ABSTRACT
Objective To investigate the role of microRNA-1 (miR-1) in cardiac fibroblasts induced by high glucose in rats. Methods The primary fibroblasts were cultured from the apical tissue of 1-3 day-old Sprague-Dawley (SD) rats. The cells which were passaged to generation 3 or 4, were randomly divided into normal glucose+lentivector-vehicle group (CON+Lv-Vehicle group), normal glucose+lentivector-miR-1 group (CON+Lv-miR1 group), high glucose+lentivector-vehicle group (HG+Lv-Vehicle group), high glucose+lentivector-miR-1 group (HG+Lv-miR1 group), high glucose+Lv-Vehicle+inhibitor group (HG+Lv-Vehicle+CC group), and high glucose+lentivector-miR-1+inhibitor group (HG+Lv-miR1+CC group). The myocardial fibroblasts were cultured in the concentration of 5.5 mmol/L glucose (normal glucose) or 25.0 mmol/L (high glucose) DMEM medium. Then lentiviral vector containing miR-1 silent sequence or the same volume of lentiviral vector was inoculated into the cells. The AMP activated protein kinase (AMPK) inhibitor Compound C (20 μmol/L) was added to the medium at 12 hours before sampling in inhibitor groups. The expression of phosphorylation of AMPK (p-AMPK), collagenⅠandⅢ, matrix metalloproteinase (MMP-2, MMP-9), and autophagy flux related protein LC3B-Ⅱ and p62/SQSTM1 were measured by Western Blot. Results The purity of rat myocardial fibroblasts in vitro was 97%. Compared with CON+Lv-Vehicle group, there was no significant difference in the expression of p-AMPK in CON+Lv-miR1 group, the expression of p-AMPK in HG+Lv-Vehicle group was significantly decreased (p-AMPK/t-AMPK: 44.72±3.29 vs. 100.00±7.77, 1 < 0.01). The expression of p-AMPK in HG+Lv-miR1 group was higher than that in HG+Lv-Vehicle group (p-AMPK/t-AMPK:60.52±5.16 vs. 44.72±3.29, 1 < 0.05). Compared with HG+Lv-Vehicle group, the expressions of collagen, MMP, LC3B-Ⅱand p62/SQSTM1 in HG+Lv-miR1 group were significantly decreased; after the treatment with AMPK inhibitor, the expressions of collagen, MMP, LC3B-Ⅱ, p62/SQSTM1 were significantly increased (HG+Lv-Vehicle+CC group vs. HG+Lv-Vehicle group: collagen Ⅰ/β-actin: 158.74±13.21 vs. 100.00±7.64, collagenⅢ/β-actin: 177.38± 17.31 vs. 100.00±5.18, MMP-2/β-actin: 130.09±14.31 vs. 100.00±10.47, MMP-9/β-actin: 215.54±20.92 vs. 100.00±11.28, LC3B-Ⅱ/β-actin: 159.34±13.83 vs. 100.00±6.44, p62/SQSTM1/β-actin: 201.01±24.02 vs. 100.00±8.62; HG+Lv-miR1+CC group vs. HG+Lv-miR1 group: collagenⅠ/β-actin: 108.69±9.93 vs. 80.83±7.24, collagenⅢ/β-actin: 127.68±10.46 vs. 81.56±9.97, MMP-2/β-actin: 106.66±10.21 vs. 74.80±7.43, MMP-9/β-actin: 145.65±11.56 vs. 74.63±10.55, LC3B-Ⅱ/β-actin: 150.15±13.28 vs. 22.98±2.87, p62/SQSTM1/β-actin: 130.48±10.74 vs. 49.90±2.27, all 1 < 0.05). Conclusion miR-1 gene silencing inhibits myocardial fibrosis induced by high glucose, its mechanism may be related to the up-regulation of p-AMPK, which can recover autophagy flux.
ABSTRACT
BACKGROUND: Inadequate hyperventilation may trigger cerebrovascular contraction and lead to lowered cerebral perfusion and oxygen supply-demand imbalance.OBJECTIVE: To investigate the influence of hyperventilation on oxygen saturation in the internal jugular vein, difference in oxygen and lactic acid contents between the cerebral arteries and veins in patients with serious traumatic brain injury.DESIGN: Case analysis.SETTING: Department of Anesthesiology, First Hospital Affiliated to Shantou University.PARTICIPANTS: Sixteen patients who received emergency operations in the First Hospital Affiliated to Shantou University between January and July 2002.METHODS: Patients with traumatic brain injury underwent operation under general anesthesia, and the PaCO2 was maintained at 30 mm Hg for 15 minutes by regulating the respiration rate, followed by decrease to 25 mm Hg, maintained for 15 minutes before restoration to 30 mm Hg for 15 minutes. The fractional concentration of inspired oxygen was adjusted to maintain blood PaO2 at around 100-150 mm Hg, and the blood sample was collected from the artery and internal jugular vein 15 minutes after adjustment of PaCO2 for blood gas analysis. The PaO2 was then increased to 200-250 mm Hg by increasing the fractional concentration of inspired oxygen, and the PaCO2 was adjusted from 30 to 25 and then back to 30 mm Hg in the described manner, and the oxygen saturation in the internal jugular vein, difference in oxygen and lactic acid contents between the arteries and the veins were measured.MAIN OUTCOME MEASURES: Influence of blood PaO2 and PaCO2 on oxygen saturation in the internal jugular vein, difference in oxygen and lactic acid contents between the arteries and the veins.RESULTS: Sixteen patients met the diagnostic criteria and completed data collection. The arterial PaCO2 decreased from 30 to 25 mm Hg when arterial blood oxygen pressure increased from 100-150 to 200-250 mm Hg, which leads to obvious decrease of oxygen saturation in the internal jugular vein and obvious increased difference in oxygen content between the cerebral artery and vein. However the absolute value of oxygen saturation in the internal jugular vein was obviously higher at PaO2 of 200-250 mm Hg than that at PaO2 of 100-150 mm Hg, while the absolute value of cerebral arteriovenous difference of brain oxygen content was obviously lower. Compared to the basal level, the arteriovenous lactic acid difference was obviously increased at PaO2 of 100-150 mm Hg,PaCO2 of 30 and 25 mm Hg, and at PaO2 of 200-250 mm Hg and PaCO2 of 25 mm Hg.CONCLUSION: Relatively higher PaO2 (200-250 mm Hg) and mild hyperventilation (PaCO2 of 30 mm Hg) has no obvious effect on brain oxygen supply-demand balance.
ABSTRACT
Objective To investigate the preemptive analgesic effects of somato-visceral blockade in laparoscopic cholecystectomy (LC). Methods One hundred patients were randomly divided into four groups: Group A received peri-portal infiltration of 25 ml 0.25% bupivacaine (contained 1:200 000 epinephrine) before incision; Group B received intraperitoneal spray of 35ml 0.25% bupivacaine immediately after the establishment of pneumoperitoneum; Group C received the management of both Group A and Group B; Group D was control group without management. The extent and location of pain and nausea were recorded and assessed at 1, 2, 3, 6, 12, 24 and 48 postoperative hours, respectively. Results In the control group the incisional pain dominated over other pain locations within 24 hours postoperatively (P