Differential Decomposition Among Pig, Rabbit, and Human Remains.

PubMed

Dautartas, Angela; Kenyhercz, Michael W; Vidoli, Giovanna M; Meadows Jantz, Lee; Mundorff, Amy; Steadman, Dawnie Wolfe

2018-03-30

While nonhuman animal remains are often utilized in forensic research to develop methods to estimate the postmortem interval, systematic studies that directly validate animals as proxies for human decomposition are lacking. The current project compared decomposition rates among pigs, rabbits, and humans at the University of Tennessee's Anthropology Research Facility across three seasonal trials that spanned nearly 2 years. The Total Body Score (TBS) method was applied to quantify decomposition changes and calculate the postmortem interval (PMI) in accumulated degree days (ADD). Decomposition trajectories were analyzed by comparing the estimated and actual ADD for each seasonal trial and by fuzzy cluster analysis. The cluster analysis demonstrated that the rabbits formed one group while pigs and humans, although more similar to each other than either to rabbits, still showed important differences in decomposition patterns. The decomposition trends show that neither nonhuman model captured the pattern, rate, and variability of human decomposition. © 2018 American Academy of Forensic Sciences.

Differential Scavenging Among Pig, Rabbit, and Human Subjects.

PubMed

Steadman, Dawnie Wolfe; Dautartas, Angela; Kenyhercz, Michael W; Jantz, Lee M; Mundorff, Amy; Vidoli, Giovanna M

2018-04-12

Different animal species have been used as proxies for human remains in decomposition studies for decades, although few studies have sought to validate their use in research aimed at estimating the postmortem interval. This study examines 45 pig, rabbit, and human subjects placed in three seasonal trials at the Anthropology Research Facility. In an earlier paper, we found that overall decomposition trends did vary between species that could be due to differential insect and scavenger behavior. This study specifically examines if scavenger behavior differs by carrion species. Daily photographs, game camera photographs, written observations, and Total Body Score (TBS) documented scavenging and decomposition changes. Results show that raccoons were the most commonly observed vertebrate scavenger, that scavenging was most extensive in winter, and that certain human subjects were preferred over other humans and all non-human subjects. Finally, scavenging activity greatly reduces the accuracy of postmortem interval estimates based on TBS. © 2018 American Academy of Forensic Sciences.

Forensic entomology

NASA Astrophysics Data System (ADS)

Amendt, Jens; Krettek, Roman; Zehner, Richard

Necrophagous insects are important in the decomposition of cadavers. The close association between insects and corpses and the use of insects in medicocriminal investigations is the subject of forensic entomology. The present paper reviews the historical background of this discipline, important postmortem processes, and discusses the scientific basis underlying attempts to determine the time interval since death. Using medical techniques, such as the measurement of body temperature or analysing livor and rigor mortis, time since death can only be accurately measured for the first two or three days after death. In contrast, by calculating the age of immature insect stages feeding on a corpse and analysing the necrophagous species present, postmortem intervals from the first day to several weeks can be estimated. These entomological methods may be hampered by difficulties associated with species identification, but modern DNA techniques are contributing to the rapid and authoritative identification of necrophagous insects. Other uses of entomological data include the toxicological examination of necrophagous larvae from a corpse to identify and estimate drugs and toxicants ingested by the person when alive and the proof of possible postmortem manipulations. Forensic entomology may even help in investigations dealing with people who are alive but in need of care, by revealing information about cases of neglect.

Establishing Lower Developmental Thresholds for a Common BlowFly: For Use in Estimating Elapsed Time since Death Using Entomologyical Methods

DTIC Science & Technology

2011-10-01

Abstract …….. Forensic entomology is a science used to estimate a post-mortem interval (PMI). Larvae develop at predictable rates and the time interval...Warren,Jodie; DRDC CSS CR 2011-23; Defence R&D Canada – CSS; October 2011. Introduction or background: Forensic entomology is the study of insects...in Europe since the 1850’s. Forensic entomology is now an integral part of a death investigation when estimating a time since death beyond 72 hours

Temperature-dependent Development of Parasarcophaga similis (Meade 1876) and its Significance in Estimating Postmortem Interval.

PubMed

Yang, Lijun; Wang, Yu; Li, Liangliang; Wang, Jiangfeng; Wang, Min; Zhang, Yingna; Chu, Jun; Liu, Kun; Hou, Yiding; Tao, Luyang

2017-09-01

Flesh flies are commonly found insects on decaying corpses that appears slightly later than blowflies, and their development patterns are significant indicators for minimum postmortem interval (PMI min ) estimation. In this study, the flesh fly Parasarcophaga similis (Meade 1876) was reared at nine constant temperatures ranging from 15°C to 35°C to examine indicators for estimating their age. We generated three development models, including isomorphen diagram, isomegalen diagram, and thermal summation model. Larval body length at different rearing temperatures was fit into an L = a + bT + cT 2 + dT 3 equation with which the relationship between the larval body length (L) and the time after larviposition (T) was confirmed. The pupal stage was categorized into 13 substages according to intrapuparial morphological changes, and a detailed table was generated of the pupal developmental stages at five rearing temperatures, 15°C, 20°C, 25°C, 30°C, and 35°C. This study provides fundamental data in supporting P. similis as an indicator for PMI min estimation. © 2017 American Academy of Forensic Sciences.

Maggot development during morgue storage and its effect on estimating the post-mortem interval.

PubMed

Huntington, Timothy E; Higley, Leon G; Baxendale, Frederick P

2007-03-01

When insect evidence is obtained during autopsy, forensic entomologists make decisions regarding the effects of low-temperature (-1 degrees C to 4 degrees C) storage of the body and associated insects when estimating the post-mortem interval (PMI). To determine the effects of storage in a morgue cooler on the temperature of maggot masses, temperatures inside and outside of body bags containing a human cadaver and porcine cadavers (seven replicates) were measured during storage. Temperatures remained significantly higher (p<0.05) inside of the body bags relative to the cooler, and remained at levels sufficient for maggot feeding and development. If the assumption that no insect development takes place during preautopsy refrigeration is made, potential error rates in PMI estimation of 8.6-12.8% occur. The potential for blow fly larvae to undergo significant development while being stored in the morgue is a possibility that forensic entomologists should consider during an investigation involving samples collected from autopsy. Case and experimental evidence also demonstrate that substantial tissue loss can occur from maggot feeding during morgue storage.

The use of Leptodyctium riparium (Hedw.) Warnst in the estimation of minimum postmortem interval.

PubMed

Lancia, Massimo; Conforti, Federica; Aleffi, Michele; Caccianiga, Marco; Bacci, Mauro; Rossi, Riccardo

2013-01-01

The estimation of the postmortem interval (PMI) is still one of the most challenging issues in forensic investigations, especially in cases in which advanced transformative phenomena have taken place. The dating of skeletal remains is even more difficult and sometimes only a rough determination of the PMI is possible. Recent studies suggest that plant analysis can provide a reliable estimation for skeletal remains dating, when traditional techniques are not applicable. Forensic Botany is a relatively recent discipline that includes many subdisciplines such as Palynology, Anatomy, Dendrochronology, Limnology, Systematic, Ecology, and Molecular Biology. In a recent study, Cardoso et al. (Int J Legal Med 2010;124:451) used botanical evidence for the first time to establish the PMI of human skeletal remains found in a forested area of northern Portugal from the growth rate of mosses and shrub roots. The present paper deals with a case in which the study of the growth rate of the bryophyte Leptodyctium riparium (Hedw.) Warnst, was used in estimating the PMI of some human skeletal remains that were found in a wooded area near Perugia, in Central Italy. © 2012 American Academy of Forensic Sciences.

Similarity analysis of spectra obtained via reflectance spectrometry in legal medicine.

PubMed

Belenki, Liudmila; Sterzik, Vera; Bohnert, Michael

2014-02-01

In the present study, a series of reflectance spectra of postmortem lividity, pallor, and putrefaction-affected skin for 195 investigated cases in the course of cooling down the corpse has been collected. The reflectance spectrometric measurements were stored together with their respective metadata in a MySQL database. The latter has been managed via a scientific information repository. We propose similarity measures and a criterion of similarity that capture similar spectra recorded at corpse skin. We systematically clustered reflectance spectra from the database as well as their metadata, such as case number, age, sex, skin temperature, duration of cooling, and postmortem time, with respect to the given criterion of similarity. Altogether, more than 500 reflectance spectra have been pairwisely compared. The measures that have been used to compare a pair of reflectance curve samples include the Euclidean distance between curves and the Euclidean distance between derivatives of the functions represented by the reflectance curves at the same wavelengths in the spectral range of visible light between 380 and 750 nm. For each case, using the recorded reflectance curves and the similarity criterion, the postmortem time interval during which a characteristic change in the shape of reflectance spectrum takes place is estimated. The latter is carried out via a software package composed of Java, Python, and MatLab scripts that query the MySQL database. We show that in legal medicine, matching and clustering of reflectance curves obtained by means of reflectance spectrometry with respect to a given criterion of similarity can be used to estimate the postmortem interval.

