Effect of the interval between two shocks on ejecta formation from the grooved aluminum surface

This work focuses on the effect of the interval between two shocks on the ejecta formation from the grooved aluminum(Al_(1100))surface by using smoothed particle hydrodynamics numerical simulation.Two unsupported shocks are obtained by the plate-impact between sample and two flyers at interval,with a peak pressure of approximately 30 GPa for each shock.When the shock interval varies from 2.11 to 7.67 times the groove depth,the bubble velocity reduces to a constant,and the micro jetting factor R_(J) from spike to bubble exhibits a non-monotonic change that decreases initially and then increases.At a shock interval of 3.6 times the groove depth,micro jetting factor R_(J) from spike to bubble reaches its minimum value of approximately 0.6.While,the micro jetting factor R_(F) from spike to free surface decreases linearly at first,and stabilizes around 0.25 once the shock interval surpasses 4.18 times the groove depth.When the shock interval is less than 4.18 times the groove depth,the unloading wave generated by the breakout of the first shock wave is superimpose with the unloading part of the second shock wave to form a large tensile area.

STABILITY OF TRANSONIC SHOCKS TO THE EULER-POISSON SYSTEM WITH VARYING BACKGROUND CHARGES

This paper is devoted to studying the stability of transonic shock solutions to the Euler-Poisson system in a one-dimensional nozzle of finite length.The background charge in the Poisson equation is a piecewise constant function.The structural stability of the steady transonic shock solution is obtained by the monotonicity argument.Furthermore,this transonic shock is proved to be dynamically and exponentially stable with respect to small perturbations of the initial data.One of the crucial ingredients of the analysis is to establish the global well-posedness of a free boundary problem for a quasilinear second order equation with nonlinear boundary conditions.

High-Order DG Schemes with Subcell Limiting Strategies for Simulations of Shocks,Vortices and Sound Waves in Materials Science Problems

Shock waves,characterized by abrupt changes in pressure,temperature,and density,play a significant role in various materials science processes involving fluids.These high-energy phenomena are utilized across multiple fields and applications to achieve unique material properties and facilitate advanced manufacturing techniques.Accurate simulations of these phenomena require numerical schemes that can represent shock waves without spurious oscillations and simultaneously capture acoustic waves for a wide range of wavelength scales.This work suggests a high-order discontinuous Galerkin(DG)method with a finite volume(FV)subcell limiting strategies to achieve better subcell resolution and lower numerical diffusion properties.By switching to the FV discretization on an embedded sub-cell grid,the method displays advantages with respect to both DG accuracy and FV shock-capturing ability.The FV scheme utilizes a class of high-fidelity schemes that are built upon the boundary variation diminishing(BVD)reconstruction paradigm.The method is therefore able to resolve discontinuities and multi-scale structures on the subcell level,while preserving the favorable properties of the high-order DG scheme.We have tested the present DG method up to the 6th-order accuracy for both smooth and discontinuous noise problems.

长直坑道内爆炸冲击波相似规律研究

通过长直坑道内炸药爆炸后冲击波的超压峰值变化研究坑道内爆炸冲击波的相似规律。使用AUTODYN软件建立长直坑道仿真模型,采用映射方法将3.25 kg当量的球形TNT炸药在空气中的爆炸状态映射到长直坑道中,采用经典试验结果对模型进行验证。根据几何相似原理,通过改变坑道尺寸、坑道截面形状、炸点位置和炸药当量建立多组不同的模型,模拟计算得到坑道内爆炸冲击波的超压峰值,分析超压峰值的相似规律。结果表明,保持坑道截面积不变、改变截面形状及保持爆心距与炸药当量的比值不变、改变炸药当量,各模型计算得到的冲击波超压峰值具有相似规律。采用本文方法可对其他满足几何相似原理的坑道内爆炸冲击波参数进行预测,为地下空间设施的安全设计提供参考。

血小板激活因子拮抗剂WEB2086对小鼠腹腔巨噬细胞释放肿瘤坏死因子的影响(英文)

