P. Hooft

Reckless behaviour related to the use of 3,4-methylenedioxymethamphetamine (ecstasy): apropos of a fatal accident during car-surfing

SummaryA 26-year-old man died from severe brain contusion after falling from a moving car during an attempt at car-surfing. Toxicological urine screening was positive for amphetamines, the blood analysis revealed a MDMA level of 0.63 mg/l and a blood alcohol concentration of 1.23 g/l. The case is another example of the bizarre and reckless behaviour which may result from the euphorogenic activity of ecstasy and the circumstances in which it is commonly used.ZusammenfassungEs wird vom Todesfall eines 26-jährigen Mannes berichtet, der sich beim Versuch des „Auto-Surfen” auf einen fahrenden Wagen tödliche Schädelhirnverletzungen zuzog. Das toxikologische Urin-Screening erbrachte das Vorhandensein von Amphetaminen, und die Analyse des Blutes führte zum Nachweis von 0,63 mg/L MDMA und einer Blutalkoholkonzentration von 1,23 g/L. Der vorliegende Fall ist ein weiteres Beispiel für die bizarre und leichtsinnige Verhaltensweise unter Einfluß von MDMA („Ecstasy”), welche auf die euphorisierende Wirkkomponente und die Umstände, unter denen es eingenommen wird, zurückzuführen ist.

Interference of body products, food and products from daily life with the modified zinc test and the acid phosphatase test

The modified qualitative zinc test and the qualitative acid phosphatase test were applied to a total of 1774 semen-free stains made from human body products (n = 575), food products (n = 801), beverages (n = 146), water (n = 120) and other products from daily life (n = 132), in order to assess the degree of interference of these products with the preliminary screening for semen. The zinc test gave positive results in, respectively, 2.4, 3.1, 1.4, 14.1 and 23.5% of the samples, whereas the acid phosphatase test was positive in 3, 3.3, 0, 1.7 and 0% of the samples. Given the large number of positive test results found for products which eventually may be present in stains from alleged sexual assaults, it is concluded that positive screening test results should be interpreted with great caution.

The zinc test as an alternative for acid phosphatase spot tests in the primary identification of seminal traces

The value of the acid phosphatase spot test in the primary visualization and identification of seminal traces is hampered by the sensitiveness of the enzyme to biodegradation. An alternative spot test is proposed, based on the high concentration of the more stable zinc metal in seminal plasma. The proposed zinc spot test is simple and suitable for on site investigation. Although the sensitivity in fresh stains is lower than that of the acid phosphatase spot test, this is largely compensated by the lower sensitiveness to biodegradation. The specificity for semen is higher than that of the acid phosphatase spot test. In vaginal swabs it was nevertheless seen, that samples should be taken within 24 h after alleged sexual assault to give reliable results.

EVALUATION OF THE MODIFIED ZINC TEST AND THE ACID PHOSPHATASE TEST AS PRELIMINARY SCREENING METHODS IN SEXUAL ASSAULT CASE MATERIAL

The modified zinc test and a commercially available acid phosphatase test were compared as to their screening parameters according to the microscopical finding of spermatozoa in cases of alleged sexual assault. The study involved 65 pieces of evidence material. It was found that the modified zinc test has a higher sensitivity and higher predictive values than the acid phosphatase test. However, when both tests are combined in parallel, the sensitivity and the negative predictive value could be raised to 99%. This finding suggests that a negative result obtained from the parallel combination of the modified zinc test and the acid phosphatase test predicts very well that no spermatozoa will be found at microscopical examination. Since the latter technique is the only one to give absolute proof of the seminal origin of stains or traces, the parallel combination of the zinc test and the acid phosphatase test might be useful in sorting out these cases or materials that deserve further investigation by more elaborate techniques.

On the influence of data source in aggregated data studies: a comparative study of suicide information based on death certificates and judicial files.

STUDY OBJECTIVE--The aim was to assess the differences in suicide data obtained from different database sources. DESIGN--Death certificate based data on suicidal deaths were compared with the information obtained from the non-natural death investigation files at the Public Prosecutors Office. SETTING--The study was confined to the time period of 1981-1984 and to the residents of the district of Leuven (Belgium) who died in the district. MAIN RESULTS--Differences were found in the number of suicidal deaths reported as well as in the demographic variables, the distribution of suicide methods, and the place of death. Sixty percent of the records in both databases could be matched for all variables studied (age, gender, civil state, place of death, and suicide method), and another 10% if only place of death was allowed to differ. For 4.5% of the cases in the judicial files and for 8% of the records in the official statistics database no corresponding record from the other data source could be found. Based on simple probability statistics [P(missing record)+P(different information[present)] the possible minimum global information bias could be estimated to range from 7 to 42%. CONCLUSIONS--Different epidemiological pictures of suicide mortality may result from studying different data sources.

