Reliable, sensitive, rapid and quantitative enzyme-based assay for gamma-hydroxybutyric acid (GHB)

Several assays for gamma-hydroxybutyrate (4-hydroxybutyrate, GHB) have been developed based on the enzyme gamma-hydroxybutyrate dehydrogenase (GHB-DH). Enzymatic oxidation of GHB by NAD+ is coupled to diaphorase-mediated reduction of pro-dye to yield colored product. GHB-DH from Ralstonia eutropha was cloned and expressed as a stable fusion protein easily purified by affinity chromatography. Quantitative initial velocity and endpoint versions of the assay in solution are described. Michaelis-Menten parameters for oxidation of GHB and ethanol were estimated. A semi-quantitative "dipstick" version of the assay on paper also is described. Both solution endpoint and "dipstick" assays are sensitive to about 0.05 mg GHB/mL using 10 microL of sample. Ethanol at concentrations possible in urine and agents used to stabilize physiological fluids for forensics analysis do not interfere significantly. The "dipstick" assay also allows detection of GHB in alcoholic beverages after evaporation of about one-fourth drop of beverage before testing. The enzymatic assay for GHB is reliable, sensitive, inexpensive and rapid.     

Eight short tandem repeats (STR) frequencies for descendants from Terena indigenous Brazilian group

POPULATION: descendants from Terenas an indigenous group.     

A comparison between direct and indirect methods available for human bite mark analysis

Comparison techniques used in bite mark analysis are many and varied, the choice of technique depending largely on personal preference. Until recently, no one technique has been shown to be better than the others, and very little research has been carried out to compare different methods. This study evaluates and compares the accuracy of direct comparisons between suspects' models and bite marks with indirect comparisons in the form of conventional traced overlays of suspects' models or a new method using photocopier-generated overlays. Artificial bite marks in pigskin were made using standardized sets of models and recorded as photographs and fingerprint powder lifts on tape. The bite mark photographs and fingerprint lifts were coded and randomized so that a blind comparison could be made with the models, traced overlays, and photocopier-generated overlays using a modified version of the American Board of Forensic Odontology Scoring (ABFO) System for Bite Marks. It was found that the photocopier-generated overlays were significantly more accurate at matching the correct bite mark to the correct models irrespective of whether the bite mark was recorded photographically or as a fingerprint lift. The photocopier-generated overlays were also found to be more sensitive at matching the correct bite marks to the correct models than the other two methods used. The modified ABFO scoring system was able to discriminate between a correct match and several incorrect matches by awarding a high score to the correct match.     

Relationships between the deinstitutionalization of healthcare for patients with mental disorder, substance abuse, and isolated death

Isolated death (ID) (i.e., dying alone without anyone noticing for several days) has been suggested to be related to social isolation, mental disorder, and alcohol and/or drug abuse. A major transfer of patients with a mental disorder and/or alcohol and/or drug abuse from institutionalized care to treatment as outpatients has been enacted in Sweden during the past decade. On the basis of the assumption that such deinstitutionalization is likely to result in increased social isolation, our working hypothesis was that the incidence of ID among patients belonging to these categories has increased in Sweden. The present study involved all deaths subjected to a medicolegal examination in Stockholm County (with a population of approximately 1.9 million people) during the period 1992-2000. The pattern of ID (defined as cases involving a postmortem delay between death and discovery of at least 1 week), as well as the incidence of fatalities subjected to medicolegal examination with a record of mental disorder and/or alcohol and/or drug abuse was evaluated. Throughout this period, the proportion of the deceased with a record of a mental disorder was high among all the cases examined and higher still among the cases of ID, especially among those younger than 65 years of age. There was a rather limited increase in the incidence of ID and a much more pronounced increase in the number of former psychiatric patients whose deaths were subjected to medicolegal examination, but did not satisfy the criteria for ID. A record of alcohol and/or drug abuse was more common than a diagnosis of mental disorder among both the males and females who died at an age of less than 65, with a clear difference between the cases of ID and non-ID in the case of men. There was no significant increase in incidence over the course of this study. Thus, this study reveals a slight increase in the number of IDs and a more pronounced increase in the number of medicolegal examination of non-IDs of individuals with a record of a mental disorder.     

