The judicial view of bitemarks within the United States Criminal Justice System.

When examining most traditional sciences a thorough review of the relevant primary literature is usually sufficient to provide the investigator with a sound insight into the discipline. Forensic science differs in this regard, as it is presented in two main arenas: the peer-reviewed forensic journals and the Courts of Law where testimony is proffered. Because of this duality of scientific assessment the following legal review is presented. The review analysed Appellate Court rulings from the United States and identified trends of objections to bitemark testimony. Nine major trends were identified within the cases assessed: bitemark evidence not sufficiently reliable or accepted, arguments regarding the uniqueness of the human dentition, constitutional arguments, inflammatory photographs, inaccuracy of techniques and errors in protocol, use of historical bitemarks and previous biting behavior, funds for defence witnesses and objections pertaining to witness credibility.

Advances in the diagnosis of wound vitality: a review.

The diagnosis of the vital origin of wounds in many cases remains an unsolved problem for the forensic pathologist. Practical experience enables the expert to diagnose the vital or postmortem origin of wounds on the basis of macroscopic examination. In some cases, optic microscopy is used to confirm the diagnosis. In many other cases, additional more sensitive and specific markers of vitality are required. In the past 50 years, comprehensive research on this topic has resulted in a better understanding of the acute inflammatory reaction. The development and application of sensitive and specific markers through research in the areas of histochemistry, enzymology, and biochemistry has provided a partial solution to the problems involved in wound vitality diagnosis. A review of this challenging area of forensic pathology, including an explanation of these methods and markers, is presented in this paper.

Human bites and the risk of human immunodeficiency virus transmission.

The risk of human immunodeficiency virus (HIV) transmission following a bite injury is important to many groups of people. The first are those who are likely to be bitten as an occupational risk, such as police officers and institutional staff. Another group are represented by the victims and perpetrators of crimes involving biting, both in attack and defense situations. The possibility of these bites transmitting a potentially fatal disease is of interest to the physicians who treat such patients and the legal system which may have to deal with the repercussions of such a transmission. Bite injuries represent 1% of all emergency department admissions in the United States, and human bites are the third most common following those of dogs and cats. The worldwide epidemic of HIV and acquired immunodeficiency syndrome (AIDS) continues, with >5 million new cases last year and affecting 1 in 100 sexually active adults. A review of the literature concerning human bites, HIV and AIDS, HIV in saliva, and case examples was performed to examine the current opinion regarding the transmission of HIV via this route. A bite from an HIV-seropositive individual that breaks the skin or is associated with a previous injury carries a risk of infection for the bitten individual.

Digital dental radiographic identification in the pediatric, mixed and permanent dentitions.

The purpose of this paper is to investigate the utility of digital dental radiographic superimposition in the various stages of development of the human dentition. Digital, computer assisted dental identification is a means of identification which allows the spatial relationships of the root and support structures of the teeth to be compared one to the other. The technique has not been tested in patients with developing dentitions. Dental radiographs from patients in the pediatric, mixed and permanent dentition stages of development, simulating "antemortem" and "postmortem" radiographs, were digitized using a flat field radiograph scanner. Anatomic features were used as points of comparison utilizing image editing software whereby anatomic sections were digitally cut from the antemortem image and compared to the same anatomic locations on the postmortem image to assess for points of concordance. The technique was applied to 25 cases within the primary dentition, 25 cases within the mixed dentition and 25 cases within the permanent dentition. Results showed that this was a viable technique within both the pediatric and permanent dentition although it was of little value within the mixed dentition.

A specimen positioning device for dental radiographic identification--image geometry considerations.

Preventative dental treatment has reduced caries incidence and thereby rendered dental identification, in caries-free individuals, more difficult. An alternate method comparing spatial relationships of dental structures in digitized superimposed antemortem and postmortem radiographs has been previously developed. This paper examined the limitations of this technique and demonstrates a positioning device suitable for reproducing antemortem radiographic image geometry. The paper also examined three specific aspects of image geometry namely horizontal angulation, vertical angulation and focal film distance. Deviations in horizontal angulations between antemortem and postmortem radiographs by as little as 5 degrees makes identification difficult. Changes in vertical angulation or focal-film distance had no affect. This procedure, and the positioning device used to accurately replicate antemortem image geometry is an economical, easy to use adjunct to current methods of dental identification.