Forensic proteomics for the evaluation of the post-mortem decay in bones.

PubMed

Procopio, Noemi; Williams, Anna; Chamberlain, Andrew T; Buckley, Michael

2018-04-15

Current methods for evaluation the of post-mortem interval (PMI) of skeletal remains suffer from poor accuracy due to the great number of variables that affect the diagenetic process and to the lack of specific guidelines to address this issue. During decomposition, proteins can undergo cumulative decay over the time, resulting in a decrease in the range and abundance of proteins present (i.e., the proteome) in different tissues as well as in an increase of post-translational modifications occurring in these proteins. In this study, we investigate the applicability of bone proteomic analyses to simulated forensic contexts, looking for specific biomarkers that may help the estimation of PMI, as well as evaluate a previously discovered marker for the estimation of biological age. We noticed a reduction of particular plasma and muscle proteins with increasing PMIs, as well as an increased deamidation of biglycan, a protein with a role in modulating bone growth and mineralization. We also corroborated our previous results regarding the use of fetuin-A as a potential biomarker for the estimation of age-at-death, demonstrating the applicability and the great potential that proteomics may have towards forensic sciences. The estimation of the post-mortem interval has a key role in forensic investigations, however nowadays it still suffers from poor reliability, especially when body tissues are heavily decomposed. Here we propose for the first time the application of bone proteomics to the estimation of the time elapsed since death and found several new potential biomarkers to address this, demonstrating the applicability of proteomic analyses to forensic sciences. Copyright © 2018. Published by Elsevier B.V.

Injury-related mortality in South Africa: a retrospective descriptive study of postmortem investigations.

PubMed

Matzopoulos, Richard; Prinsloo, Megan; Pillay-van Wyk, Victoria; Gwebushe, Nomonde; Mathews, Shanaaz; Martin, Lorna J; Laubscher, Ria; Abrahams, Naeemah; Msemburi, William; Lombard, Carl; Bradshaw, Debbie

2015-05-01

To investigate injury-related mortality in South Africa using a nationally representative sample and compare the results with previous estimates. We conducted a retrospective descriptive study of medico-legal postmortem investigation data from mortuaries using a multistage random sample, stratified by urban and non-urban areas and mortuary size. We calculated age-specific and age-standardized mortality rates for external causes of death. Postmortem reports revealed 52,493 injury-related deaths in 2009 (95% confidence interval, CI: 46,930-58,057). Almost half (25,499) were intentionally inflicted. Age-standardized mortality rates per 100,000 population were as follows: all injuries: 109.0 (95% CI: 97.1-121.0); homicide 38.4 (95% CI: 33.8-43.0; suicide 13.4 (95% CI: 11.6-15.2) and road-traffic injury 36.1 (95% CI: 30.9-41.3). Using postmortem reports, we found more than three times as many deaths from homicide and road-traffic injury than had been recorded by vital registration for this period. The homicide rate was similar to the estimate for South Africa from a global analysis, but road-traffic and suicide rates were almost fourfold higher. This is the first nationally representative sample of injury-related mortality in South Africa. It provides more accurate estimates and cause-specific profiles that are not available from other sources.

Forensic Entomology: Evaluating Uncertainty Associated With Postmortem Interval (PMI) Estimates With Ecological Models.

PubMed

Faris, A M; Wang, H-H; Tarone, A M; Grant, W E

2016-05-31

Estimates of insect age can be informative in death investigations and, when certain assumptions are met, can be useful for estimating the postmortem interval (PMI). Currently, the accuracy and precision of PMI estimates is unknown, as error can arise from sources of variation such as measurement error, environmental variation, or genetic variation. Ecological models are an abstract, mathematical representation of an ecological system that can make predictions about the dynamics of the real system. To quantify the variation associated with the pre-appearance interval (PAI), we developed an ecological model that simulates the colonization of vertebrate remains by Cochliomyia macellaria (Fabricius) (Diptera: Calliphoridae), a primary colonizer in the southern United States. The model is based on a development data set derived from a local population and represents the uncertainty in local temperature variability to address PMI estimates at local sites. After a PMI estimate is calculated for each individual, the model calculates the maximum, minimum, and mean PMI, as well as the range and standard deviation for stadia collected. The model framework presented here is one manner by which errors in PMI estimates can be addressed in court when no empirical data are available for the parameter of interest. We show that PAI is a potential important source of error and that an ecological model is one way to evaluate its impact. Such models can be re-parameterized with any development data set, PAI function, temperature regime, assumption of interest, etc., to estimate PMI and quantify uncertainty that arises from specific prediction systems. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

PubMed

van Daalen, Marjolijn A; de Kat, Dorothée S; Oude Grotebevelsborg, Bernice F L; de Leeuwe, Roosje; Warnaar, Jeroen; Oostra, Roelof Jan; M Duijst-Heesters, Wilma L J

2017-03-01

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. © 2017 American Academy of Forensic Sciences.

A preliminary study on postmortem interval estimation of suffocated rats by GC-MS/MS-based plasma metabolic profiling.

PubMed

Sato, Takako; Zaitsu, Kei; Tsuboi, Kento; Nomura, Masakatsu; Kusano, Maiko; Shima, Noriaki; Abe, Shuntaro; Ishii, Akira; Tsuchihashi, Hitoshi; Suzuki, Koichi

2015-05-01

Estimation of postmortem interval (PMI) is an important goal in judicial autopsy. Although many approaches can estimate PMI through physical findings and biochemical tests, accurate PMI calculation by these conventional methods remains difficult because PMI is readily affected by surrounding conditions, such as ambient temperature and humidity. In this study, Sprague-Dawley (SD) rats (10 weeks) were sacrificed by suffocation, and blood was collected by dissection at various time intervals (0, 3, 6, 12, 24, and 48 h; n = 6) after death. A total of 70 endogenous metabolites were detected in plasma by gas chromatography-tandem mass spectrometry (GC-MS/MS). Each time group was separated from each other on the principal component analysis (PCA) score plot, suggesting that the various endogenous metabolites changed with time after death. To prepare a prediction model of a PMI, a partial least squares (or projection to latent structure, PLS) regression model was constructed using the levels of significantly different metabolites determined by variable importance in the projection (VIP) score and the Kruskal-Wallis test (P < 0.05). Because the constructed PLS regression model could successfully predict each PMI, this model was validated with another validation set (n = 3). In conclusion, plasma metabolic profiling demonstrated its ability to successfully estimate PMI under a certain condition. This result can be considered to be the first step for using the metabolomics method in future forensic casework.

An evaluation of soil chemistry in human cadaver decomposition islands: Potential for estimating postmortem interval (PMI).

PubMed

Fancher, J P; Aitkenhead-Peterson, J A; Farris, T; Mix, K; Schwab, A P; Wescott, D J; Hamilton, M D

2017-10-01

Soil samples from the Forensic Anthropology Research Facility (FARF) at Texas State University, San Marcos, TX, were analyzed for multiple soil characteristics from cadaver decomposition islands to a depth of 5centimeters (cm) from 63 human decomposition sites, as well as depths up to 15cm in a subset of 11 of the cadaver decomposition islands plus control soils. Postmortem interval (PMI) of the cadaver decomposition islands ranged from 6 to 1752 days. Some soil chemistry, including nitrate-N (NO 3 -N), ammonium-N (NH 4 -N), and dissolved inorganic carbon (DIC), peaked at early PMI values and their concentrations at 0-5cm returned to near control values over time likely due to translocation down the soil profile. Other soil chemistry, including dissolved organic carbon (DOC), dissolved organic nitrogen (DON), orthophosphate-P (PO 4 -P), sodium (Na + ), and potassium (K + ), remained higher than the control soil up to a PMI of 1752days postmortem. The body mass index (BMI) of the cadaver appeared to have some effect on the cadaver decomposition island chemistry. To estimate PMI using soil chemistry, backward, stepwise multiple regression analysis was used with PMI as the dependent variable and soil chemistry, body mass index (BMI) and physical soil characteristics such as saturated hydraulic conductivity as independent variables. Measures of soil parameters derived from predator and microbial mediated decomposition of human remains shows promise in estimating PMI to within 365days for a period up to nearly five years. This persistent change in soil chemistry extends the ability to estimate PMI beyond the traditionally utilized methods of entomology and taphonomy in support of medical-legal investigations, humanitarian recovery efforts, and criminal and civil cases. Copyright © 2017 Elsevier B.V. All rights reserved.

