本文選題：缺血再灌注損傷 + 大鼠大腦中動(dòng)脈閉塞模型�。� 參考：《復(fù)旦大學(xué)》2014年博士論文

【摘要】：第一部分大鼠急性缺血性腦卒中BBB通透性動(dòng)態(tài)變化研究目的：本實(shí)驗(yàn)采用大鼠大腦中動(dòng)脈閉塞(Middle cerebral artery occlusion, MCAO)模型,運(yùn)用動(dòng)態(tài)對(duì)比增強(qiáng)(Dynamic contrast enhanced, DCE)磁共振成像(Magnetic resonance imaging, MRI)技術(shù),研究急性缺血性腦卒中血腦屏障(Blood brain barrier, BBB)通透性動(dòng)態(tài)變化規(guī)律。材料與方法：采用線栓栓塞法制備SD大鼠MCAO模型60只,根據(jù)缺血時(shí)間(3 h、6 h、永久栓塞)及再通時(shí)間(2 h、6 h、12 h、24 h),隨機(jī)分為12組,每組5只。各組相應(yīng)時(shí)間點(diǎn)行MRI檢查,所得圖像經(jīng)西門子工作站處理后測(cè)量BBB通透性參數(shù)：Ktrans?Ve、Kep及rKtrans、rVe、 rKep,觀察各組BBB通透性變化,并與病理學(xué)“金標(biāo)準(zhǔn)”伊文思藍(lán)(Evans blue, EB)染色漏出量相對(duì)比。結(jié)果：缺血3小時(shí)、6小時(shí)組再灌注后BBB通透性均呈現(xiàn)雙相性改變,即再通后2小時(shí)及6小時(shí)rKtrans值與rVe值升高,rKep值降低,BBB通透性增高,再通12小時(shí)BBB通透性降低,再通24小時(shí)通透性再次升高,均以再通6小時(shí)BBB通透性最大,缺血6小時(shí)組各再通時(shí)間點(diǎn)均較缺血3小時(shí)組BBB通透性大。永久栓塞組BBB通透性呈現(xiàn)單相性改變,即隨著缺血時(shí)間延長(zhǎng)BBB通透性持續(xù)輕度增高。MRI觀察結(jié)果與EB染色漏出量相一致。各組組內(nèi)及組間比較rKtrans值、rVe值與rKep值均具統(tǒng)計(jì)學(xué)差異(P0.05),且Ktrans值與Ve值呈正相關(guān)(相關(guān)系數(shù)為0.93,P0.01)；Ktrans值與Kep值呈負(fù)相關(guān)(相關(guān)系數(shù)為-0.84,P0.01)；Ve值與Kep值呈負(fù)相關(guān)(相關(guān)系數(shù)為-0.8,P0.01)。結(jié)論：缺血再灌注組BBB通透性呈雙相性變化,永久栓塞組BBB通透性呈單相性變化。DCE-MRI技術(shù)可準(zhǔn)確反映腦缺血后BBB通透性改變,BBB通透性受缺血時(shí)間及再通時(shí)間兩個(gè)因素影響,隨著缺血時(shí)間的延長(zhǎng),BBB通透性增加所需的時(shí)間就越短,BBB破壞的時(shí)間較早,且破壞程度明顯增加。第二部分DCE-MRI技術(shù)預(yù)測(cè)急性缺血性腦卒中HT的實(shí)驗(yàn)研究目的：本實(shí)驗(yàn)通過觀察缺血再灌注損傷引起的出血性轉(zhuǎn)換(Hemorrhagic transformation, HT)發(fā)生率,從而進(jìn)一步探討DCE-MRI技術(shù)早期預(yù)測(cè)HT可行性。材料與方法：健康雄性SD大鼠50只,隨機(jī)分為5組,每組10只,分別為3 h、4.5 h、6h、7.5h、9h缺血再灌注組。所有實(shí)驗(yàn)動(dòng)物均建立MCAO缺血再灌注模型,并于再灌注前即刻及灌注后6小時(shí)分別行MRI檢查,掃描序列包括：DWI(Diffusion weighted imaging, DWI)、DCE-MRI及磁敏感加權(quán)成像(Susceptibility weighted imaging, SWI)。根據(jù)SWI圖像及最終病理結(jié)果,比較性分析再灌注前HT組及無HT組組間rKtrans、rVe及rKep值差異性,并行二分類Logistic回歸及ROC曲線分析,判斷再灌注前預(yù)測(cè)HT發(fā)生的危險(xiǎn)因素及其敏感性、特異性。結(jié)果：3 h、4.5h缺血再灌注組均未見HT發(fā)生,6h、7.5h、9h缺血再灌注組中HT發(fā)生分別為1只、3只及4只,缺血6h后HT發(fā)生率為26.7%�；仡櫺苑治鯤T組及無HT組再灌注前rKtrans、rKep、rVe值,再灌注前紋狀體區(qū)及皮層區(qū)rKtrans及rVe值HT組均高于無HT組(P0.05),而再灌注前紋狀體區(qū)及皮層區(qū)rKep值兩組間無統(tǒng)計(jì)學(xué)差異(P0.05)。二分類Logistic回歸分析顯示：僅紋狀體區(qū)rKtrans值是預(yù)測(cè)HT的危險(xiǎn)因素,其OR值為263.614,結(jié)合ROC曲線,取Youden指數(shù)最大值為預(yù)測(cè)出血的最佳臨界點(diǎn),紋狀體rKtrans值為1.565時(shí),預(yù)測(cè)HT的敏感性91.4%,特異性為73.9%。結(jié)論：紋狀體區(qū)rKtrans值可成為預(yù)測(cè)急性缺血性腦卒中繼發(fā)HT的影像學(xué)指標(biāo)。除了時(shí)間點(diǎn)外(大于6小時(shí)),結(jié)合紋狀體區(qū)rKtrans值,將有助于早期預(yù)測(cè)HT。第三部分DCE-MRI技術(shù)預(yù)測(cè)缺血再灌注損傷的實(shí)驗(yàn)研究目的：本實(shí)驗(yàn)觀察不同缺血時(shí)間點(diǎn)大鼠MCAO模型缺血再灌注前、后影像學(xué)及行為學(xué)動(dòng)態(tài)變化,分析DCE.MRI參數(shù)與急性缺血性腦卒中預(yù)后的關(guān)系,探討有效預(yù)測(cè)及監(jiān)測(cè)缺血再灌注損傷的影像學(xué)指標(biāo)。材料與方法：健康雄性SD大鼠50只,隨機(jī)分為5組,每組10只,分別為3h、4.5h、6h、7.5h、9h缺血再灌注組。