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Comparison of pulmonary autopsy findings of the rats drowned at surface and 50 ft depth.

INTRODUCTION: When a body is recovered from the water after a fatal SCUBA diving accident, it is useful to know if the diver was under pressure or not when he/she took his/her last breath, in order to determine the cause and manner of the death. If the victim was under pressure, the air remained in the lungs of the diver will be equal to the environmental pressure. If the body comes to the surface, the air in the lung will expand according to the Boyle's Gas Law and give mechanical damage to the surrounding tissues, due to decreases in environmental pressure. We designed an experimental study to see the difference in pulmonary autopsy findings of the rats that drowned under normobaric and hyperbaric conditions. METHOD: Forty five male, 250-300 g, Sprague Downey adult rats were divided into three groups. Two groups of rats were drowned under normobaric conditions (Groups DS Group DSS) and the third group at 50 ft pressure (Group DD). The pulmonary autopsy findings of the groups were compared. In the light microscopy, the number of the microscopic fields (x10) containing at least one emphysematous area with longitudinal dimension greater than 300 micro m were compared among the groups. RESULTS: The gross examination revealed a prominent swelling of the lungs in all rats in the Group DD, in comparison to that of the Groups DS and DSS. The number of the microscopic fields, which included at least one emphysematous area with longitudinal dimension greater than 300 micro m out of 150 fields from each of the groups DS, DSS and DD, were 88, 101 and 115 respectively. The difference between the group DS and DD was found to be statistically significant. CONCLUSION: We conclude that in investigating the fatal diving accidents, pulmonary autopsy findings give valuable information whether the death occurred at the surface or at the depth.

Animals↗

Evaluation of the role of abstinence in heroin overdose deaths using segmental hair analysis.

In the body heroin is rapidly metabolized to 6-acetylmorphine and morphine. Victims of lethal heroin overdose often present with fairly low blood concentrations of morphine. Reduced tolerance due to abstinence has been proposed to account for this finding. The aim of the present study was to examine the role of abstinence in drug-related deaths by comparing recent and past exposure to opioids using segmental hair analysis with the postmortem blood morphine concentrations in deceased heroin users. The study included 60 deceased drug addicts in the Stockholm area, Sweden. In 32 cases, death was not related to heroin intake. In 18 of the 28 heroin fatalities, opioids were absent in the most recent hair segment, suggesting a reduced tolerance to opioids. However, the blood morphine levels were similar to those found in the 10 subjects that showed continuous opioid use. Hair and blood analysis disclosed an extensive use of additional drugs that directly or indirectly may influence the opioid system. The results suggest that abstinence is not a critical factor for heroin overdose death. Obviously tolerant subjects die after intake of similar doses. Other factors, particularly polydrug use, seem to be more causally important for these deaths.

Adult↗

Wischnewsky's spots in an ectopic stomach.

Wischnewsky's spots in the mucosa of the stomach have been a well-known sign of death due to hypothermia for many years. Furthermore it is reported that those spots can rarely be found in the esophagus as well. We now report on a case concerning a 93-year-old woman who presented an ectopic stomach with erosions of the mucosa in the intrathoracic part of the stomach that were assessed as Wischnewsky's spots. When she was found dead in her flat, she was completely undressed and showed an injury to the head. The autopsy findings are presented and discussed in view of a possible genesis and pathophysiology of Wischnewsky's spots.

Aged, 80 and over↗

Identify the injury implements by SEM/EDX and ICP-AES.

The forensic investigator is frequently confronted with the discrimination and deduction of injury implements, which is one of the most important physical testimonies in courts. The usual method used in actual cases is from points of morphology. In the forensic discrimination of injury implements, such as metal implements, the analysis and comparison of elements are expected to provide excellent results, and simultaneous multi-elemental analysis is required to analyze various kinds of elements. This study was designed to establish discrimination and deduction of metal injury implements by scanning electron microscope/energy disperse X-ray microanalyzer (SEM/EDX) and inductively coupled plasma atomic emission spectrometry (ICP-AES). Examined metal particles in five wounds made on the skin of domestic pigs, respectively, using Cu-Zn or Cr-Ni coated and carbon steel kitchen implements by EDX. For carbon steel kitchen implements, analyzed five samples from the back and blade separately in the contents and varieties of elements by ICP-AES. In the wounds by the coated implements, the special particles only containing Cu, Zn or Cr, Ni were found. In the wounds by carbon steel kitchen implements, the particles containing Fe, Cr, Si or Fe, Mn, Si were found. The differences of contents of elements between the back and blade was no significant except No. 5 for carbon steel kitchen implements, and the significant differences of elements exited in Cr, Mn, Si, Cu, Mo among the stainless kitchen knives, Mn, Si among the other kitchen implements and for the blade of No. 5 knife, relative standard deviations (R.S.D.s) were significantly different in Mn, Si, Mo, Ti, S, P, Ni. Using EDX to examine the particles in wounds can deduce the categories of metal injury implements, and we can still deduce the different implements in the same category by ICP-AES.

