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1.
Anal Chim Acta ; 1083: 150-156, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31493805

RESUMO

Most of the on-site approaches for inferring of the post-mortem interval are still based on observative data from the direct body inspection, whereas, objective and quantitative analyses, such as potassium in the vitreous humor, are require laboratory instrumentation and skilled personnel. The present paper presents a simple and low cost analytical method suitable for use at the crime scene for inferring the time since death. The method uses a microfluidic paper-based device (µPAD) for the determination of ammonium in the vitreous humor (VH) based on the selective interaction between the ammonium and the Nessler's reagent. The color change was measured in terms of "RGB distance" by using a simple and free smartphone application. The optimized device showed a limit of detection of 0.4 mmol L-1, with between days precision less than 9.3% expressed as relative standard deviation, and accuracy between days from 94.5% to 104.5%. The selectivity of the Nessler's reaction was tested towards the main vitreous humor compounds, and no significant interferences were found. This paper-based analytical device was successfully used for the determination of ammonium ion in VH samples from forensic autopsies. The results obtained with the proposed method, although for a limited number of cases (n = 25), showed a close correlation with the data obtained with an instrumental analysis based on capillary electrophoresis. Moreover, in order to make the evaluation of results as simple as possible, a direct correlation between the color intensity, expressed as RGB distance, and the post-mortem interval was studied and a significant correlation was found (R2 > 0.78). In conclusion, the present preliminary study showes that the proposed device could be an additional tool to the traditional methods for a more accurate, although still presumptive, estimation of the time of death directly at the crime scene.


Assuntos
Compostos de Amônio/análise , Medicina Legal/métodos , Papel , Mudanças Depois da Morte , Corpo Vítreo/química , Adulto , Idoso , Colorimetria/instrumentação , Colorimetria/métodos , Medicina Legal/instrumentação , Humanos , Iodetos/química , Limite de Detecção , Compostos de Mercúrio/química , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Reprodutibilidade dos Testes , Fatores de Tempo , Adulto Jovem
2.
Med Leg J ; 87(1): 32-35, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30070156

RESUMO

In many cases of sexual assault, traces of semen are left behind on the victim's body, clothes and the area in which the assault has taken place. The positive identification of semen is instrumental in supporting such cases. There are several methods of forensic examination of semen reported in literature, but the presence of blood complicates the identification of semen stains. This paper presents one such case study where the presence of blood makes DNA profiling more challenging as the PCR amplification becomes complicated, and the absolute differential isolation is the only way to get the clear profile using identifiler kits.


Assuntos
Impressões Digitais de DNA/métodos , Estupro , Sangue , Criança , Vítimas de Crime , Criminosos , Impressões Digitais de DNA/instrumentação , Feminino , Medicina Legal/instrumentação , Medicina Legal/métodos , Humanos , Masculino , Sêmen/enzimologia , Análise do Sêmen/métodos
3.
Leg Med (Tokyo) ; 34: 58-63, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30193238

RESUMO

Short tandem repeat (STR) analysis is widely used for forensic examinations with a capillary electrophoresis instrument such as the 3500xL Genetic Analyzer. This instrument adapts multi-locus STR kits to examine up to 27 loci using a 6-fluorescent dye system and corrects the spectral overlap between each dye. However, inaccurate spectral correction can cause pull-up peaks. Here, we examined the pull-up peaks observed in GlobalFiler kit data in terms of their peak height ratios and distances from their parent allele peaks when using the 3500xL and the 3130xl Genetic Analyzers. With the 3500xL, 546 pull-up peaks were observed, and their pull-up ratios averaged 1.03 ±â€¯0.32% (range 0.260-2.80%). Of the 546 pull-up peaks, 534 peaks (97.8%) were within ±1 bp from their parent allele peaks. Overall, the pull-up peaks toward adjacent shorter wavelength channels (e.g., from yellow to green) tended to be observed in the left side (shorter bp) of the corresponding parent allele peaks, and the opposite side tendency was observed for those pull-up peaks toward adjacent longer wavelength channels. These tendencies were also observed in the GlobalFiler data generated with the 3130xl and in the data obtained by injecting a J6 matrix standard with LIZ 500 or 600 v2 size standard into the 3500xL and 3130xl. Inspection of raw data revealed that the shift of pull-up peaks from their parent allele peaks was derived from sigmoid, pull-down, or slightly shifted pull-up shapes. Based on the obtained data, we propose a standard for assessment of questionable pull-up peaks.


