OBJECTIVE To determine the role of endogenous carbon monoxide(CO) in oxidant-mediated organ injury following limb ischemia-reperfusion (I/R) in rats. METHODS: Sixty-four SD rats were divided into 4 groups: Sham group, Sham + zinc protoporphyrin (ZnPP, an inhibitor of heme oxygenase activity), 2-hour ischemia followed by 4-hour reperfusion (I/R) group and I/R + ZnPP group. Carboxyhemoglobin (COHb) level in the artery blood, malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in the lung, heart, liver and kidney were detected. The 24-hour survival rate of rats was studied. RESULTS: Compared with the sham group, the COHb level and MDA content significantly increased, while the SOD activity and the survival rate significantly decreased in I/R group (P lt; 0.05). Compared with the I/R group, MDA content significantly increased, while the SOD activity, the 24-hour survival rate and COHb level significantly decreased in I/R + ZnPP group (P lt; 0.05, respectively). CONCLUSION: Limb I/R could lead to the oxidant-mediated multiple organ injury accompanied by the increase of CO level which play an important role in the defense against I/R-induced remote multiple organ injury in rats.
Limb motor dysfunction is the most common sequela of stroke. Its recovery cycle is long and difficult, which has an important impact on the physiology and psychology of patients. Therefore, the recovery of limb motor function after stroke has become the focus and difficulty of current rehabilitation. Brain-limb coordinate regulation technology is a rehabilitation strategy that effectively promotes the recovery of limb motor function and brain function through the organic combination of rehabilitation technology with limbs as target organs and brain as target organs. Based on the brain-limb coordinate regulation technology, this paper will systematically elaborate its theory and application through literature review, and then provide a more reasonable and effective choice for the treatment of limb motor dysfunction in stroke patients.
Objective To investigate the surgical characteristics and preliminary effectiveness of Orthofix unilateral external fixator in the treatment of musculoskeletal tumors. Methods Twenty-two patients received Orthofix unilateral external fixator treatment for bone defect after tumor excision or complications after limb salvage surgery between June 2011 and March 2016. There were 11 males and 11 females with a median age of 23.5 years (range, 4-57 years). The bone defect or limb length discrepancy after tumor resection was at proximal femur in 6 cases, distal femur in 8 cases, diaphysis of femur in 3 cases, proximal tibia in 2 cases, and diaphysis of tibia in 3 cases. The external fixation was used for temporary fixation after reconstruction of bone defect in 10 cases [the length of bone defect was 6-19 cm (mean, 12.3 cm); using vascularized fibular graft in 2 cases, allograft bone and free fibular graft in 2 cases, allograft bone and autogenous bone graft in 5 cases, allograft bone reconstruction in 1 case]; bone distraction lengthening for limb length discrepancy in 5 cases [the length of shortening was 6.5-8.5 cm (mean, 7.5 cm)]; temporary fixation after open biopsy in 3 cases; bone transportation over locking plate in 1 case (the length of bone defect was 7.5 cm); fixation for preoperatively pathology fracture in 1 case; and joint distraction for dislocation after tumor ablation in 2 cases. Results All the patients were followed up 12-72 months (mean, 36 months). In 10 patients with bone defect reconstruction, the wearing external fixator time was 3-8 months (mean, 4.8 months); all got bone union with the healing time of 3-16 months (mean, 6.4 months); the Musculoskeletal Tumor Society 93 (MSTS 93) score was 73.3-93.3 (mean, 87.2); and no complication occurred during wearing external fixator. In 5 patients with bone distraction lengthening for limb length discrepancy, the wearing external fixator time was 7-15 months; 2 patients had axial deviation during distraction and2 had greenstick fracture after apparatus removal; pin site infection was observed in 2 cases with grade 1 and 1 case with grade 2 according to Checketts-Otterburn classification system; the MSTS 93 score was 80.0-96.7 (mean, 89.2). The remaining patients had no complications, the knee and ankle joint movement was normal. Conclusion Orthofix unilateral external fixator can be used in fixation for complex bone defect after tumor resection and to correct limb length discrepancy after limb salvage surgery.
ObjectiveTo explore the relationship between the oxygen partial pressure of mice hindlimb muscles with normal blood supply or ischemia and expression of HIF-1αprotein, and to provide a theoretical basis for the study of angiogenesis in vitro hypoxia. MethodsMice hind limb ischemia model were established, tissue oxygen tension of gastrocnemius muscle and bone marrow were measured by micro electrode at different time points of ischemia (24 hours, 1 week, 2 weeks, 3 weeks, and unoperated as control). Protein level of hypoxia inducible factor-1αand histological examination were performed on gastrocnemius muscle as well. ResultsThe oxygen tension baselines of gastrocnemius muscle and femoral bone marrow was (47.78±4.37) mm Hg and (21±3.40) mm Hg, respectively. Muscle oxygen tension decreased significantly at all time points after modeling (P < 0.05), and reached lowest level in 1 week of ischemia. The inflammatory reaction was most serious and HIF-1αprotein reached highest level at the same time point. With the extension of ischemic time, the tissue oxygen tension recovered while HIF-1αlevel was down-regulated, however, There was no statistical correlation(r=-0.86, P > 0.05). Oxygen tension in bone marrow didn't show any significant change at all time points. ConclusionsThe expression level of HIF-1αprotein in ischemic tissue can reflect the degree of ischemic limb. The concept that physiological oxygen level differs in different tissue is highlighted, and may provide basis for ex vivo hypoxic research.
