Objective:To evaluate the effect of ribosomal protein L34 (RPL34) gene knockdown on the proliferation and apoptosis of human cutaneous squamous cell carcinoma (cSCC) cells.Methods:From January 2016 to January 2017, 14 paraffin-embedded skin samples of cSCC and 16 paraffin-embedded normal skin tissue samples were collected from Department of Dermatology and Venereology, the Affiliated Hospital of Inner Mongolia Medical University, and RPL34 expression in the skin tissues was analyzed by immunohistochemical study. A lentivirus vector containing short hairpin RNA targeting RPL34 gene was constructed and used to transfect a human cSCC cell line SCL-1 (shRNA group) , SCL-1 cells transfected with an empty lentivirus vector served as control group, and the knockdown efficiency was verified by real-time quantitative PCR (RT-PCR) and Western blot analysis. At 72 hours after the transfection, flow cytometry was performed to analyze the cell cycle and detect apoptosis of SCL-1 cells, and methyl thiazolyl tetrazolium (MTT) assay to evaluate the cellular proliferative activity of SCL-1 cells. Comparisons between 2 groups were performed by using t test or rank sum test. Results:Immunohistochemical study showed that the cytoplasmic expression score of RPL34 was significantly higher in the cSCC tissues (2.143±1.956) than in the normal control tissues (0.500±0.516, z=3.53, P< 0.05) . RT-PCR showed that the relative mRNA expression of RPL34 in the SCL-1 cells was significantly lower in the shRNA group (0.149±0.016) than in the control group (1±0.018, t=36.95, P< 0.05) ; Western blot analysis revealed that the relative protein expression of RPL34 in the SCL-1 cells was significantly lower in the shRNA group than in the control group. Compared with the control group, the shRNA group showed a significantly increased proportion of S-phase cells ( t=13.76, P< 0.05) , but a significantly decreased proportion of G1-phase cells ( t=36.62, P< 0.05) ; the apoptosis rate was significantly higher in the shRNA group (9.42%±0.16%) than in the control group (4.58%±0.41%, t=19.02, P< 0.05) . MTT assay showed that the cell viability was significantly decreased in the shRNA group (0.815±0.005) than in the control group (1.886±0.005, t=265.91, P< 0.05) after additional 120-hour culture. Conclusion:The RPL34 gene was overexpressed in the cSCC tissues, and knockdown of the RPL34 gene in SCL-1 cells could interfere with cell cycle, decrease their proliferative activity, and promote their apoptosis.

Objective:To investigate the role and related mechanisms of the LiaSR two-component system in acid tolerance and biofilm formation abilities of Streptococcus mutans (Sm) 593. Methods:The growth curves of various Sm strains in pH=5.5 brian heart infusion (BHI) medium were analyzed. And colony forming unit (CFU) was also performed to evaluate the acid tolerance of Sm. Laurdan probe, H +-K +adenosine triphosphate (ATP)ase activity analysis kit, proton permeability assay and real-time fluorescence quantitative PCR (RT-qPCR) were conducted to detect the acid tolerant mechanisms of LiaSR two-component system in Sm. Crystal violet staining, CFU, SYTOX probe and anthrone-sulfuric method were used to analyze the properties and structures of the Sm biofilms. RT-qPCR was conducted to detect the expression levels of underlying regulated genes. Results:The growth of mutants in acidic BHI were inhibited ( P<0.05). The acid tolerance of mutants significantly decreased compared to the wild-type strain ( P<0.05). In mutants, the activity of H +-ATPase (917.06±59.53 and 469.53±47.65) were elevated by 7.22-folds and 3.70-folds compared to the wild-type strain (127.00±50.71) ( P<0.001, P<0.001) and the encoded gene atpD (3.39±0.21 and 1.94±0.17) were also elevated by 3.39-folds and 1.94-folds compared to the wild-type strain (1.00±0.15) ( P<0.001, P=0.001). The Laurdan generalized polarization of mutants (0.18±0.04 and 0.18±0.05) increased significantly compared to the wild-type strain (0.08±0.05) ( P=0.006, P=0.003) and the expression levels of fabM gene were decreased in mutants (0.52±0.11 and 0.57±0.05) by 1/2 ( P=0.014, P=0.022). In liaR deletion mutant, the reduced terminal pH (4.76±0.01) can also be observed ( P<0.001). The total amount of the biofilms of three Sm didn't show significant differences ( P>0.05). But the number of viable bacteria of mutants′ biofilms were decreased [Sm 593: (12.00±2.80)×10 7 CFU/ml; Sm ΔliaS: (2.95±1.13)×10 7 CFU/ml; Sm ΔliaR: (7.25±1.60)×10 7 CFU/ml] ( P=0.001, P=0.024). The extracellular DNA were increased by 18.00-folds and 6.50-folds in mutants′ biofilms (128.73±15.65 and 46.38±5.52) compared to the wild-type strain (7.16±3.62) ( P<0.001, P=0.003). Water-soluble exopolysaccharides could be found up-regulated in liaS deletion mutant [(138.73±10.12) μg/ml] ( P=0.003) along with the expression level of gtfC gene (1.65±0.39) ( P=0.014). The expression level of gtfD were elevated by 47.43-folds and 16.90-folds in mutants ( P<0.001, P=0.010). Conclusions:The LiaSR two-component system can promote the expression of fabM gene and increase the fluidity of Sm which contributes to acid tolerance. The LiaR can also decrease the proton permeability and restrict the entrance of H +. The LiaSR two-component system can negatively regulate the production of the extracellular matrix in Sm biofilm.

Objective: To evaluate the efficacy and safety of Oryz-Aspergillus enzyme and pancreatin tablets (Combizym^®) in the treatment of postprandial distress syndrome (PDS) in the elderly, compared with gastrointestinal motility drugs. Methods: A prospective randomized controlled trial was designed and registered in the China Clinical Trials Registry (ChiCTR-IPR-16008185). The elderly patients with PDS were randomly divided into three groups, including Mosapride group with Mosapride citrate tablets 5 mg 3 times per day for 2 weeks; Combizym^® group with Combizym tablets 244 mg 3 times per day for 2 weeks; combined treatment group with both drugs and same doses for 2 weeks. The modified Nepean dyspepsia index (NDSI) score, discomfort intensity score and PDS score were calculated on patients before treatment, at the end of first and second week of treatment, as well as 4 weeks after treatment finished, respectively. Adverse effects were evaluated. Results: A total of 323 patients from 16 tertiary hospitals in China were enrolled in this study. Among them, 105 patients were in Mosapride group, 109 in Combizym^® group and 109 in combined treatment group. There were 148 males (45.8%) and 175 females (54.2%) with median age 71.4±9.0 years (60-100 years). Baseline characteristics of three groups were comparable. After treatment, the NDSI scores in three groups all decreased significantly (P<0.001), while they were similar between groups (P>0.05). The discomfort intensity score and PDS score in three groups showed a significant reduction after treatment (P<0.001), especially in the combined treatment group. Compared with Mosapride group, the scores in Combizym^® group decreased significantly after one or two weeks [discomfort intensity score: after one week, 4.0(2.5, 8.0) vs. 6.0(3.0, 10.0); after two weeks, 3.0(0.0, 5.0) vs. 4.0(2.0, 6.0); all P<0.05. PDS score: after one week, 6.0(3.0, 9.0) vs. 7.0(3.5, 10.5); after two weeks, 3.0(0.0, 5.0) vs. 4.0(2.0, 7.0); all P<0.05]. The efficacy rate in all patients after first week of treatment was over 15.0%. The efficacy rates after two weeks were 55.2%, 68.8% and 73.4% in Mosapride group, Combizym^® group and combined treatment group, respectively. After two week treatment, the efficacy rates in Combizym^® group (P=0.041) and combined group (P=0.006) were higher than that of Mosapride group. The recurrence rate of Mosapride group was 9.5%, which was significantly higher than that of Combizym^® group (1.8%, P<0.05) and combined treatment group (1.8%, P<0.05). There were no serious adverse effects in the three groups. Conclusions The efficacy of Oryz-Aspergillus enzyme and pancreatin tablets is comparable with that of Mosapride in elderly PDS patients, with fewer adverse effects and low recurrence rate. Combination regimen indicates better efficacy than that of Oryz-Aspergillus enzyme and pancreatin tablets or Mosapride alone.