A more sensitive modification of the zinc test for seminal traces suitable for stable test paper strips

A more sensitive modification of the zinc test for semen has been developed, which can be used either as a solution or incorporated into test papers. The latter retain their sensitivity for at least 3 months.

Comparative study of the sensitivity and specificity of the zinc and acid phosphatase spot tests for the detection of seminal stains

SummaryThe sensitivity and specificity of a zinc spot test for the detection of semen were compared with those of an acid phosphatase detection method. As screening techniques both tests were found to be very sensitive, but the zinc test was more specific and was more reliable in older and especially in deteriorated specimens. It is concluded that the zinc spot test deserves at least the same place as the acid phosphatase test in the primary investigation of suspected semen stains and might well be the test of choice in older and poorly preserved stains.ZusammenfassungSensitivität und Spezifität eines Fleckentests zum Spermanachweis auf der Basis der Zinkkonzentration im Samen wurden mit den genannten Gütekriterien der sauren Phosphatasetechnik verglichen. Beide Tests waren als Suchtests geeignet, aber der Zinktest erwies sich als spezifischer und zuverlässiger für ältere und denaturierte Proben. Demnach kommt dem Zinktest als Sperma-Suchtest zumindest derselbe Stellenwert zu, wie der Phosphatase-Methode. Bei alten und schlecht erhaltenen Spuren sollte dem Zinktest der Vorzug gegeben werden.

In vitro changes in human spermatozoa exposed to gastric juice: Laboratory findings as a support for forensic practice

SummarySamples of complete human semen were incubated in gastric juice for different time periods at 37°C, and by simulating the post-mortem temperature decrease of the human body. The changes in the spermatozoa were similar in both experiments. Short incubation specimens were examined directly with interference contrast microscopy and showed an almost immediate immobilization of spermatozoa when they were brought in contact with gastric juice. Specimens with longer incubation periods were stained with alcalic fuchsine and examined by immersion microscopy. There was a morphologically stable plateau for the heads of the spermatozoa for up to 6h of incubation. The tails disappeared progressively in the first 45 min. After more than 6h of incubation a progressive swelling and lysis of the heads was observed. Spermatozoa could be recognized for up to 7 days of incubation.ZusammenfassungMenschliche Spermaproben wurden bei 37°C für unterschiedliche Zeitspannen mit Magensaft versetzt und die Änderungen von Motilität und Morphologie der Spermien untersucht. In einer zweiten Versuchsanordnung wurde zusätzlich die postmortale Temperatursenkung simuliert. In beiden Versuchsanordnungen waren die Spermienbefunde identisch. Die Spermien wurden nahezu unmittelbar nach Kontakt mit dem Magensaft immobilisiert. Bei den längeren Inkubationszeiten verschwanden alle Spermienschwänze in den ersten 45 min, die Morphologie der Spermienköpfe änderte sich nicht während der ersten 6h, danach kam es schnell zu einer Lysis. Dennoch konnten bis zum 7. Inkubationstag morphologisch normale Spermien beobachtet werden.

Bloodgroup simulating activity in aerobic gram-negative oral bacteria cultured from fresh corpses

The gram-negative aerobic oral bacterial flora of 100 consecutive corpses was isolated. After the identification and culturing of the isolated organisms, blood grouping was performed by the haemagglutination inhibition technique on dried culture smears, the dried culture medium and a dried ethanol extract of the bacteria. Forty-seven of the samples showed a gram-negative aerobic bacterial growth, giving 58 microorganisms of 14 different species. Positive blood grouping results were found in two of them (Escherichia coli and Serratia marcescens), both of type B. It is concluded that occasional mistyping of blood groups on saliva and oral material may be caused by the oral gram-negative aerobic flora, especially if the specimens are contaminated or putrefying.

ABO bloodgrouping on tooth material

The ABO bloodgroup was determined on the pulp, dentin and enamel of 35 teeth using the adsorption-elution technique. A bloodstained compress from the extraction wound was used as the reference sample. Twenty teeth were examined within 6 weeks after extraction and fifteen teeth were examined 6-10 months after extraction. It was found, that bloodgrouping on pulp gives fairly good results, whereas the possibilities for correct bloodgrouping seem to be limited for dentin and debatable for enamel. Similar results were found in both groups of teeth.