Psychological effects of project-based learning in participants receiving clinical oncology teaching: A protocol of systematic review of randomized controlled trials.

BACKGROUND: This study will assess the effects of the project-based learning (PBL) for participants undergoing clinical oncology teaching (COT). METHODS: A systematic and comprehensive literature records will be identified from the electronic databases of PUBMED, EMBASE, Cochrane Library, Web of Science, Springer, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. All electronic databases will be searched from their inceptions up to the present. Any relevant randomized controlled trials on the effects of PBL in participants receiving COT will be considered for inclusion. Study quality will be assessed using the Cochrane risk of bias tool. RevMan 5.3 software will be utilized for statistical analysis. RESULTS: This study will assess the effects of PBL in participants receiving COT through assessing the primary outcomes of psychological disorders, student satisfaction, and student feedback, and secondary outcomes of examination scores, excellence rates, course examination pass rates, and clinical knowledge or skills. CONCLUSION: The findings of this study will summarize the latest evidence on the effects of PBL in participants receiving in COT. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42019150433.

[Effect of serum starvation and culture to confluence on cell cycle synchronization and mineralization of human dental pulp cells].

PURPOSE: To compare the effect of serum starvation and culture to confluence on cell cycle synchronization and mineralization of human dental pulp cells (hDPCs). METHODS: HDPCs were cultured to 80% and 100% confluence respectively, and then cultured for 24, 48 and 72 hours by culture medium containing 0.5% fetal bovine serum(FBS). Cell cycle of hDPCs were identified by flow cytometry. Then hDPCs cultured by serum starvation for 48h after culturing to 100% confluence were used as the experimental group, and hDPCs cultured to 80% confluence were used as the control group. The expression of alkaline phosphatase(ALP), collagen type Ⅰ(COL-Ⅰ) and osteocalcin(OCN) was detected at gene level; activity of ALPase was detected at protein level. SPSS 13.0 software was used for statistical analysis. RESULTS: When hDPCs were cultured by serum starvation for 48h after culturing to 100% confluence, cells at G0/G1 stage were more than culture to 100% confluence and serum starvation group (P＜0.05). At the genetic level, the expression of COL-Ⅰand OC in the experimental group was not statistically different from that of the control group, but can promote the expression of ALP(P＜0.05), and stimulate the secretion of hDPCs at protein level at the same time (P＜0.05). CONCLUSIONS: Culture to confluence combined serum starvation can synchronize more hDPCs at G0/G1 stage and promote mineralization of hDPCs.

Circadian Rhythm Regulates Development of Enamel in Mouse Mandibular First Molar.

Rhythmic incremental growth lines and the presence of melatonin receptors were discovered in tooth enamel, suggesting possible role of circadian rhythm. We therefore hypothesized that circadian rhythm may regulate enamel formation through melatonin receptors. To test this hypothesis, we examined expression of melatonin receptors (MTs) and amelogenin (AMELX), a maker of enamel formation, during tooth germ development in mouse. Using qRT-PCR and immunocytochemistry, we found that mRNA and protein levels of both MTs and AMELX in normal mandibular first molar tooth germs increased gradually after birth, peaked at 3 or 4 day postnatal, and then decreased. Expression of MTs and AMELX by immunocytochemistry was significantly delayed in neonatal mice raised in all-dark or all-light environment as well as the enamel development. Furthermore, development of tooth enamel was also delayed showing significant immature histology in those animals, especially for newborn mice raised in all daylight condition. Interestingly, disruption in circadian rhythm in pregnant mice also resulted in delayed enamel development in their babies. Treatment with melatonin receptor antagonist 4P-PDOT in pregnant mice caused underexpression of MTs and AMELX associated with long-lasting deficiency in baby enamel tissue. Electromicroscopic evidence demonstrated increased necrosis and poor enamel mineralization in ameloblasts. The above results suggest that circadian rhythm is important for normal enamel development at both pre- and postnatal stages. Melatonin receptors were partly responsible for the regulation.

RECQL1 plays an important role in the development of tongue squamous cell carcinoma.

