pET22b(+) vector to construct recombinant prokaryotic expression plasmid pET22b(+)-GDF5, which was transformed into E. coil BL-21 to be expressed after IPTG induction. Proteins of interest were purified with sepharose chelated with nickel ions (Ni2+) and then implanted in mouse hindlimb muscle to evaluate the biological activities by routine hematoxylin-eosin staining.MAIN OUTCOME MEASURES: The expression, sequencing of target gene was observed by agarose gel electrophoresis, and the protein expression was detected by SDS-PAGE electrophoresis, meanwhile, the GDF5-inducing activity was evaluate by histological observation.RESULTS: RT-PCR product was about 350 bp in length, which was confirmed by double enzyme digestion of the recombinant plasmid, sequencing result was in agreement with the reported hGDF-5 sequence in Genbank. SDS-PAGE analysis showed a conspicuous band representing a new foreign protein with relative molecular mass of approximately 14 KD after induced expressioin. Cartilage tissues were formed in the mouse muscle where the purified proteins were implanted. CONCLUSION: The integral human GDF-5 mature peptide gene was cloned successfully from human fetus cartilage tissue and a high-yield expression was achieved in E. coli, the pudfied protein has chondrogenic activities in vivo.

Chemotherapy is the preferred therapeutic approach for advanced ovarian cancer, but a successful long-term treatment is prevented by the development of drug resistance. Recent works have underlined the involvement of non-coding RNAs, microRNAs (miRNAs) in cancer development, with several conjectures regarding their possible involvement in the evolution of drug resistance. This study is to investigate the promoting effects and mechanism of miR-125b involved in the development of chemoresistance in ovarian cancer. The different expression of miR-125b in cisplatin-sensitive ovarian cancer cell line (OV2008) and its resistant variant (C13*) was identified by real-time PCR. An in vitro cytotoxicity assay and apoptosis assay using CCK-8 assay and flow cytometry, were carried out to detect the effect of miR-125b and Bak1 on cisplatin resistance of cells. Real-time PCR, Western blotting and luciferase reporter assay were used to detect whether Bak1 is a target of miR-125b. As compared with OV2008 cells, the expression levels of miR-125b in C13* cells were increased. It was found that the up-regulation of microRNA-125b caused a marked inhibition of cisplatin-induced cytotoxicity and apoptosis and a subsequent increase in the resistance to cisplatin in OV2008 and C13* cells. Moreover, Bak1 was a direct target of miR-125b, and down-regulation of Bak1 suppressed cisplatin-induced apoptosis and led to an increased resistance to cisplatin. Our study indicates that miR-125b has a significantly promoting effect on chemoresistance of C13* cells and up-regulation of miR-125b expression contributes to cisplatin resistance through suppression of Bak1 expression. This finding has important implications in the development of targeted therapeutics for overcoming cisplatin resistance in ovarian cancer.

Objective To investigate the metabolite changes in systemic lupus erythematosus (SLE) patients with and without neuropsychiatric symptoms using magnetic resonance spectroscopy (MRS) and explore the associations between image findings and clinical variables. Methods Twenty-two SLE patients with neuropsychiatric symptoms (NPSLE), twenty-one SLE patients without neuropsychiatric symptoms (non-NPSLE) and twenty healthy controls (HCs) underwent routine MRI scan and multivoxel magnetic reson-ance spectroscopy (MVS). The absolute metabolite concentrations were measured bilaterally in the posterior cingulate gyrus (PCG), dorsal thalamus (DT), lentiform nucleus (LN) and posterior paratrigonal white matter (PWM) using LCModel and SAGE software. The relationships between metabolite con-centrations and cognitive function scores were analyzed by Spearman rank correlation. Single-factor Chi-square analysis and t-test were used for analysis. Results ① Compared to control subjects, NPSLE patients had significantly lower N-acetylaspartate (NAA) values in bilateral PCG and DT, with the mean differences of -1.504 [95% confidence interval ( CI) (-2.335, -0.672), P=0.001], -1.460 [95%CI (-2.349, -0.570), P=0.002], -1.259 [95%CI (-1.894, -0.625), P=0.000] and -1.022[95%CI (-1.688, -0.356), P=0.003] for RPCG, LPCG, RDT and LDT, respectively. The concentration of total creatinine were observed to decline in RPCG and RDT, with the mean differences of-1.094 [95%CI (-1.845, -0.342), P=0.003], -0.955 [95%CI (-1.630, -0.280), P=0.006], -1.259 [95%CI (-1.894,-0.625), P=0.006] respectively. Glutamine and glutamate-values decreased significantly in RDT [mean difference=-2.586, 95%CI (-4.139, -1.033), P=0.002]. ② Compared to non-NPSLE patients, NPSLE patients had a lower NAA level in LPCG [mean difference=-1.256, 95%CI (-2.146, -0.367), P=0.006]. Positive correlations between mini-mental state examination scores [RPCG: rs=0.312, P<0.05; LPCG: rs=0.355, P<0.01], Montreal cognitive assessment scores (RPCG: rs=0.362, P<0.01; LPCG: rs=0.285, P<0.05) and NAA values in bilateral PCG were detected. Conclusion Both NPSLE and non-NPSLE patients may have metabolite dysfun-ctions in different brain regions. The cognitive disorder in SLE patients may be interpreted by neuronic damage of PCG.