Necromechanics: Death-induced changes in the mechanical properties of human tissues.

PubMed

Martins, Pedro A L S; Ferreira, Francisca; Natal Jorge, Renato; Parente, Marco; Santos, Agostinho

2015-05-01

After the death phenomenon, the rigor mortis development, characterized by body stiffening, is one of the most evident changes that occur in the body. In this work, the development of rigor mortis was assessed using a skinfold caliper in human cadavers and in live people to measure the deformation in the biceps brachii muscle in response to the force applied by the device. Additionally, to simulate the measurements with the finite element method, a two-dimensional model of an arm section was used. As a result of the experimental procedure, a decrease in deformation with increasing postmortem time was observed, which corresponds to an increase in rigidity. As expected, the deformations for the live subjects were higher. The finite element method analysis showed a correlation between the c1 parameter of the neo-Hookean model in the 4- to 8-h postmortem interval. This was accomplished by adjusting the c1 material parameter in order to simulate the measured experimental displacement. Despite being a preliminary study, the obtained results show that combining the proposed experimental procedure with a numerical technique can be very useful in the study of the postmortem mechanical modifications of human tissues. Moreover, the use of data from living subjects allows us to estimate the time of death paving the way to establish this process as an alternative to the existing techniques. This solution constitutes a portable, non-invasive method of estimating the postmortem interval with direct quantitative measurements using a skinfold caliper. The tools and methods described can be used to investigate the subject and to gain epidemiologic knowledge on rigor mortis phenomenon. © IMechE 2015.

The radiodensity of cerebrospinal fluid and vitreous humor as indicator of the time since death.

PubMed

Koopmanschap, Desirée H J L M; Bayat, Alireza R; Kubat, Bela; de Bakker, Henri M; Prokop, Mathias W M; Klein, Willemijn M

2016-09-01

After death, a series of changes occur naturally in the human body in a fairly regular pattern. These postmortem changes are detectable on postmortem CT scans (PMCT) and may be useful in estimating the postmortem interval (PMI). The purpose of our study is to correlate the PMCT radiodensities of the cerebrospinal fluid (CSF) and vitreous humor (VH) to the PMI. Three patient groups were included: group A consisted of 5 donated cadavers, group B, 100 in-hospital deceased patients, and group C, 12 out-of-hospital forensic cadavers. Group A were scanned every hour for a maximum of 36 h postmortem, and the tympanic temperature was measured prior to each scan. Groups B and C were scanned once after death (PMI range 0.2-63.8 h). Radiodensities of the VH and CSF were measured in Hounsfield units. Correlation between density and PMI was determined using linear regression and the influence of temperature was assessed by a multivariate regression model. Results from group A were validated in groups B and C. Group A showed increasing radiodensity of the CSF and VH over time (r (2) CSF, 0.65). PMI overruled the influence of temperature (r = 0.99 and p = 0.000). Groups B and C showed more diversity, with CSF and VH radiodensities below the mean regression line of Group A. The formula of this upper limit indicated the maximum PMI and was correct for >95 % of the cadavers. The results of group A showed a significant correlation between CSF radiodensity and PMI. The radiodensities in groups B and C were higher than in group A, therefore the maximum PMI can be estimated with the upper 95 % confidence interval of the correlation line of group A.

Forensic use of a subtropical blowfly: the first case indicating minimum postmortem interval (mPMI) in southern Brazil and first record of Sarconesia chlorogaster from a human corpse.

PubMed

Vairo, Karine P; Corrêa, Rodrigo C; Lecheta, Melise C; Caneparo, Maria F; Mise, Kleber M; Preti, Daniel; de Carvalho, Claudio J B; Almeida, Lucia M; Moura, Mauricio O

2015-01-01

Southern Brazil is unique due to its subtropical climate. Here, we report on the first forensic entomology case and the first record of Sarconesia chlorogaster (Wiedemann) in a human corpse in this region. Flies' samples were collected from a body indoors at 20°C. Four species were found, but only Chrysomya albiceps (Wiedemann) and S. chlorogaster were used to estimate the minimum postmortem interval (mPMI). The mPMI was calculated using accumulated degree hour (ADH) and developmental time. The S. chlorogaster puparium collected was light in color, so we used an experiment to establish a more accurate estimate for time since initiation of pupation where we found full tanning after 3 h. Development of C. albiceps at 20°C to the end of the third instar is 7.4 days. The mPMI based on S. chlorogaster (developmental time until the third instar with no more than 3 h of pupae development) was 7.6 days. © 2014 American Academy of Forensic Sciences.

Postmortem succession of gut microbial communities in deceased human subjects

PubMed Central

Hauther, Kathleen A.

2017-01-01

The human microbiome has demonstrated an importance for the health and functioning in living individuals. However, the fate of the microbiome after death is less understood. In addition to a better understanding of microbe-mediated decomposition processes, postmortem succession of human-associated microbial communities has been suggested as a possible forensic tool for estimating time since death, or postmortem interval (PMI). The objective of our study was to document postmortem changes in human gut bacterial communities. Gut microflora were repeatedly sampled from the caeca of cadavers as they decayed under natural environmental conditions. 16S rRNA gene amplicon sequencing revealed that over time, bacterial richness significantly increased (rs = 0.449) while diversity decreased (rs =  − 0.701). The composition of gut bacterial communities changed in a similar manner over time towards a common decay community. OTUs belonging to Bacteroidales (Bacteroides, Parabacteroides) significantly declined while Clostridiales (Clostridium, Anaerosphaera) and the fly-associated Gammaproteobacteria Ignatzschineria and Wohlfahrtiimonas increased. Our examination of human caeca microflora in decomposing cadavers adds to the growing literature on postmortem microbial communities, which will ultimately contribute to a better understanding of decomposition processes. PMID:28626612

Injury-related mortality in South Africa: a retrospective descriptive study of postmortem investigations

PubMed Central

Prinsloo, Megan; Pillay-van Wyk, Victoria; Gwebushe, Nomonde; Mathews, Shanaaz; Martin, Lorna J; Laubscher, Ria; Abrahams, Naeemah; Msemburi, William; Lombard, Carl; Bradshaw, Debbie

2015-01-01

Abstract Objective To investigate injury-related mortality in South Africa using a nationally representative sample and compare the results with previous estimates. Methods We conducted a retrospective descriptive study of medico-legal postmortem investigation data from mortuaries using a multistage random sample, stratified by urban and non-urban areas and mortuary size. We calculated age-specific and age-standardized mortality rates for external causes of death. Findings Postmortem reports revealed 52 493 injury-related deaths in 2009 (95% confidence interval, CI: 46 930–58 057). Almost half (25 499) were intentionally inflicted. Age-standardized mortality rates per 100 000 population were as follows: all injuries: 109.0 (95% CI: 97.1–121.0); homicide 38.4 (95% CI: 33.8–43.0; suicide 13.4 (95% CI: 11.6–15.2) and road-traffic injury 36.1 (95% CI: 30.9–41.3). Using postmortem reports, we found more than three times as many deaths from homicide and road-traffic injury than had been recorded by vital registration for this period. The homicide rate was similar to the estimate for South Africa from a global analysis, but road-traffic and suicide rates were almost fourfold higher. Conclusion This is the first nationally representative sample of injury-related mortality in South Africa. It provides more accurate estimates and cause-specific profiles that are not available from other sources. PMID:26229201

Evaluating the utility of hexapod species for calculating a confidence interval about a succession based postmortem interval estimate.

