Advances in extracellular vesicle-based combination therapies for spinal cord injury

Spinal cord injury is a severe insult to the central nervous system that causes persisting neurological deficits.The currently available treatments involve surgical,medical,and rehabilitative strategies.However,none of these techniques can markedly reverse neurological deficits.Recently,extracellular vesicles from various cell sources have been applied to different models of spinal cord injury,thereby generating new cell-free therapies for the treatment of spinal cord injury.However,the use of extracellular vesicles alone is still associated with some notable shortcomings,such as their uncertainty in targeting damaged spinal cord tissues and inability to provide structural support to damaged axons.Therefore,this paper reviews the latest combined strategies for the use of extracellular vesicle-based technology for spinal cord injury,including the combination of extracellular vesicles with nanoparticles,exogenous drugs and/or biological scaffold materials,which facilitate the targeting ability of extracellular vesicles and the combinatorial effects with extracellular vesicles.We also highlight issues relating to the clinical transformation of these extracellular vesicle-based combination strategies for the treatment of spinal cord injury.

Poor awareness of preventing aspirin-induced gastrointestinal injury with combined protective medications

AIM:To investigate prescribing pattern in low-dose aspirin users and physician awareness of preventing aspirin-induced gastrointestinal(GI) injury with combined protective medications.METHODS:A retrospective drug utilization study was conducted in the 2nd Affiliated Hospital,School of Medicine,Zhejiang University.The hospital has 2300 beds and 2.5 million outpatient visits annually.Data mining was performed on all aspirin prescriptions for outpatients and emergency patients admitted in 2011.Concomitant use of proton-pump inhibitors(PPIs),histamine 2-receptor antagonists(H2RA) and mucoprotective drugs(MPs) were analyzed.A defined daily dose(DDD) methodology was applied to each MP.A further investigation was performed in aspirin users on combination use of GI injurious medicines [non-steoid anti-inflammatory drugs(NSAIDs),corticosteroids and clopidogrel and warfarin] or intestinal protective drugs(misoprostol,rebamipide,teprenone and gefarnate).Data of major bleeding episodes were derived from medical records and adverse drug reaction monitoring records.The annual incidence of major GI bleeding due to low-dose aspirin was estimated for outpatients.RESULTS:Prescriptions for aspirin users receiving PPIs,H2RA and MPs(n = 1039) accounted for only 3.46% of total aspirin prescriptions(n = 30 015).The ratios of coadministration of aspirin/PPI,aspirin/H2RA,aspirin/MP and aspirin/PPI/MP to the total aspirin prescriptions were 2.82%,0.12%,0.40% and 0.12%,respectively.No statistically significant difference was observed in age between patients not receiving any GI protective medications and patients receiving PPIs,H2RA or MPs.The combined medication of aspirin and PPI was used more frequently than that of aspirin and MPs(2.82% vs 0.40%,P < 0.05) and aspirin/H2RA(2.82% vs 0.12%,P < 0.05).The values of DDDs of MPs in descending order were as follows:gefarnate,hydrotalcite > teprenone > sucralfate oral suspension > L-glutamine and sodium gualenate granules > rebamipide > sucralfate chewable tablets.The ratio of MP plus aspirin prescriptions to the total MP prescriptions was as follows:rebamipide(0.47%),teprenone(0.91%),L-glutamine and sodium gualenate granules(0.92%),gefarnate(0.31%),hydrotalcite(1.00%) and sucralfate oral suspension(0.13%).Percentages of prescriptions containing aspirin and intestinal protective drugs among the total aspirin prescriptions were:rebamipide(0.010%),PPI/rebamipide(0.027%),teprenone(0.11%),PPI/teprenone(0.037%),gefarnate(0.017%),and PPI/gefarnate(0.013%).No prescriptions were found containing coadministration of aspirin and other NSAIDs.Among the 3196 prescriptions containing aspirin/clopidogrel,3088(96.6%) prescriptions did not contain any GI protective medicines.Of the 389 prescriptions containing aspirin/corticosteroids,236(60.7%) contained no GI protective medicines.None of the prescriptions using aspirin/warfarin(n = 22) contained GI protective medicines.Thirty-five patients were admitted to this hospital in 2011 because of acute hemorrhage of upper digestive tract induced by low-dose aspirin.The annual incidence rates of major GI bleeding were estimated at 0.25% for outpatients taking aspirin and 0.5% for outpatients taking aspirin/warfarin,respectively.CONCLUSION:The prescribing pattern of low-dose aspirin revealed a poor awareness of preventing GI injury with combined protective medications.Actions should be taken to address this issue.