小鼠ip3%TG 4天后取其腹腔巨噬细胞,血小板激活因子拮抗剂WEB 2086对LPS诱导的巨噬细胞释放肿瘤坏死因子(TNF)有显著的抑制作用。时效研究表明,TNF的产生和WEB 2086的抑制作用从LPS刺激后4 h开始,持续到22 h,在16 h时达到高峰。本文还首次采用一种用放线菌素D和NaF处理的L-929细胞测定TNF的新方法,此法与另外3种生物测定方法进行比较的结果显示此法具有更敏感、方便的特点。

蝙蝠葛碱和粉防己碱对[~3H]WEB 2086与体外牛脑前动脉平滑肌细胞结合的影响(英文)

用标记的血小板活化因子拮抗剂[~3H]WEB 2086,在培养的牛脑前动脉平滑肌细胞上鉴定了血小板活化因子受体。结果表明在25℃时该细胞上存在两种与配基具有不同亲和力的受体结合位点,其中K_(d-1)=22.8±5.0 nmol·L^(-1),K_(d-2)=186+20.5 nmol·L^(-1);B_(max-1)=2.1±0.3 pmol/10~4细胞,B_(max-2)=12.1±1-5 pmol/10~6细胞。蝙蝠葛碱和粉防己碱均能抑制[~3H]WEB2086与上述细胞的结合。

血小板活化因子受体拮抗剂WEB2086抑制载脂蛋白E基因敲除鼠主动脉粥样硬化斑块内血管新生

目的 观察血小板活化因子受体拮抗剂WEB2 0 86对载脂蛋白E基因敲除鼠斑块内血管新生和斑块面积的影响。方法 8周龄雄性载脂蛋白E基因敲除鼠普通饲料喂养2 4周,然后随机分为对照组和WEB2 0 86组2组,每组18只。两组均普通饲料,对照组普通饮水,WEB2 0 86组则在普通饮水中加入血小板活化因子受体拮抗剂WEB2 0 86 (43mg/L)。继续喂养8周后,空腹18h采血,安乐死,取材。全自动生物化学分析仪检测血清脂质含量,CD31全层铺片检测斑块内毛细血管密度,含斑块的主动脉环置于matrigel中培养检测斑块新生毛细血管的能力,苏丹Ⅳ染色检测斑块面积。结果 WEB2 0 86对血清脂质无明显影响。WEB2 0 86明显抑制粥样斑块内毛细血管平均密度(34.6 %±10 .2 %比16 .1%±6 .7% ,P <0 .0 1)、明显抑制含斑块的主动脉环在matrigel中新生毛细血管(172 .3±4 0 .6比73.1±2 4 .9,P <0 .0 5 )、显著减小主动脉斑块面积(31.4 %±9.7%比17.5 %±6 .3% ,P <0 .0 1)。结论 WEB2 0 86对血脂无明显影响,但可抑制斑块内血管新生和减小斑块面积。

高原环境爆炸冲击波传播规律及计算模型研究

为研究高原地区的低温低压环境对冲击波传播特性的影响,在海拔1500,3000,4500 m环境下开展了TNT爆炸试验,并使用有限元软件对高原环境TNT的爆炸冲击波进行数值仿真计算,分析了不同海拔对冲击波传播特性的影响规律。对比了Sadovskyi,Kinney-Graham和Sachs修正公式的超压峰值和比冲量计算结果与试验结果,并采用Sachs修正中的温度修正项对Sadovskyi高原超压峰值公式进行了修正。研究结果表明:随着海拔的升高,冲击波的波阵面速度加快,到达时间提前,每升高1 km,冲击波超压峰值下降约2%~4%,比冲量下降约4%;对超压峰值进行修正时,3种修正公式均具有一定的准确性;对比冲量进行修正时,Kinney-Graham修正的比冲量值随比例距离增加呈线性降低,与试验结果吻合较差,庞春桥与Sachs的修正结果随比例距离增加呈指数降低;基于温度项修正的Sadovskyi高原冲击波超压峰值经验公式的平均误差减小了3.1%。该研究结果对于高海拔地区的弹药毁伤效能评估有参考意义。