Objective To investigate the effects of gene transfection with human growth/differentiation factor 5(GDF5)on the growth and difierentiation of bone nlarrow stromal stem cells (BMSCs).Methods GDF5 gene was trans fected into BMSCs by liposome method. Then cell proliferation and cycles were examined by MTT and flow cytometry respectively. Cell morphology was observed under light microscope and electron microscope (EM).GDF5 and Collagen Ⅱ were detected at the level of mRNA and protein by RT-PCR and immunocytochemistry. Alkaline phosphate activity was examined by lead citrate method. Osteocalcin mRNA expression was determined bv RT-PCR. ResulIs GDF5 gene was transfected into BMSCs successfully and the transfected cells still maintained their natural growth and proliferation features. Stable expression of GDF5 gene in BMSCs was obtained. The trans fected ceils had basically the same proliferation ability and cell cycles as the untransfccted ones. After transfection comparatively more polygonal cells could be seen in light microscope, showing irregular arrangement mode. Plenty organells were observed and cell nucleus showed irregular shape under EM. The expressions of Collagen Ⅱ mRNA and protein were positive. But osteocalcin mRNA expression was negative. Conclusion Since BMSCs can be induced by GDF5 to differentiate into chondrogenic cells. GDF5 gene-modified BMSCs may be used as candidate seed cells of cartilage tissue engineering.

The integral mature peptide gene of human growth differentiation factor-5 (GDF-5) was cloned to provide the essential foundation for study on the biological characteristics of GDF-5 at gene and protein levels. Two primers were chemosynthesized according to the hGDF-5 sequence reported in Genbank. The hGDF-5 gene was gained by RT-PCR methods from the total RNA extracted from human fetus cartilage tissue, and was cloned into vector pMD18-T. The sequence of recombinant plasmid pMD18-T-hGDF-5 was analyzed by sequence analysis. DNA agarose gel electrophoresis showed that the product of RT-PCR was about 380bp, and double enzyme digestion of the recombinant plasmid corresponded with it. The result of sequence assay was in agreement with the reported hGDF-5 sequence in Genbank. Our results showed that the integral mature peptide gene of human GDF-5 was cloned successfully from human fetal cartilage tissue, and totally identified with the sequence of human GDF-5 in Genbank.
Bone Morphogenetic Proteins ; biosynthesis ; genetics ; Cartilage ; chemistry ; Cloning, Molecular ; Fetus ; Genetic Vectors ; Growth Differentiation Factor 5 ; Humans ; Transforming Growth Factor beta ; biosynthesis ; genetics

Objective To study the application value of laparoscopic curettage in the standardized training for residents.Methods In this study,we selected residents of the Wuhan First Hospital as the research subjects.Thirty of the subjects from the 2015 grade were the control group and another 29 from the 2016 grade were the experimental group.Both groups had three classes,including one theory class,and two practice classes.After the theoretical class,the experimental group practiced laparoscopic curettage,while the control group practiced curettage.After practice,the experimental group filled out the questionnaire on teaching quality,and both groups participated in the theory test.Results Laparoscopic curettage can significantly improve students' ability to learn and understand curettage,so that most students can adapt to curettage,eliminate the panic from uterine perforation and be more sensitive to the uterus textures,and satisfactory teaching results were achieved.The average score of the practice test for the experimental group (9.150 ± 2.461) was statistically higher than that for the control group (7.053 ± 1.347).The average score of the theory test (7.581 ± 1.632) for the experimental group was not statistically different from that for the control group (6.983 ± 1.726).The average scores of the two tests for the experimental group (9.037 ± 1.951) and the control group (6.891 ± 2.140) were statistically different.Conclusions Laparoscopic curettage can significantly improve the ability to learn,understand and feel curettage for residents who are under standardized training,and it has great application value in the three basic operation trainings.