A GTPase distinct from Ran is involved in nuclear protein import.

Signal-dependent transport of proteins into the nucleus is a multi-step process mediated by nuclear pore complexes and cytosolic transport factors. One of the cytosolic factors, Ran, is the only GTPase that has a characterized role in the nuclear import pathway. We have used a mutant form of Ran with altered nucleotide binding specificity to investigate whether any other GTPases are involved in nuclear protein import. D125N Ran (XTP-Ran) binds specifically to xanthosine triphosphate (XTP) and has a greatly reduced affinity for GTP, so it is no longer sensitive to inhibition by nonhydrolyzable analogues of GTP such as guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S). using in vitro transport assays, we have found that nuclear import supported by XTP-Ran is nevertheless inhibited by the addition of non-hydrolyzable GTP analogues. This in conjunction with the properties of the inhibitory effect indicates that at least one additional GTPase is involved in the import process. Initial characterization suggests that the inhibited GTPase plays a direct role in protein import and could be a component of the nuclear pore complex.

Taking from the cytoplasm and giving to the pore: soluble transport factors in nuclear protein import.

The past year has seen the publication of a number of papers describing the identification of cytosolic factors involved in import of proteins to the nucleus. Although, at first glance, this gives the impression that the study of nuclear transport has become extremely complicated, these factors in fact form a relatively small group of proteins that have been given different names. Characterization of these proteins is improving understanding of the nuclear import process and provides a starting point for further investigation of the steps that occur at the nuclear pore complex.

DNA analysis of dental pulp to link incinerated remains of homicide victim to crime scene.

Teeth endure postmortem degradation and extreme changes in ambient temperature and pressure better than most human tissues. This ability to resist deterioration allows the teeth to be studied as a method of establishing the identity of a decedent. Additionally, dental hard tissues, and in some instances soft tissues, may provide investigators with other sources of forensic data. In this case, a female homicide victim was transported to a location where her remains were burned. The high temperatures of a gasoline fire effectively incinerated the body precluding deoxyribonucleic acid (DNA) analysis from conventional sites. However, most of the teeth survived the conflagration. They were used to identify the victim. Additionally, the dental pulps were found to be an excellent source of high molecular weight genomic DNA. This proved to be an effective method to link the victim's body to biological evidence recovered from the site of the murder.

Tpr, a large coiled coil protein whose amino terminus is involved in activation of oncogenic kinases, is localized to the cytoplasmic surface of the nuclear pore complex.

From a panel of monoclonal antibodies raised against fractions of rat liver nuclear envelopes (NEs), we have identified an antibody, RL30, which reacts with novel nuclear pore complex (NPC) antigens that are not O-glycosylated. By immunofluorescence staining of cultured cells, RL30 reacts exclusively with the NE in a punctate pattern that largely coincides with that of identified NPC proteins. RL30 labels only the cytoplasmic surface of the NPC in immunogold electron microscopy, predominantly in peripheral regions nearby the cytoplasmic ring. In immunoblots of isolated rat liver NEs and cultured rat cells, RL30 recognizes a 265-kD band, as well as a series of 175-265-kD bands in rat liver NEs that are likely to be proteolytic products of p265. Sequencing of peptides from the 175- and 265-kD RL30 antigens of rat liver revealed that they are both closely related to human Tpr, a protein whose amino-terminal 150-250 amino acids appear in oncogenic fusions with the kinase domains of the met, trk, and raf protooncogenes. We found that in vitro translation of human Tpr mRNA yields a major 265-kD band. Considered together, these data indicate that the 265-kD RL30 antigen in the NPC is the rat homologue of Tpr. Interestingly, Tpr contains an exceptionally long predicted coiled coil domain (approximately 1600 amino acids). The localization and predicted structure of Tpr suggest that it is a component of the cytoplasmic fibrils of the NPC implicated in nuclear protein import. Immunofluorescence microscopy shows that during NPC reassembly at the end of mitosis, Tpr becomes concentrated at the NE significantly later than O-linked glycoproteins, including p62. This indicates that reassembly of the NPC after mitosis is a stepwise process, and that the Tpr-containing peripheral structures are assembled later than p62.

