A Comparison of Histomorphometric Data Collection Methods*

Abstract: Although many variables that skeletal biologists examine have been standardized, the actual techniques used to collect these data from bone thin sections vary. This project compares different methods of obtaining data (relative cortical area values) for histomorphometric research. One visual and three digital methods of histomorphometric data collection are compared: (i) Merz microscopic eyepiece counting reticule, (ii) flatbed scanner, (iii) overlaying multiple images of a thin section, and (iv) digital SLR camera with macro settings. The discussion includes a comparison of usability factors such as cost, time, user‐experience, and ease‐of‐use, which vary for each method. Values from the different methods are compared using ANOVA tests to evaluate inter‐method, inter‐observer, and intra‐observer variability. Intra‐observer error was greater for the microscopic method, although the error values are concomitant with experience. We found no statistically significant differences between the four methods examined, but certain caveats must be addressed when these methods are used.     

Laser microdissection separation of pure spermatozoa from epithelial cells for short tandem repeat analysis

Short tandem repeat (STR) analysis is a valuable tool in identifying the source of biological stains, particularly from the investigation of sexual assault crimes. Difficulties in analysis arise primarily in the interpretation of mixed genotypes when cell separation of the sexual assailant's sperm from the victim's cells is incomplete. The forensic community continues to seek improvements in cell separation methods from mixtures for DNA typing. The feasibility of applying laser microdissection (LMD) technology to precisely separate sexual assault cell mixtures by visual inspection coupled with laser dissection was assessed through three experiments. First, various histological stains were evaluated for use with LMD and DNA analysis. Second, different DNA isolation methods were evaluated on LMD-collected cells. Finally, STR analysis was performed on LMD-separated sperm cells from mixtures of semen and female buccal epithelial cells. The results indicated (a) hematoxylin/eosin staining performed best in its ability to differentiate sperm and epithelial cells while exhibiting the least negative effect on further downstream analysis; (b) both QIAamp and Lyse-N-Go methods were useful for recovery of DNA from LMD-collected sperm cells; and (c) LMD separation provided clear STR profiles of the male donor with the absence of any additional alleles from the female donor. This report describes an efficient, low-manipulation LMD method for the efficient separation of spermatozoa from two-donor sperm/epithelial cell mixtures.     

论病理因素对笔迹的影响

人的书写活动,是极端复杂与微妙的。它是由脑、身、肩、臂、肘等多个器官联合、协调动作完成的,各部位发挥的作用不一样,各有各的机理、机制。在正常情况下,缺少任何一项就不能完成书写活动,而其中任何一项一旦发生病变,写出的字也要发生变化。研究这种变化的特点及成因,对笔迹鉴定很有裨益。     

大鼠闭合性脑损伤酯化银和白蛋白组织化学研究

目的 研究闭合性脑损伤立即死亡和伤后 15min至 5天的大鼠脑组织病理变化。方法 应用 HE染色法观察闭合性脑损伤的组织形态学变化。结果 伤后立即死亡组大鼠脑干、大脑和小脑大量神经元表现为皱缩 (Ⅰ型变 )和肿胀 (Ⅱ型变 ),脑干大片神经纤维波浪样变形;伤后 2～ 8h,出现神经元水肿和轴索肿胀明显;伤后 8～ 24h,出现轴索收缩球。之后,Ⅰ型变、Ⅱ型变和收缩球随存活时间延长而增多加重。伤后 4～ 5天,组织水肿减轻或消失,收缩球仍存在。酯化银染色观察,各种损伤性改变均较 H.E.染色更清晰。 ABC法,血浆 Al随伤后时间延长,从血管周围逐渐向周围扩散,并进入损伤的神经元和胶质细胞。结论 脑震荡性损伤改变呈冲击性、对冲性和向心性分布。     

APM染色法在羊水栓塞诊断中的应用价值

目的　探讨APM染色法在羊水栓塞 (AFE)病理学诊断中的应用价值。方法　采用APM染色法对 1988年至 2 0 0 1年确诊为AFE的 19例病例 (AFE组 )和羊水吸入性肺炎的胎儿 3例 (阳性对照组 )、其它死因的 10例产妇 (阴性对照组 )重新进行染色和组织学检查 ,对其检验结果进行比较分析。结果　阳性组全部检出羊水成分 ,阴性组部分病例检出羊水成分 ,发现漏诊、误诊各 1例。与HE染色相比较 ,APM染色能提高角化上皮和粘液的检出率。结论　APM染色能提高羊水成分的检出率 ,有助于提高AFE诊断的准确性 ,可用于AFE病理学诊断。     

