Journal of Forensic Reserarch (JFR) | |
| Welcome, anonymous (Log in) | ![]() |
|
Exposure Standards for Digital and Analogue Dry Skull Orthopantomography Posted by editor.jfr Tuesday, 2011-December-27 Forensic or scientific practices may require producing orthopantomography of dry skulls, that lack soft tissue, therefore modifications on the usual technique should be necessary. With the objective of standardizing the postmortem digital and analogue panoramic radiography this research produced a single a digital radiography and 13 analogue panoramic images, using different exposure configurations and four different objects to try to overcome the effects of the lack of soft tissue radiation absorption on the analog radiographs. A gel based ice pack, a 20 mm dental wax block, and a 0.5 mm metallic foil were placed in different points of the device. Also a previously exposed and developed film was placed inside the cassette between the unexposed film and the intensifying screen. The images were presented to 15 dentists of several specialties, who graded and ranked the images. In conclusion, the digital panoramic was easily obtained at a 60 kV and 2 mA settings and on analog equipments the use of two films inside the cassette achieved best results with 63 kV and 06 mA exposure settings. Times of Detection of Drugs of Abuse in Saliva: Study of Arrested Population Posted by editor.jfr Tuesday, 2011-December-27 Aim: Detection of drugs of abuse is interesting in legal procedures. The aims of the study were: 1: Evaluating the detection time of drugs of abuse in saliva in an arrested population, drugs consumers that are taken into judicial custody in a maximum time of 72 hours from their detention. 2- Verifying analytical results with self reported reference of the subjects.
Participants: 50 oral fluid samples coming from arrested people that are taken into judicial custody in police officer’s courts of the city of Barcelona. The study was carried out in the Laboratory of the Institute of Legal Medicine of Catalonia. The design study was a cross sectional study. Drug tested were: cocaine, amphetamines and related compounds, cannabis and opiates. The time of previous consumption was of 1-3 days.
Measurements: The oral fluid samples were analysed by gas- chromatography-mass spectrometry.
Findings: Positive results were obtained in 40% of the samples. Cocaine was detected in the 73.9% of positive results to this drug. Cannabis was detected in the 28.5%, Opiates was detected in the 23, 1%. Amphetamines were not detected.
Conclusions: It is important to stand out the high rate of cocaine positive results in relation with the time passed and abstinence consumption of 1-3 days. Oral fluid may be a good sample for cocaine detection in drug consumers. Accidental fatal intoxication with Carbon Monoxide Posted by editor.jfr Tuesday, 2011-December-27 Despite repeated warnings, newspaper reports of fatalities and public health and safety campaigns; accidental deaths from carbon monoxide poisoning continue to occur. They can be from accident, ignorance, criminal negligence or foolhardiness; what ever the reason such deaths are tragic and often avoidable. The case presented here was some of these. The physiology and biochemistry is discussed as well as other unusual causes of death by suffocation. This includes the use and abuse of helium from party balloons and nitrous oxide from the misuse of whipped cream dispensers provoking near suffocation and the occasional deaths, though fortunately rare Prediction Model Validation: Normal Human Pigmentation Variation Posted by editor.jfr Tuesday, 2011-December-27 In a past study, we developed multiple linear regression (MLR) models that employed three single nucleotide
polymorphisms (SNPs) that predicted a significant proportion of variation in pigmentation phenotypes from a large
population cohort (n=789, training sample). Multiple linear regression models were developed for skin reflectance,
eye color, and two aspects of hair color (log of the ratio of eumelanin-to-pheomelanin and total melanin). In this report,
using an independent cohort (n=242 , test sample), we 1) externally cross-validated the prediction models, and
2) tested and refined the algorithm presented in the study by Valenzuela and colleagues, (2010). Relative shrinkage
was moderate for skin reflectance (23.4%), eye color (19.4%), and the log of the ratio of eumelanin-to-pheomelanin
in hair (37.3%), and largest for total melanin (67%) in hair. Independent construction of predictive models using our
algorithm for the test sample set yielded the same or similar models as the training sample set. Two of the three
SNPs composing the models were the same, with some variability in the third SNP of the model. The Michael Jackson Autopsy: Insights Provided by a Forensic Anesthesiologist Posted by editor.jfr Tuesday, 2011-December-27 Based on toxicology findings performed on samples taken at the time of autopsy, the cause of Michael Jackson’s
death was determined to be acute propofol intoxication with a contributory benzodiazepine effect. The manner of
death was determined by the coroner to be homicide. At the center of this case are several anesthetic medications.
Insight into the toxicology, review the autopsy results, and summary of the findings are provided from a forensic
anesthesiologist’s point of view. STR Profiling of Human Cell Lines: Challenges and Possible Solutions to the Growing Problem Posted by editor.jfr Tuesday, 2011-December-27 Genomic DNA preparations from 60 human cell lines from the National Cancer Institute (NCI), 48 human cell
lines from American Type Culture Collection (ATCC) and 19 embryonic cell lines were profiled for autosomal short
tandem repeat (STR) loci using the AmpFℓSTR® Identifiler® kit. Each DNA sample was profiled at least twice to ensure
consistency and reproducibility of results. The resulting STR profiles were compared with the STR profiles in the
database of ATCC. The allele calls for the common loci between the Identifiler® kit and the database were identical
except for one DNA sample, which we attribute to amplification artifacts. We have observed a high percentage of
the STR loci exhibiting allelic imbalance. Certain STR loci for some cell lines exhibited 3 or more alleles. This type
of observation can result from a unique profile for a given cell line or as the result of clonotypic heterozygosity and is
not necessarily due to contamination. Our study demonstrates that STR based technologies are useful for cell line
authentication applications. These data, combined with data from other researchers, will enable the development of
a standard genotyping protocol for cell line authentication. Molecular Forensic Approaches to the Taxonomic Assessment of Bacteria in a Commercial Consortia Posted by editor.jfr Tuesday, 2011-December-27 The characterization of low complexity (only a few species present) bacterial communities or commercial consortia
products in terms of microbial composition can require a variety of molecular techniques for supporting forensic
investigations. We examined a low complexity commercial consortium productfor water treatment application as a
model for a tiered molecular approach to studying microbial communities. PCR amplification of 16S rDNA and cpn60
genes were performed on total genomic DNA extracted from the consortium. First, the PCR amplicons were cloned,
sequenced and subjected to both DGGE and RFLP analysis, or they were fluorescently labeled and hybridized to
a dual backbone taxonomic DNA microarray. Secondly, total genomic DNA from the commercial consortium was
subjected to quantitative PCR to determine the concentration of the different components.
The data showed that the dual backbone DNA microarray is extremely useful as a first step to identify the major
members of the consortium, including lot-to-lot variation of the commercial product, as validated by independent
analyses. More importantly, the DNA microarray proved to be a useful screening tool to detect unexpected and
potentially pathogenic microbes in the commercial product. This tiered approach using a DNA microarray screen can
be a useful guide for application of more rapid and targeted molecular tools in forensic investigations of microbial
communities. «Previous page | Next page »
|
Archive |
| Copyright © 2011 - All Rights Reserved , Powered by Omics Publishing Group | |