膝骨关节炎疼痛领域热点与前沿的可视化分析

背景:疼痛是膝骨关节炎的主要症状,严重影响老年患者的生活质量。膝骨关节炎疼痛机制复杂,涉及多组织、多学科,需要可视化分析了解其主要内容与研究热点。目的:运用文献计量学可视化软件分析归纳膝骨关节炎疼痛领域的前沿内容和研究热点。方法:从Web of Science核心合集(Web of Science Core Collection,WoSCC)中检索2014-2024年膝骨关节炎疼痛领域的相关文献,运用Citespace、VOSviewer和Bibliometrix R-package三个可视化软件进行文献计量与可视化分析。结果与结论:①膝骨关节炎疼痛研究的发文量呈现逐年递增的趋势;②美国、中国、澳大利亚是该领域10年内发文量排名前三的国家;波士顿大学、悉尼大学、弗洛里达大学是发文量前三的科研机构;《OSTEOARTHRITIS AND CARTILAGE》是出版该领域文献最多的期刊,《PAIN》则是该领域被引次数最多的期刊;发文量最多的作者是Fillingim Roger B,该领域的核心作者之间已经建立了一些稳定的团队,但国际性合作尚有欠缺;③膝骨关节炎疼痛患者的日常管理(运动、心理、智能管理)、疼痛的炎症机制、蛋白组学、联合用药、中枢敏化和疼痛调节是膝骨关节炎疼痛研究的重点内容;人工智能辅助、体外冲击波疗法、射频消融术、神经冷冻术、关节腔内注射血液或细胞制剂可能是该领域的研究前沿。

Spontaneous Orientation Polarization of Anisotropic Equivalent Dipoles Harnessed by Entropy Engineering for Ultra‑Thin Electromagnetic Wave Absorber

The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engineering of conductive/dielectric genes.Electron migration modes within HEAs as manipulated by the electronegativity,valence electron configurations and molar proportions of constituent elements determine the steady state and efficiency of equivalent dipoles.Herein,enlightened by skin-like effect,a reformative carbothermal shock method using carbonized cellulose paper(CCP)as carbon supporter is used to preserve the oxygencontaining functional groups(O·)of carbonized cellulose fibers(CCF).Nucleation of HEAs and construction of emblematic shell-core CCF/HEAs heterointerfaces are inextricably linked to carbon metabolism induced by O·.Meanwhile,the electron migration mode of switchable electronrich sites promotes the orientation polarization of anisotropic equivalent dipoles.By virtue of the reinforcement strategy,CCP/HEAs composite prepared by 35%molar ratio of Mn element(CCP/HEAs-Mn_(2.15))achieves efficient electromagnetic wave(EMW)absorption of−51.35 dB at an ultra-thin thickness of 1.03 mm.The mechanisms of the resulting dielectric properties of HEAs-based EMW absorbing materials are elucidated by combining theoretical calculations with experimental characterizations,which provide theoretical bases and feasible strategies for the simulation and practical application of electromagnetic functional devices(e.g.,ultra-wideband bandpass filter).

