Objective To investigate the level of MEF2C phosphorylation (activation) and protein expression, and to further clarify the possible mechanism following ischemia-reperfusion in hippocampal CA1 region of rat. MethodsBrain ischemia was induced by four-vessel occlusion in SD rats. Protein level was determined by Western blotting. Results MEF2C was significantly activated with a peak at 6 h of reperfusion, but its protein expression decreased in late phase of reperfusion (3～5 d). The elevation of activated (17 ku) and the inactivated forms (32 ku) of caspase-3 proteases were remarkable during 1～5 d of reperfusion. In addition, Ac-DEVD-CHO, a specific inhibitor of caspase-3, up-regulated MEF2C protein level of 3 d reperfusion. SB202190 (an inhibitor of P38), but not ERK5-antisense oligonucleotides, not only inhibited MEF2C activation of 6 h reperfusion but also apparently prevented the increase of caspase-3 activation caused by 3 d reperfusion. Conclusion P38/caspase-3 mediated MEF2C pathway may function in the injuries of hippocampal CA1 region of rats following ischemia/reperfusion.

Objective To evaluate the effects of age factors on the pharmacokinetics of ropivacaine during combined lumbar plexus-sciatic nerve block in patients.Methods Twenty patients of both sexes,aged ≥ 18 yr,weighing 50-75 kg,of American Society of Anesthesiology physical status Ⅰ or Ⅱ,scheduled for elective lower extremity surgery,were divided into 2 groups (n=10 each) according to age:young and middle-aged group (18-59 yr) and elderly group (≥ 60 yr).Combined lumbar plexus-sciatic never block was performed using an ultrasonic instrument and a nerve stimulator.Lumbar plexus block was performed with 0.5％ ropivacaine 30 ml.Sciatic never block was performed with 2％ lidocaine 10 ml plus 0.75％ ropivacaine 10 ml.Before administration and at 5,10,15,20,30,45,60,120,180 and 360 min after administration,blood samples were collected from the radial artery for determination of the blood concentration of ropivacaine by high-performance liquid chromatography.The area under the concentrationtime curve,maximum concentration (Cmax),time to C terminal elimination half-life and clearance were calculated.Results Compared with young and middle-aged group,the blood concentration of ropivacaine was significantly decreased at 5-45 min after administration,the Cmax was significantly decreased,terminal elimination half-life was significantly prolonged (P＜0.05),and no significant change was found in area under the concentration-time curve,the time to C and clearance in elderly group (P＞ 0.05).Conclusion Age factors can affect the pharmacokinetics of ropivacaine during combined lumbar plexus-sciatic nerve block,and both absorption and metabolism of ropivacaine are slower in elderly patients than in young and middle-aged patients.

Objective To evaluate ultrasound-guided posterior approach to intercostal block for herpetic neuralgia. Methods Forty-eight patients with herpetic neuralgia after appearance of rashes on the back of chest (the coursc ＜ 30 days) aged 56-84 yr received intercostal block performed via posterior approach under the guidance of ultrasound with a mixture of 0.75% ropivacaine, glucocorticoid and methylene blue. Pain was assessed with visual analogue scale (VAS) before block and at 1, 2, 4 and 8 weeks after block. Pain relief (PAR) was cal-culated (PAR= (VAS score before block- VAS score after block) ÷ VAS score before block × 100%). Results No patient developed dyspnea and pneumothorax. VAS scores were reduced significantly, quality of life was improved and PAR increased at 1, 2, 4 ancl 8 weeks after block ( P ＜ 0.05 or 0.01). Concluslon Ultracound-guided posterior approach to intercostal block is safe and effective for the treatment of herpetic neuralgia.

