大鼠机械性脑干损伤早期延脑网状结构的超微病理研究

目的　探讨脑干损伤早期延脑网状结构的超微病理变化。方法　将实验大鼠分为创伤组和对照组,透射电镜观察大鼠机械性脑干损伤早期（１０ｍｉｎ,０ ．５ｈ,１ｈ ,３ｈ） 延脑网状结构的超微病理变化。结果　脑干损伤１０ｍｉｎ 即可见神经微丝（ｎｅｕｒｏｆｉｌａｍｅｎｔ, ＮＦ） 排列紊乱、疏密不均,ＮＦ 臂的缺失,髓鞘层面分离,轴膜内皱,与髓鞘间形成空隙,微血管周围基质密度降低以及线粒体肿胀等超微病变。脑干伤后存活时间延长,上述病变更为显著。本文就上述超微病变的形成机制及病理学意义进行了探讨。结论　脑干机械性损伤能够明显引起延脑网状结构的超微病理学变化,并增加个体快速死亡和免疫组化染色的易感性     

家兔死后红细胞内钾钠离子含量与死亡时间的关系

研究了40只家兔死后不同时间心血红细胞内钾钠离子含量变化及红细胞膜Na+－K+－ATP酶活性。发现红细胞内钾离子含量随死亡时间增加呈线性下降（r=-0．829,P＜0．025）。在死后0－48小时,红细胞内钾离子含量与死亡时间显著相关。红细胞膜Na+－K+－ATP酶活性在死后48小时无显著变化。     

Ultrastructural pathology of the alveolar apparatus in experimental drowning

Investigations were carried out on anaesthetized rats which by a tracheotomy tube actively aspirated liquids of different osmolarities covering a range from tap water to 2.9% NaCl solution. In every range of osmolarity, the ultrastructural alterations show areolar limitations and different stages of development. In freshwater the influx of liquid causes a hypoxemic-dysoric alveolose with diffuse of pulvinate oedematous swellings of all compartments of the blood-gas-barrier, cytolysis, karyolysis, membrane desintegration, hydropic alterations of the (cell) organelles, dilatation of the drainage tracts of the alveolar interstitium. Vesicular transformation caused by a dilatation of the pinocytotic system ending in endothelial and epithelial vesiculation. Salt-water drowning leads to a hypoxemic alveolose with a marked compaction of the matrix. The epithelium shows many alterations of the surface, numerous protrusions, constrictions and expose of the basement membrane (villous transformation). Erythrocyte sludge and thorn-apple-shaped erythrocytes are found in the capillaries. Application of electron microscopy in the diagnosis of drowning allows a more reliable classification and, correspondingly, decisive improvements of the reliability of lightmicroscopical findings.     

人体血液体外电击致血细胞穿孔的扫描电镜观察

目的探讨血细胞体外电击时细胞膜的结构变化。方法对成人血液分别分组通过220V交流电电击5,10,20,30s和1min后,用扫描电镜观察血细胞膜的变化。结果电击后,即可以观察到红细胞与白细胞的细胞膜穿孔,其中红细胞穿孔可为一个或多个,形状多为圆形或卵圆形,白细胞穿孔则为多个,呈筛网状;穿孔细胞数随电击时间延长而增多;电击5s时为6%左右,以后逐渐增加,至电击1min时,穿孔细胞数可达40%左右。结论电流作用可以使血细胞膜发生穿孔,穿孔细胞数随通电时间延长而增多。     

Assessment of Wear‐Related Features of the Kerf Wall from Saw Marks in Bone*†

Abstract: Analyses of saw marks in bone may yield important information about the class characteristics of saws used in postmortem dismemberments, yet little research has been directed at identifying saws’ individualizing characteristics. This study adds to existing saw mark analysis methodologies by examining wear‐related features of kerf walls using light‐ and environmental scanning electron microscopy. A crosscut saw and hacksaw were used to create sequences of 30 cuts in bone; these sequences reveal patterns of progressive loss of fine details of kerf wall morphology with increasing saw blade wear, because of the rounding of sharp points and edges. Nevertheless, diagnostic kerf wall features used to establish class characteristics persist despite these wear‐related changes. Unsuccessful attempts at statistical analysis of wear‐related changes, based on striae width and density, suggest these patterns are not readily quantifiable. Additionally, despite the scanning electron microscope’s superior imaging capabilities, it provided few practical, methodological gains over traditional light microscopy.     

SEM analysis of red blood cells in aged human bloodstains.

