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。     

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).     

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.     

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。     

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.     

The time-dependent expression of fibronectin,MRP8, MRP14 and defensin in surgically treated human skin wounds

Fibronectin, MRP8, MRP14 and defensin were detected immunohistochemically in 46 surgically treated, fresh (hours old) human wounds and in wounds of 13 individuals who died immediately from fatal trauma (airplane crashes or train rollovers). In immediate fatal trauma, it was not possible to detect fibronectin outside of bleeding areas nor could inflammatory cells be visualized in the interstitium using MRP8, MRP14, or defensin antibodies. Fibronectin staining could be regularly demonstrated in wounds at least 20 min-old. Granulocytic infiltrates limited to the perivasal space could be detected 20-30 min after infliction of the wound expressing MRP8, MRP14 and defensin. It was also possible to detect fibronectin networks and MRP8-, MRP14-, and defensin-positive granulocytes and macrophages in particular wounds up to 30 days-old. No differences between the expression of MRP8 and MRP14 could be demonstrated in the wounds, the majority of which were only several hours old. As wound age increased, the number of defensin-positive granulocytes detected decreased. The immunohistochemical detection of fibronectin is a useful way to demonstrate vitality in fresh wounds, beginning about 20-30 min post-trauma. However, detection of MRP8, MRP14 and defensin provides no advantage over the routine histological detection of granulocytes and macrophages in wounds under 1-2 days old.     

电击死兔骨骼肌及心肌HSP70 mRNA和c-fos mRNA表达

目的 研究电击死兔骨骼肌与心肌HSP70 mRNA和c-fos mRNA-表达变化。探究生前电击与死后电击的鉴别方法。方法 15只新西兰兔,随机分电击死组、死后电击组和对照组,每组5只,用荧光RT-PCR技术检测骨骼肌与心肌热休克蛋白70（HSP70） mRNA与c-fos mRNA表达水平,对所得结果进行统计学分析。结果 生前电击兔骨骼肌及心肌HSP70 mRNA与c-fos mRNA表达高于死后即刻电击者（P〈0．05）。结论 检测骨骼肌及心肌HSP70 mRNA与c-fos mRNA表达变化有助于于生前电击与死后电击的鉴别。     

大鼠脑损伤后COX-2表达变化的时间规律性研究

目的探讨大鼠脑损伤后环氧合酶2(COX-2)在神经元、神经胶质细胞中表达变化的时间规律性。方法以冲击应力σd为355.09kPa致大鼠脑损伤后,于不同时间段分别应用原位杂交、免疫组化、免疫组化双染色技术检测COX-2mRNA和蛋白的表达强度,用图像分析系统测定阳性反应物平均灰度,进行统计学处理。结果正常对照组COX-2mRNA和蛋白弱表达,伤后15min开始表达呈增强趋势,分别于伤后1,2d,表达达到峰值,平均灰度值分别为126.38±1.36、124.77±3.20,与对照组、邻近上组比较均具有显著性差异(P<0.05),于伤后3,4d,表达达到另一峰值,平均灰度值分别为127.18±1.96、120.14±3.52,并维持高水平表达分别至伤后7,15d,平均灰度值分别为110.03±2.61、111.27±2.83,与对照组比较具有显著性差异(P<0.05)。阳性细胞多为神经元。结论脑损伤后COX-2mRNA及蛋白的表达具有时间规律性,可作为法医学推断脑损伤形成时间的指标。     

脑损伤后COX-1和COX-2的表达

环加氧酶(cyclooxygenase,COX)是催化花生四烯酸(arachidonic,AA)合成前列腺素(prostaglandin,PG)的限速酶。后者在调节有丝分裂、凋亡、血管生成、血流动力学、继发性脑损伤及炎症反应等过程中发挥重要作用。COX有两种亚型:COX-1和COX-2。近年来研究证实,COX-1和COX-2在脑损伤过程中扮演了重要的角色。     

