Research progress on aspiration in patients with dysphagia after ischemic stroke / 中国基层医药

Based on the research results of aspiration in patients with dysphagia after ischemic stroke at home and abroad, this paper reviews the definition, detection methods, and risk factors of aspiration and emphasizes the incidence rate and severity of this disease. The authors conclude that preventing aspiration can decrease the incidence rate of aspiration pneumonia, change the clinical outcome of patients, and thereby save medical resources.

Application of digital 3D printed model combined with case-based learning in practice teaching of oral and maxillofacial surgery / 中华医学教育探索杂志

Objective:To investigate the application effect of the combined teaching model of digital 3D printed model and Tencent conference in case-based learning (CBL) teaching of oral and maxillofacial surgery.Methods:A total of 80 undergraduates in the classes of 2015 and 2016 were selected from School of Stomatology, Qingdao University. The students in the class of 2015 received traditional teaching, and those in the class of 2016 received the combined CBL teaching model of 3D printed model and Tencent conference. A questionnaire survey was used to evaluate the teaching effect, and theoretical examination was used to assess comprehensive abilities of the two groups. SPSS 24.0 was used to perform the chi-square test and the t-test. Results:There was no significant difference in the degree of satisfaction with teaching between the combined CBL teaching model of 3D printed model and Tencent conference and the traditional teaching model ( P>0.05), and both models were generally recognized and accepted by students. The experimental group had a significantly higher score than the control group (94.05±4.16 vs. 86.10±3.37, P<0.05). Conclusion:The combined teaching model of digital 3D printed model and Tencent conference integrates the advantages of the Internet and digital information and thus provides a certain reference for the teaching methods for other majors in stomatology.

[The role of extracellular signal regulated kinase 1/2 in mediating osteodifferentiation of human periodontal ligament cells induced by cyclic stretch].

OBJECTIVE: This study aimed to investigate the mechanism of cyclic stretch that promotesthe osteogenic differentiation of human periodontal ligament cells (hPDLCs) through the mediation of extracellular-signal-regulated kinase 1/2 (ERK1/2). METHODS: hPDLCs were isolated through the explant method and cultured in vitro. hPDLCs were mechanically stimulated by a multi-channel cell-stress-loading system for 1, 3, 6, 12, and 24 h. The magnitude of stretch was 10% deformation, and the frequency was 0.5 Hz. Nonloaded cells were used as control group. ERK1/2 activation was blocked by U0126, a specific ERK1/2 pathway inhibitor. Additionally, hPDLCs were transfected with adenoviral vector encoding dominant negative ERK1/2 (DN-ERK1/2) to continuouslyinhibit ERK1/2 activation. The mRNA and protein levels of target geneswere detected through real-time polymerase chain reaction and Western blot. RESULTS: Cyclic stretching promoted the expression of ERK1/2, osteocalcin (OCN) mRNA, and bone sialoprotein (BSP) mRNA. The expression of runt-related transcription factor (Runx) 2 protein and mRNA also increased at 3 and 6 h of cyclic stretching. The inhibition of ERK1/2 by U0126 and DN-ERK1/2 suppressed the expressionof Runx2 mRNA, OCN mRNA, BSP mRNA, Runx 2 protein, and p-ERK1/2 protein relative to that in stretched cells without the ERK1/2 inhibitor. CONCLUSIONS: ERK1/2 is a critical molecule in the mediation ofthe osteogenic differentiation of hPDLCs under mechanical stimulation. ERK1/2 activation induced the elevation of Runx2 protein levels, which may be involved in the stretch-induced expressions of OCN and BSP.

[Effects of geranylgeranyltransferase â gene silencing by RNA interference on the migration and invasion of tongue carcinoma].

OBJECTIVE: RNA interference was used to silence geranylgeranyltransferase Ⅰ(GGTase-Ⅰ) in vitro and to study the effect of GGTase-Ⅰ on the migration and invasion of tongue squamous cancer cells. METHODS: Three small interfering RNAs (siRNA) were designed according to the GGTase-Ⅰ sequence by Genebank and were transfected into tongue squamous cancer cells Cal-27 to knock down GGTase-Ⅰ expression. The tested cells were divided into three groups, as follows: the RNA-interfered groups (GGTase-Ⅰ siRNA1, GGTase-Ⅰ siRNA 2, GGTase-Ⅰ siRNA 3), a negative control group (disrupted by random sequence NC-siRNA), and a blank control group. GGTase-Ⅰ and RhoA gene expressions were examined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. The optimum interference group was screened by qRT-PCR and Western blot and was assigned as the experimental group. Matrix metalloproteinase (MMP)-2 and MMP-9 protein expressions were examined by Western blot. GTP-RhoA expression of protein was examined by GST-pull down. The migration and invasion abilities were analyzed by wound healing assay and Transwell motility assay. RESULTS: GGTase-Ⅰ mRNA and protein expression in Cal-27 decreased significantly after transfection of GGTase-I siRNA (P<0.05). No significant difference of RhoA gene expression was detected. MMP-2, MMP-9, and GTP-RhoA protein expressions decreased significantly (P<0.05). The migration and invasion abilities were inhibited (P<0.05). CONCLUSIONS: To inhibit GGTase-Ⅰ expression, the migration and invasion abilities of tongue squamous cancer cells should also be inhibited. Further studies on GGTase-Ⅰ may provide novel effective molecular targets for tongue squamous cancer cells.