ObjectiveTo evaluate the treatment results of Ilizarov microcirculation reconstruction technique for chronic wounds in the post-traumatic ischemia limbs.MethodsBetween January 2016 and July 2019, 7 cases of chronic wounds in the post-traumatic ischemia limbs were treated. There were 5 males and 2 females, with an average age of 42.4 years (range, 29-66 years). The duration of the wound ranged from 1 month to 2 years (mean, 7.7 months). The wounds located in the leg (3 cases) or in the foot and ankle (4 cases). The wound sizes ranged from 4.0 cm×2.2 cm to 12.0 cm×7.1 cm. There were 1 case of tibial varus, 3 cases of equinovarus, 1 case of scleroderma, and 2 cases of Volkmann’s ischemic contracture. After debridement, external fixators were used for tibial transverse transport, or correction of tibial varus and correction of equinovarus.ResultsAll patients were followed up 8-20 months, with an average of 13 months. The infection of wound surface was all controlled in 7 cases and the granulation tissue grew well; the wound surface healed directly in 5 cases and healed after skin grafting in 2 cases, and the wound healing time was 1-3 months (mean, 1.7 months). During the follow-up, there was no recurrence of the wound. Six cases of limb deformity were corrected.ConclusionFor the chronic wounds in the post-traumatic ischemia limbs, Ilizarov microcirculation reconstruction technique can effectively improve local circulation and facilitate the fresh granule growth and wound healing.
Objective To investigate the application of abdominal aorta and bilateral abdominal perineal artery ligation in a hindlimb ischemia model of rats for research. Methods According to the random digits table, 38 SD rats were divided into 3 groups randomly, sham operation group (SO group, n=12), abdominal aorta ligation group (AAL group, n=12) and abdominal aorta and bilateral abdominal perineal artery ligation group (AAL+BAPA group, n=14). Rats were anesthetized by 6 mg/100 g ketamine via intraperitoneal injection. Blood vessels were ligated via laparotomy according to different procedures. Movement and pale skin color of rat’s hindlimb were observed on 2 and 4 weeks after operation, meanwhile venous blood from unilateral iliac vein was obtained for blood gas analysis and hindlimb skeletal muscle for HE stain. Results Two rats were dead during 3 d after operation in AAL+BAPA group, other rats survived. Rats in SO group had no obviously abnormal appearance. AAL group and AAL+BAPA group immediately presented hindlimbs pale, lower skin temperature, hypofrontality of limb motion after procedure. Symptoms above mentioned had improved gradually after 2 weeks and completely recuperated 4 weeks after operation in AAL group. Ischemia symptoms were still remained obviously such as cold, dried and thin on the 4th weekend in AAL+BAPA group. Each group had no hindlimbs necrosis. Two weeks after operation, pale limbs and muscle strength in AAL+BAPA group were more severe than those of SO group (Plt;0.05); Pale limbs was still worse than that of AAL group on 4 weeks after operation (Plt;0.05). There were no significant differences on different time in each group (Pgt;0.05). Venous blood partial pressure of oxygen of AAL+PABA group was significantly lower than that of the other two groups on 2 and 4 weeks after operation (Plt;0.05). Normal striated muscle structure was presented in SO group pathologically. AAL group revealed coloretur unevenness, swelling and distension, muscle cellular transverse striation elimination, skeletal muscle cell nucleolus deeply stained on the 2nd weekend and no difference with the SO group on the 4th weekend. AAL+BAPA group presented skeletal muscles decoration unevenness, cells swelling and distension, muscle cellular transverse striation elimination, skeletal muscle cell nucleolus stained deeply and intensively, intercellular space widening until the 4th weekend， but no obviously necrocytosis. Conclusion The method of ligating abdominal aorta and bilateral abdominal perineal artery can make a stable SD rat model of hindlimb ischemia
Objective To review the studies on vascular endothelium growth factor (VEGF) gene therapy for patients with chronic critical limb ischemia. Methods Advance in molecular biology of VEGF, mechanism of new vessel formation induced by VEGF and achievement of improving blood flow in patients with critical limb ischemia due to VEGF expressed by gene transfer in recent years has been reviewed in this article. Results Preclinical studies showed that VEGF can stimulate the development of collateral arteries in animals with limb ischemia, a concept called “therapeutic angiogenesis”, clinical results demonstrated that VEGF expressed by gene transfer can promote new vessel formation in patients with critical limb ischemia and improve significantly the prognosis for them.Conclusion VEGF gene transfer provide a novel treatment strategy for patients with critical limb ischemia, who neither had favorable response to phamarcological treatment nor were suitable for surgical reconstruction or revascularization.