ObjectiveTo analyze the protective mechanism of spinal cord ischemia-reperfusion injury mediated by N-methyl-D-aspartate (NMDA) receptor.MethodsA total of 42 SD rats were randomly assigned to 4 groups: a non-blocking group (n=6), a saline group (n=12), a NMDA receptor blocker K-1024 (25 mg/kg) group (n=12) and a voltage-gated Ca2+ channel blocker nimodipine (0.5 mg/kg) group (n=12). The medications were injected intraperitoneally 30 min before ischemia. The neural function was evaluated. The neuronal histologic change of spinal cord lumbar region, the release of neurotransmitter amino acids and expression of spinal cord neuronal nitric oxide synthase (nNOS) were compared.ResultsAt 8 h after reperfusion, the behavioral score of the K-1024 group was 2.00±0.00 points, which was statistically different from those of the saline group (5.83±0.41 points) and the nimodipine group (5.00±1.00 points, P<0.05). Compared with the saline group and nimodipine group, K-1024 group had more normal motor neurons (P<0.05). There was no significant difference in glutamic acid concentration in each group at 10 min after ischemia (P=0.731). The nNOS protein expression in the K-1024 group was significantly down-regulated compared with the saline group (P<0.01). After 8 h of reperfusion, the expression of nNOS protein in the K-1024 group was significantly up-regulated compared with the saline group (P<0.05).ConclusionK-1024 plays a protective role in spinal cord ischemia by inhibiting NMDA receptor and down-regulating nNOS protein expression; during the reperfusion, K-1024 has a satisfactory protective effect on spinal cord function, structure and biological activity of nerve cells.
The aortic dissection (AD) carries high mortality which increases by 1%-2% per hour after onset in untreated patients. Fifty percent of patients will die in 48 hours, and 70%-80% patients will die in 2 weeks without treatment. Moreover, acute AD during pregnancy is a rare and much catastrophic disease with high lethality for the mother and fetus simultaneously. At present, AD is so rare that most articles are mainly small cohort studies and case reports. Therefore, we reviewed literatures in order to provide clinical reference for the comprehensive treatment of AD.
Objective To summarize our experience and the early and midterm outcomes of stented elephant trunk procedure for right-sided aortic arch (RAA) with Kommerell's diverticulum (KD). Methods From April 2013 to July 2020, patients with RAA and KD who underwent stented elephant trunk procedure at our center were collected. Surgery was performed under moderate hypothermic circulatory arrest combined with selective antegrade cerebral perfusion via median sternotomy. Results A total of 8 patients were included, including 7 males and 1 female with a mean age of 51.88±9.61 years. All patients had an aneurysmal KD and aberrant left subclavian artery. Preoperative comorbidities included acute Stanford type B aortic dissection in 1 patient, aortic arch pseudoaneurysm in 1 patient, acute type B intramural hematoma in 2 patients, and coronary artery disease in 1 patient. Concomitant procedures included reconstruction of the left subclavian artery in all patients and coronary artery bypass grafting in 1 patient. The mean time of operation, cardiopulmonary bypass, aortic cross-clamping, and selective cerebral perfusion was 6.25±1.16 h, 157.75±40.07 min, 77.75±33.10 min, and 28.50±5.55 min, respectively. No intraoperative death occurred. There was 1 in-hospital death. Follow-up was completed in all patients with a mean period of 3.58±2.08 years. No late death occurred. A persistent anastomotic leak of the proximal arch was detected in 1 patient, but reintervention was not performed because neither aortic dilatation nor symptoms of tracheal and esophageal compression were observed during the follow-up. The remaining 6 patients showed positive aortic remodeling with complete thrombosis of the aneurysmal KD, and neither aortic event nor tracheal and esophageal compression occurred. Conclusion Stented elephant trunk procedure is a safe and feasible technique for selected patients with RAA and KD, which can achieve favorable early and midterm outcomes.