BACKGROUND/AIMS: RECQL1, a member of the human RECQ helicase family, participates in DNA repair. Recent reports showed that RECQL1 silencing in cancer cells resulted in mitotic catastrophe, which prevented tumor growth in murine models. However, its therapeutic potential has never been examined in tongue squamous cell carcinoma (SCC). METHODS: To explore the role of RECQL1 in the development of tongue SCC, we used RNA interference technology to silence RECQL1 in SCC-9 and SCC-15 human tongue SCC cell lines, and to subsequently evaluate its effects both in vitro and in vivo. RESULTS: After RECQL1 was silenced in SCC cells by siRNA, we observed downregulation of RECQL1 mRNA and protein in cancer cells. RECQL1 is one of the predicted miR-203 targets, and we found that miR-203 downregulated the expression of RECQL1 at the post-transcriptional level. RECQL1-shRNA or miR-203 overexpression inhibited SCC-9 cell growth. In addition, there was accumulation of cells in the sub-G1 fraction and increased apoptosis 72 h post-transfection. In addition, knockdown of RECQL1 led to a strong anticancer effect, as the tumorigenicity of SCC-9 cells was inhibited in vivo. Moreover, we found that two immunosuppressive factors were also significantly downregulated upon RECQL1 knockdown or miR-203 overexpression in vitro. CONCLUSION: Collectively, these results indicate that RECQL1 plays an important regulatory role in cancer cell proliferation and tumor progression.

Trichome-specific expression of the amorpha-4,11-diene 12-hydroxylase (cyp71av1) gene, encoding a key enzyme of artemisinin biosynthesis in Artemisia annua, as reported by a promoter-GUS fusion.

Artemisinin derivatives are effective anti-malarial drugs. In order to design transgenic plants of Artemisia annua with enhanced biosynthesis of artemisinin, we are studying the promoters of genes encoding enzymes involved in artemisinin biosynthesis. A 1,151 bp promoter region of the cyp71av1 gene, encoding amorpha-4,11-diene 12-hydroxylase, was cloned. Alignment of the cloned promoter and other cyp71av1 promoter sequences indicated that the cyp71av1 promoter may be different in different A. annua varieties. Comparison to the promoter of amorpha-4,11-diene synthase gene showed a number of putative cis-acting regulatory elements in common, suggesting a co-regulation of the two genes. The cyp71av1 promoter sequence was fused to the ß-glucuronidase (GUS) reporter gene and two varieties of A. annua and Nicotiana tabacum were transformed. In A. annua, GUS expression was exclusively localized to glandular secretory trichomes (GSTs) of leaf primordia and top expanded leaves. In older leaves, there is a shift of expression to T-shaped trichomes (TSTs). Only TSTs showed GUS staining in lower leaves and there is no GUS staining in old leaves. GUS expression in flower buds was specifically localized to GSTs. The recombinant promoter carries the cis-acting regulatory elements required for GST-specific expression. The cyp71av1 promoter shows activity in young tissues. The recombinant promoter was up to 200 times more active than the wild type promoter. GUS expression in transgenic N. tabacum was localized to glandular heads. Transcript levels were up-regulated by MeJA. Wound responsiveness experiment showed that the cyp71av1 promoter does not appear to play any role in the response of A. annua to mechanical stress.

BAFF induces spleen CD4+ T cell proliferation by down-regulating phosphorylation of FOXO3A and activates cyclin D2 and D3 expression.

The TNF ligand family member "B cell-activating factor belonging to the TNF family" (BAFF, also called BLyS, TALL-1, zTNF-4, and THANK) is an important survival factor for B and T cells. In this study, we show that BAFF is able to induce CD4(+) spleen T cell proliferation when co-stimulated with anti-CD3. Expression of phosphorylated FOXO3A was notably down-regulated and cyclins D2 and D3 were up-regulated and higher in the CD4(+) T cells when treated with BAFF and anti-CD3, as assessed by Western blotting. Furthermore, after FOXO3A was knocked down, expression of cyclin D1 was unchanged, compared with control group levels, but the expression of cyclins D2 and D3 increased, compared with the control group. In conclusion, our results suggest that BAFF induced CD4(+) spleen T cell proliferation by down-regulating the phosphorylation of FOXO3A and then activating cyclin D2 and D3 expression, leading to CD4(+) T cell proliferation.

[Evaluation of X-ray beam angulation for successful four canals identification in the mandibular first molars].