PubMed

Perez, Anne E; Haskell, Neal H; Wells, Jeffrey D

2014-08-01

Carrion insect succession patterns have long been used to estimate the postmortem interval (PMI) during a death investigation. However, no published carrion succession study included sufficient replication to calculate a confidence interval about a PMI estimate based on occurrence data. We exposed 53 pig carcasses (16±2.5 kg), near the likely minimum needed for such statistical analysis, at a site in north-central Indiana, USA, over three consecutive summer seasons. Insects and Collembola were sampled daily from each carcass for a total of 14 days, by this time each was skeletonized. The criteria for judging a life stage of a given species to be potentially useful for succession-based PMI estimation were (1) nonreoccurrence (observed during a single period of presence on a corpse), and (2) found in a sufficiently large proportion of carcasses to support a PMI confidence interval. For this data set that proportion threshold is 45/53. Of the 266 species collected and identified, none was nonreoccuring in that each showed at least a gap of one day on a single carcass. If the definition of nonreoccurrence is relaxed to include such a single one-day gap the larval forms of Necrophilaamericana, Fanniascalaris, Cochliomyia macellaria, Phormiaregina, and Luciliaillustris satisfied these two criteria. Adults of Creophilus maxillosus, Necrobiaruficollis, and Necrodessurinamensis were common and showed only a few, single-day gaps in occurrence. C.maxillosus, P.regina, and L.illustris displayed exceptional forensic utility in that they were observed on every carcass. Although these observations were made at a single site during one season of the year, the species we found to be useful have large geographic ranges. We suggest that future carrion insect succession research focus only on a limited set of species with high potential forensic utility so as to reduce sample effort per carcass and thereby enable increased experimental replication. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Comparative analysis of bones, mites, soil chemistry, nematodes and soil micro-eukaryotes from a suspected homicide to estimate the post-mortem interval.

PubMed

Szelecz, Ildikó; Lösch, Sandra; Seppey, Christophe V W; Lara, Enrique; Singer, David; Sorge, Franziska; Tschui, Joelle; Perotti, M Alejandra; Mitchell, Edward A D

2018-01-08

Criminal investigations of suspected murder cases require estimating the post-mortem interval (PMI, or time after death) which is challenging for long PMIs. Here we present the case of human remains found in a Swiss forest. We have used a multidisciplinary approach involving the analysis of bones and soil samples collected beneath the remains of the head, upper and lower body and "control" samples taken a few meters away. We analysed soil chemical characteristics, mites and nematodes (by microscopy) and micro-eukaryotes (by Illumina high throughput sequencing). The PMI estimate on hair 14 C-data via bomb peak radiocarbon dating gave a time range of 1 to 3 years before the discovery of the remains. Cluster analyses for soil chemical constituents, nematodes, mites and micro-eukaryotes revealed two clusters 1) head and upper body and 2) lower body and controls. From mite evidence, we conclude that the body was probably brought to the site after death. However, chemical analyses, nematode community analyses and the analyses of micro-eukaryotes indicate that decomposition took place at least partly on site. This study illustrates the usefulness of combining several lines of evidence for the study of homicide cases to better calibrate PMI inference tools.

Predictable weathering of puparial hydrocarbons of necrophagous flies for determining the postmortem interval: a field experiment using Chrysomya rufifacies.

PubMed

Zhu, Guang-Hui; Jia, Zheng-Jun; Yu, Xiao-Jun; Wu, Ku-Sheng; Chen, Lu-Shi; Lv, Jun-Yao; Eric Benbow, M

2017-05-01

Preadult development of necrophagous flies is commonly recognized as an accurate method for estimating the minimum postmortem interval (PMImin). However, once the PMImin exceeds the duration of preadult development, the method is less accurate. Recently, fly puparial hydrocarbons were found to significantly change with weathering time in the field, indicating their potential use for PMImin estimates. However, additional studies are required to demonstrate how the weathering varies among species. In this study, the puparia of Chrysomya rufifacies were placed in the field to experience natural weathering to characterize hydrocarbon composition change over time. We found that weathering of the puparial hydrocarbons was regular and highly predictable in the field. For most of the hydrocarbons, the abundance decreased significantly and could be modeled using a modified exponent function. In addition, the weathering rate was significantly correlated with the hydrocarbon classes. The weathering rate of 2-methyl alkanes was significantly lower than that of alkenes and internal methyl alkanes, and alkenes were higher than the other two classes. For mono-methyl alkanes, the rate was significantly and positively associated with carbon chain length and branch position. These results indicate that puparial hydrocarbon weathering is highly predictable and can be used for estimating long-term PMImin.

Daily thanatomicrobiome changes in soil as an approach of postmortem interval estimation: An ecological perspective.

PubMed

Adserias-Garriga, Joe; Hernández, Marta; Quijada, Narciso M; Rodríguez Lázaro, David; Steadman, Dawnie; Garcia-Gil, Jesús

2017-09-01

Understanding human decomposition is critical for its use in postmortem interval (PMI) estimation, having a significant impact on forensic investigations. In recognition of the need to establish the scientific basis for PMI estimation, several studies on decomposition have been carried out in the last years. The aims of the present study were: (i) to identify soil microbiota communities involved in human decomposition through high-throughput sequencing (HTS) of DNA sequences from the different bacteria, (ii) to monitor quantitatively and qualitatively the decay of such signature species, and (iii) to describe succesional changes in bacterial populations from the early putrefaction state until skeletonization. Three donated individuals to the University of Tennessee FAC were studied. Soil samples around the body were taken from the placement of the donor until advanced decay/dry remains stage. Bacterial DNA extracts were obtained from the samples, HTS techniques were applied and bioinformatic data analysis was performed. The three cadavers showed similar overall successional changes. At the beginning of the decomposition process the soil microbiome consisted of diverse indigenous soil bacterial communities. As decomposition advanced, Firmicutes community abundance increased in the soil during the bloat stage. The growth curve of Firmicutes from human remains can be used to estimate time since death during Tennessee summer conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Estimation of the relative sensitivity of the comparative tuberculin skin test in tuberculous cattle herds subjected to depopulation.

PubMed

Karolemeas, Katerina; de la Rua-Domenech, Ricardo; Cooper, Roderick; Goodchild, Anthony V; Clifton-Hadley, Richard S; Conlan, Andrew J K; Mitchell, Andrew P; Hewinson, R Glyn; Donnelly, Christl A; Wood, James L N; McKinley, Trevelyan J

2012-01-01

Bovine tuberculosis (bTB) is one of the most serious economic animal health problems affecting the cattle industry in Great Britain (GB), with incidence in cattle herds increasing since the mid-1980s. The single intradermal comparative cervical tuberculin (SICCT) test is the primary screening test in the bTB surveillance and control programme in GB and Ireland. The sensitivity (ability to detect infected cattle) of this test is central to the efficacy of the current testing regime, but most previous studies that have estimated test sensitivity (relative to the number of slaughtered cattle with visible lesions [VL] and/or positive culture results) lacked post-mortem data for SICCT test-negative cattle. The slaughter of entire herds ("whole herd slaughters" or "depopulations") that are infected by bTB are occasionally conducted in GB as a last-resort control measure to resolve intractable bTB herd breakdowns. These provide additional post-mortem data for SICCT test-negative cattle, allowing a rare opportunity to calculate the animal-level sensitivity of the test relative to the total number of SICCT test-positive and negative VL animals identified post-mortem (rSe). In this study, data were analysed from 16 whole herd slaughters (748 SICCT test-positive and 1031 SICCT test-negative cattle) conducted in GB between 1988 and 2010, using a bayesian hierarchical model. The overall rSe estimate of the SICCT test at the severe interpretation was 85% (95% credible interval [CI]: 78-91%), and at standard interpretation was 81% (95% CI: 70-89%). These estimates are more robust than those previously reported in GB due to inclusion of post-mortem data from SICCT test-negative cattle.

Estimation of the Relative Sensitivity of the Comparative Tuberculin Skin Test in Tuberculous Cattle Herds Subjected to Depopulation

PubMed Central

Karolemeas, Katerina; de la Rua-Domenech, Ricardo; Cooper, Roderick; Goodchild, Anthony V.; Clifton-Hadley, Richard S.; Conlan, Andrew J. K.; Mitchell, Andrew P.; Hewinson, R. Glyn; Donnelly, Christl A.; Wood, James L. N.; McKinley, Trevelyan J.