高压氧可消除高强度间歇冲击微周期训练中的运动性疲劳

背景:高压氧作为新兴的疲劳消除手段之一,在体育领域中得到越来越多的重视和应用。高压氧干预对高强度间歇冲击微周期训练疲劳消除的研究较少。目的:探究高压氧干预对高强度间歇冲击微周期训练运动性疲劳消除效果的影响,并从血液生化指标和代谢组学方面进行相应机制研究。方法:在首都体育学院招募20名男性大学生,随机分为对照组(n=10)和高压氧组(n=10),均进行高强度间歇冲击微周期训练,为期2周,共12次,具体训练方案为先以50%HR_(max)的强度热身10 min,再以90%-95%HR_(max)强度蹬车4 min,重复5组,组间休息2.5 min,最后再进行50%HR_(max)强度蹬车30 min。对照组受试者训练后自然恢复,高压氧组受试者训练后进行高压氧恢复,每次干预60 min,压力为131.722 kPa。在试验前、试验中期、试验后1 d和试验后3 d采集血液分析生化指标及代谢组学指标,并进行主观感觉疲劳量表评分,其中氧化应激指标与疲劳监控指标进行Pearson相关性分析。结果与结论:①运动性疲劳指标变化:与训练前相比,对照组训练后血尿酸、肌酸激酶、白细胞介素6和主观感觉疲劳量表评分均有不同程度的上调,而高压氧组在高压氧干预后血尿酸、肌酸激酶、白细胞介素6和主观感觉疲劳量表评分变化不大;组间相比,对照组试验后1 d血尿酸、肌酸激酶和白细胞介素6水平显著高于高压氧组;②氧化应激指标变化:与训练前相比,对照组训练后超氧化物歧化酶活性降低、丙二醛水平升高,而高压氧组在高压氧干预后超氧化物歧化酶活性升高、丙二醛水平降低;③超氧化物歧化酶与血尿酸、白细胞介素6和主观感觉疲劳量表评分呈负相关;丙二醛与白细胞介素6和主观感觉疲劳量表评分呈正相关;④代谢组学指标变化:显著变化的代谢通路是花生四烯酸代谢和氧化磷酸化代谢,富集通路上差异代谢物质有花生四烯酸、前列腺素D2、白三烯D4等。结果表明,高强度间歇冲击微周期训练导致机体发生氧化应激,促进了运动性疲劳的产生;高压氧可以一定程度改善氧化应激水平,以及引起花生四烯酸代谢和氧化磷酸化代谢,从而减少氧化损伤,调节炎症反应,促进组织修复和运动性疲劳消除。

Septic shock due to cytomegalovirus colitis associated with rituximab use:A case report

BACKGROUND Cytomegalovirus(CMV)infections can cause significant morbidity and mortality in immunocompromised individuals.CMV targets dysfunctional lymphocytes.Chronic rituximab(RTX)therapy can cause B-lymphocyte dysfunction,increasing CMV risk.Rarely,CMV infections present with critical illness such as septic shock.CASE SUMMARY A 64-year-old African American woman presented with generalized weakness and non-bloody watery diarrhea of 4-6 weeks duration.She did not have nausea,vomiting or,abdominal pain.She had been on monthly RTX infusions for neuromyelitis optica.She was admitted for septic shock due to pancolitis.Blood investigations suggested pancytopenia and serology detected significantly elevated CMV DNA.Valganciclovir treatment led to disease resolution.CONCLUSION This case illustrates an extremely rare case of CMV colitis associated with RTX use presenting with septic shock.High suspicion for rare opportunistic infections is imperative in individuals with long-term RTX use.

Prognostic impact of hypernatremia for septic shock patients in the intensive care unit

