Evaluation of Postmortem Cerebrospinal Fluid S100B Protein and Serotonin Levels: Comparison of Suicidal Versus Nonsuicidal Deaths in Konya,Turkey

Although suicide is a preventable public health problem, objective assays for suicide risk are limited. In this study, it was aimed to determine levels of S100B protein and serotonin as a marker for risk of suicide. S100B protein and serotonin levels were investigated with ELISA method in the cerebrospinal fluid (CSF) in medicolegal autopsy cases, including those of suicide cases (n = 32) and nonsuicide cases (n = 56). The CSF S100B levels were higher (9.3 ± 2.9 ng/mL vs. 5.4 ± 2.0 ng/mL), and serotonin levels were lower (10.4 ± 4.9 ng/mL vs. 19.0 ± 5.7 ng/mL) in suicide group than nonsuicide group (p < 0.05). There was no correlation between S100B protein and serotonin levels with gender, age groups, postmortem interval, and cause of death. It is concluded that both S100B protein and serotonin in CSF may be useful for determination of suicide risk.     

Use of Cardiac Injury Markers in the Postmortem Diagnosis of Sudden Cardiac Death

In the daily practice of forensic pathology, sudden cardiac death (SCD) is a diagnostic challenge. Our aim was to determine the usefulness of blood biomarkers [creatine kinase CK‐MB, myoglobin, troponins I and T (cTn‐I and T), and lactate dehydrogenase] measured by immunoassay technique, in the postmortem diagnosis of SCD. Two groups were compared, 20 corpses with SCD and 8 controls. Statistical significance was determined by variance analysis procedures, with a post hoc Tukey multiple range test for comparison of means (p < 0.05). SCD cases showed significantly higher levels (p < 0.05) of cTn‐T and cTn‐I compared to the control group. Although only cases within the first 8 h of postmortem interval were included, and the control group consisted mainly of violent death cases, our results suggest that blood troponin levels may be useful to support a diagnosis of SCD.     

Measurement of Postmortem Pupil Size: A New Method with Excellent Reliability and Its Application to Pupil Changes in the Early Postmortem Period

Measurement of postmortem pupil width is a potential component of death time estimation. However, no standardized measurement method has been described. We analyzed a total of 71 digital images for pupil–iris ratio using the software ImageJ. Images were analyzed three times by four different examiners. In addition, serial images from 10 cases were taken between 2 and 50 h postmortem to detect spontaneous pupil changes. Intra‐ and inter‐rater reliability of the method was excellent (ICC > 0.95). The method is observer independent and yields consistent results, and images can be digitally stored and re‐evaluated. The method seems highly eligible for forensic and scientific purposes. While statistical analysis of spontaneous pupil changes revealed a significant polynomial of quartic degree for postmortem time (p = 0.001), an obvious pattern was not detected. These results do not indicate suitability of spontaneous pupil changes for forensic death time estimation, as formerly suggested.     

The Estimation of Postmortem Serum Urea via the Ultrafiltration of Hemolyzed Blood

Postmortem serum urea has been demonstrated as an objective indicator for the forensic diagnosis of cause of death. However, samples used in postmortem biochemical analysis are always affected by hemolysis. To investigate whether hemolysis affects the biochemical analysis of urea and to explore the feasibility of using ultrafiltration to process hemolyzed blood samples, three different levels of hemolyzed blood samples were used to assess the influence of hemolysis on postmortem biochemical analysis of urea, and two ultrafiltration methods were used to process the hemolyzed blood samples. Bias% was used to assess the interference of hemolysis. Our results showed that heavy hemolysis had a significant influence on the biochemical analysis of urea. Both ultrafiltration methods in the present study could significantly reduce the interference of hemolysis, with the |bias%| of methods A and B decreasing from 69.74% ± 99.14% to 12.18% ± 7.23% and 10.77% ± 8.09%, respectively, compared to the original serum. After regression correction, there was no significant difference between the urea concentration in the ultrafiltrates of the two ultrafiltration methods and that in the original serum, which suggested that the postmortem serum urea concentration could be estimated by the corrected urea concentration in the ultrafiltrate. The current study also provided possible pretreatment methods for postmortem biochemical analysis of other biomarkers in hemolyzed blood samples of forensic practice.     