2012-01-01

Bovine tuberculosis (bTB) is one of the most serious economic animal health problems affecting the cattle industry in Great Britain (GB), with incidence in cattle herds increasing since the mid-1980s. The single intradermal comparative cervical tuberculin (SICCT) test is the primary screening test in the bTB surveillance and control programme in GB and Ireland. The sensitivity (ability to detect infected cattle) of this test is central to the efficacy of the current testing regime, but most previous studies that have estimated test sensitivity (relative to the number of slaughtered cattle with visible lesions [VL] and/or positive culture results) lacked post-mortem data for SICCT test-negative cattle. The slaughter of entire herds (“whole herd slaughters” or “depopulations”) that are infected by bTB are occasionally conducted in GB as a last-resort control measure to resolve intractable bTB herd breakdowns. These provide additional post-mortem data for SICCT test-negative cattle, allowing a rare opportunity to calculate the animal-level sensitivity of the test relative to the total number of SICCT test-positive and negative VL animals identified post-mortem (rSe). In this study, data were analysed from 16 whole herd slaughters (748 SICCT test-positive and 1031 SICCT test-negative cattle) conducted in GB between 1988 and 2010, using a Bayesian hierarchical model. The overall rSe estimate of the SICCT test at the severe interpretation was 85% (95% credible interval [CI]: 78–91%), and at standard interpretation was 81% (95% CI: 70–89%). These estimates are more robust than those previously reported in GB due to inclusion of post-mortem data from SICCT test-negative cattle. PMID:22927952

The Sun Health Research Institute Brain Donation Program: Description and Eexperience, 1987–2007

PubMed Central

Sue, Lucia I.; Walker, Douglas G.; Roher, Alex E.; Lue, LihFen; Vedders, Linda; Connor, Donald J.; Sabbagh, Marwan N.; Rogers, Joseph

2008-01-01

The Brain Donation Program at Sun Health Research Institute has been in continual operation since 1987, with over 1000 brains banked. The population studied primarily resides in the retirement communities of northwest metropolitan Phoenix, Arizona. The Institute is affiliated with Sun Health, a nonprofit community-owned and operated health care provider. Subjects are enrolled prospectively to allow standardized clinical assessments during life. Funding comes primarily from competitive grants. The Program has made short postmortem brain retrieval a priority, with a 2.75-h median postmortem interval for the entire collection. This maximizes the utility of the resource for molecular studies; frozen tissue from approximately 82% of all cases is suitable for RNA studies. Studies performed in-house have shown that, even with very short postmortem intervals, increasing delays in brain retrieval adversely affect RNA integrity and that cerebrospinal fluid pH increases with postmortem interval but does not predict tissue viability. PMID:18347928

Generalized additive models and Lucilia sericata growth: assessing confidence intervals and error rates in forensic entomology.

PubMed

Tarone, Aaron M; Foran, David R

2008-07-01

Forensic entomologists use blow fly development to estimate a postmortem interval. Although accurate, fly age estimates can be imprecise for older developmental stages and no standard means of assigning confidence intervals exists. Presented here is a method for modeling growth of the forensically important blow fly Lucilia sericata, using generalized additive models (GAMs). Eighteen GAMs were created to predict the extent of juvenile fly development, encompassing developmental stage, length, weight, strain, and temperature data, collected from 2559 individuals. All measures were informative, explaining up to 92.6% of the deviance in the data, though strain and temperature exerted negligible influences. Predictions made with an independent data set allowed for a subsequent examination of error. Estimates using length and developmental stage were within 5% of true development percent during the feeding portion of the larval life cycle, while predictions for postfeeding third instars were less precise, but within expected error.

[Realization of an adaptive method of simulating the process of temperature change of a cadaver on a microcomputer].

PubMed

Shved, E F; Novikov, P I; Vlasov, A Iu

1989-01-01

Programme based on mathematical model of the process of dead body temperature changing was developed for estimation of postmortem interval. Automatic retrieval of problem solution was performed on programmable microcalculators of "Electronica MK-61" type using adaptive approach. Diagnostical accuracy in case of dead body being preserved in permanent cooling conditions is +/- 3%.

The use of Megaselia abdita (Diptera: Phoridae) in forensic entomology.

PubMed

Manlove, J D; Disney, R H L

2008-02-25

This case study demonstrates the importance of the Phorid, Megaselia abdita (Schmitz), as an indicator for post-mortem interval estimation in criminal investigations involving forensic entomology where it is usually the more frequently occurring Calliphorids that are most useful. A case example is discussed where the temperatures were low for the period of time the deceased was missing.

Recreating Death's Acre in the School Yard: Using Pig Carcasses as Model Corpses to Teach Concepts of Forensic Entomology & Ecological Succession

ERIC Educational Resources Information Center

Schoenly, Kenneth G.; Haskell, Neal H.; Mills, David K.; Bieme-Ndi, Carine; Larsen, Kristie; Lee, Yer

2006-01-01

In this article, the authors describe how to construct a mock crime scene, acquire a pig carcass, sample its arthropod fauna, integrate photographic, climatic and arthropod successional data, and estimate the postmortem interval (PMI) from insect successional timetables. The experimental layout described in this article represents the untreated…

The development of a post-mortem interval estimation for human remains found on land in the Netherlands.

PubMed

Gelderman, H T; Boer, L; Naujocks, T; IJzermans, A C M; Duijst, W L J M

2018-05-01

The decomposition process of human remains can be used to estimate the post-mortem interval (PMI), but decomposition varies due to many factors. Temperature is believed to be the most important and can be connected to decomposition by using the accumulated degree days (ADD). The aim of this research was to develop a decomposition scoring method and to develop a formula to estimate the PMI by using the developed decomposition scoring method and ADD.A decomposition scoring method and a Book of Reference (visual resource) were made. Ninety-one cases were used to develop a method to estimate the PMI. The photographs were scored using the decomposition scoring method. The temperature data was provided by the Royal Netherlands Meteorological Institute. The PMI was estimated using the total decomposition score (TDS) and using the TDS and ADD. The latter required an additional step, namely to calculate the ADD from the finding date back until the predicted day of death.The developed decomposition scoring method had a high interrater reliability. The TDS significantly estimates the PMI (R 2  = 0.67 and 0.80 for indoor and outdoor bodies, respectively). When using the ADD, the R 2 decreased to 0.66 and 0.56.The developed decomposition scoring method is a practical method to measure decomposition for human remains found on land. The PMI can be estimated using this method, but caution is advised in cases with a long PMI. The ADD does not account for all the heat present in a decomposing remain and is therefore a possible bias.

Dynamics of Necrophagous Insect and Tissue Bacteria for Postmortem Interval Estimation During the Warm Season in Romania.

PubMed

Iancu, Lavinia; Sahlean, Tiberiu; Purcarea, Cristina

2016-01-01

The estimation of postmortem interval (PMI) is affected by several factors including the cause of death, the place where the body lay after death, and the weather conditions during decomposition. Given the climatic differences among biogeographic locations, the understanding of necrophagous insect species biology and ecology is required when estimating PMI. The current experimental model was developed in Romania during the warm season in an outdoor location. The aim of the study was to identify the necrophagous insect species diversity and dynamics, and to detect the bacterial species present during decomposition in order to determine if their presence or incidence timing could be useful to estimate PMI. The decomposition process of domestic swine carcasses was monitored throughout a 14-wk period (10 July-10 October 2013), along with a daily record of meteorological parameters. The chronological succession of necrophagous entomofauna comprised nine Diptera species, with the dominant presence of Chrysomya albiceps (Wiedemann 1819) (Calliphoridae), while only two Coleoptera species were identified, Dermestes undulatus (L. 1758) and Creophilus maxillosus Brahm 1970. The bacterial diversity and dynamics from the mouth and rectum tissues, and third-instar dipteran larvae were identified using denaturing gradient gel electrophoresis analysis and sequencing of bacterial 16S rRNA gene fragments. Throughout the decomposition process, two main bacterial chronological groups were differentiated, represented by Firmicutes and Gammaproteobacteria. Twenty-six taxa from the rectal cavity and 22 from the mouth cavity were identified, with the dominant phylum in both these cavities corresponding to Firmicutes. The present data strengthen the postmortem entomological and microbial information for the warm season in this temperate-continental area, as well as the role of microbes in carcass decomposition. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A Machine Learning Approach for Using the Postmortem Skin Microbiome to Estimate the Postmortem Interval

PubMed Central

Johnson, Hunter R.; Trinidad, Donovan D.; Guzman, Stephania; Khan, Zenab; Parziale, James V.; DeBruyn, Jennifer M.

