0000000000019663
AUTHOR
Fernando Verdú
A new chemical aid for criminal investigation: dyes and latent prints
Criminalistics is a field in which there are many opportunities for the practical application of chemical reagents and the use of analytical methods that provide answers to enigmas at crime scenes. Common reagents in biochemical and medical test methods can be useful for criminalistics (forensic science). Dyes are one type of reagent that can be used in obtaining crime scene evidence. This work describes a new application of CI Solvent Black 3 dye in the location of latent fingerprints. The results show that CI Solvent Black 3 can be successfully applied in the location and development of recent and non-recent latent fingerprints on porous surfaces.
DNA Evidence Uncompromised by Active Oxygen
Currently, forensic sciences can make use of the potential of instrumental analysis techniques to obtain information from the smallest, even invisible, samples. However, as laboratory techniques improve, so too should the procedures applied in the search for and initial testing of clues in order to be equally effective. This requires continuous revision so that those procedures may resolve the problems that samples present. As far as bloodstains are concerned, there are methods available that are recognized as being both highly sensitive and effective. Nevertheless, the marketing of new cleaning products, those that contain active oxygen, has raised doubts about the ability of those procedu…
Chemistry in Crime Investigation: Sodium Percarbonate Effects on Bloodstains Detection
Chemistry plays a leading role in crime investigation. In the study of bloodstains, chemical reactions provide the means for the detection. All these procedures have been thoroughly studied. However, recently, a new source of error has been found: washing stains with "active oxygen" detergents abrogates presumptive and human hemoglobin tests for bloodstains (although visible). The aim of this investigation was to evaluate the ability of pure sodium percarbonate-main component of detergents-to abrogate presumptive and human hemoglobin tests. Then, a solution to this problem could be found. The results demonstrate that pure sodium percarbonate-itself-is able to abrogate all tests, as well as …
The 1258 GA polymorphism in the neuropeptide Y gene is associated with greater alcohol consumption in a Mediterranean population.
Abstract Neuropeptide Y (NPY) is a neurotransmitter widely distributed in the central nervous system. Several studies have demonstrated that increases of NPY are associated with reduced alcohol intake and anxiety manifestations. The Leu7Pro polymorphism in the NPY has been associated with alcohol consumption, but evidence is scarce. In the Spanish Mediterranean population, this variant is not polymorphic. Thus, our aim is to identify novel functional variants in the NPY and to investigate the impact of these markers and others previously described on alcohol consumption in this population. A total of 911 subjects (321 men and 590 women) from the Spanish Mediterranean population were recruit…
Amelogenin test: From forensics to quality control in clinical and biochemical genomics.
Abstract Background The increasing number of samples from the biomedical genetic studies and the number of centers participating in the same involves increasing risk of mistakes in the different sample handling stages. We have evaluated the usefulness of the amelogenin test for quality control in sample identification. Methods Amelogenin test (frequently used in forensics) was undertaken on 1224 individuals participating in a biomedical study. Concordance between referred sex in the database and amelogenin test was estimated. Additional sex-error genetic detecting systems were developed. Results The overall concordance rate was 99.84% (1222/1224). Two samples showed a female amelogenin test…
Accuracy, Reliability, and Safety of Luminol in Bloodstain Investigation
ABSTRACTThe reliability of luminol as a presumptive test reagent was studied in this work. The possibility of obtaining a false negative subsequent to contamination of the test specimen was determined. The behavior of luminol with respect to a contaminant was compared to other reagents used in similar tests. Following an analysis of the test results, other test sensitivity, and safety data, it was concluded that luminol is a more reliable reagent than others due to a higher improbability of producing false positives and false negatives, apart from being safer than other substances. It should, therefore, be considered as a “preferable” or “first choice” reagent for use in presumptive tests.
The working day in medicine: lessons from the air.
This article discusses whether it would be wrong to explain a mistake involving medical responsibility on the basis of an opinion that the professional was not in the optimum physical or mental state at the moment the mistake took place.
Solving underwater crimes: development of latent prints made on submerged objects.
Underwater crime scenes always present a challenge for forensic researchers, as the destructive effect of water considerably complicates the chances of recovering material of evidential value. The aim of this study is to tackle the problem of developing marks that have been left on submerged objects. Fingermark deposition was randomly made on two surfaces - glass and plastic whilst the material was submerged under tap water and then left for one to fifteen days before drying and development. For their later development, various reagents - Black Powder, Silver Metallic Powder, Fluorescent Powder, Sudan Black (powder and solution) and Small Particle Reagent - were used and the effectiveness o…
Association between Opioid Receptor mu 1 (OPRM1) Gene Polymorphisms and Tobacco and Alcohol Consumption in a Spanish Population.