所有實(shí)驗(yàn)動(dòng)物均建立MCAO缺血再灌注模型,每組動(dòng)物于再灌注前即刻及再灌注后6小時(shí)分別行MRI檢查,根據(jù)SWI圖像及病理學(xué)結(jié)果將發(fā)生HT的實(shí)驗(yàn)動(dòng)物剔除,其余實(shí)驗(yàn)動(dòng)物為入組實(shí)驗(yàn)動(dòng)物,入組實(shí)驗(yàn)動(dòng)物的DCE原始數(shù)據(jù)經(jīng)工作站后處理,測(cè)量得到缺血腦組織皮層區(qū)及紋狀體區(qū)rKtrans、rVe及rKep值,并進(jìn)一步求得灌注前、后的各參數(shù)差值(△rKtrans、△rVe及△rKep)；入組實(shí)驗(yàn)動(dòng)物于再灌注前即刻及再灌注后24小時(shí)行神經(jīng)功能行為學(xué)評(píng)分,求得再灌注前、后神經(jīng)功能行為學(xué)評(píng)分差值,神經(jīng)功能行為學(xué)評(píng)分差值為正值認(rèn)為預(yù)后良好,神經(jīng)功能行為學(xué)評(píng)分差值為負(fù)值或0認(rèn)為預(yù)后不良；將代表BBB通透性的各參數(shù)差值與代表最終預(yù)后的神經(jīng)功能行為學(xué)評(píng)分差值進(jìn)行統(tǒng)計(jì)分析,尋找可以預(yù)測(cè)腦卒中缺血再灌注損傷的DCE指標(biāo),確定最佳預(yù)測(cè)指標(biāo)及其最佳臨界點(diǎn)、敏感性及特異性。結(jié)果：不同缺血時(shí)間點(diǎn)治療前后紋狀體區(qū)rKtrans值有顯著差異(F=64.94,P=0.000),多重比較,組間ArKtrans值差異均有統(tǒng)計(jì)學(xué)意義,ArKtrans值隨缺血時(shí)間延長(zhǎng)逐漸增高。不同缺血時(shí)間點(diǎn)治療前后皮層區(qū)rKtrans值有顯著差異(F=6.973,P=0.000),多重比較,缺血113h、4.5h及6h組間ArKtrans值差異無統(tǒng)計(jì)學(xué)意義(P0.05),但均高于缺血7.5h及9h組的ArKtrans(P0.05),缺血7.5h與9h組間ArKtrans值差異無統(tǒng)計(jì)學(xué)意義(P0.05)。不同缺血時(shí)間點(diǎn)治療后紋狀體區(qū)rVe間有顯著差異(F=67.935,P=0.000),多重比較,缺血4.5 h及6h組間△rVe值差異無統(tǒng)計(jì)學(xué)意義(P0.05),余組間ArVe值比較差異均有統(tǒng)計(jì)學(xué)意義(P0.05)。不同缺血時(shí)間點(diǎn)治療后皮層區(qū)rVe值間有顯著差異(F=70.352,P=0.000),多重比較,缺血4.5 h及6 h間ArVe值差異無統(tǒng)計(jì)學(xué)意義(P0.05),余組間ArVe值比較差異均有統(tǒng)計(jì)學(xué)意義(P0.05)。不同缺血時(shí)間點(diǎn)治療后紋狀體區(qū)rKep值間有顯著差異(F=46.808,P=0.000),多重比較,缺血3 h及4.5 h間ΔrKep值差異無統(tǒng)計(jì)學(xué)意義(P0.05),余組間ΔrKep值比較差異均有統(tǒng)計(jì)學(xué)意義(P0.05)。不同缺血時(shí)間點(diǎn)治療后皮層區(qū)rKep值間有顯著差異(F=143.317,P=0.000),多重比較,缺血3h及4.5h間ArKep值差異無統(tǒng)計(jì)學(xué)意義(P0.05),余組間ArKep值比較差異均有統(tǒng)計(jì)學(xué)意義(P0.05)。將指標(biāo)進(jìn)行二分類Logistic回歸分析顯示：紋狀體區(qū)ArKtrans值,皮層區(qū)△rVe值是預(yù)后不良的危險(xiǎn)因素,其OR值分別為35.42及19.13,進(jìn)一步結(jié)合ROC曲線,取Youden指數(shù)最大值,為判斷預(yù)后的最佳臨界點(diǎn),紋狀體ArKtrans值為1.020時(shí),診斷敏感性93.3%,特異性為88.9%；皮層區(qū)△rVe為1.036,診斷敏感性86.7%,特異性為88.9%。結(jié)論：結(jié)合治療前后紋狀體區(qū)ArKtrans值及皮層區(qū)△rVe值,將有助于早期判斷再灌注損傷,合理安排進(jìn)一步干預(yù)治療。
[Abstract]:The first part of the study on the dynamic changes of BBB permeability in rats with acute ischemic stroke. The experiment was conducted by using the Middle cerebral artery occlusion (MCAO) model in rats and the dynamic contrast enhancement (Dynamic contrast enhanced, DCE) magnetic resonance imaging (Magnetic resonance) technique to study the acute ischemia. The dynamic changes in the permeability of Blood brain barrier (BBB). Materials and methods: 60 MCAO models of SD rats were prepared by thread embolism method. According to the ischemia time (3 h, 6 h, permanent embolism) and the time of re passage (2 h, 6 h, 12 h, 24 h), 12 groups, 5 in each group. After treatment by SIEMENS workstation, BBB permeability parameters were measured: Ktrans? Ve, Kep and rKtrans, rVe, rKep, observe the changes of BBB permeability, and compare with the pathological "gold standard" Evans blue (Evans blue, EB) stain. Results: 3 hours of ischemia, 6 hours after reperfusion, BBB permeability is biphasic change, that is, after repass The value of rKtrans and rVe increased at 2 hours and 6 hours, the rKep value decreased, the permeability of BBB increased, the BBB permeability was reduced for 12 hours, and the 24 hour permeability increased again. All the 6 hour BBB permeability was