Mammal red blood cells (RBC) in bloodstains have been previously detected by light microscopy on stone tools from as early as 100,000 +/- 25,000 years ago. In order to evaluate the degree of morphological preservation of erythrocytes in bloodstains, an accidental human blood smear on white chert and several experimental bloodstains on hard substrates (the same stone-white chert; another type of stone-graywacke; a non-stone support-stainless steel), were stored in a room, in non-sterile and fluctuating conditions, for lengths of time ranging from 3 to 18 months. Afterwards, the specimens were coated with gold and examined by a Cambridge Stereoscan 120 scanning electron microscope. Results revealed a high preservation of RBC integrity, with the maintenance of several discocytary shapes, a low tendency to echinocytosis and a frequent appearance of a moon-like erythrocytary shape in the thinner areas of the bloodstains.     

大鼠视神经横断伤后视网膜形态学改变及Bcl-2/Bax表达

目的观察大鼠视神经横断伤后,视网膜细胞(RGCs)形态学变化、Bcl-2/Bax蛋白不同时间的表达变化,并探讨其与视神经损伤经过时间的关系。方法采用大鼠球后视神经横断伤动物模型,用Bcl-2和Bax免疫组织化学和HE染色方法观察伤后不同时间RGCs的动态变化。应用图像分析技术,对Bcl-2及Bax免疫反应阳性细胞进行统计学分析。结果视神经横断伤后RGCs数目严重下降,2周内RGCs快速减少,2周以后缓慢减少;伤后Bcl-2、Bax表达随时间不同程度的增加,Bax对损伤反应较Bcl-2稍晚,两者表达均呈现先升后降的趋势,并维持一定的时间。Bcl-2/Bax蛋白表达比率与RGCs存活数目有一定的相关性。结论视神经横断伤后Bcl-2和Bax的表达在伤后不同时间呈现一定的规律性变化,可为损伤时间的推断提供一定依据。     

Fatal postpartum coronary artery dissection. A light- and electron-microscope study

A case report of fatal spontaneous dissection of the distal left circumflex coronary artery in a 37-year-old postpartum female is presented. Samples of arterial wall from this patient and from six other postpartum females who died of unrelated causes were examined by light (LM), scanning electron (SEM), and transmission electron (TEM) microscopy. Morphological changes to explain the recognized predisposition of this cohort to coronary artery dissection were sought. The origin of the dissection was demonstrated by serial LM sections to be in midmedia with no intimal extension. The predominant plane of dissection was the junction of media and adventitia. Sarcolemmal blebbing and accumulation of amorphous intercellular material were demonstrated at the dissection site by SEM but were not seen elsewhere in the affected heart or in any of the six control hearts. These changes could not be distinguished by TEM from prolonged ischemic injury. There was no accumulation of eosinophilic leukocytes in the vessel wall or adventitia, and adventitial mast cells were not consistently more frequent than in the controls. No increase of stainable intramural mucopolysaccharides was seen in the fatal case. The results indicated no generalized arterial change in postpartum coronary arteries to account for the increased frequency of dissection. A focal degenerative process remains the most likely possibility.     

Destruction of intracerebrally applied red blood cells in cervical lymph nodes. Experimental investigations

In rabbits, intracerebrally applied erythrocytes can move with the cerebrospinal fluid along connecting pathways between the subarachnoid space and the cervical lymph nodes. This study compares the time dependency for the degradation of intracerebrally injected erythrocytes in the brain as well as in the cervical lymph nodes. Rabbits were killed at various predetermined intervals after the intracerebral erythrocyte injection. Microscopic and histologic examination of the brain and the cervical lymph nodes revealed the following findings: (1) Erythrophages first appeared in the brain 24 h after the injection; siderophages, 4 days after the injection. Siderophages were still demonstrable at the conclusion of the study, i.e. 240 days after the injection. (2) In the cervical lymph nodes erythrophages were first observed 1 h after the injection; siderophages, 9 h after the injection. Only isolated erythrophages and siderophages were found in the lymph nodes 12 days after intracerebral injection of red blood cells. Later on no erythrocytes or siderophages were observed in the lymph nodes. The findings indicate that non-phagocytized red blood cells arriving at the lymph nodes were ingested by local macrophages. The extremely rapid ingestion and digestion of the red blood cells by lymph node macrophages as well as the possible reasons were discussed.     