Animals↗

Identification and separation of DNA mixtures using peak area information.

We introduce a new methodology, based upon probabilistic expert systems, for analysing forensic identification problems involving DNA mixture traces using quantitative peak area information. Peak area is modelled with conditional Gaussian distributions. The expert system can be used for ascertaining whether individuals, whose profiles have been measured, have contributed to the mixture. It can also be used to predict DNA profiles of unknown contributors by separating the mixture into its individual components. The potential of our probabilistic methodology is illustrated on case data examples and compared with alternative approaches. The advantages are that identification and separation issues can be handled in a unified way within a single probabilistic model and the uncertainty associated with the analysis is quantified. Further work, required to bring the methodology to a point where it could be applied to the routine analysis of casework, is discussed.

DNA↗

Comparison of two whole genome amplification methods for STR genotyping of LCN and degraded DNA samples.

The analysis of LCN or highly degraded DNA samples presents a challenge for forensic science. Improving the quantity and/or quality of samples would greatly increase the profiling success rate from LCN and degraded samples. Whole genome amplification (WGA) is one method that has such potential. Two commercially available WGA kits, GenomePlex and GenomiPhi, were investigated for use on LCN and degraded DNA samples. Both kits amplified genomic DNA, producing microgram quantities from sub-nanogram templates. Profiling success of LCN DNA samples was increased, with improvements of over 700% from 10pg template DNA compared to non-WGA-amplified control samples. The amplification success with degraded DNA was also improved by WGA. Degraded DNA was simulated using restriction enzymes to demonstrate that the application of WGA can result in the typing of STR loci that could not previously be amplified. An increase in artefacts, such as stutter alleles and amplification biases, were observed in many samples. Results show that WGA is capable of increasing both the quality and quantity of DNA, and has the potential to improve profiling success from difficult samples in forensic casework.

DNA↗

Mitochondrial DNA identification of game and harvested freshwater fish species.

The use of DNA in forensics has grown rapidly for human applications along with the concomitant development of bioinformatics and demographic databases to help fully realize the potential of this molecular information. Similar techniques are also used routinely in many wildlife cases, such as species identification in food products, poaching and the illegal trade of endangered species. The use of molecular techniques in forensic cases related to wildlife and the development of associated databases has, however, mainly focused on large mammals with the exception of a few high-profile species. There is a need to develop similar databases for aquatic species for fisheries enforcement, given the large number of exploited and endangered fish species, the intensity of exploitation, and challenges in identifying species and their derived products. We sequenced a 500bp fragment of the mitochondrial cytochrome b gene from representative individuals from 26 harvested fish taxa from Ontario, Canada, focusing on species that support major commercial and recreational fisheries. Ontario provides a unique model system for the development of a fish species database, as the province contains an evolutionarily diverse array of freshwater fish families representing more than one third of all freshwater fish in Canada. Inter- and intraspecific sequence comparisons using phylogenetic analysis and a BLAST search algorithm provided rigorous statistical metrics for species identification. This methodology and these data will aid in fisheries enforcement, providing a tool to easily and accurately identify fish species in enforcement investigations that would have otherwise been difficult or impossible to pursue.

Animals↗

The detection of sedatives in hair and nail samples using tandem LC-MS-MS.

