Trials and tribulations of using beta-amyloid precursor protein immunohistochemistry to evaluate traumatic brain injury in adults

Axonal pathology is increasingly identified by beta-amyloid precursor protein (betaAPP) immunohistochemistry in the brains of patients who may or may not have a history of trauma. The presence of betaAPP-IR(+) has been variously interpreted as either that diffuse traumatic axonal injury (TAI) is indeed a universal finding in cases of fatal traumatic brain injury (TBI) or there are other causes of betaAPP-IR(+) axons which under certain circumstances may be sufficient to mimic TBI and therefore make the medico-legal interpretation of certain cases very difficult. To address some of the uncertainties we have undertaken a detailed analysis of the amount and distribution of betaAPP immunohistochemistry in 63 cases of fatal TBI, 17 cases of patients dying after cardiac arrest, 12 cases dying in association with status epilepticus, 3 cases of carbon monoxide (CO) poisoning, 13 cases of hypoglycaemia and in 60 controls. Three patterns of betaAPP-IR(+) were identified. First, diffuse multi-focal, second, corresponding to the outline of an infarct or haematoma, and thirdly a mixture of the two. The first pattern was seen in cases of the lesser grades of TAI, CO poisoning, and hypoglycaemia, the second pattern in cases in which there was evidence of raised intracranial pressure and the third in cases of severe TAI. It is concluded that the proper interpretation of cases requires the examination of a sufficient number of blocks ( [Formula: see text] ), processing using standardised protocols including betaAPP immunohistochemistry and in some cases the mapping of any IR(+) on anatomical line diagrams. betaAPP carried out on a small number of randomly taken blocks is likely to lead to misinterpretation of the clinico-pathological correlations and possibly to a miscarriage of justice.     

Accidental insulin overdose

Exogenous insulin has been used for many years to treat diabetes mellitus. Due to the complex nature of insulin therapy, there have been numerous accidental overdoses by these patients. Unfortunately, in other instances, insulin has been used as an agent for suicide and homicide in diabetics as well as nondiabetics. Presented here is a fatal case of accidental insulin overdose in a nondiabetic. Following the case presentation, we review insulin pharmacology and the methods of diagnosing insulin overdose postmortem. In any case of insulin overdose, a comprehensive scene investigation to document the amount and type of insulin used, along with information revealing the source of the insulin is critical. In addition, a complete autopsy, including appropriate laboratory studies, is needed to make a diagnosis in these cases. Proper attention should be given to collection and storage of blood samples, as these specimens often yield the strongest evidence of insulin overdose.     

Utility of the Y-STR typing systems Y-PLEX 6 and Y-PLEX 5 in forensic casework and 11 Y-STR haplotype database for three major population groups in the United States

The Y-PLEX 6 and Y-PLEX 5 systems enable analysis for 11 Y-STR loci. We present here the utility of these systems in forensic casework. A total of 188 samples, including 127 evidence samples, were analyzed using either or both of the systems. The evidence sample types included fingernail scrapings, sperm or seminal fluid, epithelial cells, blood and other tissues. The Y-STR typing systems provided useful probative results in difficult cases. A reference database for Caucasian (n = 517), African American (n = 535), and Hispanic (n = 245) population groups within the United States was generated for estimating the haplotype frequency in forensic casework. Among the individuals profiled, 311 Caucasians, 412 African Americans, and 194 Hispanics provided unique profiles in their respective population datasets. This is the first report describing the haplotype database for the set of 11 Y-STR loci recommended by the Scientific Working Group on DNA Analysis Methods (SWGDAM). Linkage analysis reveals that the frequencies from forensically important autosomal loci can be multiplied with the Y-STR haplotype frequency. The results from Y-PLEX systems have been accepted in courts in the United States.     

The application of an automated allele concordance analysis system (CompareCalls) to ensure the accuracy of single-source STR DNA profiles

A powerful method for validating a scientific result is to confirm specific results utilizing independent methodologies and processing pathways. Thus, we have designed, developed and validated an automated allele concordance analysis system (CompareCalls, patent pending) that performs comparisons between two independent DNA analysis platforms to ensure the highest accuracy for allele calls. Application of this system in a quality assurance role has shown the potential to eliminate greater than 90% of the STR analysis required of a DNA data analyst. While this system is broadly applicable for use with any two independent STR analysis programs, either prior to or following human data review, we are presenting its application to data generated with the ABI Prism Genotyper software system versus data generated with the SurelockID system. With the automated allele concordance analysis system, the GeneScan DNA fragment data generated from an ABI 377 gel image are analyzed in two independent pathways. In one analysis pathway, the GeneScan data are imported into Genotyper software where STR labels are assigned to the fragment data based upon the criteria of the Kazam 20% macro. The "Kazam" macro provided with the Genotyper program works by labeling all peaks in a category (or locus) and then filtering (or removing) the labels from peaks, such as those in stutter positions, that meet predefined criteria. In the second pathway, the GeneScan data are imported into the SurelockID analysis platform where STR labels and error messages are assigned to the fragment data based upon hard-coded allele calling criteria and quality parameters. The resulting STR allele calls for each analysis platform are then compared, utilizing the automated allele concordance analysis system. Any differences in the STR allele calls between the two systems are flagged in a discordance report for further review by a qualified DNA data analyst. The automated allele concordance analysis system guides the DNA data analyst to the discordant data generated by either analysis platform. Additionally, the analyst is also directed to data that are of less than pristine quality which may have an increased potential for errors in interpretation by either analysis platform or by a human DNA data analyst. Implementation of an automated allele concordance analysis system will yield high-quality data for CODIS and free the human DNA data analyst to perform other critical duties within the laboratory.     

Neurovisualization methods in diagnostics of consequences in light craniocerebral trauma

The purpose of the case study was to elucidate the frequency rate of pathological changes as registered by computer tomography (CT) and magnetic-resonance tomography (MRT) of the head in patients with chronic cerebral blood-circulation deficiency (CBD), functional disorders and vegetative nervous pathologies in presence (in their medical histories) of closed-type cranial trauma concomitant with concussion of the brain (CB) or without such trauma. A comparative analysis revealed a minor prevalence in the number of pathological changes in patients with CBD concomitant with CB. As for other nosological forms, the quantities of changes, expressed in percent, were virtually identical. A conclusion was made on the need to examine the patients of the discussed category by neurovisualization in the acute and remote periods of trauma.     

The role of retroperitoneal hematomas in thanatogenesis of pelvic trauma

A brief statistical analysis of the pelvic hematomas' evolution in traumas with various localizations is presented in the article. The current published data were made use of to describe the state-of-art for the time being. Finally, problems related with the forensic-medical aspects of the issue are defined, and methods to cope with them are appropriately suggested.     

The identification of antigens of systems AB0, GM,and haptoglobin (HP) phenotypes in mixed bloodstains of human and domestic goose

The traditional methods of investigations according to systems AB0, Gm and Hp were used to define the serological specificity of home gooses' blood. The experimental examinations' results related with mixed bloodstains of man and home gooses are described. A possibility is demonstrated to identify the blood group factors of man in bloodstains with admixture of home-goose blood.