Spontaneous rupture of the urinary bladder

The report presents the case of a 33-year-old man under the primary assumption of homicide in which the court-ordered autopsy revealed death as a result of bleeding due to a spontaneous rupture of the urinary bladder. The article gives a short summary of the pathomorphological findings and their respective causes, for example the typical location of the rupture at the posterior wall and roof of the bladder and the common concomitant drunkenness. Furthermore, obligatory forensic investigations--beside the autopsy--are mentioned and discussed.     

Comparison of gasolines using gas chromatography-mass spectrometry and target ion response

Gas chromatography-mass spectrometry was used to compare gasoline samples obtained from different sources based on the difference in amounts of certain components found in the headspace of gasoline using target response data. Many suspected arson cases involve comparing an ignitable liquid extracted from fire debris to a liquid found in a suspect's possession to determine if they could have had a common source. Various component ratios are proposed for determining if an unevaporated gasoline sample could have originated from the same source as an evaporated gasoline extracted from fire debris. Fifty and 75% evaporated gasoline samples were both found to contain similar ratios of certain components when compared with its unevaporated source gasoline. The results of the comparisons in this study demonstrate that for cases involving gasoline that has been evaporated up to 50% and extracted from pine, it is possible to eliminate comparison samples as originating from the same source. The results of the 75% comparisons suggest it may be possible to apply the same type of comparison to cases involving 75% evaporated gasoline.     

The rarity of "unusual" [corrected] dispositions of victim bodies: staging and posing

The act of leaving a victim's body in an unusual position is a conscious criminal action by an offender to thwart an investigation, shock the finder and investigators of the crime scene, or give perverted pleasure to the killer. The unusual position concepts of posing and staging a murder victim have been documented thoroughly and have been accepted by the courts as a definable phenomenon. One staging case and one posing case are outlined and reveal characteristics of those homicides. From the Washington State Attorney General's Homicide Investigation and Tracking System's database on murder covering the years 1981-2000 (a total of 5,224 cases), the relative frequency of unusual body dispositions is revealed as a very rare occurrence. Only 1.3% of victims are left in an unusual position, with 0.3% being posed and 0.1% being staged. The characteristics of these types of murders also set them apart: compared to all other murders, in staged murders the victims and killers are, on average, older. All victims and offenders in the staged murders are white, with victims being disproportionately white in murders with any kind of unusual body disposition. Likewise, females stand out as victims when the body is posed, staged, or left in other unusual positions. Whereas posed bodies are more likely to include sexual assault, often in serial murders, there is no evidence of either in the staged cases. Lastly, when a body is left in an unusual position, binding is more likely, as well as the use of more "hands on" means of killing the victim, such as stabbing or cutting weapons, bludgeons, ligatures, or hands and feet.     

Y-chromosome STR system, Y-PLEX 12, for forensic casework: development and validation

The Y-PLEX 12 system, developed for use in human identification, enables simultaneous amplification of eleven polymorphic short tandem repeat (STR) loci, namely DYS392, DYS390, DYS385 a/b, DYS393, DYS389I, DYS391, DYS389II, DYS 19, DYS439 and DYS438, residing on the Y chromosome and Amelogenin. Amelogenin provides results for gender identification and serves as internal control for PCR. The validation studies were performed according to the DNA Advisory Board's (DAB) Quality Assurance Standards. The minimal sensitivity of the Y-PLEX 12 system was 0.1 ng of male DNA. The mean stutter values ranged between 3.76-15.72%. A full male profile was observed in mixture samples containing 0.5 ng of male DNA and up to 400 ng of female DNA. Amelogenin did not adversely affect the amplification of Y-STRs in mixture samples containing male and female DNA. The primers for the Y-STR loci present in Y-PLEX 12 are specific for human DNA and some higher primates. None of the primate samples tested provided a complete profile at all 11 Y-STR loci amplified with the Y-PLEX 12 system. Y-PLEX 12 is a sensitive, valid, reliable, and robust multiplex system for forensic analysis, and it can be used in human forensic and male lineage identification cases.