兔急性肺损伤后肺内VEGF时序性表达的研究

目的观察大潮气量机械通气致兔急性肺损伤(acutelung injury,ALI)后,肺组织中血管内皮生长因子(VEGF)的动态变化,探讨其在损伤时间推断中应用的价值。方法57只雄性新西兰大白兔随机分为正常组(3只)、对照组(27只)和实验组(27只)。机械通气(V_T 60mL/kg)致AL后于0,1,3,6,12,18,24,36,48h各处死动物3只。取肺组织,测量右上肺组织湿干重比(W/D),肺组织进行HE及免疫组织化学染色并进行图像定量分析,观察VEGF变化规律。结果正常组VEGF有低水平表达;大潮气量机械通气1min后至肺损伤后12h,实验组VEGF表达水平与正常组无明显差异(P>0.05);12～48h随损伤时间的延长VEGF表达水平持续上升,48h仍处于较高水平,其间各时间点VEGF表达水平与正常组比较均有显著性差异(P<0.05)。结论大潮气量机械通气致兔ALI 2d内,VEGF在肺组织炎症发生、发展和愈合修复过程中存在时间相关性,对法医病理推断呼吸机所致的ALI时间具有参考价值。     

体外培养大鼠大脑皮质星形胶质细胞损伤后TGF-β1表达研究

目的观察体外培养星形胶质细胞损伤后TGF-β1的表达变化,进一步了解脑损伤修复的分子机制。方法取出生后24h内SD大鼠大脑皮质进行星形胶质细胞体外分离培养和纯化。随机分为对照组和机械性划痕损伤后30min、1h、3h、6h、12h、24h、3d、7d组,应用ABC法检测不同时间段TGF-β1表达的差异。结果体外培养星形胶质细胞的纯度达95%以上。对照组TGF-β1未见明显表达,TGF-β1在损伤后6h表达开始增加,3d时达高峰,7d时表达明显减少。伤后6h、12h、24h、3d、7d与对照组比较,其差异均有显著性(P0.01)。结论机械性划痕损伤后TGF-β1表达与在体动物实验模型一样具有时序性变化规律,可望成为脑损伤时间的推断依据之一。     

人体皮肤切创纤维连接蛋白EDA、EDB的表达与损伤时间关系的研究

目的研究纤维连接蛋白(fibronectin,FN)可变剪接片段EDA、EDB在人体皮肤切创的表达情况,并摸索EDA、EDBmRNA在离体皮肤上最长检出时限,以期为早期损伤时间的推断提供实用的参考指标。方法采用DIG标记的反意RNA探针,原位杂交检测人体皮肤在损伤早期(从30min开始)FNEDA、EDBmRNA表达的变化。结果正常人体皮肤无EDA、EDBmRNA表达;在损伤早期(≤3h)FNEDA、EDB的表达随时间的延长而呈现一种不断上升的趋势;EDA、EDBmRNA主要出现在表皮基底层细胞;EDA、EDBmRNA在标本离体后4h就不能检测到。结论FNEDA、EDB可作为早期损伤时间推断的较理想的参考指标,但原位杂交的检测方法不适用于实际应用。     

人皮肤组织刺、切创后IL-8表达的免疫组织化学研究

为探讨人皮肤刺、切创后白细胞介素 8(interleukin 8,IL 8)在推断皮肤损伤时间中的应用价值 ,本研究应用免疫组化技术对 5 2例不同损伤时间人体皮肤刺、切创组织中IL 8的表达进行了研究。伤后 4h的损伤皮肤组织中可见部分的多核粒细胞表达IL 8。伤后 12～ 2 4h ,大部分浸润的多核粒细胞及部分单核细胞为IL 8阳性。随伤后时间延长 ,IL 8阳性细胞以单核及成纤维细胞为主。伤后 4～ 6h的皮肤中 ,IL 8阳性细胞比率较低 ,为 16 0±10 1%。伤后 1～ 4d达高峰 ,为 5 9 6± 8 7%。其后逐渐减少。本研究结果表明 ,IL 8的表达可用于皮肤刺、切创后损伤时间的推断。     