PURPOSE: This study was aimed to determine the most effective horizontal beam angulation to identify 4 canals in the mandibular first molars, so as to provide full and accurate information for the clinic. METHODS: One hundred and twenty mandibular first molars with four canals that needed endodontic treatment in vivo were selected. Radiographs were taken at horizontal angles of 0,10,20 degrees from distal direction and 0,10,20,30 degrees from mesial direction of the tooth. The numbers of root canal and the degree of resolution were identified and recorded by 3 independent observers. Data were analyzed using SPSS10.0 software package or Chi-square test. RESULTS: At 30 and 20 degrees from mesial direction, 93.3% and 90.0% of all the 120 teeth were correctly identified as 4 canals, compared with 0 degree of 40.0%(P<0.01). Of them, 71.5% and 89.7% could be classified as with high resolution, respectively. The latter was not significantly lower than 0 degree of 95.0% (P>0.05). CONCLUSION: Twenty degrees from mesial direction is the most effective X-ray beam angle in diagnosing 4 canals of the first mandibular molars. Supported by Research Fund of Science and Technology Commission of Shanghai Municipality (Grant No.08DZ2271100).

[Clinical effect of three kinds of rotary nickel-titanium instruments on root canal preparation of molars].

PURPOSE: To evaluate three kinds of nickel-titanium instruments applied to molar root canal preparation. METHODS: A total of 90 molars treated by root canal therapy were randomly assigned to three groups: ProTaper group. K3 group and Mtwo group. Crown-down technique was used in ProTaper and K3 group, while Mtwo group was treated with routine preparation technique. All teeth in 3 groups were filled by lateral condensation technique. Treatment effect of 3 groups was evaluated according to pre- and post-operative X-ray films. Wearing and tearing degree of equipment, preparation time and postoperative complications incidence of 3 groups were also compared. All statistical analysis was performed using SAS9.0 software package. Data of root canal curvatures and preparation time was compared using t test; the incidence of complications of root canal treatment and postoperative pain was analyzed using Chi-square test. RESULTS: In three groups, root canals had no deviation or no ledge, could maintain the root canal anatomy in early form, and achieved good preparation results. In this study, four ProTapers, three K3s and one Mtwo instrument were fractured. The average root canal preparation time of the Mtwo group was 3.94 min, significantly less than the ProTaper (4.71 min) group and the K3(4.58 min) group. CONCLUSIONS: Three rotary nickel-titanium systems tested in this study are effective in the molar root canal preparation. The Mtwo instrument is much easier and faster during preparation with routine preparation technique.Supported by Research Fund of Science and Technology Commission of Shanghai Municipality(Grant No.08DZ2271100).

[Construction and prokaryotic expression of recombinant gene EGFRvIII HBcAg and immunogenicity analysis of the fusion protein].

AIM: To construct recombinant prokaryotic expression plasmid pET28a(+)/c-PEP-3-c and evaluate the immunogenicity of the fusion protein. METHODS: cDNA fragment encoding PEP-3 was obtained from pGEM-T Easy/PEP-3 and inserted into recombinant plasmid pGEMEX/HBcAg. Then it was subcloned in prokaryotic expression vector and transformed into E.coli BL21(DE3). The fusion protein was expressed by inducing IPTG and purified by Ni(2+)-NTA affinity chromatography. BALB/c mice were immunized with fusion protein and the antibody titre was determined by indirect ELISA. RESULTS: The recombinant gene was confirmed to be correct by restriction enzyme digestion and DNA sequencing. After prokaryotic expression, fusion protein existed in sediment and accounted for 56% of all bacterial lysate. The purified product accounted for 92% of all protein and its concentration was 8 g/L. The antibody titre in blood serum reached 1:16 000 after the fourth immunization and reached 1:2.56x10(5) after the sixth immunization. The titre of anti-PEP-3 antibody reached 1:1.28x10(5) and the titre of anti-HBcAg antibody was less than 1:4x10(3). CONCLUSION: Fusion gene PEP-3-HBcAg is highly expressed in E.coli BL21. The expressed fusion protein can induce neutralizing antibody with high titer and specificity, which lays a foundation for the study of genetically engineering vaccine for malignant tumors with the high expression of EGFRvIII.