BACKGROUND Hypernatremia represents a significant electrolyte imbalance associated with numerous adverse outcomes,particularly in cases of intensive care unit(ICU)-acquired hypernatremia(IAH).Nevertheless,its relevance in patients with septic shock remains uncertain.AIM To identify independent risk factors and their predictive efficacy for IAH to improve outcomes in patients with septic shock.METHODS In the present retrospective single-center study,a cohort of 157 septic shock patients with concurrent hypernatremia in the ICU at The First Affiliated Hospital of Soochow University,between August 1,2018,and May 31,2023,were analyzed.Patients were categorized based on the timing of hypernatremia occurrence into the IAH group(n=62),the non-IAH group(n=41),and the normonatremia group(n=54).RESULTS In the present study,there was a significant association between the high serum sodium concentrations,excessive persistent inflammation,immunosuppression and catabolism syndrome and chronic critical illness,while rapid recovery had an apparent association with normonatremia.Moreover,multivariable analyses revealed the following independent risk factors for IAH:Total urinary output over the preceding three days[odds ratio(OR)=1.09;95%CI:1.02–1.17;P=0.014],enteral nutrition(EN)sodium content of 500 mg(OR=2.93;95%CI:1.13–7.60;P=0.027),and EN sodium content of 670 mg(OR=6.19;95%CI:1.75–21.98;P=0.005)were positively correlated with the development of IAH.Notably,the area under the curve for total urinary output over the preceding three days was 0.800(95%CI:0.678–0.922,P=0.001).Furthermore,maximum serum sodium levels,the duration of hypernatremia,and varying sodium correction rates were significantly associated with 28-day in-hospital mortality in septic shock patients(P<0.05).CONCLUSION The present findings illustrate that elevated serum sodium level was significantly associated with a poor prognosis in septic shock patients in the ICU.It is highly recommended that hypernatremia be considered a potentially important prognostic indicator for the outcome of septic shock.

Success of intravenous immunoglobulin and steroids in managing severe COVID-19 following lung transplantation:A case report

BACKGROUND Coronavirus disease 2019(COVID-19)pneumonia with severe septic shock and acute respiratory distress syndrome(ARDS)are critical illnesses for patients following transplant.Intravenous immunoglobulin(IVIG)plays a role in both immune support and inflammation control,especially in immunocompromised patients.This case report describes the first successful experience using IVIG and pulse steroids to manage this critical condition following lung transplantation.CASE SUMMARY A 65-year-old male patient reported a history of chronic obstructive pulmonary disease and poor lung function and received bilateral sequential lung transplantations.Postoperatively,he developed COVID-19 pneumonia,severe septic shock,and ARDS.He recovered from this critical condition after empirical antibiotics administration and veno-venous extracorporeal membrane oxygenation,in addition to IVIG and pulse steroids.CONCLUSION IVIG is a valuable adjunct in managing severe sepsis in lung transplant recipients after COVID-19 infection.We aim,for the first time,to report the success of such a management approach for COVID-19 ARDS and sepsis in the post-lung transplant setting.With further investigations,this is a starting point for wider analysis of such an approach in this setting and consequently helps guide clinical practice for such a challenging patient population moving forward.

Current role of extracorporeal membrane oxygenation for the management of trauma patients:Indications and results

Extracorporeal membrane oxygenation(ECMO)has emerged as a vital circulatory life support measure for patients with critical cardiac or pulmonary conditions unresponsive to conventional therapies.ECMO allows blood to be extracted from a patient and introduced to a machine that oxygenates blood and removes carbon dioxide.This blood is then reintroduced into the patient’s circulatory system.This process makes ECMO essential for treating various medical conditions,both as a standalone therapy and as adjuvant therapy.Veno-venous(VV)ECMO primarily supports respiratory function and indicates respiratory distress.Simultaneously,veno-arterial(VA)ECMO provides hemodynamic and respiratory support and is suitable for cardiac-related complications.This study reviews recent literature to elucidate the evolving role of ECMO in trauma care,considering its procedural intricacies,indications,contraindications,and associated complications.Notably,the use of ECMO in trauma patients,particularly for acute respiratory distress syndrome and cardiogenic shock,has demonstrated promising outcomes despite challenges such as anticoagulation management and complications such as acute kidney injury,bleeding,thrombosis,and hemolysis.Some studies have shown that VV ECMO was associated with significantly higher survival rates than conventional mechanical ventilation,whereas other studies have reported that VA ECMO was associated with lower survival rates than VV ECMO.ECMO plays a critical role in managing trauma patients,particularly those with acute respiratory failure.Further research is necessary to explore the full potential of ECMO in trauma care.Clinicians should have a clear understanding of the indications and contraindications for the use of ECMO to maximize its benefits in treating trauma patients.

