A biomechanical study of the human vertebral artery with implications for fatal arterial injury

We studied the biomechanical behaviour of ring and strip specimens from along the length of 18 vertebral arteries taken from 16 subjects aged 28-90 years, in order to consider some of the factors which may play a role in vertebral artery rupture. The method was chosen to allow a comparison between circumferential distension (ring samples) and longitudinal extension, (strip samples). The samples were extended between the jaws of a tensile testing apparatus until the specimen broke and a number of biomechanical parameters were derived. These were the percentage extension to break, the tensile strength, Young's modulus and the peak load. There were a number of important findings. The vertebral artery was shown to be susceptible to longitudinal stretching with a number of strip samples breaking when extended by as little as 16-20%. The tensile strength and load at peak of the strip specimens were correspondingly lower than for the ring samples. Marked intersubject variations were shown for all these parameters and prominent changes in behaviour occurred along the vertebral artery. This study indicates that the artery may be susceptible to head and neck movements which cause the vessel to stretch, and intersubject variations in behaviour may be one important explanation for the marked differences in outcome which appear to exist in subjects who suffer broadly similar head and neck insults.     

Unusual infant death: dog attack or postmortem mutilation after child abuse?

An unusual form of fatal child abuse is reported in which investigations by the police and the medical examiner were able to distinguish blunt force head trauma followed by postmortem dismemberment from a fatal dog attack. A discussion of the approaches used to ascertain the correct diagnosis is presented, as well as an overview of dog attacks on humans.     

An analysis of the usefulness of specific stages in the pathologic investigation of sudden infant death

Retrospective analysis of autopsy findings in 60 infants who had been found unexpectedly dead in their cribs or beds in South Australia from 1994 to 1998 was undertaken to determine the diagnostic usefulness of individual stages in the postmortem investigation. Positive findings occurred in 2 of 43 scene examinations (3%), 2 of 60 external examinations (3%), 2 of 11 radiologic examinations (18%), 8 of 60 internal examinations (13%), 7 of 60 histologic examinations (12%), and 3 of 58 microbiologic examinations (5%). No positive findings were detected on toxicologic screening. Not every case underwent each diagnostic step. This gave alternative diagnoses to sudden infant death syndrome (SIDS) in 15 cases (25%). This study demonstrates an increase in the percentage of cases of unexpected infant death due to causes other than SIDS; it also shows the diagnostic yield of individual stages in the postmortem evaluation of such cases. Negative findings were important in giving validity to the diagnosis in the 45 cases that were ultimately designated as SIDS.     

The transfer of petrol on to clothing and shoes while pouring petrol around a room

This study was aimed at measuring the approximate amount of petrol transferred on to the clothing and shoes of a person during the action of pouring petrol around a room. Two different heights of pouring and two different types of floor surface (carpet and concrete) were investigated. Results show that for all the combinations examined petrol was always transferred to the shoes and often transferred to the upper and lower clothing. This information illustrates the necessity of analysing the clothing and particularly the shoes of any suspected arsonists for the presence of hydrocarbon fuels.     

Portuguese population and paternity investigation studies with a multiplex PCR--the AmpFlSTR Profiler Plus

A Portuguese Caucasian population of 146 unrelated individuals was studied. DNA samples were amplified by multiplex PCR for D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317 and D7S820 using the AmpFlSTR Profiler Plus PCR Amplification Kit (Perkin-Elmer). All loci met Hardy-Weinberg expectations. Forensic statistical parameters were according to those obtained by other authors. Statistical differences were observed concerning three loci when comparing the Portuguese Caucasian population and an Italian Caucasian population, although these differences mainly concern the less frequent alleles. Eighty-three paternity investigation cases were analysed. Exclusions in between three and nine loci were observed in all the 23 exclusion cases obtained. Most of the non-exclusion cases had probability of paternity > 99.9%. Two cases with an isolated genetic incompatibility between the alleged father and the child were detected, which may indicate probable mutation cases. These results demonstrate that the AmpFlSTR Profiler Plus is a suitable multiplex for paternity investigation in the Portuguese population.     

