AIM: To observe the effect of simvastatin on the proliferation of vascular smooth muscle cells(VSMCs) induced by serum and growth factor PDGF-BB and the effect of simvastatin on the expression of PTEN,a important regulator of G 1/S cell cycle transition. METHODS: The DNA synthesis was determined by -TdR incorporation, cell cycle was examined with flow cytometry, the protein level of PTEN was measured by Western blot method. RESULTS: (1)Simvastatin inhibited -TdR incorporation in a dose dependent manner. (2) Flow cytometric DNA analysis revealed that simvastatin induced significantly enhancement of G 0/G 1 phase and decrease in S phase VSMCs.(3)Simvastatin increased protein level of PTEN and mevalonate, a metabolite of HMG-COA, reversed the effect of simvastatin on PTEN protein expression. CONCLUSION: Simvastatin may inhibit proliferation of VSMCs and retarded cell cycle in G 0/G 1 phase by increasing PTEN expression through inhibiting synthesis of mevalonate.

AIM: Hydroxymethylglutaryl CoA (HMG-CoA) reductase inhibitors, such as simvastatin, have been shown to reduce atherosclerotic cardiovascular morbidity and mortality by mechanisms unrelated to its lipid-lowering effect. Several studies have shown that simvastatin induces apoptosis in a varieties of cell lines including vascular smooth muscle cells (VSMC). The aim of this study was to investigate the signal pathways involved in apoptosis induced by simvastatin. METHODS: Cultured VSMC were treated with simvastatin. Calpain activity was determined by measuring Ca 2+ ionophore-specific calpain substrate (suc-LLVY-AMC), caspase-3 activation was detected by Western blot, and apoptotic changes were distinguished by annexin Ⅴ binding and DNA laddering. RESULTS: After incubated with 30 ?mol/L simvastatin for 8 h, calpain activity had a marked increase ( P

Two Pseudomonas strains, K80 - B and K80 - A, can use hydrocarbon as carbon source by two different mechanisms. Different effects can be observed when they are applied to 69-8 oil of Dagan Oil Field. The strain K80-B producing both hydrocarbon pseudosolubilizing factor and hydrocarbon emulsifying factor can decrease the viscosity and solidifying point of the 69-8 oil 51.6% and 2℃ respectively. Whereas the other can only decrease 43.5% and 3℃ respectively. When the two strains are mixed, synergistic effect on crude oil is obvious.

Objective:To compare the antiosteoporosis effect of conventional treatment and conventional treatment combined with Denosumab after percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fractures (OVCF).Methods:A retrospective cohort study was conducted to analyze the clinical data of 211 patients with OVCF admitted to the Second Affiliated Hospital of Soochow University from September 2020 to September 2022. All the patients were female, aged 56-90 years [(71.4±8.1)years]. The bone mineral density T-score of the lumbar spine was (-2.6±1.0)SD before operation. Fracture segments included T 1-T 9 in 45 patients, T 10-L 2 in 146, and L 3-L 5 in 69. Of all, 174 patients were treated with single-segment surgery, 25 with two-segment surgery and 12 with surgery involving three or more segments. According to the wishes of the patients, 107 patients were treated with daily oral administration of calcium and active Vitamin D after PKP (conventional treatment group) and 104 patients with Denosumab combined with the conventional treatment after PKP (Denosumab therapy group). The bone mineral density T-scores of the lumbar spine of the two groups were compared before surgery and at the last follow-up. The visual analogue scale (VAS) and Oswestry disability index (ODI) before surgery, at 3 days, 6 months after surgery, and at the last follow-up were evaluated and the refracture rate after surgery was detected. Possible adverse effects after medication during anti-osteoporosis treatment were observed in two the groups. Results:All the patients were followed up for 12-24 months [(13.5±2.0)months]. Before surgery, the bone mineral density T-score of the lumbar spine was (-2.7±1.1)SD in the Denosumab therapy group and (-2.5±0.8)SD in the conventional treatment group ( P>0.05). At the last follow-up, the bone mineral density T-score of the lumbar spine was (-2.1±1.1)SD in the Denosumab therapy group, significantly higher than (-2.5±0.9)SD in the conventional treatment group ( P<0.05). In the Denosumab therapy group, the bone mineral density T-score of the lumbar spine at the last follow-up was significantly increased compared to that before surgery ( P<0.01), while there was no significant difference in the conventional treatment group ( P<0.05). Before surgery and at 3 days after surgery, the VAS scores and ODI values were (8.5±0.9)points, (2.8±0.8)points, 48.7±4.8 and 25.6±4.0 in the Denosumab therapy group, which was not statistically different from those in the conventional treatment group [(8.5±1.3)points and (2.8±0.9)points, 47.9±7.0 and 25.9±3.7] ( P>0.05). At 6 months after surgery and at the last follow-up, the VAS scores and ODI values were (2.2±0.8)points, (1.7±0.8)points, 24.2±3.6 and 23.2±4.1 in the Denosumab therapy group, significantly lower than those of the conventional treatment group [(2.8±0.9)points, (2.8±1.1)points, 26.4±3.2 and 27.3±4.0] ( P<0.01). The VAS scores at each time point after surgery in both groups decreased significantly compared with those before surgery ( P<0.05). The VAS scores continued to decrease after surgery in the Denosumab therapy group ( P<0.05), while no significant difference was found among those at different time points in the conventional treatment group ( P>0.05). The ODI values at each time point after surgery in both groups significantly decreased compared to those before surgery ( P<0.05). The ODI values continued to decrease after surgery in the Denosumab therapy group ( P<0.05), while in the conventional treatment group, no significant difference was found between those at 6 months after surgery and those at 3 days after surgery ( P>0.05) and they were improved at the last follow-up compared with those at 3 days after surgery ( P<0.05). The refracture rate after surgery was 6.7% (7/104) in the Denosumab therapy group, significantly lower than 16.8% (18/107) in the conventional treatment group ( P<0.05). No serious complications were observed during the antiosteoporosis period in either group. Conclusion:Compared with daily oral administration of Calcium and active Vitamin D after PKP, the conventional treatment combined with Denosumab after PKP can effectively increase the bone density, relieve pain continuously, improve functional restoration, and reduce the risk of refracture in OVCF patients.