大鼠电击死心脑肺及皮肤超微结构的改变

目的 观察电击致死大鼠的心、脑、肺、皮肤超微结构形态学改变，寻找电击死的法医学鉴定依据。方法 大鼠12只，其中电击致死6只，另6只对照；取心、脑、肺、皮肤，用戊二醛固定、锇酸染色后透射电镜观察。结果 所取组织细胞均见明显细胞凋亡样改变，其中红细胞肿胀变形，充填整个毛细血管管腔。结论 心、脑、肺、皮肤组织细胞与血管内皮细胞的超微结构形态改变对鉴定电流死有参考价值。     

The ultrastructure of tissue attached to telogen hair roots

Most tissues encountered in forensic biology laboratories have been previously characterized with electron microscopy due to their medical importance. Anagen hair root cells, epithelial cells, erythrocytes, neutrophils, osteocytes, and spermatozoa have received considerable research attention at the ultrastructural level. There is no literature indicating that cells attached to removed telogen hair roots have been characterized with transmission electron microscopy. Nonetheless, telogen hairs are a frequent submission item to forensic laboratories for DNA typing. The amount of tissue attached to a telogen hair root usually determines whether that hair is suitable for nuclear DNA typing methods or mitochondrial DNA typing methods. This study used transmission and scanning electron microscopy to characterize the tissues found in three commonly occurring telogen hair root forms. The tissues were found to consist of keratinized remnant follicle, nonnucleated epithelial cells, nucleated epithelial cells, and trichilemmal keratin. These findings were consistent with the known principles of hair follicle regression. The recognition of the root structures that contain these specific tissue types may assist in the DNA typing of telogen hairs inasmuch as the quality of tissue present may be more important than the amounts of tissue present.     

大鼠急性八角莲中毒的组织病理学变化

目的观察大鼠急性八角莲中毒后主要器官的病理形态学改变,探讨急性八角莲中毒的作用机制及其对靶器官、靶组织的损伤影响。方法随机将40只SD大鼠,分为3个实验组(0.5、1.0和2.0倍LD50剂量的八角莲水煎剂灌胃)和1个对照组(1.0倍LD50剂量的生理盐水灌胃)。大鼠在八角莲急性染毒后14d处死,解剖取脑、心、肝、肺、肾,样品经组织病理学处理后,光镜和电镜下观察大鼠主要器官病理形态学改变。实验数据采用χ2检验进行统计学分析。结果光镜观察结果:神经元胞质疏松,大部分尼氏小体消失;心肌细胞肿胀,润盘及横纹结构消失;肝细胞水肿、气球样变;肾近曲小管上皮细胞肿胀,管腔内见蛋白质样红色淡染物质。电镜观察结果:神经元细胞膜及核膜结构破坏,胞质明显水肿,细胞器大多已破坏、消失。急性染毒后4组大鼠死亡率随着剂量的增加而增高(P0.05)。结论急性八角莲中毒可引起多器官病理形态学改变,其毒性作用与剂量呈正相关性,且主要靶组织、靶器官为脑(神经元)、心、肝和肾。     

How and why does the platelet count in postmortem blood change during the early postmortem interval?

We examined the changes in the early postmortem platelet count in postmortem blood and the reasons for these changes by counting the platelets, by performing in vitro hypostatic tests, by estimating the percentage of erythrocytes by volume in postmortem blood samples, by immunohistochemistry (anti-CD61, anti-fibrinogen), and by immunoelectron microscopy (anti-CD62, anti-CD63, anti-thrombospondin). The apparent initial increase in the platelet count in postmortem blood was found to be caused by hypostatic phenomena. The subsequent discontinuous decrease in the platelet count despite continuing hypostasis in the corpse can be explained in part by postmortem thrombolysis and the development of reversible platelet-platelet aggregates. The main point is, that changes in the postmortem blood environment cause potentially reversible adhesion of platelets to pre-adsorbed fibrinogen on erythrocytes. Thus the decrease in the number of platelets in postmortem blood is not attributable to postmortem clotting but to a decrease in the number of countable platelets in postmortem blood.     

Effects of anoxia on the isolated perfused rat heart: histological, histochemical and electron-microscopic observations

A study to evaluate hematoxylin-basic fuchsin-picric acid (HBFP) and some other conventional stains in the demonstration of early anoxic lesions of the perfused rat heart has been undertaken. The extent of the anoxic injury was readily demonstrable electron-microscopically and in semithin sections by light microscopy, and at 1.5--2 hours practically all myocardial cells showed irreversible changes. The HBFP method was unreliable, giving false positive and false negative results both in the control and anoxic specimens. No clear changes were seen in the four histochemical dehydrogenase reactions applied, whereas damaged myocytes lost some of their affinity to eosin. Contraction bands were frequently seen in the anoxic hearts stained by the phosphotungstic acid-hematoxylin method. However, their presence was not in a linear accordance with the extent of the lesion. The perfusion model is not directly comparable to the myocardial infarct caused, for example, by ligating the coronary artery but, however, the present results suggest the difficulty of demonstrating the very early anoxic myocardial lesion by means other than electron microscopy.     