2016-01-01

Research on the human microbiome, the microbiota that live in, on, and around the human person, has revolutionized our understanding of the complex interactions between microbial life and human health and disease. The microbiome may also provide a valuable tool in forensic death investigations by helping to reveal the postmortem interval (PMI) of a decedent that is discovered after an unknown amount of time since death. Current methods of estimating PMI for cadavers discovered in uncontrolled, unstudied environments have substantial limitations, some of which may be overcome through the use of microbial indicators. In this project, we sampled the microbiomes of decomposing human cadavers, focusing on the skin microbiota found in the nasal and ear canals. We then developed several models of statistical regression to establish an algorithm for predicting the PMI of microbial samples. We found that the complete data set, rather than a curated list of indicator species, was preferred for training the regressor. We further found that genus and family, rather than species, are the most informative taxonomic levels. Finally, we developed a k-nearest- neighbor regressor, tuned with the entire data set from all nasal and ear samples, that predicts the PMI of unknown samples with an average error of ±55 accumulated degree days (ADD). This study outlines a machine learning approach for the use of necrobiome data in the prediction of the PMI and thereby provides a successful proof-of- concept that skin microbiota is a promising tool in forensic death investigations. PMID:28005908

How should forensic anthropologists correct national weather service temperature data for use in estimating the postmortem interval?

PubMed

Dabbs, Gretchen R

2015-05-01

This study examines the correlation between site-specific and retrospectively collected temperature data from the National Weather Service (NWS) over an extended time period. Using iButtonLink thermochrons (model DS1921G), hourly temperature readings were collected at 15 sites (1 validation; 14 experimental) from December 2010 to January 2012. Comparison between the site-specific temperature data and data retrieved from an official reporter of NWS temperature data shows statistically significant differences between the two in 71.4% (10/14) of cases. The difference ranged between 0.04 and 2.81°C. Examination of both regression and simple adjustment of the mean difference over extended periods (1, 2, 3, 4, 5, 6, & 9 months) suggests that on the timescale typical in forensic anthropology cases neither method of correction is consistent or reliable and that forensic anthropologists would be better suited using uncorrected NWS temperature data when the postmortem interval is extended. © 2015 American Academy of Forensic Sciences.

Virtual forensic entomology: improving estimates of minimum post-mortem interval with 3D micro-computed tomography.

PubMed

Richards, Cameron S; Simonsen, Thomas J; Abel, Richard L; Hall, Martin J R; Schwyn, Daniel A; Wicklein, Martina

2012-07-10

We demonstrate how micro-computed tomography (micro-CT) can be a powerful tool for describing internal and external morphological changes in Calliphora vicina (Diptera: Calliphoridae) during metamorphosis. Pupae were sampled during the 1st, 2nd, 3rd and 4th quarter of development after the onset of pupariation at 23 °C, and placed directly into 80% ethanol for preservation. In order to find the optimal contrast, four batches of pupae were treated differently: batch one was stained in 0.5M aqueous iodine for 1 day; two for 7 days; three was tagged with a radiopaque dye; four was left unstained (control). Pupae stained for 7d in iodine resulted in the best contrast micro-CT scans. The scans were of sufficiently high spatial resolution (17.2 μm) to visualise the internal morphology of developing pharate adults at all four ages. A combination of external and internal morphological characters was shown to have the potential to estimate the age of blowfly pupae with a higher degree of accuracy and precision than using external morphological characters alone. Age specific developmental characters are described. The technique could be used as a measure to estimate a minimum post-mortem interval in cases of suspicious death where pupae are the oldest stages of insect evidence collected. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

The influence of preburial insect access on the decomposition rate.

PubMed

Bachmann, Jutta; Simmons, Tal

2010-07-01

This study compared total body score (TBS) in buried remains (35 cm depth) with and without insect access prior to burial. Sixty rabbit carcasses were exhumed at 50 accumulated degree day (ADD) intervals. Weight loss, TBS, intra-abdominal decomposition, carcass/soil interface temperature, and below-carcass soil pH were recorded and analyzed. Results showed significant differences (p < 0.001) in decomposition rates between carcasses with and without insect access prior to burial. An approximately 30% enhanced decomposition rate with insects was observed. TBS was the most valid tool in postmortem interval (PMI) estimation. All other variables showed only weak relationships to decomposition stages, adding little value to PMI estimation. Although progress in estimating the PMI for surface remains has been made, no previous studies have accomplished this for buried remains. This study builds a framework to which further comparable studies can contribute, to produce predictive models for PMI estimation in buried human remains.

Potential use of bacterial community succession for estimating post-mortem interval as revealed by high-throughput sequencing

PubMed Central

Guo, Juanjuan; Fu, Xiaoliang; Liao, Huidan; Hu, Zhenyu; Long, Lingling; Yan, Weitao; Ding, Yanjun; Zha, Lagabaiyila; Guo, Yadong; Yan, Jie; Chang, Yunfeng; Cai, Jifeng

2016-01-01

Decomposition is a complex process involving the interaction of both biotic and abiotic factors. Microbes play a critical role in the process of carrion decomposition. In this study, we analysed bacterial communities from live rats and rat remains decomposed under natural conditions, or excluding sarcosaphagous insect interference, in China using Illumina MiSeq sequencing of 16S rRNA gene amplicons. A total of 1,394,842 high-quality sequences and 1,938 singleton operational taxonomic units were obtained. Bacterial communities showed notable variation in relative abundance and became more similar to each other across body sites during the decomposition process. As decomposition progressed, Proteobacteria (mostly Gammaproteobacteria) became the predominant phylum in both the buccal cavity and rectum, while Firmicutes and Bacteroidetes in the mouth and rectum, respectively, gradually decreased. In particular, the arrival and oviposition of sarcosaphagous insects had no obvious influence on bacterial taxa composition, but accelerated the loss of biomass. In contrast to the rectum, the microbial community structure in the buccal cavity of live rats differed considerably from that of rats immediately after death. Although this research indicates that bacterial communities can be used as a “microbial clock” for the estimation of post-mortem interval, further work is required to better understand this concept. PMID:27052375

Usability of Immunohistochemistry in Forensic Samples With Varying Decomposition.

PubMed

Lesnikova, Iana; Schreckenbach, Marc Niclas; Kristensen, Maria Pihlmann; Papanikolaou, Liv Lindegaard; Hamilton-Dutoit, Stephen

2018-05-24

Immunohistochemistry (IHC) is an important diagnostic tool in anatomic and surgical pathology but is used less frequently in forensic pathology. Degradation of tissue because of postmortem decomposition is believed to be a major limiting factor, although it is unclear what impact such degradation actually has on IHC staining validity. This study included 120 forensic autopsy samples of liver, lung, and brain tissues obtained for diagnostic purposes. The time from death to autopsy ranged between 1 and more than 14 days. Samples were prepared using the tissue microarray technique. The antibodies chosen for the study included KL1 (for staining bile duct epithelium), S100 (for staining glial cells and myelin), vimentin (for endothelial cells in cerebral blood vessels), and CD45 (for pulmonary lymphocytes). Slides were evaluated by light microscopy. Immunohistochemistry reactions were scored according to a system based on the extent and intensity of the positive stain. An overall correlation between the postmortem interval and the IHC score for all tissue samples was found. Samples from decedents with a postmortem interval of 1 to 3 days showed positive staining with all antibodies, whereas samples from decedents with a longer postmortem interval showed decreased staining rates. Our results suggest that IHC analysis can be successfully used for postmortem diagnosis in a range of autopsy samples showing lesser degrees of decomposition.

Postmortem Cholesterol Levels in Peripheral Nerve Tissue: Preliminar Considerations on Interindividual and Intraindividual Variation.

PubMed

Vacchiano, Giuseppe; Luna Maldonado, Aurelio; Matas Ros, Maria; Fiorenza, Elisa; Silvestre, Angela; Simonetti, Biagio; Pieri, Maria

2018-06-01

The study reports the evolution of the demyelinization process based on cholesterol ([CHOL]) levels quantified in median nerve samples and collected at different times-from death from both right and left wrists. The statistical data show that the phenomenon evolves differently in the right and left nerves. Such a difference can reasonably be attributed to a different multicenter evolution of the demyelinization. For data analysis, the enrolled subjects were grouped by similar postmortem intervals (PMIs), considering 3 intervals: PMI < 48 hours, 48 hours < PMI < 78 hours, and PMI > 78 hours. Data obtained from tissue dissected within 48 hours of death allowed for a PMI estimation according to the following equations: PMI = 0.000 + 0.7623 [CHOL]right (R = 0.581) for the right wrist and PMI = 0.000 + 0.8911 [CHOL]left (R = 0.794) for the left wrist.At present, this correlation cannot be considered to be definitive because of the limitation of the small size of the samples analyzed, because the differences in the sampling time and the interindividual and intraindividual variation may influence the demyelinization process.

Dynamics of the oral microbiota as a tool to estimate time since death.