Patients admitted in the intensive care unit after solid organ or bone marrow transplantation:Retrospective cohort study

BACKGROUND Solid organ transplantation(SOT)and hematopoietic stem cell transplantation(HSCT)revolutionized the survival and quality of life of patients with malignant diseases,various immunologic,and metabolic disorders or those associated with a significant impairment in a patient's quality of life.AIM To investigate admission causes and treatment outcomes of patients after SOT or HSCT treated in a medical intensive care unit(ICU).METHODS We conducted a single-center,retrospective epidemiological study in the medical ICU at the University Hospital Centre Zagreb,Croatia covering the period from January 1,2018 to December 31,2023.RESULTS The study included 91 patients with either SOT[28 patients(30.8%)]or HSCT[63 patients(69.2%)].The median age was 56(43.2-64.7)years,and 60.4%of the patients were male.Patients with SOT had more comorbidities than patients after HSCT[χ^(2)(5,n=141)=18.513,P<0.001].Sepsis and septic shock were the most frequent reasons for admission,followed by acute respiratory insufficiency in patients following HSCT.Survival rate significantly differed between SOT and HSCT[χ^(2)(1,n=91)=21.767,P<0.001].ICU survival was 57%in the SOT and 12.7%in the HSCT group.The need for mechanical ventilation[χ^(2)(1,n=91)=17.081,P<0.001]and vasopressor therapy[χ^(2)(1,n=91)=36.803,P<0.001]was associated with survival.The necessity for acute renal replacement therapy did not influence patients'survival[χ^(2)(1,n=91)=0.376,P=0.54].In the subgroup of patients with infection,90%had septic shock,and the majority had positive microbiological samples,mostly Gram-negative bacteria.The ICU survival of patients with sepsis/septic shock cumulatively was 15%.The survival of SOT patients with sepsis/shock was 45%.CONCLUSION Patients with SOT or HSCT are frequently admitted to the ICU due to sepsis and septic shock.Despite advancements in critical care,the mortality rate of patients with refractory septic shock and multiorgan failure in this patient population is extremely high.Early recognition and timely ICU admittance might improve the outcome of patients,especially after HSCT.

冲击点火反应过程中RDX基PBX炸药的热辐射特性

研究冲击波流场中聚合物黏结炸药的热辐射特性可能是获取相关物质组分温度数据的重要途径。利用二级轻气炮加载技术、瞬态辐射测温方法及粒子速度剖面测量技术,探讨了聚合物黏结炸药/氟化锂窗口界面的热辐射特性及其与界面压力之间的相关性;同时,还优化了聚合物黏结炸药样品制备方法,显著抑制了包裹气体和界面间隙发光背景,给出了界面辐亮度数据及界面温度数据。结果表明,在连续2次冲击加载过程中,界面温度随时间衰减特征与反应产物的等熵膨胀行为密切相关,界面温度反映了界面处产物温度的演化行为,为直接观测点火反应和起爆释能期间非均质复合炸药的反应产物温度数据提供了一种可行的技术途径。

Cardiovascular involvement in multisystem inflammatory syndrome in children and midterm follow-up from a pediatric tertiary center in India