Drug screening methods were developed to detect alprazolam, clobazam, clonazepam, diazepam, midazolam, oxazepam, temazepam, triazolam, zopiclone, and selected metabolites in human hair and nail samples employing liquid-liquid extraction and tandem liquid chromatography-mass spectrometry (LC-MS-MS). Hair and nail samples were obtained from patients who had recently discontinued or were currently prescribed one or more of the targeted drugs. Prazepam was used as the internal standard for all compounds. Some components in the hair matrix gave the same transitions as some of the analytes but did not compromise the analyses because their retention times differed from those for the target compounds. The analytical run time was 8-10min. Results of the hair analysis of a DFSA victim are also presented.

Adult↗

Postmortem diagnosis of sepsis.

Human sepsis is a spectrum of pathophysiological changes in the host system resulting from a generalized activation and systemic expression of the host's inflammatory pathways in response to infection. Since autopsy findings and routine histology in cases of suspected fatal sepsis are most often unspecific and unconvincing, a number of studies has recently dealt with different methods and markers to better define criteria for the postmortem diagnosis of sepsis. Research carried out on specimens obtained postmortem from sepsis-associated fatalities is an important tool to improve our understanding of inflammatory organ changes and the associated underlying pathophysiological mechanisms. One pitfall the investigator has to be aware of is how to select appropriate case material that constitutes the basis for the setting-up of reference values that derive from such studies. Since no scientific studies have investigated the value of cardiac blood samples in the present context, autopsy blood samples for the determination of biochemical sepsis markers have to derive from the femoral vein. In both sepsis cases as well as controls, the time of death has to be well defined.

Biomarkers↗

Postmortem biochemistry.

Postmortem biochemistry may provide significant information in determining the cause of death. Due to the rapid postmortem breakdown of metabolism and active membrane transport only analytes which are stable in blood can be determined on this fluid compartment, other parameters have to be analysed on other fluid compartments like vitreous humor (VH). However, using another fluid compartment as a mirror of blood at the moment of death involves severe methodical problems. The conceptual problems of reference values in vitreous humor as a mirror of blood are addressed. Additionally, the necessary steps to be taken before calculating the discriminating values between "normal" and "diseased" are described. For all chemical determinations, a clear definition of the site of sample acquisition is necessary. Up to now chemical determinations on alternative fluids have mainly been carried out using instruments calibrated for urine or serum. Developing calibrated methods for analysis of alternative fluids is a further task for the future.

Biomarkers↗

Demands on scientific studies: vitality of wounds and wound age estimation.

Research on vitality and wound age estimation belongs to the classic fields in forensic medicine. Despite large literature data there is still considerable demand of further research and practical transfer of knowledge and techniques to daily casework. Scientific studies must fulfil basic criteria as to appropriate methods, selection of case material, analysis of results and quality control. Nowadays, immunohistochemistry, biochemical tests and molecular biological techniques are mainly used studying questions of vitality and wound age. Investigations can be based on human tissue samples (autopsy material, vital specimens) or animal experiments. The possibilities, advantages and disadvantages of these study designs are described. Indispensable is the use of appropriate control groups or control samples and a sufficient case number which permits statistical analysis. Main strategy is to minimize variations due to methods and investigators as the unavoidable biological variation of vitality processes and wound repair is large enough.

Ethics, Research↗

Post-mortem tissue sampling using computed tomography guidance.

PURPOSE: Currently, in forensic medicine cross-sectional imaging gains recognition and a wide use as a non-invasive examination approach. Today, computed tomography (CT) or magnetic resonance imaging that are available for patients are unable to provide tissue information on the cellular level in a non-invasive manner and also diatom detection, DNA, bacteriological, chemical toxicological and other specific tissue analyses are impossible using radiology. We hypothesised that post-mortem minimally invasive tissue sampling using needle biopsies under CT guidance might significantly enhance the potential of virtual autopsy. The purpose of this study was to test the use of a clinically approved biopsy needle for minimally invasive post-mortem sampling of tissue specimens under CT guidance. MATERIAL AND METHODS: ACN III biopsy core needles 14 gauge x 160 mm with automatic pistol device were used on three bodies dedicated to research from the local anatomical institute. Tissue probes from the brain, heart, lung, liver, spleen, kidney and muscle tissue were obtained under CT fluoroscopy. RESULTS: CT fluoroscopy enabled accurate placement of the needle within the organs and tissues. The needles allowed for sampling of tissue probes with a mean width of 1.7 mm (range 1.2-2 mm) and the maximal length of 20 mm at all locations. The obtained tissue specimens were of sufficient size and adequate quality for histological analysis. CONCLUSION: Our results indicate that, similar to the clinical experience but in many more organs, the tissue specimens obtained using the clinically approved biopsy needle are of a sufficient size and adequate quality for a histological examination. We suggest that post-mortem biopsy using the ACN III needle under CT guidance may become a reliable method for targeted sampling of tissue probes of the body.