THE EFFECT OF SKIN GRAFTING AT DIFFERENT TIME POST BLOOD TRANSFUSION AND BONE MARROW TRANSPLANTATION ON RATS COMBINED RADIATION-BURN INJURY

After the rats were inflicted with 8 Gy total body gamma ray irradiation and 15 % total body surface area (TBSA) full thickness burn injury, they were treated with blood transfusion (BT) and bone marrow transplantation (BMT). Then the survival of allografts grafted on the escharectomized burn wounds in the 24, 48 and 72 h postinjury was observed. It was found that when the burn wounds were closed with allo- grafts in the 24h postinjury, there were an early elevation of leucocytes, the appearance of the donor’s cells and a significantly higher survival rate of the rats on the 30 day postinjury. The allografts could survive longer and wounds showed no signs of infection and healed quicker. When the allografts were grafted in the 48 h or 72 h postinjury, only harmful effects to hasten the death of rats were observed.

Update in combined musculoskeletal and vascular injuries of the extremities

Combined musculoskeletal and vascular injuries of the extremities are conditions in which a multidisciplinary approach is a sine qua non to ensure life initially and limb viability secondarily.Vascular injuries as part of musculoskeletal trauma are usually the result of the release of a high energy load in the wound site so that the prognosis is determined by the degree of soft-tissue damage,duration of limb ischemia,patient’s medical status and presence of associated injuries.The management of these injuries is challenging and requires a specific algorithm of action,because they are usually characterized by increased morbidity,amputation rate,infection,neurological and functional deficits,and they could be life threatening.Although vascular injuries are rare and occur either isolated or in the context of major combined musculoskeletal trauma,the high index of suspicion,imaging control,and timely referral of the patient to organized trauma centers ensure the best functional outcome of the extremity in such challenging cases.Even after a successful initial treatment of a combined trauma pattern,long-term follow-up is crucial to prevent and detect early possible complications.The purpose of this manuscript is to provide an update on diagnosis and treatment of combined musculoskeletal and vascular injuries of the extremities,from an orthopedic point of view.

Abnormal calcium transport ofmyocardial mitochondria during the early stage of combined radiation－burn injury in rats

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Effectiveness and postoperative rehabilitation of one-stage combined anterior-posterior surgery for severe thoracolumbar fractures with spinal cord injury

BACKGROUND Thoracolumbar fractures are generally combined with spinal cord injury to varying degrees,which may cause deterioration of the patients’condition and increase the difficulty of clinical treatment.At present,anterior or combined anterior-posterior surgery is preferred for severe thoracolumbar fractures.AIM To investigate the effectiveness and postoperative rehabilitation of one-stage combined anterior-posterior surgery for severe thoracolumbar fractures with spinal cord injury.METHODS One-hundred-and-twenty patients who received surgery for severe thoracolumbar fractures with spinal cord injury at our hospital from February 2018 to February 2020 were randomly enrolled.They were randomly divided into group 1(one-stage combined anterior-posterior surgery,n=60)and group 2(onestage anterior-approach surgery,n=60).Treatment efficacy was compared between the two groups.RESULTS Blood loss was greater and the operation time was longer in group 1 than in group 2,and the differences were statistically significant(P<0.05).Incision length,intraoperative X-rays,and length of hospital stay were not significantly different between the two groups(P>0.05).Preoperative function of the affected vertebrae was not significantly different between the two groups(P>0.05).In each group,the patients showed significant improvement after surgery.The anterior vertebral height ratio and the posterior vertebral height ratio in group 1 after surgery were significantly higher than those in group 2.The Cobb angle after surgery was significantly lower in group 1 than in group 2(P<0.05).The canal-occupying ratio of the affected vertebrae was not significantly different between the two groups(P>0.05).Before surgery,there was no significant difference in the quality of life scores between the two groups(P>0.05).The above indicators were significantly improved after surgery compared with before surgery in each group.In addition,these indicators were markedly better in group 1 than in group 2 after surgery(P<0.05 for each).CONCLUSION One-stage combined anterior-posterior surgery effectively improves the function of the affected vertebrae and the life quality of patients with severe thoracolumbar fractures and spinal cord injury.This surgical approach is worthy of popularization in clinical use.