阿维菌素在急性中毒死家兔体内的再分布研究

目的考察阿维菌素在急性中毒死家兔体内的再分布。方法按最小致死量一次性灌胃250mg/kg阿维菌素,HPLC法检测家兔死后0h、24h、48h和72h中阿维菌素的含量。结果给家兔一次性灌胃250mg/kg阿维菌素的临床死亡时间为120.6±9.2min(±s,n=10);测定了阿维菌素的致死血浓度和致死组织浓度;家兔死后0h~72h心血和各主要脏器组织中阿维菌素含量存在体内再分布现象;确定肝、肾、肺为最佳组织检材。结论阿维菌素在急性中毒死家兔体内的再分布数据,对法医办理此类案件具有重要参考价值。     

Entomological and Cardiologic Evidence of Time Since Death in Short Postmortem Intervals

Estimating the time since death of the deceased is a main goal in forensic investigations, but this can be challenging due to contradictory results derived from different investigations at the scene of death. We present a case of a 78‐year‐old woman, found dead in a small forest with broad‐leaved trees, whose husband had a history of domestic violence. Routinely performed investigations, such as postmortem rectal temperature and lividity, yielded inconsistent time since death results between only a few and longer than 20 h. This difficulty was most likely caused by high ambient temperatures of up to 38.0°C, which negatively influenced the informative value of the applied nomogram method. Additionally, performed entomological investigation of fly maggots (Lucilia illustris) recovered from the corpse and the assessment of heart pacemaker data revealed consistent and incontrovertible results. The presented case highlights the benefits of information provided by entomological investigations and data evaluation of cardiac implantable electronic devices and the combined use of the two techniques.     

Brain Fluid Content Related to Body Position and Postmortem Interval – An Animal Model

Adult male Sprague Dawley rats were euthanized and placed in a horizontal or vertical (head‐down) position at room temperature, after which brain fluid content was measured by a moisture analysis technique at variable time points. No significant difference in brain fluid content was observed between horizontal and vertical postmortem positions. A significant increase in brain fluid content was demonstrated 3, 6, and 24 h after death, with maximal fluid content observed at 24 h. Specifically, the brain fluid content of control animals was 77.79 ± 0.36%, increasing to 80.05 ± 0.22% at 24 h (p < 0.0001). This study has demonstrated no significant differences in brain fluid content related to postmortem position, suggesting that a head‐down position is not associated with increased brain fluid content or swelling. However, significant temporal increases in brain fluid content after death, most likely related to cerebral liquefaction, occur.     

A Forensic Entomological Analysis Can Yield an Estimate of Postmortem Interval,and Not Just a Minimum Postmortem Interval: An Explanation and Illustration Using a Case

Several authors claimed that a forensic entomological analysis can never be interpreted as the postmortem interval (PMI), but that it can be interpreted as a minimum postmortem interval (PMI_min), or dead for not less than X amount of time. Because in most instances, a PMI estimate should be a range, that is, the set of values from maximum postmortem interval (PMI_max) to PMI_min, objections to PMI estimation are objections to PMI_max estimation. The arguments for this position did not address the substantial body of literature describing estimation of both PMI_max and PMI_min using insect succession analysis. This report reviews the scientific issues and presents a recent homicide investigation in which several forensic entomology experts used the absence of carrion insects on the corpse, a kind of succession analysis, to estimate PMI or PMI_max.     

An Aquatic Decomposition Scoring Method to Potentially Predict the Postmortem Submersion Interval of Bodies Recovered from the North Sea

This study aimed to develop an aquatic decomposition scoring (ADS) method and investigated the predictive value of this method in estimating the postmortem submersion interval (PMSI) of bodies recovered from the North Sea. This method, consisting of an ADS item list and a pictorial reference atlas, showed a high interobserver agreement (Krippendorff's alpha ≥ 0.93) and hence proved to be valid. This scoring method was applied to data, collected from closed cases—cases in which the postmortal submersion interval (PMSI) was known—concerning bodies recovered from the North Sea from 1990 to 2013. Thirty‐eight cases met the inclusion criteria and were scored by quantifying the observed total aquatic decomposition score (TADS). Statistical analysis demonstrated that TADS accurately predicts the PMSI (p < 0.001), confirming that the decomposition process in the North Sea is strongly correlated to time.     