Objective:To evaluate the effect of zoledronic acid administration for osteoporotic vertebral compression fracture (OVCF) after treatment with percutaneous kyphoplasty (PKP).Methods:A retrospective case-control study was performed on 430 elderly patients with OVCF admitted to the Second Affiliated Hospital of Soochow University from January 2012 to December 2016. There were 31 males and 399 females, with age of 52-92 years[(72.8±8.3)years]. Fracture segments were at T 5-T 10 (82 vertebrae), T 11-L 2 (389 vertebrae) and L 3-L 5 (173 vertebrae). In zoledronic acid group ( n=178), patients were given zoledronic acid 3 days after PKP surgery. In basic treatment group ( n=252), patients were only given basic treatment after PKP surgery. Bone mineral density was measured before operation and one year after operation. Visual analogue scale (VAS) and Oswestry disability index (ODI) were assessed before operation, 3 days and one year after operation. Incidence rate of refracture, mortality and complication rate were recorded after operation. Results:All patients were followed up for 12-60 months (mean, 27 months). Before operation and at postoperative 1 year, the vertebral bone mineral density in zoledronic acid group was (-2.3±1.5)SD and (-1.2±2.3)SD ( P<0.05), and that in basic treatment group was (-2.2±1.2)SD and (-2.1±1.1)SD ( P>0.05). At postoperative 1 year, the bone mineral density in zoledronic acid group was significantly better than that in basic treatment group ( P<0.05). At preoperative 3 days, postoperative 3 days and postoperative 1 year, the VAS was (8.6±0.8)points, (2.8±0.8)points, (2.1±0.8)points in zoledronic acid group, and was (8.5±1.1)points, (2.9±0.9)points, (3.0±2.3)points in basal treatment group; ODI was 48.7±5.3, 24.0±2.9, 22.3±3.3 in zoledronic acid group, and was 48.3±6.1, 24.5±3.8, 27.6±4.0 respectively in basal treatment group. The VAS and ODI were significantly reduced in two groups at postoperative 3 days and 1 year compared to those before operation ( P<0.05). Moreover, the VAS and ODI in zoledronic acid group were significantly lower than those in basal treatment group at postoperative 1 year ( P<0.05). At postoperative 2 years, the incidence rate of refracture in zoledronic acid group was 10.1%(18/178), significantly lower than 16.7%(43/252) in basic treatment group ( P<0.05). Mortality rate in zoledronic acid group was 5.1%(9/178), and that in basic treatment group was 6.3%(16/252) ( P>0.05). No serious complications were observed in both groups such as nerve injury or pulmonary embolism. Conclusion:For OVCF patients, zoledronic acid given after PKP can improve the bone mineral density, reduce pain, fasten function recovery, and effectively decrease the refracture rate.