EFFECTS OF BLOOD TRANSFUSION ON BONE MARROW TRANSPLANTATION IN RATS WITH RADIATION-BURN COMBINED INJURY

The effects of pre-irradiation blood transfusion(BT)on survival rateof radiation-burn combinedly injured rats receiving bone marrow transplantation(BMT) were studied. It was found that after 9-11 Gy of radiation was given, the 90-daysurvival rate of the rats receiving BT(72%) and BMT was significantly higher than thatof those receiving BMT only(42%)(P<0.01).In those rats surviving over 100 days,cells of donor type could be found. In the first 30 days of surviving, the number of Tcells was significantly higher in the BMT alone group than in the group of BMT plusBT, but no difference In restoration of B cell was revealed. The findings suggest that BTcould promote the recipient's tolerance to BMT. The effects of BT on BMT are similarto those on skin grafting.

IN-1 combined with neurotrophin-3 for axonal growth-related gene expression after spinal cord injury

A spinal cord hemisection injury model was established in rats. Treatment with IN-1 and/or neurotrophin-3 was found to regulate the expression of growth-associated protein 43, nerve growth factor, and basic fibroblast growth factor genes in the injured spinal cord tissues; transcript levels were first increased and then decreased. Expression levels reached a peak at days 7 （growth-associated protein 43） or 14 （nerve growth factor and basic fibroblast growth factor） following spinal cord injury. Combined treatment with neurotrophin-3 and IN-1 achieved the most apparent effect on the expression and recovery of motor function. These findings confirm that combined therapy with neurotrophin-3 and IN-1 can increase expression of growth factors in the injured spinal cord tissues and promote the axonal reaeneration.

CHANGES OF IMMUNE FUNCTIONS AFTER RADIATION，BURNS AND COMBINED RADIATION－BURN INJURY IN RATS

The changes of several immune functions were observed in rats after they were inflicted with 6 Gy gamma rays irradiation, 15% TBSA full thickness brun and the combination of the 2 injuries. It was found that the functions of thymocytes and splenocytes suffered the most severe suppression in the 24th to 72nd hour after radiation injury and began to recover on the 7th day. In the rats with burn injury, the suppression on thymocytes and splenocytes were significantly less severe than that after radiation and recovered more rapidly. The effects of combined radiation-burn injury showed several characteristics. The suppression on the thymocytes was more severe with slower recovery as compared with that after single radiation injury only. The suppression on the splenocytes as a whole was similar to that after single radiation injury , but in the early stage after combined injury, the suppression was far more severe than that after radiation Escharectomy and skin grafting on the burn wounds on the lst day after combined injury could accelerate the recovery on both the thymocytes and splenocytes. Our findings indicated that the severity of the suppression on the immune functions due to combined radiation-burn injury might depend on the size of the burn wounds.