Biopsy, Needle↗

Could NF-kappaB and caspase-3 be markers for estimation of post-interval of human traumatic brain injury?

BACKGROUND: Previous studies in a rat model showed expressions of caspase-3 (p20) and NF-kappaB (p65) in different time after TBI. We test the activation changes of caspase-3 and NF-kappaB of human specimen after traumatic brain injury (TBI) in this study to see whether they could be markers to estimate post-intervals of TBI for forensic practice. MATERIAL AND METHODS: Caspase-3 (p20) and NF-kappaB (p65) immunohistochemical staining were performed on 39 TBI specimens (dead from TBI) and eight controls (dead from none TBI reasons) grouped 0, 12, 24, 48, 72, 168, 264 and 480 h. Positive cells were counted and image analysis techniques were used to determine the morphological changes in each group. RESULTS: Immunohistochemical analysis showed a marked induction of caspase-3 (p20) in every injured group compared with normal controls; each positive group has it's morphological character with variant positive cell count. NF-kappaB (p65) did not showed markedly change compared with normal controls until 168 h after TBI and almost all nerve cells were stained by NF-kappaB (p65) in 264 and 480 h groups. CONCLUSION: NF-kappaB (p65) could contribute to estimate delayed death cases after TBI for forensic applications. Caspase-3 (p20) estimating post-TBI intervals are dubious but could suggest TBI exists.

Adult↗

Fibronectin EIIIA splicing variant: a useful contribution to forensic wounding interval estimation.

A fibronectin splicing variant, Fn containing an extra type III domain (EIIIA in rat, ED1 or EDA in human) has recently attracted more attention because of its sensitive response in injury of adult tissue. The characteristic that this form is absent in adult tissue while it is commonly expressed in fetal tissues and injured adult tissue is useful in estimation of injury interval in forensic science. The regulation of fibronectin splicing was studied by immunohistochemistry by using monoclonal antibody to EIIIA on sections from paraffin embedded rat skin sample after contusion. The results indicated that epidermic cells and hair follicle epithelium of rat skin were found positive staining at 6h after injury, and the color became darker with prolonged wounding time. Based on the above result, we invented a type of test paper assayed for EIIIA-Fn splicing variant by using immune colloidal gold technique. After dipping one end of test paper in the supernatant fluid of tissue homogenates of injury skin for few minutes, detecting line could be found. It showed that all experimental injured samples revealed positive staining; the darkness of positive staining was dependent on the injury time, while control normal skin cannot found positive staining. It is concluded that there is a close relationship between the expression of EIIIA-Fn splicing variant and wounding interval, and that the gold-labeled test paper can be useful in distinguishing ante- and post-mortem injury, and in estimation of wounding interval in forensic science.

Alternative Splicing↗

Application of ultrasonography to postmortem examination. Diagnosis of pericardial tamponade.

In postmortem examination, it is difficult to diagnose pericardial tamponade in a dead body from the findings of conventional external examination alone. However, ultrasonography is a common diagnostic tool for pericardial tamponade in clinical practice. We studied the postmortem diagnosis of pericardial tamponade at external examination level by applying an ultrasonographic device. The ultrasonographic findings were compared with the conventional autopsy findings. Among 455 cases of forensic autopsy in Hamburg and Tokyo conducted within 5 days after death, we successfully diagnosed 11 cases of pericardial tamponade by ultrasound imaging prior to autopsy, and failed to diagnose pericardial tamponade in only two cases. In addition, 79 cases of external examination conducted at the Tokyo Medicinal Examiner's Office were also examined with ultrasonography, and we diagnosed three cases of pericardial tamponade and five cases of pericardial effusion. The differences in ultrasonographic findings between tamponade and effusion were relatively clear. Although autopsy provides definitive evidence for the cause of death, sometimes autopsy cannot be performed due to some social factors. In such cases, conventional external examination alone cannot establish a cause of death by pericardial tamponade, and application of diagnostic imaging technique will be helpful. While CT and/or MRI may provide more detailed information than ultrasound imaging, these techniques require special equipment, room and specialist, and most of all involves high cost, which is perhaps the most important consideration in the present atmosphere of medical cost containment. On the other hand, the ultrasonographic devices we use are compact, and can be used directly at the scene of death. Postmortem application of ultrasonography may be a valuable adjunct in the work of medical examiners and forensic pathologists.