Objective:To construct the selection index system of clinical nursing teachers, and to provide theoretical basis for improving the comprehensive quality of clinical teachers and the comprehensive clinical practice ability of undergraduate nursing students.Methods:Using the methods of literature review, brainstorming and semi-structured interview, the selection index system of clinical nursing teachers was initially constructed. Delphi method was used to conduct two rounds of consultation on 25 experts. SPSS 20.0 was used to analyze the consulting data and calculate the experts' positive coefficient, authority coefficient, degree of concentration of opinions and degree of coordination, and the index contents were modified and improved according to the expert opinions. Finally, the selection index system of clinical nursing teachers was established.Results:Based on the two rounds of expert consultation, the positive coefficient of experts was 96%, the authoritative coefficient of experts was 0.857 and 0.848 respectively, and the coordination coefficient of experts was 0.277~0.442 ( P<0.001). Four first level indexes, 12 second level indexes and 45 third level indexes were determined. Conclusion:The selection index system of clinical nursing teachers is scientific and reliable, which can provide a theoretical basis for the selection of clinical nursing teachers.

Objective:To explore the application effect of TBL (team-based learning) + PAL (peer assisted leaning) + Flipped Class mixed teaching mode in the course of "nursing psychology" for nursing undergraduates.Methods:A total of 146 nursing undergraduates from four classes enrolled in 2018 were subjected to cluster sampling and assigned to classes 1-2 (experimental group, n=73) and classes 3-4 (control group, n=73). The experimental group adopted the TBL + PAL + Flipped Class mixed teaching mode, while the control group adopted the traditional teaching method. After the course, the two groups were evaluated by final exam score, case analysis score, and core competence self-assessed score with a t-test in SPSS 18.0. Results:The final examination score (82.30±7.77) and case analysis score (46.13±2.91) of the experimental group were significantly higher than those in the control group (74.97±7.05 and 40.36±4.25). The experimental group showed significantly higher scores in autonomous learning ability (8.03±0.91), problem analysis ability (7.99±0.99), teamwork ability (7.67±1.09) and critical thinking ability (7.03±1.33) as compared with the control group (6.21±1.17, 5.64±1.28, 5.79±1.27, 5.15±1.16).Conclusion:TBL + PAL + Flipped Class mixed teaching mode integrates the advantages of the three teaching forms, promotes students' understanding and application of knowledge points, improves students' ability of independent learning, teamwork, and problem analysis, strengthens students' ability of transfer and application of knowledge and skills, increases the teaching effect, and expands the teaching method of nursing psychology.

Objective:To investigate the distribution characteristics of bacteria in urine of patients with ureteral stent crusting.Methods:Thirty-five patients who underwent ureteral stent placement at the Shandong Provincial Third Hospital, Shandong University Qilu Hospital, Jinan Central Hospital, and Jinan Jigang Hospital were selected from October, 2018 to March, 2019(the clinical study registration number is ChiCTR1800020025). The inclusion criteria were patients who had the stent intubated for 4 weeks after ureteroscopic lithotripsy, aged between 18 and 65 years. Exclusion criteria were patients with positive urine bacterial culture, severe gross hematuria, recent oral antibiotics, and patients with significant residual stones. This clinical study uses a cross-sectional study method, and those patients were divided into crusting group (n=23) and non-crusting group (n=12) according to the presence or absence of stent crusting. On the day of extubation, urine of the patients was collected for bacterial 16s DNA detection. The distribution characteristics of bacteria in urine of the two groups were analyzed using UPARSE, UCHIME and RDP calssifier. The total number of bacteria species, bacterial abundance and bacterial species with large-scale abundance in urine of the two groups were determined. The quantity of bacteria species and bacterial abundance in the urine between the two groups were compared, and the bacterial species with large-scale abundance in urine of the patients with stent crusting were identified.Results:There were no significant differences in general information such as age, body mass index, gender, affected side, type of stent tube, and stone composition between the two groups. Using 16s DNA sequencing to detect the bacteria in the urine of the two groups revealed that the number of bacterial species with abundance >1% was 11, and the number of bacterial species with abundance >0.01% was 74 in the crusting group. In the non-crusting group, the number of bacterial species with abundance >1% and >0.01% was 7 and 11, respectively. Compared with the non-crusting group, the number of bacterial species with abundance >1% in the crusting group was significantly larger ( t=5.12, P=0.000). In the crusting group, bacterial species with the top three abundance were g_Lactobacillus (23.1%), g_Bacteroides (18.8%) and g_norank_Bacteroides (17.1%). In the non-crusting group, bacterial species with the top three abundance were g_Escherichia-Shigella (32.2%), g_Enterococcus (24.9%) and g_Pseudomonas (18.2%). The three bacteria with the greatest difference between the two groups were g_ Lactobacillus ( P=0.010), g_Bacteroides ( P=0.004) and g_norank_Bacteroides ( P=0.004), respectively. Conclusion:The species and quantity of bacteria in the urine of patients with stent crusting are both significantly larger than those of patients without stent crusting. Bacteroides with larger-scale abundance in the urine of patients with stent crusting may promote the deposition of crystals on the stent wall through its structure, function and urease positive characteristics.