The utility of histology in assessing the cause of death in medico-legal autopsies in selected trauma deaths: Suspension-, immersion-, fire-, and traffic-related

The goal of a medico-legal autopsy is primarily to determine the cause and manner of death. To this end, the pathologist often uses auxiliary analyses, including histology. However, the utility of routine histology in all medico-legal autopsies is unknown. Earlier studies on the utility of routine histology have shown inconsistent effects, with some studies recommending it and others rejecting it. To study the degree to which histology informs on the underlying cause of death, we sent autopsy reports from suspension-, immersion-, fire-, and traffic-related deaths to senior board-certified forensic pathologists and had them assess the cause of death, first without knowledge of the histological findings and then with knowledge thereof. Fifty cases were identified in each of four subgroups: fire-, immersion-, suspension-, and traffic-related deaths. The autopsy reports were anonymized, and the histological findings and conclusions were removed. Two board-certified forensic pathologists independently reviewed the reports in each subgroup and assessed the manner and underlying cause of death (including their certainty of this assessment on a five-level scale) with and without access to histological findings. The probability of changing the underlying cause of death posthistology was low in all study groups. There was a slight increase in the degree of certainty posthistology in cases where the underlying cause of death was not changed, but only when the antehistology certainty was low. Our results suggest that histology does not meaningfully inform on the underlying cause of death in suspension-, immersion-, fire-, and traffic-related deaths except when antehistology certainty is low.     

Death Caused by Hepatodiaphragmatic Interposition of the Colon

Hepatodiaphragmatic interposition of the colon is a rare, usually asymptomatic, anomaly and is typically an incidental radiologic finding. There are few cases in the literature describing the symptomatic form of the condition, known as Chilaiditi syndrome. In some cases, it may be accompanied by various severe complications. If symptoms are present, usually conservative treatment is given. However, conservative treatment only addresses the symptoms but does not prevent their recurrence and possible complications. Our present report shows that this anomaly may not only cause symptoms, but may also progress and cause severe complications, in our case—megacolon leading to right heart failure and, ultimately, death. To date, however, there have been no literature reports of death caused by colonic interposition. Therefore, it is important to draw attention to the importance of this anomaly and its appropriate diagnosis and treatment to ensure the most favorable patient outcomes.     

A Retrospective Study of the Investigation of Homicidal Childhood Asphyxial Deaths

As one of the leading causes of traumatic deaths in newborns, infants, and young children, there is no anatomic or microscopic feature that is pathognomonic for asphyxial deaths. Instead, pathologists rely on investigation information, including confessions and/or witness statements, and potential evidence at the scene. Twenty cases of homicidal newborn, infant, and young children asphyxial deaths were reviewed, which included death and police investigation reports and autopsy reports, as well as histology slides of lung sections. This series of homicidal asphyxial deaths highlight that, in a vast majority of such cases, the final cause and manner of death rulings are dependent on confession by the perpetrator. Furthermore, this series highlights the possible role of histology to help forensic pathologists better certify asphyxial deaths. Finally, this series emphasizes important investigation points and considerations at autopsy during the investigation of asphyxial deaths in newborns, infants, and young children.     

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.     

A Method to Interpolate Osteon Volume Designed for Histological Age Estimation Research

Aging adult skeletal material is a crucial component of building the biological profile of unknown skeletal remains, but many macro- and microscopic methods have challenges regarding accuracy, precision, and replicability. This study developed a volumetric method to visualize and quantify histological remodeling events in three dimensions, using a two-dimensional serialized approach that applied circular polarizing microscopy and geographic information systems protocols. This approach was designed as a tool to extend current histological aging methodologies. Three serial transverse sections were obtained from a human femoral midshaft. A total sample size of 6847 complete osteons from the three sections was identified; 1229 osteons connected between all sections. The volume of all connected osteons was interpolated using ArcGIS area calculations and truncated cone geometric functions. Each section was divided into octants, and two random samples of 100 and of 30 connected osteons from each octant were generated. Osteon volume was compared between the octants for each random sample using ANOVA. Results indicated that the medial aspect had relative uniformity in osteon volume, whereas the lateral aspect showed high variability. The anterolateral–lateral octant had significantly smaller osteon volume, whereas the posterior–posterolateral octant had significantly larger osteon volume. Results also indicated that a minimum of 100 osteons is statistically more robust and more representative of normal osteon distribution and volume; the use of 30 osteons is insufficient. This research has demonstrated that osteon volume can be interpolated using spatial geometry and GIS applications and may be a tool to incorporate into adult age-at-death estimation techniques.