Assuntos
Impressões Digitais de DNA/instrumentação , Medicina Legal/instrumentação , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Repetições de Microssatélites/genética , Alelos , Eletroforese Capilar/instrumentação , Medicina Legal/métodos , Humanos
4.
Forensic Sci Int ; 291: 44-52, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30138750

RESUMO

Most traditional techniques to recover latent fingermarks from metallic surfaces do not consider the metal surface properties and instead focus on the fingermark chemistry. The scanning Kelvin probe (SKP) technique is a non-contact, non-destructive method, used under ambient conditions, which can be utilised to recover latent prints from metallic surfaces and does not require any enhancement techniques or prevent subsequent forensic analysis. Where a fingermark ridge contacted the metal, the contact potential difference (CPD) contrast between the background surface and the fingermark contact area was 10-50mV. Measurements were performed on the untreated brass, nickel-coated brass and copper metal surfaces and compared to traditional forensic enhancement techniques such as Vacuum Metal Deposition (VMD) using Au-Zn and Au-Ag. Using VMD, the CPD change ranged from 0 to 150mV between the dissimilar metal surfaces affected by the fingermark. In general, SKP worked best without additional enhancement techniques. Scanning Electron Microscope (SEM) scans were used to identify the fingermark contact areas through a sodium, chlorine and oxygen electron probe micro-analyzer (EPMA). The fingermark was observed in the backscattered electron image as the carbon deposits scattered the electrons less than the surrounding metal surface. The fingermark is shown clearly in a Cathodoluminescence scan on the copper sample as it blocks the photon emission at band gap (2.17eV) from the underlying copper oxide (Cu2O) surface. For the first time, SEM, EPMA and Cathodoluminescence techniques were compared to SKP data. Visible and latent fingermarks were tested with latent, eccrinous fingermarks more easily imaged by SKP. Results obtained were very encouraging and suggest that the scanning Kelvin probe technique, which does not need vacuum, could have a place as a first stage analysis tool in serious crime investigation.


Assuntos
Dermatoglifia , Metais Pesados , Microscopia Eletrônica de Varredura , Microscopia/métodos , Medicina Legal/instrumentação , Medicina Legal/métodos , Humanos , Microscopia/instrumentação , Propriedades de Superfície
5.
Fa Yi Xue Za Zhi ; 34(3): 260-263, 2018 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-30051664

RESUMO

OBJECTIVES: To develop a measurement software of lung compression degree to calculate the lung compression ratio in pneumothorax patients accurately and quickly, and then provide an objective assessment of damage degree in forensic clinical identification. METHODS: A volume calculation software was established according to the working principle of the CT instrument. CT data of 15 pneumothorax patients were selected as research objects. The lung compression ratio of pneumothorax patient was calculated by the lung compression volume calculation software of the CT instrument. Meanwhile, the lung compression ratio was also calculated by the developed volume calculation software. The lung compression ratio and operation time calculated by the two methods were analyzed statistically. Scatter plot graphs were draw based on related data, and the developed volume calculation software was verified. RESULTS: The difference between the lung compression ratios calculated by the two methods was not statistically significant, but showed a linear correlation (P<0.05). The operation time of the developed volume calculation software was obviously shorter. CONCLUSIONS: The volume calculation software developed in this study can calculate the lung compression degree of pneumothorax more conveniently and rapidly with easy accessibility, which shows an application value in the forensic practice.


Assuntos
Medicina Legal/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Pulmão/anatomia & histologia , Pneumotórax , Tomografia Computadorizada por Raios X , Humanos , Pulmão/diagnóstico por imagem , Software
6.
Cuad. med. forense ; 24(1/2): 43-49, ene.-jun. 2018. ilus
Artigo em Espanhol | IBECS | ID: ibc-187844