the largest. The time points of the 6 hour ischemia group were all more BBB permeability than the 3 hour ischemia group. The BBB permeability in the permanent embolism group showed single-phase permeability. The change, that is, with the prolonged BBB permeability prolonged slightly increased with the duration of ischemia, the results of.MRI observation were consistent with the amount of EB dyed leaking. In each group and between groups, the rKtrans value, rVe value and rKep value were statistically different (P0.05), and Ktrans value was positively correlated with the Ve value (the correlation coefficient was 0.93, P0.01); Ktrans values were negatively correlated with Kep values (correlation coefficient). -0.84, P0.01); Ve value is negatively correlated with Kep value (correlation coefficient is -0.8, P0.01). Conclusion: BBB permeability in ischemia reperfusion group is dual phase change, BBB permeability in permanent embolism group is single-phase change of.DCE-MRI technique can accurately reflect the change of BBB permeability after cerebral ischemia, BBB permeability is affected by two factors of ischemia time and repassage time. With the prolongation of ischemic time, the shorter the time required for the increase of BBB permeability, the earlier time of BBB destruction and a significant increase in damage. The objective of the experimental study on the prediction of acute ischemic stroke HT by the second part of DCE-MRI technique: this experiment was conducted by observing the hemorrhagic transformation (Hemorrhagic transformation, HT) induced by ischemia-reperfusion injury. To further explore the occurrence rate, and further explore the feasibility of early prediction of HT by DCE-MRI technology. Materials and methods: 50 healthy male SD rats were randomly divided into 5 groups, 10 rats in each group, 3 h, 4.5 h, 6h, 7.5h, and 9h ischemia-reperfusion group. All experimental animals were established the MCAO ischemia reperfusion model, and were performed MRI before reperfusion immediately and 6 hours after perfusion, respectively. The scanning sequence includes: DWI (Diffusion weighted imaging, DWI), DCE-MRI and magnetic sensitive weighted imaging (Susceptibility weighted imaging, SWI). According to SWI images and final pathological results, the difference between HT group and no group before reperfusion is comparatively analyzed, and the parallel two classification regression and curve analysis are carried out. To determine the risk factors and sensitivity of HT before reperfusion, and the sensitivity and specificity. Results: 3 h, 4.5H ischemia reperfusion group did not have HT, 6h, 7.5h, 9h ischemia reperfusion group were 1, 3 and 4 respectively, and the incidence of HT was 26.7%. retrospective analysis of HT group and no group before reperfusion, before reperfusion, before reperfusion, before reperfusion, before reperfusion, reperfusion before reperfusion, before reperfusion, before reperfusion before reperfusion The rKtrans and rVe value HT groups in the striatum