Mass screening in low-income populations: the challenges of securing diagnostic and treatment services in a national cancer screening program

Funding for many mass screening programs for low-income and uninsured populations provides resources for screening tests, yet only rarely does it provide coverage for necessary follow-up diagnostic and treatment services. The National Breast and Cervical Cancer Early Detection Program (NBCCEDP), a federally funded initiative that provides cancer screening to low-income uninsured and underinsured women, covers some diagnostic follow-up tests and no treatment services. We conducted in-depth case studies of seven state programs participating in the NBCCEDP to investigate the strategies and approaches being used to secure diagnostic and treatment services. The results suggest that the program relies on a patchwork of resources--at state and local levels--to provide diagnostic and treatment services. This includes a number of components of local safety nets, all of which are unstable and have uncertain futures. Public health disease-screening initiatives need to reconsider the feasibility of continued reliance on case-by-case appeals to the local safety net for diagnostic follow-up and treatment services.     

Screening and determination of benzodiazepines in whole blood using solid-phase extraction and gas chromatography/mass spectrometry

Benzodiazepines are one of the most widely prescribed drugs for the treatment of a wide spectrum of clinical disorders. They are used as anticonvulsants, anxiolytics, hypnotics or muscle relaxants with different duration of action. In this paper, a simple and sensitive method for the determination of benzodiazepines in whole blood using solid-phase extraction and gas chromatography/mass spectrometry (GC/MS) is described. The drugs spiked in whole blood were extracted with an Oasis HLB solid-phase extraction cartridge (Waters), which contains a copolymer designed to have a hydrophilic-lipophilic balance. GC/MS analysis was performed using a Shimadzu QP-5000 equipped with a BPX5 capillary column (15 mx0.32 mm I.D., film thickness 0.25 microm, SGE). Nineteen benzodiazepines and two thienodiazepines were well separated from each other on their SIM chromatograms and also on the TIC with the exception of oxazolam to cloxazolam separation. The blank extract from whole blood gave no peaks that interfered with all benzodiazepines and thienodiazepines on the chromatogram. The calibration curves for selected benzodiazepines with fludiazepam as an internal standard showed excellent linearity over the concentration range 5-500 ng/ml blood with a correlation coefficients of >0.995. The detection limits ranged from 0.2 to 20 ng/ml blood. The method is simple and sensitive for the determination of benzodiazepines in whole blood and seems to be useful in the practice of forensic science.     

Simultaneous determination of THC-COOH and THC-COOH-glucuronide in urine samples by LC/MS/MS

A fast method using liquid-liquid extraction and HPLC/tandem-mass spectrometry (LC/MS/MS) was developed for the simultaneous detection of 11-Nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid beta-glucuronide (THC-COOH-glucuronide) and 11-Nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in urine samples. This highly specific method, which combines chromatographic separation and MS/MS analysis, can be used for the confirmation of positive immunoassay results even without hydrolysis of the sample or derivatisation of extracts. Liquid-liquid extraction was optimised: with ethylacetate/diethylether (1:1, v/v) THC-COOH-glucuronide and THC-COOH could be extracted in one step. Molecular ions of the glucuronide (MH(+), m/z 521) and THC-COOH (MH(+), m/z 345) were generated using a PE/SCIEX turboionspray source in positive ionisation mode; specific fragmentation was performed in the collision cell of an API 365 triple-quadrupole mass spectrometer and yielded major fragments at m/z 345 (for THC-COOH-glucuronide) and m/z 327 as well as m/z 299 for both cannabinoids. Chromatographic separation was performed using a reversed-phase C8 column and gradient elution with 0.1% formic acid/1 mM ammonium formate and acetonitrile/0.1% formic acid. Retention times were 22.2 min for the glucuronide and 26.8 min for THC-COOH. After enzymatic hydrolysis of urine samples with beta-glucuronidase/arylsulfatase (37 degrees C, 5 h), THC-COOH-glucuronide was no longer detectable by LC/MS/MS in urine samples. However, the THC-COOH concentration was increased. For quantitation of THC-COOH, THC-COOH-D(3) was added to the urine samples as internal standard prior to analysis. From the difference of THC-COOH in the native urine and urine after enzymatic hydrolysis, molar concentration ratios of THC-COOH-glucuronide/THC-COOH in urine samples of cannabis users were determined and found to be between 1.3 and 4.5.