PubMed

Adserias-Garriga, J; Quijada, N M; Hernandez, M; Rodríguez Lázaro, D; Steadman, D; Garcia-Gil, L J

2017-06-27

The oral cavity harbors one of the most diverse microbiomes in the human body. It has been shown to be the second most complex in the body after the gastrointestinal tract. Upon death, the indigenous microorganisms lead to the decomposition of the carcass. Therefore, the oral cavity and gastrointestinal tract microbiomes play a key role in human decomposition. The aim of the present study is to monitor the microbiome of decaying bodies on a daily basis and to identify signature bacterial taxa, that can improve postmortem interval estimation. Three individuals (one male and two female) donated to the University of Tennessee Forensic Anthropology Center for the W.M. Bass Donated Skeletal Collection were studied. Oral swab samples were taken daily throughout the different stages of cadaveric putrefaction. DNA was extracted and analyzed by next-generation sequencing techniques. The three cadavers showed similar overall successional changes during the decomposition process. Firmicutes and Actinobacteria are the predominant phyla in the fresh stage. The presence of Tenericutes corresponds to bloat stage. Firmicutes is the predominant phylum in advanced decay, but the Firmicutes community is a different one from the predominant Firmicutes of the fresh stage. This study depicts the thanatomicrobiome successional changes in the oral cavity, and highlights its potential use in forensic cases as a quantitative and objective approach to estimate postmortem interval, from an ecological rationale. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Cardiac troponin T determination by a highly sensitive assay in postmortem serum and pericardial fluid.

PubMed

González-Herrera, Lucas; Valenzuela, Aurora; Ramos, Valentín; Blázquez, Antonia; Villanueva, Enrique

2016-06-01

The main objective of this study was to test, for the first time, a highly sensitive cardiac troponin T (cTnThs) assay in postmortem serum and pericardial fluid and to evaluate cardiac troponin T (cTnT) levels and their stability after death at different postmortem intervals, in an attempt to determine the viability of the cTnThs assay in the postmortem diagnosis of the cause of death. cTnT levels were determined in serum and pericardial fluid samples taken from 58 cadavers at known postmortem intervals, whose causes of death were categorized into the following groups: (1) sudden cardiac deaths, (2) multiple trauma, (3) mechanical asphyxia, and (4) other natural deaths. cTnT was determined by inmunoassay, using the Troponin T highly sensitive STAT assay (Roche(®)). Average cTnT levels measured by a highly sensitive assay in postmortem serum were markedly higher than clinical serum levels. Moreover, similar results, higher cTnT levels in postmortem pericardial fluid, were obtained when compared to levels found in pericardial fluid taken from two living patients during coronary artery bypass surgery. cTnT levels in both postmortem fluids remained stable for up to 34 h after death. No differences in cTnT levels in either postmortem fluid by sex and age were detected. Levels of cTnT found in pericardial fluid in the other natural deaths group were significantly lower than the cTnT levels found in that postmortem fluid from any of the other causes of death groups. It is therefore reasonable to conclude that determination of cTnT by a highly sensitive assay in pericardial fluid can provide forensic pathologists with a complementary test to the diagnosis of cause of death.

Quantification of nitrogenous bases, DNA and Collagen type I for the estimation of the postmortem interval in bone remains.

PubMed

Pérez-Martínez, Cristina; Pérez-Cárceles, María D; Legaz, Isabel; Prieto-Bonete, Gemma; Luna, Aurelio

2017-12-01

Estimating the postmortem interval (PMI) is an important goal in forensic medicine and continues to be one of the most difficult tasks of the forensic investigator. Few accurate methods exist to determine the time since death of skeletonized human remains due to the great number of intrinsic and external factors that may alter the normal course of postmortem change. The purpose of this research was to assess the usefulness of various biochemical parameters, such as nitrogenous bases (adenine, guanine, purines, cytosine, thymine, pyrimidines, hypoxanthine and xanthine), DNA and Collagen Type I peptides to estimate PMI. These parameters were analysed in cortical bone for the establishment of data in a total of 80 long bones of 80 corpses (50 males, 30 females) with a mean age of 68.31 years (S.D.=18.021, range=20-97). The bones were removed from the cement niches of a cemetery in Murcia (south-eastern Spain), where they had lain for between 5 and 47 years (mean time 23.83 years, S.D.=10.85). Our results show a significant decrease in adenine (p=0.0004), guanine (p=0.0001), purines (p=0.0001), cytosine (p=0.0001), thymine (p=0.0226), pyrimidines (p=0.0002) and the number of peptides of Collagen type I (p=0.0053) in those with a PMI≥20 years. In a curvilinear regression analysis the results show that 30.6% of the variable PMI could be explained by guanine concentration, in bones with a PMI<20 years, while in cases of a PMI≥20 years, the variable that best explained membership of this group was adenine (38.0%). In the discriminant analysis applied to the all the variables as a function of PMI when two groups were established, 86.7% of the cases were correctly classified. These results show that the quantification of Collagen type I proteins and nitrogenous bases could be used as a complementary tool, together with other analyses, in the estimation of PMI. Copyright © 2017 Elsevier B.V. All rights reserved.

Using bacterial and necrophagous insect dynamics for post-mortem interval estimation during cold season: Novel case study in Romania.

PubMed

Iancu, Lavinia; Carter, David O; Junkins, Emily N; Purcarea, Cristina

2015-09-01

Considering the biogeographical characteristics of forensic entomology, and the recent development of forensic microbiology as a complementary approach for post-mortem interval estimation, the current study focused on characterizing the succession of necrophagous insect species and bacterial communities inhabiting the rectum and mouth cavities of swine (Sus scrofa domesticus) carcasses during a cold season outdoor experiment in an urban natural environment of Bucharest, Romania. We monitored the decomposition process of three swine carcasses during a 7 month period (November 2012-May 2013) corresponding to winter and spring periods of a temperate climate region. The carcasses, protected by wire cages, were placed on the ground in a park type environment, while the meteorological parameters were constantly recorded. The succession of necrophagous Diptera and Coleoptera taxa was monitored weekly, both the adult and larval stages, and the species were identified both by morphological and genetic characterization. The structure of bacterial communities from swine rectum and mouth tissues was characterized during the same time intervals by denaturing gradient gel electrophoresis (DGGE) and sequencing of 16S rRNA gene fragments. We observed a shift in the structure of both insect and bacterial communities, primarily due to seasonal effects and the depletion of the carcass. A total of 14 Diptera and 6 Coleoptera species were recorded on the swine carcasses, from which Calliphora vomitoria and C. vicina (Diptera: Calliphoridae), Necrobia violacea (Coleoptera: Cleridae) and Thanatophilus rugosus (Coleoptera: Silphidae) were observed as predominant species. The first colonizing wave, primarily Calliphoridae, was observed after 15 weeks when the temperature increased to 13°C. This was followed by Muscidae, Fanniidae, Anthomyiidae, Sepsidae and Piophilidae. Families belonging to Coleoptera Order were observed at week 18 when temperatures raised above 18°C, starting with Cleridae, Silphidae, and followed by Histeridae, Staphylinidae and Dermestidae. For bacteria, 53 taxa belonging to phyla Proteobacteria (Gammaproteobacteria, Betaproteobacteria), Firmicutes and Bacteroidetes were identified from the mouth cavity (36 OTUs) and rectum cavity (17 OTUs). These shifts in insect and bacterial communities indicated their complementary role in the carcass decomposition process. These results represent the first forensic entomological and microbiological survey in Romania. This study shows the value of forensic entomology as a tool for forensic investigations in Romania and neighboring areas with similar biogeographical characteristics. Moreover, this study represents a novel approach for understanding taphonomy and estimating post-mortem interval during cold season by combining entomological and microbiological methods. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A comparative in situ decomposition study using still born piglets and leaf litter from a deciduous forest.

PubMed

Olakanye, Ayodeji O; Nelson, Andrew; Ralebitso-Senior, T Komang

2017-07-01

A cadaver and dead plant organic matter, or litter, are rich energy sources that undergo a complex decomposition process, which impact the surrounding environmental microbiota. Advances in molecular microbiology techniques, with study of the 16S RNA genes, in particular, have highlighted the application of forensic ecogenomics in addressing key knowledge gaps. To investigate subsurface microbiome shifts as a novel tool to establish "postmortem microbial clock" and augment postmortem interval (PMI) and time-since-burial estimations, an in situ study with triplicate underground burials of piglets as human taphonomic proxies and Quercus robur leaf litter was monitored for 270 days. Changes in microbial community structure and composition were related directly to changes in seasonal temperature, with microbial shifts more pronounced during the summer. For example, Methylococcaceae could be used as seasonal bacterial indicators, from winter to summer, in establishing postmortem microbial clock for this site. Furthermore, Methylophilaceae (Methylophilales order) and Anaerolineaceae would differentiate for the piglet and leaf litter soils, respectively, 180 days after internment. Copyright © 2017 Elsevier B.V. All rights reserved.