兔皮肤钝器伤IL-1β、COX-2和MCP-1 mRNA表达与法医学应用

目的应用荧光定量PCR技术检测兔皮肤钝器伤后IL-1β、COX-2和MCP-1mRNA的时序性表达规律,分析其与损伤时间的关系。方法分别在兔耳皮肤钝器伤后<0.5h,0.5h,1h,2h,3h,4h,5h,6h,8h,12h,24h,1d,3d,7d和死后10min,0.5h,1h取材,一步法提取组织总RNA,逆转录合成cDNA第一条链,荧光定量PCR检测IL-1β、COX-2和MCP-1mRNA逆转录合成第一条cDNA链的拷贝数,作统计学分析。结果IL-1βmRNA在钝器伤后<0.5h表达显著增强(P<0.001),0.5h达到峰值,至第2d降至基本水平;COX-2mRNA于创伤后0.5h表达显著增强(P<0.05)并持续强表达至24h开始下降,第2d降至正常;MCP-1 mRNA在钝器伤后于1h表达显著增强(P<0.05),于3h出现表达峰,至第3d降至正常;3个指标在死后各时间组与正常对照无明显表达差异。结论检测皮肤IL-1β、COX-2和MCP-1mRNA可对早期损伤时间的推断提供帮助,并且这三个指标都可以鉴别生前伤和死后伤。     

切创后细胞自噬及炎症因子的表达与损伤时间的关系

目的观察小鼠皮肤切创后不同时间细胞自噬与炎症细胞因子的变化,同时探讨这些变化与损伤时间之间的关系。方法采用RT-PCR及West-blot方法检测小鼠皮肤切创组织在不同时间Beclin-1、LC-3、IL-1α、IL-1β、MCP-1的基因表达及蛋白表达。结果皮肤切创后早期IL-1α、IL-1β基因的表达及蛋白表达水平有所升高,12小时达到最高值,而后呈下降的趋势;MCP-1的表达在损伤后6h开始升高,48h达到最高值,72h有所下降,而Beclin-1、LC3基因及蛋白表达在组织损伤后6h开始升高,24h到达到最高值而后下降。结论小鼠皮肤组织切创后细胞自噬的启动及自噬的最高值明显晚于炎性细胞因子的启动及炎症因子表达的最高值,实验发现当细胞自噬水平达到最高时,炎症因子的水平则开始表现为下降的趋势。这可能是随着切创组织中炎症因子释放的增多激活了细胞的自噬,而当自噬水平达到一定的程度又抑制过度的炎症反应。自噬与炎症因子的表达随着小鼠皮肤创面损伤后不同时间呈现出一定的变化规律,这为组织损伤后损伤的时间推断提供一定的参考。     

病毒性心肌炎急性期心肌胶原增生与TGF－β1的表达

目的:研究病毒性心肌炎急性期组织修复性病理改变,探索轻度病毒性心肌炎的法医病理学诊断方法.方法:以适量CoxsackieB3病毒感染Balb/c小鼠造成小鼠轻度病毒性心肌炎.利用苦味酸-酸性品红染色法观察病鼠心肌组织胶原纤维的增生情况,并对病鼠及9例人心肌炎心肌进行TGF-β1的LSAB免疫组化研究.结果:病鼠心肌组织内胶原纤维呈不同程度增生;心肌炎鼠及人心肌炎心肌组织可见大量TGF-β1表达;TGF-β1的表达与胶原纤维的增生呈正相关.结论:病毒性心肌炎急性期即存在组织修复性病理改变,TGF-β1的阳性表达是反映心肌炎症性损伤修复的灵敏指标.     

