Objective To investigate the influence of RNA interference targeting c-Jun gene on the proliferation of rat vascular smooth muscle cells (VSMCs). Methods The experiment was performed with c-Jun siRNA （c-Jun siRNA group）, control reverse sequence siRNA (control siRNA group) or no siRNA (control group). VSMCs were transfected with siRNA targeting c-Jun gene by liposome. Effects of c-Jun siRNA on mRNA and protein expressions of c-Jun were examined by RT-PCR analysis and Western blot respectively. MTT test and 3H-TdR incorporation were used to detect VSMCs proliferation. Cell cycle analysis of VSMCs in vitro was determined by flow cytometer. Results The expression levels of mRNA and protein of c-Jun in c-Jun siRNA group were significantly lower than those in control group （P＜0.05， P＜0.01). There was no significant difference between control group and control siRNA group （Pgt;0.05）. Proliferation activity of VSMCs decreased significantly in c-Jun siRNA group compared with that in control group （P＜0.05） and VSMCs was blocked in the G0/G1 phase of cell cycle significantly （P＜0.05）. There was no significant difference between control group and control siRNA group （Pgt;0.05）. Conclusion c-Jun gene silenced by RNA interference can inhibit VSMCs proliferation effectively in vitro.
ObjectiveTo evaluate the correlation between positive end-expiratory pressure (PEEP) level and postoperative pulmonary complications (PPCs) in patients undergoing thoracoscopic lung surgery. MethodsThe clinical data of patients who underwent elective thoracoscopic lung surgery at West China Hospital of Sichuan University from January 2022 to June 2023 were retrospectively analyzed. Patients were divided into 2 groups according to intraoperative PEEP levels: a PEEP 5 cm H2O group and a PEEP 10 cm H2O group. The incidence of PPCs in the two groups after matching was compared using a nearest neighbor matching method with a ratio of 1∶1, setting the clamp value as 0.02. ResultsA total of 538 patients were screened, and after propensity score-matching, a total of 229 pairs (458 patients) were matched, with an average age of 53.9 years and 69.4% (318/458) females. A total of 118 (25.8%) patients had PPCs during hospitalization after surgery, including 60 (26.2%) patients in the PEEP 5 cm H2O group and 58 (25.3%) patients in the PEEP 10 cm H2O group, with no statistically significant difference between the two groups [OR=0.997, 95%CI (0.495, 1.926), P=0.915]. Multivariate logistic regression analysis showed that PEEP was not an independent risk factor for PPCs [OR=0.920, 95%CI (0.587, 1.441), P=0.715]. ConclusionFor patients undergoing thoracoscopic lung surgery, intraoperative PEEP (5 cm H2O or 10 cm H2O) is not associated with the risk of PPCs during hospitalization after surgery, which needs to be further verified by prospective, large-sample randomized controlled studies.
Objective To investigate the relationship between the gastrointestinal function and ventilator-associated pneumonia (VAP) in critically ill patients who underwent invasive mechanical ventilation. Methods One-hundred and fifty-three cases of critically ill patients receiving mechanically ventilation were recruited in the study. After 5 days of ventilation, the gastrointestinal function score and the C-reactive protein (CRP) of each patient were recorded. The incidence of VAP was recorded during hospitalization. According to the incidence of VAP, all patients were divided intoaVAP group and a non-VAP group. The relationship between gastrointestinal function score and the incidence of VAP was analyzed. The relationship between CRP level and severity degree of VAP was also analyzed. Results VAP occurred in 42 cases with the incidence of 27.45%. The gastrointestinal function score (1.9±1.0 vs. 0.8±1.0, P < 0.05) and CRP level [(52.38±12.06) mg/L vs. (36.69±11.08)mg/L, P < 0.05] were both higher in the VAP group than those in the non-VAP group. At gastrointestinal function score of 0 - 3, the CRP levels were all higher in the VAP group than those in the non-VAP group (P < 0.05). The incidence of VAP was 8.33%, 23.68%, 45.45%, and 59.09% at gastrointestinal function score of 0, 1, 2 and 3, respectively, with significant differences between each other(P < 0.05). Conclusion For critically ill patients receiving invasive mechanical ventilation, the more severe the damage of gastrointestinal function is, the higher the incidence of VAP is, and the more serious the disease is.
Objective To investigate the effects of long time different negative pressures on osteogenic diffe-rentiation of rabbit bone mesenchymal stem cells (BMSCs). Methods The rabbit BMSCs were isolated and cultured by density gradient centrifugation. Flow cytometry was used to analyze expression of surface markers. The third passage cells cultured under condition of osteogenic induction and under different negative pressure of 0 mm Hg (control group), 75 mm Hg (low negative pressure group), and 150 mm Hg (high negative pressure group) (1 mm Hg=0.133 kPa), and the negative pressure time was 30 min/h. Cell growth was observed under phase contrast microscopy, and the growth curve was drawn; alkaline phosphatase (ALP) activity was detected by ELISA after induced for 3, 7, and 14 days. The mRNA and protein expressions of collagen type I (COL-I) and osteocalcin (OC) in BMSCs were analyzed by real-time fluorescence quantitative PCR and Western blot. Results The cultured cells were identified as BMSCs by flow cytometry. The third passage BMSCs exhibited typical long shuttle and irregular shape. Cell proliferation was inhibited with the increase of negative pressure. After induced for 4 days, the cell number of high negative pressure group was significantly less than that in control group and low negative pressure group (P<0.05), but there was no significant difference between the low negative pressure group and the control group (P>0.05); at 5-7 days, the cell number showed significant difference between 3 groups (P<0.05). The greater the negative pressure was, the greater the inhibition of cell proliferation was. There was no significant difference in ALP activity between groups at 3 days after induction (P>0.05); the ALP activity showed significant difference (P<0.05) between the high negative pressure group and the control group at 7 days after induction; and significant difference was found in the ALP activity between 3 groups at 14 days after induction (P<0.05). The greater the negative pressure was, the higher the ALP activity was. Real-time fluorescence quantitative PCR and Western blot detection showed that the mRNA and protein expressions of COL-I and OC protein were significantly higher in low negative pressure group and high negative pressure group than control group (P<0.05), and in the high negative pressure group than the low negative pressure group (P<0.05). Conclusion With the increase of the negative pressure, the osteogenic differentiation ability of BMSCs increases gradually, but the cell proliferation is inhibited.