RESUMO

La variabilidad poblacional en Colombia y su marcado mestizaje hace que la morfología del colombiano sea heterogénea, lo que no permite aplicar fielmente los postulados, métodos y técnicas implementadas en el ámbito internacional en poblaciones homogéneas, a la hora de realizar una identificación de individuos esqueletizados. Para llevar a cabo esta identificación, se recurre a modificaciones que amplían el margen de error que cada estándar posee, haciéndolo ineficaz e inexacto para los grupos poblacionales. Motivo por el cual, en este trabajo se desarrolla la problemática de la identificación de individuos esqueletizados en el contexto colombiano, en una etapa histórica de postacuerdo con las Fuerzas Armadas Revolucionarias de Colombia (FARC), y la importancia de las colecciones de referencia osteológica como una herramienta forense e investigativa, donde han de surgir métodos y técnicas propias para la población colombiana, posibilitando las labores de identificación de individuos esqueletizados


The population variability in Colombia and its marked miscegenation makes the morphology of the Colombian is heterogeneous, which does not allow faithfully apply the postulates, methods and techniques implemented internationally in homogeneous populations at the time of making an identification skeletonized individuals. To carry out this identification, we use modifications that increase the margin of error that each standard has, making it ineffective and inaccurate for the population groups. Reason for which, in this work, the problem of the identification of skeletonized individuals in the Colombian context is developed, in a historical stage of post-agreement with the Fuerzas Armandas Revolucionarias de Colombia (FARC) and the importance of the osteological reference collections as a forensic and investigative tool, where methods and techniques must be developed for the Colombian population, making it possible to identify skeletonized individuals


Assuntos
Humanos , Osteologia/instrumentação , Osteologia/métodos , Medicina Legal/instrumentação , Antropologia Forense/instrumentação , Identificação de Vítimas , Colômbia
7.
Forensic Sci Int ; 288: 81-88, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29734053

RESUMO

The Phadebas® Forensic Press Test is routinely used for the detection of saliva. However, assessment of the use of Phadebas® paper for this purpose has not been studied extensively. The suitability of Phadebas® paper as a presumptive screening tool for saliva on forensic exhibits, was investigated by analysing the following: (1) sensitivity, (2) specificity, (3) effects of temperature on sensitivity and specificity, (4) detection of saliva in mixed body fluid samples, and (5) influence of substrate porosity. The results of this study demonstrated that Phadebas® paper is more sensitive to α-amylase activity and less specific for saliva than previously reported. The use of an examination temperature of 37°C had no effect on sensitivity, but increased the incidence of cross-reactivity with other forensically relevant body fluid stains. Blood, urine and vaginal secretions can inhibit the detection of α-amylase activity with Phadebas® paper in mixed stains of saliva and body fluid. Substrate porosity is a weak predictor for the time taken for a saliva stain to achieve a strong positive result on Phadebas® paper. Overall, this study demonstrated that the Phadebas® Forensic Press Test has limitations as a presumptive test for the accurate identification of saliva.


Assuntos
Medicina Legal/instrumentação , Saliva/química , Manejo de Espécimes/instrumentação , Adulto , Análise Química do Sangue , Muco do Colo Uterino/química , Fezes/química , Feminino , Medicina Legal/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/química , Porosidade , Sêmen/química , Sensibilidade e Especificidade , Suor/química , Lágrimas/química , Temperatura , Urina/química , Adulto Jovem , alfa-Amilases/isolamento & purificação
8.
Forensic Sci Int ; 288: 97-106, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29738995

RESUMO

The development of fingerprints in blood on a dark-coloured surface can be difficult. Contrast between the bloodmark and the surface can be difficult to achieve using photography and chemical reagents. The use of haem-reagent ortho-Phenylenediamine (OPD) and Zar-Pro™ strips in the enhancement of bloody impressions were investigated. Depletions of bloodmarks were deposited on black ceramic tiles and aged up to 90 days. OPD, Acid Yellow 7, and Hungarian Red were applied to these tiles and the developed fingermarks were compared using a numerical score system. Zar-Pro™ strips were applied to chemically treated and untreated bloodmarks alike. OPD proved to be effective at developing bloodmarks aged up to 90 days, including latent marks. Despite this capability, OPD did not perform as well as Acid Yellow 7 and so the continued use of Acid Yellow 7 is recommended. Zar-Pro™ strips were able to lift bloodmarks aged up to 90days as well as those chemically treated with either: OPD, Hungarian Red, Acid Yellow 7, or Amido Black although ridge detail was poor. Additional investigation into the capabilities of Zar-Pro™ strips for this purpose is recommended.