Objective To evaluate the efficacy of continuous lumbar plexus block (CLPB) combined with a bolus dose added at night for postoperative analgesia in patients undergoing hip arthroplasty.Methods Sixty ASA Ⅰ or Ⅱ patients of both sexes,aged 51-75 yr,weighing 47-77 kg,with body height 150-180 cm,scheduled for hip arthroplasty,were randomized to receive either CLPB (group CLPB) or patient-controlled intravenous analgesia (PCIA) (PCIA group) for postoperative analgesia (n =30 each).Spinal anesthesia was performed at L3,4 interspace.Postoperative analgesia was performed at 30 min before the end of surgery.PCIA solution contained morphine 100 mg in 100 ml of normal saline.The PCA pump was set up with a 2 mg bolus dose and a 5 min lockout interval.CLPB solution contained 0.125 ％ ropivacaine hydrochloride 200 ml.CLPB pump was set up to deliver a 4 ml bolus dose with a 30-min lockout interval and background infusion at 8 ml/h after a loading dose of 0.125％ ropivacaine 30 ml.In addition the patients received 0.25％ ropivacaine 30 ml at 8 o' clock every night after surgery in group CLPB.VAS scores at rest and during activity were recorded at 6,12,18,24,30,36,42 and 48h after operation.The side effect such as nausea and vomiting,pruritus and urinary retention were recorded within 48 h after operation.The patient' s satisfaction was assessed.The maximal hip flexion and abduction ranges of motion were recorded at 12,24,36 and 48 h after operation.The times of sleep interruption resulted from pain during nighttime were also recorded.Results Compared with group PCIA,the VAS scores during activity,severity of nausea and vomiting,pruritus and urinary retention,and times of sleep interruption resulted from pain during nighttime were significantly decreased,and the overall satisfaction score and maximal hip flexion and abduction ranges of motion were increased in group CLPB (P ＜ 0.05).Conclusion CLPB combined with a bolus dose added at night can provide better efficacy for postoperative analgesia in patients undergoing hip arthroplasty than PCIA,with fewer complications.

Objective To evaluate the effect of ultrasound-guided mid-humeral block on the motor function of upper extremities of the patients undergoing day-case surgery in a department of hand surgery. Methods Thirty patients,weighing 50-75kg,aged 18-64 yr,of American Society of Anesthesiologists physical statusⅠ-Ⅲ,scheduled for elective hand,wrist or forearm surgery,were divided into group Ⅰ(n=15)and group Ⅱ(n=15)using a random number table. Ultrasound-guided mid-humeral block was performed in group Ⅰ,and ultrasound-guided supraclavicular brachial plexus block was performed in group Ⅱ,both with 0.375% ropivacaine 25ml. The onset time of sensory block,recovery time of sensory function,recovery time of motor function of shoulder and elbow joints,allowable hospital discharge time and patient′s satisfaction were recorded. Results Compared with group Ⅱ,the onset time of sensory block,recovery time of motor function of shoulder and elbow joints and allowable hospital discharge time were significantly shortened,and the degree of patient′s satisfaction was increased in group Ⅰ(P<0.01).There were no significant differences in the recovery time of sensory function between the two groups(P＞0.01).Conclusion Ultrasound-guided mid-humeral block has shorter onset time and less influence on the motor function of upper extremities than ultrasound-guided supraclavicular brachial plexus block in the patients undergoing day-case surgery in a department of hand surgery.

Objective To evaluate the efficacy of the anterior approach to quadratus lumborum block in each abdominal and back region.Methods Twelve healthy volunteers of both sexes,aged 18-45 yr,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,with body mass index of 18-30 kg/m2,were enrolled in the study.Quadratus lumborum block was performed via the anterior approach under the guidance of ultrasound with 0.375％ ropivacaine 20 ml.The block was assessed by cold stimulation (ice cake) in each abdominal and back region (the right side of the body was divided into 15 regions using the anatomical landmarks on the body surface).The positive condition in each region was recorded at 30 min after administration.Results The region in which the positive rate ≤ 5％ was 0.The regions in which the positive rate ＞5％-20％ were 1 and 13 regions.The regions in which the positive rate ＞20％-50％ were 2,3 and 4 regions.The regions in which the positive rate ＞50％-70％ were 6,7 and 10 regions.The regions in which the positive rate ＞70％-＜95％ were 5,14 and 15 regions.The regions in which the positive rate ≥95％ were 8,9,11 and 12 regions.Conclusion The anterior approach to quadratus lumborum block is effective in the middle-lower region of the anterior abdominal wall on the blocked side.