Clinical features of multiple trauma patients combined with spine and spinal cord injuries

Objective To analyze the clinical features of the multiple trauma patients combined with spine and spinal cord injuries.Methods A retrospective study was performed in143multiple trauma patients combined with spine and spinal

Comparison of the Efficacy of Standard Decompressive Craniectomy Combined with Cerebrospinal Fluid Circulation Reconstruction in the Treatment of Severe Craniocerebral Injury

Objective:To observe and discuss the clinical effect of standard decompressive craniectomy combined with cerebrospinal fluid circulation reconstruction in the treatment of severe craniocerebral injury.Methods:Seventy patients who underwent surgery in our hospital were selected as subjects for this study.The time was from August 2016 to August 2018,and patients were divided into experimental group(35 cases)and control group(35 cases)according to the random number table method.The control group was treated with a single standard decompressive craniectomy according to clinical symptoms.The experimental group was treated with standard decompressive craniectomy combined with cerebrospinal fluid circulation reconstruction.The surgical treatment effect,GCS(Glasgow Coma Scale)score and operation time were compared between the two groups.Results:After comparison,the surgical treatment effect of the experimental group was higher than that of the control group and there was a significant difference between the two groups(P<0.05).The GCS score and operation time of the experimental group were also better than of the control group and there was a significant difference the two groups(P<0.05).Conclusion:The use of standard decompressive craniectomy combined with cerebrospinal fluid circulation reconstruction in the treatment of severe craniocerebral injury is more effective and worthy of widespread promotion and application.

Expression of transforming growth factor-β in local bony callus in traumatic brain injury combined with extremity fracture in rats

Objective To investigate gene expression of transforming growth factor-β(TGF-β)in local bony callus in tracumatic brain in jury combined with extremity long bone fracture in rats.Methods Eighty male SD rats were randomized into 2 even

Dynamic changes of myocardial nitric oxide formation and cGMP content in the early stage after radiation, burn and combined radiation-burninjuries in rats

Nitric oxide formation and cyclic GMP level in the myocardium were studied in the early stage after radiation, bum andcombined radiation-bum injuries in rats. Nitric oxide synthase (NOS) activity was measured in the cytosol of the left ventricularwall. In the controls, the cytosol was found to contain mainly Ca2+ -dependent NOS (cNOS) and a small amount of Ca2+ -inden-pendent NOS (iNOS). After burn and combined radiation-burn injuries, a marked increase of iNOS activity with a peak in the 8thhour postinjury was found but the myocardial cNOS activity declined obviously. Parallel to iNOS activity increase, there was a significant increase of myocardial production of NO and cGMP. The combined effcts of radiation and burn injuries on the rats weremore severe than those of burn injury alone. All the changes could be prevented by the administration of dexamethasone. No obvious changes were observed in the rats after radiation injury alone. Since the increase of cGMP level in the heart is associated withreduced contractility, it is possible that the increased production of NO stimulated by iNOS accounts at least partially, for the depression of myocardial contractility after bum and combined radiation burn injury.

Combination of mild therapeutic hypothermia and adipose-derived stem cells for ischemic brain injury

Mild therapeutic hypothermia has been shown to mitigate cerebral ischemia, reduce cerebral edema, and improve the prognosis of patients with cerebral ischemia. Adipose-derived stem cell-based therapy can decrease neuronal death and infiltration of inflammatory cells, exerting a neuroprotective effect. We hypothesized that the combination of mild therapeutic hypothermia and adipose-derived stem cells would be neuroprotective for treatment of stroke. A rat model of transient middle cerebral artery occlusion was established using the nylon monofilament method. Mild therapeutic hypothermia（33°C） was induced after 2 hours of ischemia. Adipose-derived stem cells were administered through the femoral vein during reperfusion. The severity of neurological dysfunction was measured by a modified Neurological Severity Score Scaling System. The area of the infarct lesion was determined by 2,3,5-triphenyltetrazolium chloride staining. Apoptotic neurons were detected by terminal deoxynucleotidyl transferase-mediated d UTP-biotin nick end labeling（TUNEL） staining. The regeneration of microvessels and changes in the glial scar were detected by immunofluorescence staining. The inflammatory responses after ischemic brain injury were evaluated by in situ staining using markers of inflammatory cells. The expression of inflammatory cytokines was measured by reverse transcription-polymerase chain reaction. Compared with mild therapeutic hypothermia or adipose-derived stem cell treatment alone, their combination substantially improved neurological deficits and decreased infarct size. They synergistically reduced the number of TUNEL-positive cells and glial fibrillary acidic protein expression, increased vascular endothelial growth factor levels, effectively reduced inflammatory cell infiltration and down-regulated the m RNA expression of the proinflammatory cytokines interleukin-1β, tumor necrosis factor-α and interleukin-6. Our findings indicate that combined treatment is a better approach for treating stroke compared with mild therapeutic hypothermia or adipose-derived stem cells alone.