Assuntos
Manchas de Sangue , Dermatoglifia , Fenilenodiaminas , Manejo de Espécimes/instrumentação , Corantes , Medicina Legal/instrumentação , Medicina Legal/métodos , Humanos , Propriedades de Superfície , Fatores de Tempo
9.
Crit Rev Microbiol ; 44(4): 504-521, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29513060

RESUMO

Emerging infectious diseases remain among the leading causes of global mortality. Traditional laboratory diagnostic approaches designed to detect and track infectious disease agents provide a framework for surveillance of bio threats. However, surveillance and outbreak investigations using such time-consuming approaches for early detection of pathogens remain the major pitfall. Hence, reasonable real-time surveillance systems to anticipate threats to public health and environment are critical for identifying specific aetiologies and preventing the global spread of infectious disease. The current review discusses the growing need for monitoring and surveillance of pathogens with the same zeal and approach as adopted by microbial forensics laboratories, and further strengthening it by integrating with the innovative nanotechnology for rapid detection of microbial pathogens. Such innovative diagnostics platforms will help to track pathogens from high risk areas and environment by pre-emptive approach that will minimize damages. The various scenarios with the examples are discussed where the high risk associated human pathogens in particular were successfully detected using various nanotechnology approaches with potential future prospects in the field of microbial forensics.


Assuntos
Doenças Transmissíveis Emergentes/diagnóstico , Medicina Legal/métodos , Nanotecnologia/métodos , Animais , Doenças Transmissíveis Emergentes/epidemiologia , Surtos de Doenças , Medicina Legal/instrumentação , Medicina Legal/tendências , Humanos , Nanotecnologia/instrumentação , Nanotecnologia/tendências
10.
Forensic Sci Int ; 285: 50-57, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29433011

RESUMO

Cadaver body bags are the conventional method to contain a human body or human remains, which includes the use for storage and transportation of the deceased at any crime scene or disaster scene. During disasters, most often than not, the first responders including the police will be equipped with cadaver body bags to do scene processing of human remains and collection of personal belongings at the disaster site. However, in an unanticipated large scale disasters involving hundreds and thousands of fatalities, cadaver body bags supplies may be scarce. The authors have therefore innovated the cling film plastic wrap as an alternative for the cadaver body bag used at the disaster site. The plastic wrap was tested on six different experimental subjects, i.e. both adult and child mannequins; body parts of the mannequin figure (arm and hand); a human adult subject and an unknown dead body. The strengths of the cling film plastic wrap are discussed in comparison with the cadaver body bag in the aspects of costing, weight, duration of the wrap, water and body fluid resistant properties, visibility and other advantages. An average savings of more than 5000% are noted for both adult body wrap and child body wrap compared to the cadaver body wrap. This simply means that the authors can either wrap 25 adult dead bodies or 80 children dead bodies with the cost of 1 cadaver body bag. The cling film plastic wrap has proven to have significant innovation impact for dead body management particularly by the first responders in large scale disasters. With proper handling of dead bodies, first responders can manage the dead with dignity and respect in an overwhelmed situation to facilitate the humanitarian victim identification process later.


Assuntos
Bandagens , Restos Mortais , Cadáver , Desastres , Medicina Legal/instrumentação , Plásticos , Serviços Médicos de Emergência , Medicina Legal/métodos , Humanos
11.
Talanta ; 175: 443-450, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28842014

RESUMO

A label-free biosensor based on white light reflectance spectroscopy for the determination of PSA as semen indicator in forensic samples is presented. The sensor is based on a two-step immunoassay which employs the same polyclonal anti-PSA antibody as capture and detection antibody followed by reaction with streptavidin as a signal enhancement step. The whole assay time was set to 10min; 5min reaction of immobilized antibody with the PSA calibrators or the samples, 3min reaction with the biotinylated anti-PSA antibody and 2min reaction with streptavidin. Following this protocol, a detection limit of 0.5ng/mL was achieved and the assay's linear response range extended up to 500ng/mL. Thus, taking into account the quantification limit of 1.0ng/mL and the average PSA concentration in semen (0.2-5.5mg/mL), semen quantities of a few nanoliters could be detected. The accuracy of the sensor developed was demonstrated through recovery (% recovery ranged from 89.6 to 106) and semen dilution experiments. A linear correlation was found for semen dilutions ranging from 5000 to 360,000. The lack of interference by other bodily fluids was confirmed by analysing stains of blood, urine and saliva prior to and after the addition of semen. Finally, the sensor was evaluated by analysing 51 forensic casework samples which were also analysed with a semi-quantitative membrane strip test (Seratec® PSA), through microscopic detection of spermatozoa, and male DNA identification through detection of Y chromosome. The results obtained with the sensor were in excellent agreement with those provided by an immunoradiometric assay kit (PSA-RIACT) and in complete agreement with the findings using the membrane strip assay, spermatozoa and Y chromosome detection. The excellent analytical performance and small size of the instrument make the sensor developed an attractive tool for use in forensic evidence screening for semen detection.