RT-PCR检测不同时间大鼠皮肤切创TGF-β_1mRNA表达

目的 探讨TGF-β_1mRNA在不同时间的表达变化及其与伤后经过时间的关系。方法 应用逆转录-聚合酶链反应(RT-PCR)分别对大鼠生前0.5h、1h、3h、6h、12h、48h、72h、96h、168h和死后0.5h、1h、3h的皮肤切创组织中的TGF-β_1mRNA表达变化进行检测,采用ID软件对凝胶扫描的数据进行密度分析。结果 TGF-β_1mRNA在生前皮肤切创后0.5h上升,3h开始急剧升高,48h含量达到峰值;死后皮肤切创未见TGF-β_1mRNA的表达。结论 大鼠皮肤切创TGF-β_1mRNA的表达具有时间相关性,RT-PCR是检测细胞因子在基因水平表达的灵敏方法。     

小鼠皮肤创伤愈合过程中IL-10在不同表达部位的组化定量研究

目的探讨小鼠皮肤创伤愈合过程中IL-10在不同表达部位的变化与损伤时间的关系。方法应用免疫组织化学技术和形态计量法,对小鼠不同时程皮肤切创组织中IL-10不同表达部位(表皮细胞及表皮下组织的浸润细胞)的变化进行研究。结果皮肤切创前后表皮层均有阳性表达,切创后1～3h表皮细胞阳性表达水平迅速升高,24h时降至较低水平,伤后48h表达水平再次升高,96h后逐渐回复到正常水平;表皮以下阳性部位主要是浸润的单核/巨噬细胞,损伤6h后阳性细胞在真皮、皮下组织及创口肉芽组织内逐渐增多,于伤后72h达最大值(51.41±3.12)%,96～168h阳性细胞数逐渐减少(29.38±2.64)%～(5.56±4.74)%。结论皮肤创伤修复过程中IL-10在不同表达部位的变化特点与皮肤损伤时间相关,检测其表达变化可望用于损伤时间推断。     

过度机械通气致肺损伤TNF-α、IL-1β及NF-κBp65的表达

目的探讨过度机械通气致肺损伤后,炎症因子TNF-α、IL-1β及NF-κBp65在肺组织中不同时间表达的变化规律。方法将51只雄性新西兰大白兔分为正常组、对照组、实验组。利用呼吸机建立过度机械通气致肺损伤模型。应用免疫印迹技术观察兔急性肺损伤后肺组织中TNF-α、IL-1β及NF-κBp65的表达,并用凝胶图像处理系统进行分析,所得数据经SPSS 10.0统计软件处理。结果正常组与各对照组之间比较,均无明显差异(P>0.05)。TNF-α在损伤后0h表达即增加,1h达高峰,以后逐渐下降,而在24h后又有反弹性增高;其中在0.5、24、48h组有差异性(P<0.05),1、3h组有显著差异性(P<0.01)。IL-1β在损伤后0.5h逐渐增加,3h达高峰,以后逐渐下降,其中在1、6、12、24h组有差异性(P<0.05),3h组有显著差异性(P<0.01)。NF-κBp65在损伤后0.5h逐渐增加,6h达高峰,以后逐渐下降,其中在1、12h组有差异性(P<0.05),3、6h组有显著性差异(P<0.01)。结论TNF-α、IL-1β及NF-κBp65在过度机械通气致VILI发病中有重要作用;TNF-α、IL-1β及NF-κBp65在损伤早期即表达,且在时间上有一定的变化规律,可为损伤时间的推断提供参考。     