Combined transplantation of GDAs^(BMP) and hr-decorin in spinal cord contusion repair

Following spinal cord injury, astrocyte proliferation and scar formation are the main factors inhibiting the regeneration and growth of spinal cord axons. Recombinant decorin suppresses inflammatory reactions, inhibits glial scar formation, and promotes axonal growth. Rat models of T8 spinal cord contusion were created with the NYU impactor and these models were subjected to combined transplantation of bone morphogenetic protein-4-induced glial-restricted precursor-derived astro- cytes and human recombinant decorin transplantation. At 28 days after spinal cord contusion, dou- ble-immunofluorescent histochemistry revealed that combined transplantation inhibited the early in- flammatory response in injured rats. Furthermore, brain-derived neurotrophic factor, which was se- creted by transplanted cells, protected injured axons. The combined transplantation promoted ax- onal regeneration and growth of injured motor and sensory neurons by inhibiting astrocyte prolif- eration and glial scar formation, with astrocytes forming a linear arrangement in the contused spinal cord, thus providing axonal regeneration channels.

Tall gastrodis tuber combined with antiepileptic drugs repairs abnormal perfusion foci in focal epilepsy

One hundred patients with focal epilepsy were recruited for the present study and their seizures controlled with antiepileptic drugs. The patients then orally received a capsule of tall gastrodis tuber powder, a traditional Chinese drug, and underwent single photon emission computed tomography, long-term electroencephalogram, and CT/MRI. Blood drug levels were monitored throughout the study. Before treatment with tall gastrodis tuber, 35 of the 100 cases had abnormal CT/MRI scans; 79 cases had abnormal single photon emission computed tomography images; 86 cases had abnormal electroencephalogram; and a total of 146 abnormal perfusion foci were observed across the 100 subjects. After treatment, the number of patients with normal single photon emission computed tomography images increased by 12; normal electroencephalogram was observed in an additional 27 cases and the number of patients with epileptiform discharge decreased by 29 （34% of 86）; the total number of abnormal perfusion foci decreased by 52 （36%） and changes in abnormal loci were visible in 65 patients. These changes indicate that the administration of tall gastrodis tuber in combination with antiepileptic drugs repairs abnormal perfusion foci in patients with focal epilepsy Our results demonstrate that traditional Chinese drugs can repair abnormal perfusion foci and, as such, are a promising new pathway in the treatment of focal epilepsy.

Effects of a combination of Japanese Raisin Tree Seed and Flower of Lobed Kudzuvine against acute alcohol-induced liver injury in mice