Assuntos
Técnicas Biossensoriais/métodos , Antígeno Prostático Específico/análise , Sêmen/química , Anticorpos Imobilizados/química , Técnicas Biossensoriais/instrumentação , Desenho de Equipamento , Feminino , Medicina Legal/instrumentação , Medicina Legal/métodos , Humanos , Imunoensaio/instrumentação , Imunoensaio/métodos , Limite de Detecção , Masculino , Estupro/diagnóstico , Análise Espectral/instrumentação , Análise Espectral/métodos
12.
Wounds ; 29(8): 222-228, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28570249

RESUMO

OBJECTIVE: This study aimed to determine if an alternate light source (ALS) can be used to detect tissue trauma before visible manifestations of tissue injury are evident with the naked eye. MATERIALS AND METHODS: Ten participants were recruited and gave consent, and 7 completed the study. Researchers examined and photographed participants' heels in ambient light to establish baseline. A series of photographs using ALS and camera were taken as follows: violet wavelength at 415 nm to 445 nm with yellow lens; blue wavelength at 455 nm to 515 nm with orange lens; and green wavelength at 535 nm to 575 nm with red lens. Participants were examined weekly for 6 consecutive weeks to ascertain skin changes in ambient light and through the ALS. RESULTS: Overt tissue changes were noted when viewed with the ALS and camera compared with visual screens in ambient light. Descriptive statistics were calculated for all wavelengths. Two chi-square tests of independence were run to look for relationships between wavelength and the number of detected injuries (absorption). CONCLUSIONS: Participants presenting with nonblanching erythema in ambient light showed significant tissue absorption under ALS and camera, depicting the actual scope and magnitude of the tissue trauma. Participants with scars, areas of previous injury, and pigmentary changes also showed significant absorption at those sites. These combined findings indicate that ALS can detect tissue trauma and areas at risk not readily visible by the naked eye. This noninvasive tool could help identify patients in the early stages of tissue trauma as well as screen for sites of previous injury that are at risk for subsequent breakdown, saving significant health care dollars and improving outcomes and quality of life.


Assuntos
Eritema/patologia , Medicina Legal/instrumentação , Lesão por Pressão/patologia , Pigmentação da Pele/fisiologia , Diagnóstico Precoce , Fluorescência , Humanos , Raios Infravermelhos , Valor Preditivo dos Testes , Estudos Prospectivos , Qualidade de Vida , Sensibilidade e Especificidade , Raios Ultravioleta
13.
Anal Bioanal Chem ; 409(25): 5821-5836, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28634759

RESUMO

The proliferation of new psychoactive substances (NPS) in recent years has resulted in the development of numerous analytical methods for the detection and identification of known and unknown NPS derivatives. High-resolution mass spectrometry (HRMS) has been identified as the method of choice for broad screening of NPS in a wide range of analytical contexts because of its ability to measure accurate masses using data-independent acquisition (DIA) techniques. Additionally, it has shown promise for non-targeted screening strategies that have been developed in order to detect and identify novel analogues without the need for certified reference materials (CRMs) or comprehensive mass spectral libraries. This paper reviews the applications of HRMS for the analysis of NPS in forensic drug chemistry and analytical toxicology. It provides an overview of the sample preparation procedures in addition to data acquisition, instrumental analysis, and data processing techniques. Furthermore, it gives an overview of the current state of non-targeted screening strategies with discussion on future directions and perspectives of this technique. Graphical Abstract Missing the bullseye - a graphical respresentation of non-targeted screening. Image courtesy of Christian Alonzo.