在大鼠皮肤切创愈合过程中TGF-β_1基因及蛋白表达变化与损伤时间关系的实验研究

了解细胞因子在创伤及修复过程中的表达变化与损伤时间的关系。初步调查生前不同造创时间 ( 0 5h～16 8h)皮肤创缘组织在修复过程中TGF β1mRNA和蛋白质表达变化 ,并与死后伤 ( 0 5h～ 6h)上述变化进行比较。结果表明 ,在生前伤 ,TGF β1在上皮细胞的表达于损伤后 0 5h开始增强 ,以 2 4h～ 96h反应最强 ,除上皮细胞内表达外 ,还在肉芽组织的巨噬细胞和成纤维细胞表达。TGF β1的免疫印迹 (WesternBlot)分析表明 ,TGF β1蛋白表达的峰值在 16 8h ;TGF β1斑点杂交和原位杂交结果显示 ,mRNA的表达在伤后 3h开始 ,6h后明显 ,96h达峰值。死后损伤组在 0 5～ 3h内有免疫组化的弱～中度表达 ,但无mRNA的表达 ,3h后则均无任何表达。TGF β1在修复过程中的一些规律性变化及特点反映了与损伤时间的关系 ,可作为精确推断损伤时间的分子生物学标志。     

A preliminary study on the changes of expression of PDGF-beta,PDGFR-beta,TGF-beta 1, TGFR,bFGF and its relationship with the wound age in wound healing

OBJECTIVE: To explore the relationship between the expression change of cytokines and the wound age during the healing process of rats skin wound. METHODS: Immunohistochemical and image-analysis methods were performed on vital skin wounds(after incision 0.5-168 h am) and postmortem damage(after incision 0.5-6 h pm). RESULTS: The expression of the cytokines PDGF-beta, PDGFR-beta, TGF-beta 1, and bFGF in the epithelial cells was already enhanced since 0.5 h am after damage and their strongest expression reaction was seen at 24-96 h am. In addition, the expression of PDGF-beta, PDGFR-beta, TGF-beta 1 and bFGF was also found in the macrophages and the fibroblasts of the granulation tissue, and the expression changes in the postmortem damage group showed that the skin tissue within 0.5-3 h after incision showed immunohistochemical changes but weakly expression and 3 h thereafter no any change was found. CONCLUSION: The expression characteristics of the above mentioned cytokines in wound repair should be related to the wound age and it reminds therefore that they may be used as immunohistochemical criteria for accurate determining the wound age.     

Transforming growth factors (TGF-alpha and TGF-beta1) in the determination of vitality and wound age: immunohistochemical study on human skin wounds

In continuation of former investigations on proinflammatory cytokines, in the present study the relevance of the transforming growth factors TGF-alpha and TGF-beta1 was evaluated for the diagnosis of vitality and wound age. Paraffin sections from human skin wounds due to sharp force influence, which had been collected in operations and autopsies, were investigated using immunohistochemistry. The wound age varied from a few minutes to a maximum of 6 weeks with focus on the early post-traumatic interval up to 5h. Samples from uninjured skin were available as controls. TGF-alpha (n=74) was weakly expressed in normal skin and showed a marked increase in epidermal reactivity after a wound age of approximately 10 min. The maximum was between 30 and 60 min. TGF-beta1 (n=51) revealed constitutional expression only in connective tissue. An increase of immunohistochemical reaction was partially detected even in classical stab wounds (wound age of several minutes). The immunohistochemically detectable signal concerned--presumably due to an infiltration with TGF-beta-rich thrombocytes--large parts of the traumatized skin and also the epidermal layers (cellular and interstitial marking). TGF-beta1 peaked after a post-traumatic interval of 30-60 min. Both factors, especially TGF-beta1, remained detectable in elevated levels also in older wounds with an age of days to weeks (network in granulation tissue). TGF-alpha and TGF-beta1 can efficiently contribute to the estimation of vitality and wound age based on the evaluation of cytokine patterns. In particular, this applies to TGF-beta1 because of its easier evaluation and rapid up-regulation. Similar to other cytokines, the parallel investigation of control skin from the same individual must be recommended to eliminate variation in the basal expression.     