Evidence gained from animals and humans suggests that the encephalic opioid system might be involved in the development of drug addiction through its role in reward. Our aim is to assess the influence of genetic variations in the opioid receptor mu 1 on alcohol and tobacco consumption in a Spanish population. 763 unrelated individuals (465 women, 298 men) aged 18-85 years were recruited between October 2011 and April 2012. Participants were requested to answer a 35-item questionnaire on tobacco and alcohol consumption, as well as to complete the AUDIT and Fagerström tests. Individuals were genotyped for three polymorphisms in the opioid receptor mu 1 (OPRM1) gene, using a TaqMan® protocol. …
Luminous lip-prints as criminal evidence.
Luminescence is specially a useful property for the search of invisible evidences at the scene of a crime. In the latent fingerprints particular case, there are at one's disposal fluorescent reagents for their localization. The study of latent lip prints (that is lip prints from protective lipstick, or permanent or long-lasting lipstick that do not leave any visible marks) is more recent than fingerprints study. Because of the different composition of both types of prints, different reagents have been tried out on their developing. Although, lysochromes are particularly useful reagents to obtain latent lip prints, it may occur on coloured or multicoloured surfaces, the developing is not per…
El diagnóstico genético del sexo mediante el test de la amelogenina: Métodos y posibles fuentes de error
El diagnóstico del sexo a partir de indicios biológicos es crucial en la ciencia forense en general y en la investigación criminal, en particular. La amelogenina -proteina codificada en los cromosomas sexuales- se viene utilizando con ese fin desde la última década del siglo pasado. Existen divergencias en secuencia y tamaño entre los alelos codificados en el cromosoma X y el cromosoma Y (AMELX y AMELY, respectivamente). Esta es la base que ha permitido su amplia utilización en ciencias forenses para el diagnóstico genético del sexo. No obstante, recientemente se han publicado casos en los cuales el resultado del test de la amelogenina no corresponde con el sexo legal (oficial) del individu…
Predisposición genética en el consumo de alcohol: el caso de la Alcohol Deshidrogenasa 1C
Introduccion: El consumo de alcohol se presenta frecuentemente asociado a determinados delitos, siendo en unas ocasiones atenuante o eximente, y en otras una infraccion penal per se. Se han identificado numerosos factores geneticos y ambientales que predisponen al consumo de alcohol. Nuestro objetivo ha sido estudiar la prevalencia del polimorfismo Ile349Val en la alcohol deshidrogenasa 1C que da lugar a la isoforma gamma 2 (metabolizador lento), y estudiar su asociacion con el consumo de alcohol asi como reflexionar sobre la dimension de la implicacion de estas variantes geneticas en la Medicina Legal. Material y Metodos: Se ha genotipado el polimorfismo Ile 349Val en 869 individuos proced…
Just lip prints? No: there could be something else
Bleach interference in forensic luminol tests on porous surfaces: more about the drying time effect.
As criminals try to avoid leaving clues at the scene of a crime, bloodstains are often washed away, but fortunately for investigators, they are difficult to eliminate completely. Porous surfaces easily retain blood traces, which are sometimes invisible to the naked eye. The reagent of choice for detecting latent blood traces on all types of surfaces is luminol, but its main disadvantage is a high degree of sensitivity to oxidising contaminants in the blood sample. If household bleach is used to clean bloodstains, presumptive tests are invalidated. Hypochlorites, however, are known to be unstable and deteriorate over time, and this feature could be of help in preventing household bleach-indu…
A Role for Judges in Assisted Dying
Medically provoked death, whether euthanasia or assisted suicide, is a common issue for discussion in various forums, participants coming from widely differing fields of knowledge, among who are, of course, doctors. Substantial legal differences exist in Europe on this issue and in an ever-wider Europe, it is essential, for practical reasons, that legislation be standardised. We would like to propose possible regulations that would provide effective safeguards in the application of euthanasia or assisted suicide.
Use of fluorescent dyes for developing latent lip prints
Advances in the sensitivity of techniques used to examine latent prints (finger or labial) make it necessary to find more effective methods of locating prints on different surfaces. The most difficult surfaces are those which are porous or multicoloured, in which case the developed print may not be easily seen. This study analyses the effectiveness of two fluorescent dyes, Nile Blue and Nile Red, in developing both recent and older latent lip prints on porous and multicoloured surfaces. The results indicate that Nile Red is a very effective reagent for the development of latent lip prints on difficult surfaces of this type.
More about the developing of invisible lipstick-contaminated lipmarks on human skin: The usefulness of fluorescent dyes
At the present time fingerprints are one of the simplest, and most reliable means of identification. Increasingly, crime scene investigators look for palm, foot, ear or lip prints. With regard to lip prints, the use, very common today, of protective or permanent lipsticks allow the production an invisible lipmark (or invisible lipstick-contaminated lipmark) which is possible to develop. Some results have already been published about developers useful for different kinds of surfaces (both porous and non-porous) as well as those which are more efficient in case of old or recent prints. The latest studies are about the developing on human skin, and they prove the usefulness of lysochromes (spe…