Assuntos
Drogas Desenhadas/análise , Espectrometria de Massas/métodos , Psicotrópicos/análise , Detecção do Abuso de Substâncias/métodos , Animais , Fracionamento Químico/métodos , Drogas Desenhadas/farmacocinética , Medicina Legal/instrumentação , Medicina Legal/métodos , Humanos , Espectrometria de Massas/instrumentação , Psicotrópicos/sangue , Psicotrópicos/urina , Manejo de Espécimes/métodos , Detecção do Abuso de Substâncias/instrumentação
14.
Vet Radiol Ultrasound ; 58(3): 245-258, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28233422

RESUMO

Imaging studies are often of evidentiary value in medicolegal investigations involving animals and the role of the veterinary radiologist is to interpret those images for courts as an expert or opinion witness. With progressing interest in prosecuting animal crimes and strengthening of penalties for crimes against animals, the participation of veterinary radiologists in medicolegal investigations is expected to increase. Veterinary radiologists who are aware of radiographic and imaging signs that result in animal suffering, abuse, or neglect; knowledgeable in ways radiology and imaging may support cause of death determinations; conversant in postmortem imaging; comfortable discussing mechanisms and timing of blunt or sharp force and projectile trauma in imaging; and prepared to identify mimics of abuse can assist court participants in understanding imaging evidence. The goal of this commentary review is to familiarize veterinary radiologists with the forensic radiology and imaging literature and with the advantages and disadvantages of various imaging modalities utilized in forensic investigations. Another goal is to provide background information for future research studies in veterinary forensic radiology and imaging.


Assuntos
Diagnóstico por Imagem/veterinária , Medicina Legal/instrumentação , Radiologistas , Radiologia/instrumentação , Medicina Veterinária/instrumentação , Animais , Diagnóstico por Imagem/instrumentação , Radiologistas/normas
16.
Adv Exp Med Biol ; 906: 407-418, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27620313

RESUMO

Pulmonary ThromboEmolism (PTE) is an important disease for legal medicine. Because of their sudden lethal onset, generally medicolegal autopsies show few clinical information when PTE is the cause of death. During medicolegal autopsies, the autopsy operator must answer to important questions. For example, autopsy operator can need to assess the casual relationship between PTE and recent accident, such as trauma or long air travel. Furthermore, the autopsy operator needs to investigate the pathology of PTE as a cause of sudden cardiovascular death. It is relatively simple to confirm a fatal massive thromboembolus in the initial stage of thoracic investigations, but sometimes it might be difficult to distinguish this from postmortem clot. In such cases histopathological examination can help in the differentiation. Histological examination is also required for observation of chronological changes of the thrombi. Chronological evaluation is an important factor especially to determine whether the death coincides with the date of a specific accident/event or instead there is an earlier onset of PTE. In addition, histological sections sometimes show additional information, such as tumor fragments in cases of malignancy or small fragments of bone marrow in cases of active resuscitation, that can be useful in a medicolegal scenario. Furthermore, new diagnostic tools are arising, which they can be very helpful in the individuation of this frequently underdiagnosed disease. The goal of our work is to investigate these aspects through the review of the recent literature.


Assuntos
Autopsia/métodos , Morte Súbita Cardíaca/patologia , Patologia Legal/métodos , Embolia Pulmonar/diagnóstico , Autopsia/instrumentação , Causas de Morte , Angiografia por Tomografia Computadorizada , Médicos Legistas/ética , Médicos Legistas/legislação & jurisprudência , Medicina Legal/instrumentação , Medicina Legal/métodos , Patologia Legal/instrumentação , Humanos , Imuno-Histoquímica , Pulmão/irrigação sanguínea , Pulmão/patologia , Embolia Pulmonar/mortalidade , Embolia Pulmonar/patologia , Fatores de Tempo
17.
Anal Bioanal Chem ; 408(29): 8467-8481, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27744478

RESUMO

The prevalence of new psychoactive substances (NPSs) in forensic casework has increased prominently in recent years. This has given rise to significant legal and analytical challenges in the identification of these substances. The requirement for validated, robust and rapid testing methodologies for these compounds is obvious. This study details the analysis of 13 synthesised diphenidine derivatives encountered in casework using presumptive testing, thin layer chromatography and gas chromatography-mass spectrometry (GC-MS). Specifically, the validated GC-MS method provides, for the first time, both a general screening method and quantification of the active components for seized solid samples, both in their pure form and in the presence of common adulterants. Graphical Abstract Chemical synthesis and forensic analysis of 13 diphenidine-derived new psychoactive substance(s).