and cortical areas were higher than those in the non HT group (P0.05), but there was no statistical difference between the two groups in the striatum and the cortical areas before reperfusion (P0.05). The two classification Logistic regression analysis showed that the rKtrans value of the striatum was the risk factor for predicting HT, and the OR value was 263.614. The value is the best critical point for predicting bleeding. When the rKtrans value of the striatum is 1.565, the sensitivity of HT is predicted and the specificity is 73.9%. conclusion: the rKtrans value in the striatum can be used to predict the secondary HT in the acute ischemic stroke. Besides the time point (greater than 6 hours) and the rKtrans value of the striatum, it will be helpful to predict HT. early. The third part of the experimental study on the prediction of ischemia-reperfusion injury by DCE-MRI technique. The experiment observed the dynamic changes of posterior image and behavior before ischemia reperfusion in MCAO model of rats with different ischemic time points, and analyzed the relationship between the DCE.MRI parameters and the prognosis of acute ischemic stroke, and explored the effective prediction and monitoring of ischemia reperfusion injury. Materials and methods: 50 healthy male SD rats were randomly divided into 5 groups, 10 rats in each group, which were 3h, 4.5H, 6h, 7.5h, and 9h ischemia reperfusion group. All the experimental animals established the MCAO ischemia-reperfusion model. Each group was examined immediately before reperfusion and 6 hours after reperfusion, respectively, according to the SWI image and pathological results. The experimental animals were eliminated with HT, and the rest of the experimental animals were included in the experimental animals. The DCE original data of the experimental animals were treated by the workstation, and the rKtrans, rVe and rKep values of the cortex and striatum of the ischemic brain tissue were measured, and the difference values of the parameters (delta rKtrans, Delta rVe and delta rKep) before the perfusion were further obtained. Nerve functional behavioral score was scored before reperfusion immediately before reperfusion and 24 hours after reperfusion. The difference between the neurological functional behavior score and the neurological functional behavior score was positive, the difference between the neurological functional behavior score was negative or 0 thought the prognosis was bad, and the difference of the parameters representing the BBB permeability was poor. The value and the difference between the neurobehavioral behavioral score and the final prognosis were statistically analyzed to find the DCE index that could predict the ischemic reperfusion injury of cerebral apoplexy, and determine the best predictor and its best critical point, sensitivity and specificity. Results: there were significant differences in the rKtrans value of the striatum in different ischemic time points (F=64.94, P=0 .000), with multiple