Time-dependent immunohistochemical detection of proinflammatory cytokines (IL-1beta,IL-6, TNF-alpha) in human skin wounds

The proinflammatory cytokines interleukin-1beta (IL-1beta), interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-alpha) hold important functions in the early and late courses of inflammation, trauma and wound healing. In the present study, human skin wounds due to sharp force (n = 105) were collected during surgery and autopsy. The wound age mainly varied from several minutes to 5 h, some specimens aged up to 6 weeks. Control specimens from uninjured skin were available in each case. After preparation of cryostat sections, immunohistochemistry was performed according to the APAAP technique, using monoclonal and polyclonal antibodies. The results were evaluated semiquantitatively. All markers were weakly expressed in normal human skin constitutively. However, the staining pattern changed significantly in vital wounds concerning epidermal layers, subepidermal cells, vessels and sweat glands. IL-1beta and IL-6 showed enhanced expression after 15 and 20 min at the earliest (increase of epidermal reactivity). After 30-60 and 60-90 min, respectively, marked expression was observed with these markers. Similar alterations were detectable with TNF-alpha after 15 and 60-90 min. The reactivity of all three markers persisted over several hours, then decreased to basal levels again and sometimes reappeared after days and in granulation tissue. Leukocytes reacting with IL-1beta and IL-6 appeared after approximately 2 h. CONCLUSION: proinflammatory cytokines can serve as a useful tool for the estimation of vitality and wound age, in particular in the early post-traumatic interval prior to leukocyte reaction. Autolysis did not play a role in the samples investigated (postmortem interval up to 8 days). Problems could sometimes rise from constitutive expression. Therefore, it is recommended to examine control samples from the same individual and to compare the reactivity with wound specimens.     

非同位素标记探针杂交分析白细胞端粒DNA长度

目的建立用非同位素标记探针杂交测定端粒DNA长度的方法,并探讨其法医学的应用价值。方法酚/氯仿抽提基因组DNA,限制性内切酶消化,0.8％琼脂糖凝胶电泳,Southern印迹,化学发光法检测端粒DNA谱带,与标准分子量DNA比较,积分光密度扫描计算端粒DNA平均长度。结果所测样本获得了较好的低背景杂交谱带,测得31~35岁端粒。DNA的平均长度为11.71kb,51~55岁平均为11.04 kb。结论用上述建立的方法初步显示年龄与端粒长度之间有一定的相关性,为法医学年龄的推断开辟了一个新的研究领域。     

大鼠皮肤切创愈合过程中ICAM-1及P选择素的表达

目的　探讨细胞间粘附分子 1(ICAM 1)及P选择素的表达变化与损伤时间的关系。方法　应用免疫组织化学技术 ,对实验大鼠不同损伤时间的生前伤 ( 5min～ 7d)及死后伤 ( 5～ 3 0min)皮肤组织中ICAM 1及P选择素的表达变化进行观察。结果　在生前损伤组中 ,ICAM 1最早在伤后 1h ,最迟至伤后 3d在表皮层中呈阳性表达 ;P选择素最早在伤后 10min ,最迟至伤后 5h即在血管内皮细胞中呈阳性表达。此外 ,ICAM 1还在炎症细胞及纤维母细胞中表达 ,且随损伤时间变化而呈规律性变化。在时间段分组 ,ICAM 1在第Ⅰ组 ( 5min～ 1h)中阳性细胞率极低( 0 41± 0 73 % ) ,第Ⅱ组 ( 3h～ 7h)及第Ⅲ组 ( 9h～ 12h)均呈显著性增高 ( 9 79± 3 74% ,2 3 3 3± 1 10 % ) ,至第Ⅳ组 ( 1d)达高峰 ( 3 0 5 8± 2 65 % ) ,其后逐渐减少。ICAM 1及P选择素在死后伤中均呈阴性表达。结论　ICAM 1及P选择素可作为法医学损伤时间判定的有效指标。     

Time-dependent immunohistochemical detection of proinflammatory cytokines (IL-1β, IL-6, TNF-α) in human skin wounds

