It is generally accepted that nuclei degrade in developing hair shafts but the point at which such occurs has not been investigated. The fate of mitochondria in the keratinizing hair shaft has been less clear. This study uses transmission electron microscopy to investigate when nuclei and mitochondria are no longer visible in the developing hair shaft. Serial sections were obtained from anagen head hairs absent follicles in order to determine the sequence of degradation of nuclei and mitochondria in the hair shaft by starting at the root bulb and proceeding toward the hair tip. It was demonstrated that nuclei and mitochondria become invisible in the keratinizing hair shaft at about the same time. This was found to occur fairly early in the process at the level of the hair shaft where the hair cuticle becomes permanent.

Although serial killings are relatively rare, they can be the cause of a great deal of anxiety while the killer remains at-large. Despite the fact that the motivations for serial killings are typically quite complex, the psychological analysis of a serial killer can provide valuable insight into how and why certain individuals become serial killers. Such knowledge may be instrumental in preventing future serial killings or in solving ongoing cases. In certain serial killings, the various incidents have a variety of similar features. Identification of similarities between separate homicidal incidents is necessary to recognize that a serial killer may be actively killing. In this report, the authors present a group of serial killings involving three prostitutes who were shot to death over a 3-month period. Scene and autopsy findings, including the unusual finding of postmortem enucleation of the eyes, led investigators to recognize the serial nature of the homicides.

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.