Objective:The Flower of Lobed Kudzuvine[Pueraria lobata(Willd.)Ohwi;Gehua in Chinese;GH]and Japanese Raisin Tree Seed(Hovenia dulcis Thunnb.;Zhijuzi in Chinese;ZJZ)are herbs that have been used in China for the treatment of alcohol intoxication and liver diseases.We aimed to evaluate the hepatoprotective potential of a combination of these in mice with acute alcohol-induced liver injury,and to elucidate the mechanisms involved.Methods:Male ICR mice were randomly allocated to six groups:a control group,an alcohol-administered group,and groups that were administered alcohol and one of silibinin,the GH,the ZJZ or a GH-ZJZ combination(at a ratio of 2:1).Animals were orally administered 56%alcohol(Er Guo-tou white spirit,0.12 mL/10 g/d)for 10 days and at the end of this period,hepatic biochemical indicators,antioxidant parameters,alcohol metabolic enzymes,and histopathologic changes were evaluated.Moreover,the expression of the signaling molecules KEAP1,NRF2,and AQP9 were measured by qRT-PCR and western blotting.Results:Compared with the model group,GH-ZJZ(2:1)had lower serum ALT(12.15±0.39,P紏.003),AST(104.07±1.03,P紏.001),and ALP(148.09±2.55,P紏.010)activities,and lower TC(1.97±0.05,P紏.001)and TG(1.54±0.07,P?.002)concentrations.GH-ZJZ(2:1)also significantly increased the hepatic activities of SOD and GSH(4.24±0.25 and 1.57±0.06,respectively;both P<.01),reduced the ROS and MDA concentrations(97.50±3.00 and 2.39±0.19,respectively;both P<.01),and upregulated Nrf2 expression(P<.01).GH-ZJZ(2:1)significantly reduced the expression of KEAP1 and AQP9 in the liver,compared with alcohol-administered mice(P<.01).Importantly,the GH-ZJZ combination caused a more marked improvement in acute liver injury than GH or ZJZ alone.Conclusion:We have demonstrated protective effects of GH-ZJZ(2:1)against acute alcohol-induced hepatic injury,and shown that these effects may be associated with improvements in lipid and alcohol metabolism,antioxidant capacity,and lipid peroxidation.

辐射复合不同减压负荷暴露致大鼠急性损伤的效应及其可能的机制

目的观察特定辐射剂量复合减压暴露致大鼠损伤的效应及其可能的机制。方法81只雄性SD大鼠,随机分为空白对照组(n=9)、单纯辐射组(n=18)、辐射+低负荷减压组(n=18)、辐射+中负荷减压组(n=18)和辐射+高负荷减压组(n=18)。除空白对照组外,大鼠接受4Gy的60Coγ射线全身照射,然后进行快速上浮脱险实验,高气压暴露方案分别为在水下57m停留30min、45min或60min后(30±5)s内减至常压,单纯辐射组不进行高气压暴露。出舱后0.5h观察各组大鼠行为和死亡情况,分别于3h和72h取血(腹主动脉)和肺组织,分析肺湿/干重比(W/D)、肺组织病理及血清白细胞介素(IL)-1β、IL-6、肿瘤坏死因子-α(TNF-α)、超氧化物歧化酶(SOD)、丙二醛(MDA)、一氧化氮(NO)、细胞间黏附分子1(ICAM-1)和血栓素B2(TXB2)含量的变化。结果与空白对照组和单纯辐射组比较,辐射+低负荷减压组大鼠伤死率差异无统计学意义(P>0.05),辐射+中负荷减压组和辐射+高负荷减压组大鼠伤死率均明显增高(P<0.05)。与空白对照组比较,其他各组大鼠减压结束后3h肺W/D差异均无统计学意义(P>0.05),减压结束后72h肺W/D均升高(P<0.05)。HE染色结果显示,与空白对照组比较,单纯辐射组大鼠肺间质轻度水肿;辐射+低负荷减压组大鼠肺组织水肿明显,肺泡腔内可见少量红细胞渗出;辐射+中负荷减压组和辐射+高负荷减压组大鼠肺组织水肿、充血及炎性细胞浸润更为严重。与空白对照组和单纯辐射组比较,各辐射+减压组血清IL-1β、IL-6、TNF-α、MDA、NO、ICAM-1、TXB2水平均升高(P<0.05),SOD活性均降低(P<0.05);与辐射+低负荷减压组比较,辐射+中负荷减压组和辐射+高负荷减压组大鼠血清IL-1β、IL-6、MDA、ICAM-1、TXB2水平均增高(P<0.05),SOD活性均降低(P<0.05);除空白对照组外,与减压结束后3h比较,各组大鼠减压结束后72 h血清IL-1β、IL-6、TNF-α、MDA、NO、ICAM-1、TXB2水平均降低(P<0.05),SOD活性均增强(P<0.05)。结论高减压负荷可致辐照+高气压暴露的大鼠伤死率增高,辐射和减压复合损伤效应的潜在机制可能与炎症、免疫应激、氧化损伤、血管舒缩活性和凝血机制相关。