Potential definition of the time of death from autolytic myocardial cells: a morphometric study

Morphometric methods and transmission electron microscopy were used to quantify modifications occurring in the mitochondria of dog myocardium during the first four hours of autolysis. Myocardial fragments were obtained from the outer free wall of the left ventricle, during anesthesia (control-zero) and at 15, 45, 120, and 240 min after cardiac arrest, maintaining the heart "in situ" at 22 degrees C. During the 240 min of autolysis, the main parameters evaluated showed: (a) a decrease in the number of mitochondria from 0.31 to 0.12 per micron 3 of cytoplasm. The decrease over the first 45 min reached 50% of the initial value; (b) an increase in mitochondrial volume, three times greater after the first 45 min (from 0.92 to 2.68 micron 3) and four times greater after 240 min (from 0.92 to 3.79 micron 3); (c) an increase in mitochondrial outer membrane surface area from 5.51 to 12.54 micron 2; (d) an increase in the surface area of individual mitochondria inner membrane and cristae from 27.60 to 56.96 micron 2. The progressive nature of the alterations and the difference in the numerically expressed values allow correlation with the time of somatic death. The authors emphasize the need for further studies in order to complement the present study.     

Studies on asphyxia: on the changes of the alveolar walls of rats in the hypoxic state

The morphological changes of the alveolar wall of adult rats in the hypoxic state were studied by light and electron microscopy. The remarkable findings were the appearance of a large amount of lamellar, lattice- and thread-like structures together with a massive homogeneous substance on the surface of the alveoli which seemed to be closely connected with each other and with the surface of the cells lining the alveolus, especially in the 5%-group. The appearance of the above-mentioned structures with the homogeneous substance is considered to be the reaction of lung tissue to the decreased content of oxygen in the inhaled gas.     

钾中毒致死家兔病理形态学变化

目的研究钾中毒致死家兔的尸体组织形态学变化特征,为钾中毒致死的法医学鉴定提供客观依据。方法采用浓度为0.3%和1%的氯化钾溶液,分别以全速和100滴/min的速度静脉输注家兔至其死亡,肉眼、光镜及透射电镜下观察尸体心、脑、肾形态学变化,比较两种不同输液方式下形态学变化的差异。结果输钾致死的家兔心脏显著扩张淤血,心肌呈缺血缺氧改变,心肌肌节长短不一,Z线变宽、聚集或消失;肾小球毛细血管收缩,包曼氏囊扩张,足突绒毛化、融合;脑组织中可见凋亡及吞噬现象。上述改变均以1%组为著。结论心脏及肾脏的一些形态学改变可作为钾中毒死亡法医学鉴定的重要依据。     

The state of brain ventricles and their ependima in different scenarios of traumatic blood loss

The objective of the present study was to evaluate the state of ependima and the subependimal layer of the brain ventricles after death from the traumatic blood loss and in the cases of the blood loss under conditions of acute alcoholic and narcotic intoxication. The methods used for this purpose included light and scanning electron microscopy. It was shown that in subjects who died from the traumatic blood loss during acute alcoholic and narcotic intoxication ependima showed the signs of progressive polymorphism and had extensive areas of discontinued cell layers. Neuropil contained numerous vacuoles and blood effusion sites. The surface of ependima exhibited pathological erythrocytes, agglomerations of detritus, and crystalloid structures. The blood loss during combined alcoholic and narcotic intoxication resulted in more pronounced alterations in the ventricular walls.     

实验性心脏震荡的法医病理学研究

本研究应用可产生稳定打击速度并可同时测定瞬间冲击速度及冲击力大小的机械式弹性拉力打击器，分别以６．７ｍ／ｓ及８．０ｍ／ｓ速度冲击大胸骨部心前区建立了心脏震荡动物模型，在左右心室压力及心电图监测下冲击后６０分钟进行尸体剖验检查，并应用多种组织化学染色、透射电镜技术、免疫组织化学染色以及硝酸镧示踪电镜技术对心肌组织学行系统性研究。结果表明：１．心前区受冲击瞬间左右心室内压力急骤升高，随即可恢复至正常水平。心电图在冲击后即刻表现为持续短暂的异常心律，逐渐恢复至正常心律。２．心脏血管麻痹性扩张，但宏观及微观均无损伤性所见。３．心肌超微结构有一定程度损害，心肝细胞膜破裂或通透性增高。本研究提示：心脏震荡者心脏宏观、微观无特殊改变，但超结构及心肌细胞膜轻度损害。     

失血死亡及休克早期心肌病理学研究

应用电镜,组织化学,免疫组化及形态计量分析等方法和技术,观察了失血致死和休克早期不同时间家兔心肌超微结构、琥珀酸脱氨酶（SDH）活性、肌红蛋白（Mb）脱失的变化特点。结果发现：失血致死和休克早期，不同时间兔心肌超微结构、SDH活性和Mb含量有不同程度的改变。病变程度随休克时间的延长而加重。本文还讨论了这些改变在法医学上的意义。