Assuntos
Medicina Legal/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Piperidinas/análise , Psicotrópicos/análise , Calibragem , Cromatografia em Camada Delgada , Medicina Legal/instrumentação , Limite de Detecção , Piperidinas/química , Psicotrópicos/química , Reprodutibilidade dos Testes
18.
Biosensors (Basel) ; 6(3)2016 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-27527231

RESUMO

Microfluidic devices may offer various advantages for forensic DNA analysis, such as reduced risk of contamination, shorter analysis time and direct application at the crime scene. Microfluidic chip technology has already proven to be functional and effective within medical applications, such as for point-of-care use. In the forensic field, one may expect microfluidic technology to become particularly relevant for the analysis of biological traces containing human DNA. This would require a number of consecutive steps, including sample work up, DNA amplification and detection, as well as secure storage of the sample. This article provides an extensive overview of microfluidic devices for cell lysis, DNA extraction and purification, DNA amplification and detection and analysis techniques for DNA. Topics to be discussed are polymerase chain reaction (PCR) on-chip, digital PCR (dPCR), isothermal amplification on-chip, chip materials, integrated devices and commercially available techniques. A critical overview of the opportunities and challenges of the use of chips is discussed, and developments made in forensic DNA analysis over the past 10-20 years with microfluidic systems are described. Areas in which further research is needed are indicated in a future outlook.


Assuntos
DNA , Medicina Legal/instrumentação , Medicina Legal/métodos , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas , Microfluídica/instrumentação , DNA/química , DNA/isolamento & purificação , Humanos , Técnicas de Amplificação de Ácido Nucleico/métodos
19.
J Forensic Sci ; 61(2): 501-508, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27404625

RESUMO

A mechanical device that uses gravitational and spring compression forces to create spatter patterns of known impact velocities is presented and discussed. The custom-made device uses either two or four springs (k1 = 267.8 N/m, k2 = 535.5 N/m) in parallel to create seventeen reproducible impact velocities between 2.1 and 4.0 m/s. The impactor is held at several known spring extensions using an electromagnet. Trigger inputs to the high-speed video camera allow the user to control the magnet's release while capturing video footage simultaneously. A polycarbonate base is used to allow for simultaneous monitoring of the side and bottom views of the impact event. Twenty-four patterns were created across the impact velocity range and analyzed using HemoSpat. Area of origin estimations fell within an acceptable range (ΔXav = -5.5 ± 1.9 cm, ΔYav = -2.6 ± 2.8 cm, ΔZav = +5.5 ± 3.8 cm), supporting distribution analysis for the use in research or bloodstain pattern training. This work provides a framework for those interested in developing a robust impact device.


Assuntos
Manchas de Sangue , Medicina Legal/instrumentação , Desenho de Equipamento , Humanos , Software , Gravação em Vídeo
20.
J Anal Toxicol ; 40(5): 338-44, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27107099

RESUMO

Reporting a measurement of uncertainty helps to determine the limitations of the method of analysis and aids in laboratory accreditation. This laboratory has conducted a study to estimate a reasonable uncertainty for the mass concentration of vaporous ethanol, in g/210 L, by the Intoxilyzer(®) 8000 breath analyzer. The uncertainty sources used were: gas chromatograph (GC) calibration adjustment, GC analytical, certified reference material, Intoxilyzer(®) 8000 calibration adjustment and Intoxilyzer(®) 8000 analytical. Standard uncertainties attributed to these sources were calculated and separated into proportional and constant standard uncertainties. Both the combined proportional and the constant standard uncertainties were further combined to an expanded uncertainty as both a percentage and an unit. To prevent any under reporting of the expanded uncertainty, 0.10 g/210 L was chosen as the defining point for expressing the expanded uncertainty. For the Intoxilyzer(®) 8000, all vaporous ethanol results at or above 0.10 g/210 L, the expanded uncertainty will be reported as ±3.6% at a confidence level of 95% (k = 2); for vaporous ethanol results below 0.10 g/210 L, the expanded uncertainty will be reported as ±0.0036 g/210 L at a confidence level of 95% (k = 2).


Assuntos
Intoxicação Alcoólica/diagnóstico , Testes Respiratórios/instrumentação , Etanol/análise , Calibragem , Cromatografia Gasosa/métodos , Medicina Legal/instrumentação , Humanos , Incerteza
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