BACKGROUND In multisystem inflammatory syndrome in children(MIS-C)with coronavirus disease 2019,there was paucity of data from low-income and middle-income countries on cardiovascular involvement and its longitudinal outcomes.We planned to estimate the pattern of cardiovascular involvement among children with MIS-C and its mid-term outcomes.AIM To determine association between cardiovascular abnormalities and clinical and laboratory parameters.To study the time-line for resolution of various abnormalities.METHODS In this prospective study done in a tertiary care hospital,270 were recruited from June 2020 to January 2022.Baseline demographic data and clinical presentation were recorded.Laboratory parameters and echocardiography were done at admission.Follow-up was done at 2 weeks,3 months,6 months and 1 year after diagnosis.Descriptive statistics were used for parametric and non-parametric data.Risk factors were identified by multivariate regression analysis.RESULTS The 211(78.2%)had cardiac involvement and 102 needed intensive care unit(ICU)admission.Cardiovascular abnormalities observed were shock 123(45.6%),coronary dilatation 28(10.4%),coronary aneurysm 77(28.5%),left ventricular(LV)dysfunction 78(29.3%),mitral regurgitation(MR)77(28.5%)and pericardial effusion 98(36.3%).Coronary artery aneurysm/dilatation during follow-up at 2 weeks and 1 year were 25.7%and 0.9%respectively.Multivariate regression analysis revealed breathlessness[odds ratio(OR)=3.91,95%CI:1.25-12.21,P=0.019]and hi-flow nasal cannula(HFNC)support(OR=8.5,95%CI:1.06-68.38,P=0.044)as predictors of cardiovascular involvement.Higher mean age(OR=1.16,95%CI:1.02-1.32,P=0.026),breathlessness(OR=4.99,95%CI:2.05-12.20,P<0.001),gallop(OR=4.45,95%CI:0.41-2.52,P=0.016),MR(OR=3.61,95%CI:1.53-8.53,P=0.004)and invasive ventilation(OR=4.01,95%CI:1.28-12.58,P=0.017)were predictive of LV dysfunction.Altered sensorium(OR=4.96,95%CI:2.23-11.02,P<0.001),headache(OR=6.61,95%CI:1.46-29.92,P=0.014),HFNC(OR=7.03,95%CI:2.04-24.29,P=0.002),non-rebreathing mask usage(OR=21.13,95%CI:9.00-49.61,P<0.001)and invasive ventilation(OR=5.64,95%CI:1.42-22.45,P=0.014)were risk factors for shock.Anemia was a risk factor for coronary involvement(OR=3.09,95%CI:1.79-5.34,P<0.001).CONCLUSION Significant number of children with MIS-C had cardiovascular involvement contributing to higher ICU management.Although shock resolved quickly,resolution of ventricular function and coronary abnormalities were slower,and hence warrants a structured long-term follow-up protocol.

皮瓣缺血再灌注损伤的发病机制及治疗进展

背景:皮瓣移植技术是治疗严重组织缺损的常用外科手术方式,但术后因缺血再灌注损伤容易引发皮瓣坏死,因此提高移植皮瓣的存活率仍是目前重要的研究课题。目的:综述皮瓣缺血再灌注损伤的发病机制及最新治疗进展。方法:检索CNKI、万方和PubMed数据库中2014-2024年发表的相关文献,中文检索词为“皮瓣,缺血再灌注损伤,炎症反应,氧化应激反应,Ca^(2+)超载,细胞凋亡,间充质干细胞,富血小板血浆,信号通路,冲击波,预处理”,英文检索词为“flap,ischemia-reperfusion injury,inflammatory response,oxidative stress,Ca^(2+)overload,apoptosis,mesenchymal stem cells,platelet-rich plasma,signaling pathways,Shock wave,Pretreatment”。通过阅读文章剔除研究内容与文章主题关系不大、质量较差及内容陈旧文献,最终纳入77篇文献进行归纳总结。结果与结论:皮瓣缺血再灌注损伤损伤可能与炎症反应、氧化应激反应、Ca^(2+)超载、细胞凋亡等病理因素有关,引起皮瓣血管内皮细胞凋亡、血管损伤和微循环障碍,最终导致皮瓣坏死。研究发现,间充质干细胞移植、富血小板血浆、信号通路调节剂、冲击波及预处理等治疗方法均可以从不同方向在不同程度上缓解皮瓣缺血再灌注损伤,降低移植皮瓣的坏死率和坏死面积。关于皮瓣缺血再灌注损伤的治疗方法虽然很多,然而临床还未形成统一有效的治疗方法,各种治疗方法的优缺点也未进行对比研究,并且大部分研究都停留在动物实验阶段,临床观察研究甚少,因此未来还需要进行大量研究,逐步由动物实验向临床迈进,以便更好地为临床服务。