comparison, the difference of ArKtrans values between groups had statistical significance, and the ArKtrans value increased gradually with the prolongation of ischemic time. There was a significant difference in the rKtrans value of the cortical region before and after the treatment of different ischemic points (F=6.973, P=0.000), multiple comparison, and there was no statistically significant difference in ArKtrans values between the ischemic 113h, 4.5H and 6h groups (P0.05), but all higher than those of the ischemic 7.5h. And ArKtrans (P0.05) of group 9h, there was no significant difference in ArKtrans between ischemic 7.5h and 9h group (P0.05). There was significant difference between rVe (F=67.935, P=0.000) in the striatum after different ischemic time points (F=67.935, P=0.000), and there was no significant difference between 4.5 h and 6h groups. P0.05). There were significant differences (F=70.352, P=0.000) between different ischemic time points (F=70.352, P=0.000). There was no statistically significant difference in ArVe values between 4.5 h and 6 h in ischemia (P0.05), and there were significant differences in ArVe values between the remaining groups (P0.05). There was significant difference between the rKep values of the striatum after the treatment of different ischemic points (F=46.808, 000), multiple comparison, there was no significant difference in the value of delta rKep between 3 h and 4.5 h of ischemia (P0.05), and there was significant difference in the value of delta rKep between the remaining groups (P0.05). There was significant difference between the rKep values of the cortical region after the different ischemic time points (F=143.317, P=0.000), the multiplicity ratio, the ArKep value difference between the 3H and 4.5H ischemia, the remaining group The difference of ArKep value was statistically significant (P0.05). The two classification Logistic regression analysis showed that the ArKtrans value of the striatum, the rVe value of the cortical region was the risk factor of poor prognosis, the OR value was 35.42 and 19.13 respectively, and the maximum value of the Youden index was further combined with the ROC curve, which was the best critical point to judge the prognosis. When the body ArKtrans value is 1.020, the diagnostic sensitivity is 93.3%, the specificity is 88.9%, the cortical area Delta rVe is 1.036, the diagnostic sensitivity is 86.7%, the specificity is 88.9%. conclusion: the ArKtrans value of the striatum and the delta rVe value of the cortex area before and after the treatment will be helpful to the early judgment of reperfusion injury and the rational arrangement of the intervention treatment.
【學(xué)位授予單位】：復(fù)旦大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2014
【分類號(hào)】：R445.2;R743.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 全冠民;袁濤;魏志剛;劉懷軍;尚華;高國(guó)棟;雷建明;李彩英;耿左軍;;超高場(chǎng)MR擴(kuò)散系數(shù)值對(duì)兔急性腦梗死后出血的預(yù)測(cè)價(jià)值[J];中國(guó)臨床醫(yī)學(xué)影像雜志;2009年04期

，

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