家庭成员之间身体侵害行为定罪相关因素研究——基于349份裁判文书的实证分析

公开的全部虐待罪和家庭成员之间身体侵害行为有关故意伤害罪的裁判文书共349份,有341个被告人的有效样本。总样本的双变量相关分析发现侵害行为的持续时间、次数与定罪均显著负相关,身份关系、使用工具情况、人体损伤程度则与定罪不相关。基于年龄的分组比较还发现若干组间差异。对相关分析的整体反思能够归纳四个裁判倾向,不同倾向的价值判断标准之间存在潜在冲突,而且缺乏规范性的裁判逻辑。应当准确把握虐待罪适用的刑事政策,充分认识到虐待罪是刑法特殊保护家庭成员人身权利的专门堵截性罪名。建议从四方面完善区分虐待罪和故意伤害罪的定罪规则,如单次侵害行为根据人体损伤结果区分两罪;两次或多次行为,直接致人轻伤及以上结果的单次行为构成故意伤害罪,其他符合“情节恶劣”的行为构成虐待罪。

大鼠密闭管道内爆炸烧冲复合伤及重要器官损伤的观察研究

目的采用密闭管道内气体爆炸方式,建立热辐射与冲击波复合致伤模型,探讨爆炸烧冲复合因素致大鼠重要器官伤情特点。方法8~10周龄雄性SD大鼠72只,体质量(200±10)g,随机分为对照组、轻度组、重度组。采用爆炸冲击波与热辐射致伤系统致大鼠不同程度损伤,并进行物理参数测试,伤后存活大鼠进行呼吸功能检测,24 h后解剖并检测血气、血液生化及血清炎症因子、肺损伤相关蛋白等指标,并观察肺组织及气管病理学形态变化情况。结果爆炸冲击波超压峰值范围为209~493 kPa,温度为152~258℃;轻度组死亡率为8.3%,重度组死亡率为53.1%;与对照组比较,伤后6 h内大鼠吸气时间(inspiratory time,Ti)、潮气量(Tidal Volume,TV)、松弛时间(relaxation time,Tr)增高(P<0.05),呼吸频率(respiratory rate,f)降低(P<0.05);伤后24 h二氧化碳分压(PaCO_(2))、碱剩余值(BE)、碳酸氢根(HCO_(3)^(-))值显著增高(P<0.05),氧分压(PaO_(2))显著降低(P<0.05);血清丙氨酸转氨酶(alanine transaminase,ALT)、天冬氨酸氨基转氨酶(aspartate aminotransferase,AST)、碱性磷酸酶(alkaline phosphatase,ALP)、总胆红素(total bilirubin,TBI)、总胆汁酸(total bile acid,TBA)水平均显著增高(P<0.05),白细胞介素-1β(interleukin-1β,IL-1β)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、IL-6水平均显著增高(P<0.01);伤后大鼠气管黏膜层有不同程度的出血灶及发炎;肺损伤发生率高且病理表现为点片状出血至整肺叶弥漫性出血,肺泡间隔断裂,间隔增厚,红细胞及炎性细胞浸润,血清肺损伤相关蛋白水平显著增高(P<0.05)。结论建立出高度模拟密闭管道内轻至重度爆炸烧冲复合伤、能够满足研究需要的大鼠模型;爆炸烧冲复合伤以肺损伤、呼吸功能障碍、肝脏损伤及继发性感染为主。