Storm‐Related Postmortem Damage to Skeletal Remains

In April 2011, human skeletons were exposed to heavy storms at the outdoor Anthropology Research Facility (ARF) in Knoxville, Tennessee. Of the approximate 125 skeletons at the ARF in April 2011, 30 donations exhibited postmortem damage that could be attributed to the storms. At least 20 of the affected donations exhibit postmortem damage clearly associated with hailstones due to the oval shape and similar small size of the defects observed. The irregular shape and larger size of other defects may be a product of other falling objects (e.g., tree branches) associated with the storms. Storm‐related damage was observed throughout the skeleton, with the most commonly damaged skeletal elements being the scapula and ilium, but more robust elements (i.e., femora and tibiae) also displayed characteristic features of hailstone damage. Thus, hailstone damage should be considered when forensic practitioners observe unusual postmortem damage in skeletal remains recovered from the outdoor context.     

The Role of Postmortem Computed Tomography in the Evaluation of Strangulation Deaths

We explored the value of postmortem computed tomography (PMCT) to augment autopsy in evaluating strangulation fatalities. A literature search identified 16 studies describing autopsy findings in 576 deaths and two studies describing autopsy and PMCT findings in six deaths. Similar cases were identified from our institution, yielding 130 deaths with autopsy findings and 14 deaths with both autopsy and PMCT findings. The presence of laryngohyoid fracture and soft tissue hemorrhage was compared from autopsy and autopsy+PMCT cases. The detection rates of fractures in autopsy and autopsy+PMCT cases were not significantly different. PMCT identified all fractures observed at autopsy and five fractures not identified. While PMCT may not detect soft tissue injuries in decomposed remains or subtle internal hemorrhages in neck injury, it is equally able to detect bony injuries as autopsy and might surpass autopsy in detecting subtle fractures. We conclude PMCT is useful to supplement autopsy in strangulation cases.     

The Role of Postmortem Cardiac Markers in the Diagnosis of Acute Myocardial Infarction*

Abstract: Sudden cardiac deaths because of acute myocardial infarction (MI) constitute a significant percentage of the caseload for death investigators, coroners, and forensic pathologists. Clinicians use cardiac markers, highly sensitive and specific for myocardial damage, to screen living patients for acute MI; however, to this point, the utility of these markers in the autopsy setting has not been fully established. The current study included 10 decedents, five who died of acute MI, and five subjects who died of noncardiac disease. Samples of pericardial fluid and blood from multiple sites were tested for creatine kinase, creatinine kinase MB, and troponin‐I. Three main conclusions were drawn: the levels of cardiac markers from all patients are significantly higher than the reference range for living patients, there are significant differences in cardiac marker levels between samples from different anatomic locations, and only three cardiac marker/anatomic site combinations were significantly different between the control and study groups.     

Evaluation of Agonal Cardiac Function for Sudden Cardiac Death in Forensic Medicine with Postmortem Brain Natriuretic Peptide (BNP) and NT-proBNP: A Meta-analysis

Sudden cardiac death (SCD) is an unexpected death caused by a sudden loss of cardiac function, which is currently a global public health problem. Evaluation of the agonal cardiac function of the deceased is a quite important task for the diagnosis of SCD in forensic medicine. Brain natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are currently considered as significant biomarkers for the diagnosis of heart failure in both clinical and forensic practices. To investigate the postmortem evaluation roles of postmortem BNP and NT-proBNP levels for SCD, the present study meta-analyzed eight related studies from Embase, Cochrane Library, PubMed, China Biomedical Literature Database, China National Knowledge Infrastructure, and Wanfang Data. Newcastle–Ottawa Quality Assessment Scale was used to assess the quality of the included literature, and the meta-analysis was performed by RevMan 5.3.5 software. Postmortem NT-proBNP in pericardial fluid showed higher levels in the SCD group than that of the non-SCD group with the weighted mean difference = 3665.74, 95% confidence interval: 1812.89–5518.59, and p = 0.0001. However, postmortem levels of BNP in pericardial fluid and NT-proBNP in serum revealed no statistical difference between SCD and non-SCD subjects. The results of present meta-analysis demonstrated that postmortem NT-proBNP in the pericardial fluid could be used as an ancillary indicator for evaluation of agonal cardiac function in forensic medicine.     

