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Effect of the free radical scavenger MCI-186 on spinal cord reperfusion after transient ischemia in the rabbit 总被引:4,自引:0,他引:4
Kenichi Hashizume Toshihiko Ueda Hideyuki Shimizu Atsuo Mori Ryohei Yozu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(8):426-433
Objective: Paraplegia remains a serious complication of aortic operations. The production of free radicals during reperfusion
after transient ischemia is believed to induce secondary spinal neuronal injury, resulting in paraplegia. The aim of the present
study was to clarify the protective effect and method of administration of antioxidants on the neurological and histological
outcome in the animal model for reperfusion injury after transient spinal cord ischemia. Methods: New Zealand white rabbits underwent surgical exposure of the abdominal aorta that was clamped for 15 minutes to achieve spinal
cord ischemia. Group A animals received two 10 mg/kg doses of 3-methyl-l-phenyl-2-pyrazolin-5-one (MCI-186) at the time of
release of the aortic clamp and 30 minutes later. In group B, MCI-186, 5 mg/kg, was given three times, at the time of aorta
clamp release, 30 minutes and 12 hours later. In group C (control group), one dose of vehicle was administered. Neurological
status was assessed using modified Tarlov’s score until 168 hours after operation. Spinal cord sections were examined microscopically
to determine the extent of ischemic neuronal damage. Results: Groups A and B animals had better neurological function than group C (p(0.001). In contrast, group C animals exhibited paraplegia or paraparesis with marked neuronal necrosis. The number of surviving
neurons within examined sections of the spinal cord was significantly greater in group B than in group C (p(0.001). Conclusion: In a 15-minute ischemia-reperfusion model using rabbits, systemic repetitious administration of MCI-186, a free radical scavenger,
was found to have a protective effect on the spinal cord neurons both neurologically and histologically. We postulate that
the drug minimizes the delayed neuronal cell death for reperfusion injury after transient ischemia by reducing the free radical
molecules. Moreover, it was thought that we could protect delayed neuronal cell death more effectively by administering MCI-18612
hours later. 相似文献
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Treatment strategy for synchronous metastases of colorectal cancer: is hepatic resection after an observation interval appropriate? 总被引:1,自引:1,他引:0
Yasuhiro Shimizu Kenzo Yasui Tsuyoshi Sano Takashi Hirai Yukihide Kanemitsu Koji Komori Tomoyuki Kato 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(5):535-538
Background In cases of synchronous colorectal hepatic metastases, the primary colorectal cancer strongly influences on the metastases.
Our treatment policy has been to conduct hepatic resection for the metastases at an interval of 3 months after colorectal
resection. We examined the appropriateness of interval hepatic resection for synchronous hepatic metastasis.
Materials and methods The subjects were 164 patients who underwent resection of hepatic metastasis of colorectal cancer (synchronous, 70 patients;
metachronous, 94 patients). Background factors for hepatic metastasis and postoperative results were compared for synchronous
and metachronous cases.
Results The cumulative survival rate for 164 patients at 3, 5, and 10 years postoperatively was 71.9%, 51.8%, and 36.6%, and the post-resection
recurrence rate in remnant livers was 26.8%. Interval resection for synchronous hepatic metastases was conducted in 49 cases
after a mean interval of 131 days. No difference was seen in postoperative outcome between synchronous and metachronous cases.
Conclusion The outcome was similarly favorable in cases of synchronous hepatic metastasis and in cases of metachronous metastasis. Delaying
resection allows accurate understanding of the number and location of hepatic metastases, and is beneficial in determining
candidates for surgery and in selecting surgical procedure. 相似文献
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Koichiro Ueki Yukari Hashiba Kohei Marukawa Kan Yoshida Chika Shimizu Kiyomasa Nakagawa Etsuhide Yamamoto 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(1):38-43
OBJECTIVE: To compare postoperative maxillary stability following Le Fort I osteotomy for the correction of occlusal cant as compared with conventional Le Fort I osteotomy for maxillary advancement. STUDY DESIGN: The subjects were 40 Japanese adults with jaw deformities. Of these, 20 underwent a Le Fort I osteotomy and intraoral vertical ramus osteotomy (IVRO) to correct asymmetric skeletal morphology and inclined occlusal cant. The other 20 patients underwent a Le Fort I osteotomy and sagittal split ramus osteotomy (SSRO) to advance the maxilla. Lateral and posteroanterior cephalograms were taken postoperatively and assessed statistically. Thereafter, the 2 groups were followed for time-course changes. RESULTS: There was no significant difference between the 2 groups with regard to time-course changes during the immediate postoperative period. CONCLUSION: This suggests that maxillary stability after Le Fort I osteotomy for cant correction does not differ from that after Le Fort I osteotomy for maxillary advancement. 相似文献
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Yuji Maruyama Shigeo Yamauchi Hidetsugu Ogasawara Hajime Imura Masami Ochi Kazuo Shimizu 《Annals of thoracic and cardiovascular surgery》2006,12(1):60-62
Surgical treatment for subacute pulmonary arterial thromboembolism has previously been considered to be inappropriate. We undertook a pulmonary arterial thrombectomy and removal of a floating right heart thrombus in a patient who had been symptomatic for over a month. The pulmonary arterial pressure, which had been equal to the systemic pressure preoperatively, decreased gradually and almost normalized one month postoperatively. Pulmonary perfusion scintigraphy revealed a dramatic improvement and the patient returned to normal life activities. 相似文献