Electroacupuncture preconditioning protects against focal cerebral ischemia/reperfusion injury via suppression of dynamin-related protein 1.

Electroacupuncture preconditioning at acupoint Baihui (GV20) can reduce focal cerebral ischemia/reperfusion injury. However, the precise protective mechanism remains unknown. Mitochondrial fission mediated by dynamin-related protein 1 (Drp1) can trigger neuronal apoptosis following cerebral ischemia/reperfusion injury. Herein, we examined the hypothesis that electroacupuncture pretreatment can regulate Drp1, and thus inhibit mitochondrial fission to provide cerebral protection. Rat models of focal cerebral ischemia/reperfusion injury were established by middle cerebral artery occlusion at 24 hours after 5 consecutive days of preconditioning with electroacupuncture at GV20 (depth 2 mm, intensity 1 mA, frequency 2/15 Hz, for 30 minutes, once a day). Neurological function was assessed using the Longa neurological deficit score. Pathological changes in the ischemic penumbra on the injury side were assessed by hematoxylin-eosin staining. Cellular apoptosis in the ischemic penumbra on the injury side was assessed by terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling staining. Mitochondrial ultrastructure in the ischemic penumbra on the injury side was assessed by transmission electron microscopy. Drp1 and cytochrome c expression in the ischemic penumbra on the injury side were assessed by western blot assay. Results showed that electroacupuncture preconditioning decreased expression of total and mitochondrial Drp1, decreased expression of total and cytosolic cytochrome c, maintained mitochondrial morphology and reduced the proportion of apoptotic cells in the ischemic penumbra on the injury side, with associated improvements in neurological function. These data suggest that electroacupuncture preconditioning-induced neuronal protection involves inhibition of the expression and translocation of Drp1.

[Efficacy and delivery outcomes of women underwent double-catheter epidural block during labor].

OBJECTIVE: To investigate the efficacy and pregnancy outcomes of women receiving double-catheter epidural block in labor analgesia, and compare the results with single-catheter epidural block. METHODS: A double-blind clinical trial was conducted on 206 full-term singleton primiparas, aged 25 - 35 and at the 37 - 42 weeks of gestation who delivered at the Department of Obstetrics, Qingdao Municipal Hospital from August 2006 to December 2008, which were randomly divided into two groups: double-catheter epidural block (group D, n = 103) and single-catheter epidural-block (group S, n = 103). Women in group D were given mixture of 0.1% repivacaine hydrochloride and 0.5 mg/L sufentinil 4 - 6 ml as initial dose. Patient control epidural analgesia pump (PCEA) was connected with the upper catheter after 45 minutes. A bolus dose of 4 - 6 ml analgesia mixture was infused according to the condition through the lower catheter. Women in group S received analgesia mixture 10 - 15 ml as initial dose and PCEA pump was connected after 45 minutes. Oxytocin was infused in both groups according to uterine contraction after 30 minutes. The following indexes was observed: (1) visual analogue scales (VAS); (2)modified Bromage Scores; (3) the total dose of analgesia mixture, the percentage of oxytocin infusion, duration of labor and duration of the second stage of labor; (4) fetal birth weight and Apgar scores (1, 5 minutes); (5) mode of delivery; (6) the concentration of plasma cortisol and angiotension II at the beginning of regular uterine contraction and at the time when cervical dilated to 4 cm and 10 cm and fetal disengagement; (7) anesthesia-related complications. RESULTS: (1) The neonatal birth weight and Apgar scores (1, 5 minutes) of group D were (3456 ± 468) g, 9.8 ± 0.6 and 9.9 ± 0.7, respectively, while (3399 ± 569) g, 9.8 ± 0.5 and 9.9 ± 0.7 in group S (P > 0.05). No motor function block was reported in any group and the modified Bromage score was zero. (2) The total dose of analgesia mixture in group D was similar to that in group S [(57 ± 9) ml vs. (58 ± 11) ml, P > 0.05]. However, the percentage of women received oxytocin in group D was smaller [59.2% (61/103) vs. 81.6% (84/103), P < 0.01], and the total time of labor and the duration of second stage of labor in group D were shorter [(532 ± 140) minutes vs. (608 ± 150) minutes; (46 ± 31) minutes vs. (60 ± 34) minutes, P < 0.05]. (3) There were no significant differences in VAS at 30 minutes after initial dose and in the first stage of labor between group D and S (1.2 ± 1.1 vs 1.2 ± 1.1, 1.1 ± 1.1 vs. 1.2 ± 1.0, P > 0.05). VAS at the second stage of labor stage was lower in group D than in group S (1.2 ± 1.1 vs. 4.5 ± 2.2, P < 0.01). (4) The rate of cesarean section, instrumental delivery and episiotomy in group D were lower than in group S (7.8% vs. 17.5%, 7.8% vs. 15.5%, 10.7% vs. 18.4%, P < 0.05). The incidence of fetal distress and meconium-stained amniotic fluid as the indication of cesarean section were similar between the two groups (P > 0.05). Lower incidence of fetal malpresentation and arrested second stage of labor were shown in group D than in group S (2.9% vs. 9.7%, 1.0% vs. 5.8%, P < 0.05). (5) The concentration of plasma cortisol and angiotension II were lower in group D than in group S [(86 ± 25) ng/L vs. (100 ± 20) ng/L, (278 ± 53) nmol/L vs. (311 ± 53) nmol/L, P < 0.05] only at the end of second stage of labor, but not at any other times (P > 0.05). (6) No serious anesthesia-related complications were reported in any groups. Some light backache around the puncture point were complained by 29.1% (30/103) of the women in group D and 31.1% (32/103) in group S (P > 0.05). CONCLUSION: Double-catheter epidural block can provide better analgesia effect during labor than single-catheter epidural block, without any adverse influence on delivery outcomes.

[Partial nitrification of digested sludge liquor with low C/N and high-concentration ammonia].

The experimental system consisted of anoxic filter and aerobic suspended carrier biofilm reactor. The partial nitrification was achieved and maintained stably in the aerobic reactor under normal temperature (15-29 degrees C) and high DO (6-9 mg/L). The nitritation with 70%-80% nitrite accumulation efficiency was obtained when FA concentration was in the range of 1.0-10.3 mg/L by controlling influent ammonia loading rate (ALR), ratio of alkalinity and ammonia and HRT in the aerobic reactor. The effluent nitrite/ammonia ratio was about 1.25 when the average influent ammonia, influent ALR and influent ratio of alkalinity and ammonia were 315.80 mg/L, 0.43 kg/(m3 x d) and 5.25, respectively. So the effluent of partial nitrification process provided the influent substrate demand for the following ANAMMOX process. The integrative analysis indicated that the proper FA concentration was the main factor achieving the partial nitrification. The study developed a novel partial nitrification technology adapt to water characteristics of digested sludge liquor.