Postmortem vitreous Beta-hydroxybutyrate: interpretation in a forensic setting*

Abstract: Vitreous beta‐hydroxybutyrate (BHB) was retrospectively analyzed in 1795 forensic cases using the Pointe Scientific method. Comparison of vitreous BHB with vitreous glucose in 1781 of the cases showed moderately good correlation r = 0.731. Comparison with blood alcohol levels in 1561 of the cases showed no correlation r = ?0.053. Vitreous BHB was a marker of diabetic ketoacidosis when above 6.0 mM with a vitreous glucose over 200 mg/dL. It was an indicator (>50%) for alcoholic ketoacidosis when above 6.0 mM with a vitreous glucose below 200 mg/dL. Recommendations for interpretation of vitreous BHB: <0.4 mM normal; 0.41–1.2 mM slightly elevated, rarely (<1%) of concern; 1.21–2.0 mM moderately elevated, less rarely (2.5%) of concern; 2.01–6.0 mM significantly elevated, frequently of concern (12–48%); >6.0 mM usually (100% in this study) indicated life‐threatening conditions. Vitreous BHB was helpful evaluating cases with ketogenic conditions, especially diabetes and alcoholism.     

Analytical Challenge in Postmortem Toxicology Applied to a Human Body Found into a Lake after Three Years Immersion

The body of a 30‐year‐old woman was found in Como lake at a depth of about 120 meters in her own car after 3 years of immersion. The aim of this study was to evaluate psychoactive drugs as well as alcohol biomarkers in biological matrices. The following analyses were initially performed: GC‐MS systematic toxicological analysis on biological fluids and tissues; GC‐MS analysis of drugs of abuse on pubic hair; direct ethanol metabolite determination in pubic hair by LC‐MS/MS. After 7 years, the samples, that had been stored at ?20°C, were re‐analyzed and submitted to an LC‐MS/MS targeted screening method, using multiple reaction monitoring mode. These analyses detected citalopram (150–3000 ng/mL), desmethylcitalopram (50–2300 ng/mL), clotiapine (20–65 ng/mL), and ethyl glucuronide (97 pg/mg). The methods showed an acceptable reproducibility, and the concentrations of citalopram and desmethylcitalopram calculated through the two analytical techniques did not significantly differ in biological fluids.     

Temperature‐Dependent Postmortem Changes in Human Cardiac Troponin‐T (cTnT): An Approach in Estimation of Time Since Death

Estimation of time of death is an indispensible requirement of every medico‐legal autopsy, but unfortunately, there is not a single method by which it could be determined accurately. This study focused on the temperature‐dependent postmortem degradation of cardiac troponin‐T and its association with postmortem interval (PMI) in human. The analysis involved extraction of the protein, separation by denaturing gel electrophoresis (SDS‐PAGE), and visualization by Western blot using cTnT‐specific monoclonal antibodies. The area of the bands within a lane was quantified by scanning and digitizing the image using Gel Doc (Universal Hood). The results indicate a characteristic banding pattern among human cadavers (n = 6) and a pseudo‐linear relationship between percentage of cTnT degradation and the log of the time since death (r > 0.95), which can be used to estimate the postmortem interval. The data presented demonstrate that this technique can provide an extended time range during which PMI can be more accurately estimated.     

Age Estimation Based on Pulp Cavity to Tooth Volume Ratio Using Postmortem Computed Tomography Images

Pulp cavity size is known to decrease with age and can therefore serve as an indicator for age estimation. Here, we evaluated whether reconstructed images of multidetector‐row computed tomography (MDCT) acquired before forensic autopsy are useful for estimating age at death. Images of 136 mandibular first premolars obtained from bodies of known age at death were analyzed, and the volume of the regions corresponding to pulp cavity and that of the whole tooth were determined using a voxel counting function. The pulp cavity was clearly distinguishable from dental hard tissue on the reconstructed images when using a cutoff value of 1400 Hounsfield units. Regression analysis adjusted for sex showed that estimated age correlated significantly with the pulp cavity to tooth volume ratio (r = 0.76). MDCT is gaining more widespread use in forensic medicine, and analyzing dental images to obtain parameters for age prediction is a practical approach for postmortem identification.