The proinflammatory cytokines interleukin-1beta (IL-1β), interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α) hold important functions in the early and late courses of inflammation, trauma and wound healing. In the present study, human skin wounds due to sharp force (n=105) were collected during surgery and autopsy. The wound age mainly varied from several minutes to 5 h, some specimens aged up to 6 weeks. Control specimens from uninjured skin were available in each case. After preparation of cryostat sections, immunohistochemistry was performed according to the APAAP technique, using monoclonal and polyclonal antibodies. The results were evaluated semiquantitatively. All markers were weakly expressed in normal human skin constitutively. However, the staining pattern changed significantly in vital wounds concerning epidermal layers, subepidermal cells, vessels and sweat glands. IL-1β and IL-6 showed enhanced expression after 15 and 20 min at the earliest (increase of epidermal reactivity). After 30–60 and 60–90 min, respectively, marked expression was observed with these markers. Similar alterations were detectable with TNF-α after 15 and 60–90 min. The reactivity of all three markers persisted over several hours, then decreased to basal levels again and sometimes reappeared after days and in granulation tissue. Leukocytes reacting with IL-1β and IL-6 appeared after approximately 2 h. Conclusion: proinflammatory cytokines can serve as a useful tool for the estimation of vitality and wound age, in particular in the early post-traumatic interval prior to leukocyte reaction. Autolysis did not play a role in the samples investigated (postmortem interval up to 8 days). Problems could sometimes rise from constitutive expression. Therefore, it is recommended to examine control samples from the same individual and to compare the reactivity with wound specimens.     

Immunohistochemical study of basic fibroblast growth factor and vascular endothelial growth factor expression for age determination of cutaneous wounds

The authors investigated the expression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) during skin wound healing using immunohistochemical techniques. After a full-thickness incision was made on the dorsal skin, mice were killed 0.5, 1, 3, 8, 24, 72, 144, or 240 hours after incision, and the wound was excised. To evaluate the influences of postmortem degeneration, cutaneous wound excision was performed 1 to 5 days after the mice were killed. The excised wounds were stained by the conventional streptoavidin-biotinylated peroxidase complex method, using specific antibodies, and the ratio of the number of positive cells to total cells was determined. Expression of bFGF was detected in the nuclei of epidermal cells and fibroblasts in the early 0.5- to 1-hour phases and the late 24- to 144-hour phases. Expression of VEGF was detected in the cytoplasm of epidermal cells in the 24- to 144-hour phases. Immunoreactivity of both cytokines was detected 1 day post mortem and was especially well preserved in the fibroblasts. Time-dependent expression of both factors suggested that they would be useful markers for the determination of wound age. However, bFGF should be superior to VEGF because of its earlier expression and because of its more persistent expression in dermal fibroblasts with increasing postmortem interval.     

Quantitative analysis of proinflammatory cytokines (IL-1beta, IL-6, TNF-alpha) in human skin wounds

Proinflammatory cytokines play an important role in the mediation of inflammation and trauma. They could be useful for the determination of vitality and wound age. In the present study, 144 human skin wounds due to sharp force were investigated. The material was collected during operations (N=96) and postmortem examinations (N=48). The wound age varied from several seconds or minutes to 9 days. Control skin was available in each individual. The tissue specimens were homogenized and extracted in a solution of PBS and protease inhibitors. Interleukin-1beta (IL-1beta), interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-alpha) were measured by quantitative ELISA analysis. Statistical evaluation was performed by the t-test using the quotients of levels (wound sample/control skin). In surgical specimens the cytokine levels revealed a clear tendency to increase with wound age. IL-1beta in early skin wounds (24 h, P<0.05). The quantitative analysis of proinflammatory cytokines in wound extracts can contribute to the determination of vitality and wound age, in particular in the very early post-traumatic interval (classic stab wounds).     

巨噬细胞在损伤修复过程中的作用及其法医学意义

损伤时间推定,一直是法医学领域研究的重要课题。为了寻找准确推定损伤时间的方法,本文综述了巨噬细胞在损伤修复过程中的作用机理、伤后巨噬细胞源性细胞因子的表达和巨噬细胞吞噬物的演化与损伤时间的关系。认为进一步研究巨噬细胞在损伤修复中的特征性变化,有望成为推定损伤时间的方法之一。