Aged↗

Myocardial Cx43 expression in the cases of sudden death due to dilated cardiomyopathy.

PURPOSE: Probing into myocardial connexin (Cx) 43 expression in the cases of sudden death due to dilated cardiomyopathy (DCM) and relationship between Cx43 expression and sudden death. METHOD: Myocardial Cx43 was detected with immunohistochemical staining in the cases of 11 sudden death caused by DCM and 14 cases of control group who died of violent reasons and other diseases, which were autopsied in our department from 1997 to 2003. RESULT: Of 11 cases of DCM, there were 10 men and 1 woman with ranging in age from 7 to 49 years old (x (37.8) years old for 9 adult cases). Of 14 cases in the control group, there were 10 men and 4 women with ranging in age from 11 to 53 years old (x (29.9) years old for 11 adult cases). Myocardial Cx43 expression was obviously decreased in DCM group. Positive dyeing spots were different in size, distribution, color and disparity, some of them were distributed in the form of particle. Obvious change had not been observed in the cases of control group or with only slight changes in coloring degree and expressive area. The quantitative data showed that there was significant difference between two groups (p=0.0075) about Cx43 expressive area, but there was no difference between the left and right ventricles (p>0.05) in each group itself. And there was not difference between the two groups about average optical density of expression. CONCLUSION: Myocardial Cx43 expression is obviously reduced in the patients with DCM who die suddenly. The alteration of quantity and distribution of myocardial Cx43 expression is probably related to sudden death of the patients with DCM.

Adolescent↗

Morphologic, experimental-comparative investigation as an identification of the injuring instrument method.

Aiming to identify the injuring tool characteristics and the tool itself morphologic, experimental-comparative investigations of the skin wound, rib and cartilage injuries taken during the autopsy are performed. During 1995-2004, 489 investigations were performed for this purpose. In 418 cases, knives were submitted for identification of the specific injuring tool (in total-835 knives). In 205 cases the investigation included not only skin wounds, but also the injured rib cartilages. Identification investigations were performed by investigating both the skin wounds morphologic characteristics and dynamic traces-trails in the rib cartilage tissue left by the micro relief of the knife blade edge. In the case of the investigated and experimental skin wounds characteristics coincidence the experimental and comparative dynamic traces investigation was performed when the traces were suitable for the tool identification purposes. In the case of the investigated and experimental skin wounds, dynamic traces coincidence, the totality of the coincided characteristics was considered individual. In those cases, the conclusion included the fact that the injury had been made by a particular knife. According to our data during 1995-2004 in 23 cases-15.9% (5.5% out of the total investigated cases), the knife identification was based on the skin wound characteristics and dynamic traces in the rib cartilage tissue. In our opinion, the dynamic traces in the rib cartilage tissue investigations supplement the identification field and are valuable in the tool identification. In 11 (2.6% out of the total investigated cases) cases knives were identified only by the skin wounds morphologic characteristics, the ribs being not injured or dynamic traces being not suitable for the tool identification.

Cartilage↗

Comparison between lung weight and blood strontium in bodies found in seawater.

This paper examines the use of lung weight increase as an indicator of seawater drowning compared to the amount of Sr absorbed by the blood. The study population was limited to male victims older than 20 years. Significant differences between cases of drowning and "non-drowning" were detected in terms of the lung-heart weight ratio (L/H) (p<0.001) or lung-body weight ratio (L/B) (p=0.005). However, using lung weight (L), L/H or L/B to distinguish between seawater drownings and saltwater non-drownings some overlap was produced. The factor rendering least overlap was L/B, which also appeared to be non-dependent on the victim's age. Our findings suggest that a value of L/B higher than 19.5 g/kg could be a useful indicator of death by drowning, but that when a lower value is found, additional drowning diagnoses would be needed to establish the manner of death.

Adult↗