大鼠脊髓挫伤后BDNF表达的实验性研究

目的探讨大鼠脊髓挫伤后脑源性神经营养因子(BDNF)在脊髓内的表达变化规律。方法建立大鼠脊髓挫伤模型,以正常脊髓组织为对照,采用RT-PCR和免疫组化SABC法对伤后即刻、1h、3h、6h、12h、1d、3d、5d、7d大鼠脊髓组织中的BDNF和BDNF mRNA进行检测,并对所得数据进行统计学分析。结果正常大鼠脊髓组织细胞内有低水平的BDNF mRNA表达和少量BDNF阳性染色细胞,BDNF mRNA和BDNF的积分光密度(IOD)值分别为45.83±3.545、20286.225±2094.955,BDNF阳性细胞数为16.50±3.391;伤后6~12h,BDNF mRNA和BDNF呈升高趋势,5d达高峰,二者的IOD值及阳性细胞数分别为795.83±112.55、54272.143±2704.239和158.17±12.287。伤后7d,BDNF mRNA和BDNF的IOD值及阳性细胞数分别为655.17±80.871、42249.928±809.391和100.17±5.529。各组之间比较,其差异具有统计学意义(P<0.05)。BDNF免疫阳性细胞在损伤早期主要是脊髓神经元和少量星形胶质细胞,后期则以小胶质细胞为主。结论大鼠脊髓挫伤后,脊髓组织细胞中的BDNF及其mRNA增多,并随伤后时间呈现一定规律性变化。     

The application of histochemical methods to the age evaluation of skin wounds: experimental study in rabbits.

Enzyme histochemical methods allow determination of wound age, especially in the range of a few hours, and are used to distinguish between postmortem and antemortem skin wounds. The methods are based on the determination of the presence and changes of the enzyme reaction in the wound area. Increased activity of nonspecific esterases was observed approximately 1 hour after wounding and was followed by an increase in adenosine triphosphatase at approximately 2 hours and alkaline phosphatase at approximately 3.5 hours. Maximum enzyme activity was reached for nonspecific esterases at 24 hours, for adenosine triphosphatase at 20 hours, and for alkaline phosphatase at 32 hours after wounding.     

小鼠皮肤切创IL-10和IL-4的表达及其与损伤时间关系

目的　探讨IL 10、IL 4在小鼠皮肤切创愈合过程中的表达变化规律及其与损伤时间的关系。方法　应用免疫组织化学及图像分析技术 ,观察实验小鼠不同时程的生前伤 ( 0 5～ 168h)及死后伤 ( 1～ 6h)皮肤创伤局部IL 10、IL 4的表达情况。结果　生前伤 ,IL 10在伤后 1～ 3h阳性反应逐渐增强 ,3h达峰值 ,2 4h降至较低水平 ,伤后 48h再次升高 ,72h又达新峰值 ,其阳性表达部位主要在表皮细胞及单核 /巨噬细胞 ;IL 4于伤后 2 4h出现明显阳性反应 ,96h表达水平达峰值 ,168h仍维持在较高水平 ,其阳性细胞主要为创伤局部的成纤维细胞。死后伤 ,IL 10仅于死后 1～ 3h呈阳性染色 ,IL 4未见阳性染色。结论　IL 10、IL 4在小鼠皮肤切创愈合过程中的表达呈现一定的时序性变化。     

小鼠皮肤切创愈合过程中Ⅱ型大麻素受体的表达

目的观察皮肤切创愈合过程中CB2R表达变化的时问规律性。方法 健康小鼠50只,随机分为10组,建立皮肤切创模型,应用免疫组织化学技术及Westernbloting方法检测切创后不同时间段小鼠背部正中皮肤CB2R的表达。结果免疫组织化学结果显示,对照组CB2R表达于表皮、毛囊、皮脂腺、皮肌层、血管平滑肌、神经纤维外膜及神经纤维束束膜;伤后6h损伤区及周边区多核粒细胞少量表达CB2R,12～24h以单个核细胞阳性表达为主,3d以单个核细胞和梭形成纤维细胞表达为主,5～14d以梭形成纤维细胞为主。CB2R阳性细胞率于0h～3d逐渐升高,5d达最高峰,随后逐渐下降。经Westernblotting检测显示,对照及各个损伤时间段都有CB2R阳性条带,其中5d为CB2R表达高峰。结论小鼠皮肤切创愈合过程中,CB2R于损伤区及周边区多核粒细胞、单个核细胞、梭形成纤维细胞中表达,并具有规律性,提示CB2R可能参与皮肤损伤愈合,并可用于皮肤损伤时间的推断。     

无电流斑电击死兔骨骼肌il-6mRNA表达研究

目的探讨生前电击与死后电击的鉴别方法及电流通路的推断方法。方法15只新西兰兔，随机分为3组，每组5只，即电击死组、死后电击组、对照组。电击死组，用220V交流电的两极分别连接实验动物的左后肢与右前肢，通电致死。死后电击组，从耳缘静脉注射50ml空气致死，于死后即刻用220V交流电的两极分别连接实验动物的左后肢与右前肢通电3min。对照组直接从耳缘静脉注射50ml空气致死，不进行电击。用荧光RT—PCR技术检测骨骼肌白介素6信使核糖核酸（il-6mRNA）表达水平，所得结果进行统计学分析。结果电击死兔骨骼肌il-6mRNA水平远高于死后即刻电击者（P〈0．05）；电击死兔对称肢体中通电肢体骨骼肌il-6mRNA水平远高于非通电肢体（P〈0．05）。结论骨骼肌il-6mRNA表达变化可用于生前电击与死后电击的鉴别；机体对称部位骨骼肌il-6mRNA表达差异有助于推断电流通路。     