Objective:To compare the clinical efficacy of robot-assisted percutaneous screw implantation and free-hand open screw implantation by Wiltse approach in the treatment of thoracolumbar fracture.Methods:A retrospective cohort study was performed to analyze the clinical data of 71 patients with thoracolumbar fracture admitted to Second Affiliated Hospital of Soochow University from May 2018 to May 2020. There were 52 males and 19 females, with age range of 22-54 years［(41.0±7.8)years］. Of all, 33 patients were treated with robot-assisted percutaneous screw implantation (Group A) and 38 patients were treated with free-hand open screw implantation by Wiltse approach (Group B). Following parameters were measured, including frequency of radiation exposure, operation time, intraoperative blood loss, length of hospital stay, incidence of complications, rate of fracture healing at 3 months and 6 months postoperatively, visual analogue scale (VAS) and Oswestry dysfunction index (ODI) at 3 days, 3 months, 6 months postoperatively and at the last follow-up, anterior vertebral body height ratio and sagittal Cobb angle preoperatively, at 3 days postoperatively and at the last follow-up, and rate of screw implantation of grade A and B and rate of facet joint violation at 3 days postoperatively.Results:All patients were followed up for 10-24 months［(15.2±4.4)months］. Frequency of radiation exposure and operation time showed no statistical differences between the two groups (both P>0.05). Intraoperative blood loss was 100(100, 135)ml in Group A, less than 160(120, 200)ml in Group B ( P<0.01). Length of hospital stay was 8(7, 11) days in Group A, shorter than 12(10, 16)days in Group B ( P<0.01). There were no complications such as infection, spinal nerve injury or cerebrospinal fluid leakage in both group. There were no significant differences between the two groups in the rate of fracture healing at 3 and 6 months postoperatively (all P>0.05). VAS and ODI in Group A was 3(2, 4)points and 21(18, 23)points at 3 days postoperatively, lower than 4 (3, 5)points and 27(20, 32)points in Group B ( P<0.05 or 0.01), and the two groups showed no significant differences in VAS and ODI at other time points (all P>0.05). There were no significant difference in the anterior vertebral body height ratio or sagittal Cobb angle between the two groups at 3 days postoperatively and at the last follow-up (all P>0.05). Rate of screw implantation of grade A and B was 96.5% (191/198) in Group A, higher than 90.4% (206/228) in Group B ( P<0.05). Rate of facet joint violation was 4.0%(8/198) in Group A, lower than 11.8% (27/228) in Group B ( P<0.01). Conclusion:For thoracolumbar fracture, robot-assisted percutaneous screw implantation is superior to free-hand open screw implantation by Wiltse approach in terms of less bleeding, shorter hospitalization, earlier pain alleviation, higher accuracy of screw implantation and lower risk of facet joint violation.

Periodontitis is an inflammatory disease that is characterized by progressive destruction of the periodontium and causes tooth loss in adults.Periodontitis is known to be associated with dysbiosis of the oral microflora,which is often linked to various diseases.However,the complexity of plaque microbial communities of periodontitis,antibiotic resistance,and enhanced virulence make this disease difficult to treat.In this study,using metagenomic shotgun sequencing,we inves-tigated the etiology,antibiotic resistance genes(ARGs),and virulence genes(VirGs)of periodontitis.We revealed a significant shift in the composition of oral microbiota as well as several functional pathways that were represented significantly more abundantly in periodontitis patients than in con-trols.In addition,we observed several positively selected ARGs and VirGs with the Ka/Ks ratio＞1 by analyzing our data and a previous periodontitis dataset,indicating that ARGs and VirGs in oral microbiota may be subjected to positive selection.Moreover,5 of 12 positively selected ARGs and VirGs in periodontitis patients were found in the genomes of respiratory tract pathogens.Of note,91.8％of the background VirGs with at least one non-synonymous single-nucleotide polymorphism for natural selection were also from respiratory tract pathogens.These observations suggest a potential association between periodontitis and respiratory infection at the gene level.Our study enriches the knowledge of pathogens and functional pathways as well as the positive selection of antibiotic resistance and pathogen virulence in periodontitis patients,and provides evidence at the gene level for an association between periodontitis and respiratory infection.

As the demand for high-performance computing continues to grow, traditional computing models are facing unprecedented challenges. Among the many emerging computing technologies, DNA computing has attracted much attention due to its low energy consumption and parallelism. The DNA circuit, which is the basis for DNA computing, is an important technology for the regulation and processing of the molecular information. This review highlights the basic principles of DNA computing, summarizes the latest research progress, and concludes with a discussion of the challenges of DNA computing. Such integrated molecular computing systems are expected to be widely used in the fields of aerospace, information security and defense system.
DNA/genetics*