The TIP1 gene of Saccharomyces cerevisiae encodes an 80 kDa cytoplasmic protein that interacts with the cytoplasmic domain of Sec20p.

The SEC20 gene of Saccharomyces cerevisiae encodes a 50 kDa type II integral membrane glycoprotein that is required for endoplasmic reticulum (ER) to Golgi transport. Here, we have used a genetic screen, based on the lethal effect of overexpressing the cytoplasmic domain of Sec20p, to identify a novel cytosolic factor that interacts with SEC20. This factor is an 80 kDa cytoplasmic protein encoded by the TIP1 (SEC twenty interacting protein) gene. Coimmunoprecipitation and immunofluorescence using Tip1p and Sec20p or its cytoplasmic domain showed that the two proteins physically interact to form a stable complex. Like SEC20, TIP1 is required for ER to Golgi transport and depletion of Tip1p results in accumulation of an extensive network of ER plus small transport vesicles. We therefore propose that Sec20p and Tip1p act together as a functional unit in the ER to Golgi transport step.

The Saccharomyces cerevisiae SEC20 gene encodes a membrane glycoprotein which is sorted by the HDEL retrieval system.

The SEC20 gene product (Sec20p) is required for endoplasmic reticulum (ER) to Golgi transport in the yeast secretory pathway. We have cloned the SEC20 gene by complementation of the temperature sensitive phenotype of a sec20-1 strain. The DNA sequence predicts a 44 kDa protein with a single membrane-spanning region; Sec20p has an apparent molecular weight of 50 kDa and behaves as an integral membrane protein with carbohydrate modifications that appear to be O-linked. A striking feature of this protein is its C-terminal sequence, which consists of the tetrapeptide HDEL. This signal is known to be required for the retrieval of soluble ER proteins from early Golgi compartments, but has not previously been observed on a membrane protein. The HDEL sequence of Sec20p is not essential for viability but helps to maintain intracellular levels of the protein. Depletion of Sec20p from cells results in the accumulation of an extensive network of ER and clusters of small vesicles. We suggest a possible role for the SEC20 product in the targeting of transport vesicles to the Golgi apparatus.

Use of an acrylonitrile-butadiene-styrene (ABS) plastic ring as a matrix in the recovery of bite mark evidence.

Valuable forensic information can be obtained from analysis of human bite mark injuries after careful retrieval of such evidence from living or deceased victims. It is difficult, however, to maintain the anatomical configuration of the skin, especially where body contours complicate the recovery process. Transillumination of the injury pattern in the skin after removal and preservation of the tissue from a deceased victim can provide significant information in the investigation process. A dimensionally stable matrix is required to support the skin's anatomical configuration during and after its removal. The authors have developed a unique and convenient method of heating and contouring a ring of acrylonitrile-butadiene-styrene (ABS) plastic using table salt over a heat source. When this ring is applied to the deceased victim's skin, and a backing material is added for support, removal of the skin and the bite mark can be accomplished more predictably while maintaining the anatomical contour. It is important to record bite marks accurately as soon after discovery as possible; the authors believe that this technique will significantly aid recovery of such evidence either at the crime scene or in the laboratory. A method of inscribing appropriate anatomical markers and case numbers on the rings is also described.

The ERD2 gene determines the specificity of the luminal ER protein retention system.

Luminal ER proteins carry a signal at their C terminus that prevents their secretion; in S. cerevisiae this signal is the tetrapeptide HDEL. Indirect evidence suggests that HDEL is recognized by a receptor that retrieves ER proteins from the secretory pathway and returns them to the ER, and a candidate for this receptor is the product of the ERD2 gene (see accompanying paper). We show here that presumptive ER proteins from the budding yeast K. lactis can terminate either with HDEL or, in the case of BiP, with DDEL. S. cerevisiae does not efficiently recognize DDEL as a retention signal, but exchange of its ERD2 gene for the corresponding gene from K. lactis allows equal recognition of DDEL and HDEL. Thus the specificity of the retention system is determined by the ERD2 gene. We conclude that ERD2 encodes the receptor that sorts luminal ER proteins.