大鼠脑挫伤后脑组织COX-1/COX-2的表达

目的　观察脑损伤后COX 1和COX 2蛋白表达及其时序性变化 ,探讨脑损伤的分子机制及法医学脑损伤时间推断。方法　以自由落体撞击雄性SD大鼠右顶叶制备脑挫伤模型 ,用免疫组织化学SP法处理脑组织检材 ,观察不同时间 ( 1、 3、 5、 7、 14d)脑组织COX 1/COX 2蛋白的表达情况。结果　正常及手术对照组大鼠 ,脑组织内有低水平的COX 1/COX 2表达 ;脑挫伤后 1～ 5d ,大鼠脑组织内COX 1表达逐渐增加 ,14d时仍维持在高表达水平 ;脑挫伤后 1～ 3d ,大鼠脑组织皮质内COX 2表达逐渐增加 ,1d时海马COX 2表达达高峰。结论　脑挫伤后可诱导COX 1/COX 2蛋白在脑内表达 ,并呈现出时序性变化。     

大鼠皮肤挫裂创细胞间粘附分子-1的表达

目的 观察大鼠皮肤钝器伤后细胞间粘附分子-1(ICAM-1)表达的变化规律。方法 应用免疫组化方法,观察大鼠皮肤钝器伤后1h、3h、6h、12h、1d、3d、5d、7d、9d ICAM-1的表达情况,并用MIAS图像分析系统进行图像分析。结果 正常对照组大鼠皮肤有低水平ICAM-1表达,钝器伤后ICAM-1表达增加,伤后7d达峰值,伤后9d开始下降。结论 皮肤钝器伤可诱导ICAM-1表达增加,其时序性变化可望作为一种客观指标用于法医学损伤时间的推断。     

小鼠皮肤切创愈合过程中p-JNK变化及其与时间的相关性

目的 探讨小鼠皮肤切创愈合过程中损伤区磷酸化JNK（p-JNK）的变化及不同损伤时间p-JNK的变化规律。方法 应用免疫组织化学和Westernblot方法检测小鼠皮肤切创后各个时间段p-JNK的变化情况。结果 正常组织中有少量p-JNK阳性着色。伤后3～12h损伤区p-JNK阳性着色主要在中性粒细胞,1～5dp-JNK阳性着色主要为单核细胞和成纤维细胞,7～14dp-JNK阳性着色以成纤维细胞为主。阳性细胞率3h～1d逐渐增高,1d达到峰值,3～5d有所下降,7d阳性细胞率达第二峰值。10～14d逐渐降低。Westernblot显示各个时间段均有p-JNK的阳性条带,其中12h和3d为p-JNK含量的2个高峰。结论 小鼠皮肤切创愈合过程中p-JNK在损伤区对诱导中性粒细胞、单核细胞和成纤维细胞的凋亡起非常重要的作用。同时P-JNK的规律性变化可用于损伤时间推断。     

The macro- and micromorphological signs of the edge of stabbing-cutting weapons in skin wounds

110 stab-cut skin wounds in 34 dead bodies as well as 38 stab-cut instruments were studied. Three morphologic types of traces left by blade edges of stab-cut instruments, i.e. puncture, microrupture and microcut, were established. Gross and micromorphology of each of these traces depends on the properties of blade edges of stab-cut instruments.     

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。     

Characteristics of fibrin formation in stab wounds of the skin, determined by scanning electron microscopy

In an investigation on fibrin formation in skin cut wounds on guinea pigs using scanning electron microscopy, it was established that immediately after the infliction of cuts on live animals, a fine, netlike fiber structure of fibrin forms that gradually covers the entire wounded surface. In the period early after the cuts blood-forming elements attach to the fibrin net through numerous fine fibrin fibers, which incorporate a great number of thrombocytes. Postmortem investigations of these wounds showed that the fibrin net formed preserves its structure. It was also established that a fibrin net forms over skin wounds that were inflicted at different periods after death. In the wounds in the early periods after death, the fibrin net formed was very similar to the one established on wounds inflicted on living animals. Our investigation describes some peculiar characteristics of the fibrin net formed in living animals; there is a fine fiberlike net and the quantity is definitely larger. These characteristics permit the establishment of whether the wounds occurred before death and how much time has lapsed since then.