[Application and progress of RNA in forensic science].

PubMed

Gao, Lin-Lin; Li, You-Ying; Yan, Jiang-Wei; Liu, Ya-Cheng

2011-12-01

With the development of molecular biology, the evidences of genetics has been used widely in forensic sciences. DNA technology has played an important role in individual identification and paternity testing, RNA technology is showing more and more wide application in prospect. This article reviews the application and progress of RNA in forensic science including estimation of postmortem interval, bloodstain age, wound age, as well as determination of cause of death and the source of body fluids.

[Biological characteristics of calliphoridae and its application in forensic medicine].

PubMed

Zhao, Boa; Wen, Charn; Qi, Li-Li; Wang, He; Wang, Ji

2013-12-01

Diptera Calliphoridae is the first major kind of flies that appears on the decomposed corpses. In forensic entomology, according to the living characteristics of Calliphoridae flies, we could accurately estimate postmortem interval (PMI) in a murder or unidentified case and could provide useful clues to solve the case. This paper introduces the characteristics of the biology and morphology of Diptera Calliphoridae, and reviews the combined application of forensic entomology, molecular biology, mathematical morphology and toxicology.

Quantification of interstitial fluid on whole body CT: comparison with whole body autopsy.

PubMed

Lo Gullo, Roberto; Mishra, Shelly; Lira, Diego A; Padole, Atul; Otrakji, Alexi; Khawaja, Ranish Deedar Ali; Pourjabbar, Sarvenaz; Singh, Sarabjeet; Shepard, Jo-Anne O; Digumarthy, Subba R; Kalra, Mannudeep K; Stone, James R

2015-12-01

Interstitial fluid accumulation can occur in pleural, pericardial, and peritoneal spaces, and subcutaneous tissue planes. The purpose of the study was to assess if whole body CT examination in a postmortem setting could help determine the presence and severity of third space fluid accumulation in the body. Our study included 41 human cadavers (mean age 61 years, 25 males and 16 females) who had whole-body postmortem CT prior to autopsy. All bodies were maintained in the morgue in the time interval between death and autopsy. Two radiologists reviewed the whole-body CT examinations independently to grade third space fluid in the pleura, pericardium, peritoneum, and subcutaneous space using a 5-point grading system. Qualitative CT grading for third space fluid was correlated with the amount of fluid found on autopsy and the quantitative CT fluid volume, estimated using a dedicated software program (Volume, Syngo Explorer, Siemens Healthcare). Moderate and severe peripheral edema was seen in 16/41 and 7/41 cadavers respectively. It is not possible to quantify anasarca at autopsy. Correlation between imaging data for third space fluid and the quantity of fluid found during autopsy was 0.83 for pleural effusion, 0.4 for pericardial effusion and 0.9 for ascites. The degree of anasarca was significantly correlated with the severity of ascites (p < 0.0001) but not with pleural or pericardial effusion. There was strong correlation between volumetric estimation and qualitative grading for anasarca (p < 0.0001) and pleural effusion (p < 0.0001). Postmortem CT can help in accurate detection and quantification of third space fluid accumulation. The quantity of ascitic fluid on postmortem CT can predict the extent of anasarca.

Postmortem ICD interrogation in mode of death classification.

PubMed

Nikolaidou, Theodora; Johnson, Miriam J; Ghosh, Justin M; Marincowitz, Carl; Shah, Saumil; Lammiman, Michael J; Schilling, Richard J; Clark, Andrew L

2018-04-01

The definition of sudden death due to arrhythmia relies on the time interval between onset of symptoms and death. However, not all sudden deaths are due to arrhythmia. In patients with an implantable cardioverter defibrillator (ICD), postmortem device interrogation may help better distinguish the mode of death compared to a time-based definition alone. This study aims to assess the proportion of "sudden" cardiac deaths in patients with an ICD that have confirmed arrhythmia. We conducted a literature search for studies using postmortem ICD interrogation and a time-based classification of the mode of death. A modified QUADAS-2 checklist was used to assess risk of bias in individual studies. Outcome data were pooled where sufficient data were available. Our search identified 22 studies undertaken between 1982 and 2015 with 23,600 participants. The pooled results (excluding studies with high risk of bias) suggest that ventricular arrhythmias are present at the time of death in 76% of "sudden" deaths (95% confidence interval [CI] 67-85; range 42-88). Postmortem ICD interrogation identifies 24% of "sudden" deaths to be nonarrhythmic. Postmortem device interrogation should be considered in all cases of unexplained sudden cardiac death. © 2018 Wiley Periodicals, Inc.

An initial study on the succession of sarcosaprophagous Diptera (Insecta) on carrion in the southeastern Iberian peninsula.

PubMed

Arnaldos, I; Romera, E; García, M D; Luna, A

2001-01-01

We present the results of the first study concerning Diptera carried out on the sarcosaprophagous fauna of southeastern Spain. This work represents the first attempt to describe dipteran sarcosaprophagous fauna in the Iberian peninsula, the seasonal succession, main features of the population dynamics and the main taxa useful for estimation of the post-mortem interval. The results of this study could be very useful for further forensic case work in the west Mediterranean area.

Feasibility, diagnostic validity and limits of postmortem evaluation of a newborn infant following an extremely prolonged freezing interval: a thanatological case study.

PubMed

Krajčovič, Jozef; Janík, Martin; Novomeský, František; Straka, Lubomír; Hejna, Petr

2014-11-01

In forensic assessment, denial and concealment of pregnancy has wide-ranging implications including criminal abortions, extramural deliveries, concealment of birth, newborn infant abandonment or even neonaticide. Clarification of whether a newborn was born alive is the most important factor when evaluating an abandoned neonate or concealment of birth. Other points that need to be addressed are determination of viability and maturity of the newborn infant, and the identity of the mother. A prolonged postmortem interval following illegal disposal of a dead body often leads to advanced decomposition, making postmortem elucidation difficult. We report an exceptionally uncommon autopsy case of a well-preserved female newborn, which was accidentally found after eight years in a home freezer. Despite the prolonged postmortem interval, tissue preservation was sufficient for a meaningful autopsy including a comprehensive histopathological study. The purpose of the present investigations was to expand our understanding of thanatological processes, as well as detectability of particular histological findings on the remains of a newborn after extremely prolonged storage in an artificially frozen environment. In addition, this article discusses forensically important issues regarding concealment of newborn infant under specific conditions. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Study of chemiluminescence measured by luminometry and its application in the estimation of postmortem interval of bone remains.

PubMed

Sarabia, Jesús; Pérez-Martínez, Cristina; Hernández Del Rincón, Juan Pedro; Luna, Aurelio

2018-05-05

A substantial challenge faced by forensic medicine is determining the postmortem interval (PMI) of skeletonized remains. Currently, the luminol method is of limited forensic usefulness, since it uses qualitative and subjective methods to estimate PMI by the naked eye assessing the degree of chemiluminescence (CL) emitted by bone remains, a technique which is not sensitive enough to distinguish between historical or forensically significant time intervals. The aim of the present study was to use a direct and accurate measurement of the CL by luminol technique in relative light units (RLU) using a luminometer to establish this method as a possible complementary and low cost tool for the determination of the PMI for distinguishing between remains of medical-legal (<20 years) and historical (≥20 years) interest in 102 femur remains with a range of PMI between 15 and 64 years. The results suggest that, under favorable conditions, the luminol technique can detect haemoglobin in the bone in a PMI range of 0-65 years, finding significant differences in the CL intensity among samples with PMI < 20 years and PMI ≥ 20 years. In addition, the intensities of CL measured at 10 s, 15 s and 20 s after reaction with luminol show a statistically significant inverse relationship with PMI in the bone studied, following a decreasing logarithmic model. The conclusion is that this quantitative, objective and contrastable technique could be very useful for determining the PMI in bone remains, since it allows a good degree of precision and eliminates the subjectivity introduced by qualitative techniques. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of postmortem time interval on in vitro culture potential of goat skin tissues stored at room temperature.

PubMed

Singh, Mahipal; Ma, Xiaoling; Sharma, Anil

2012-09-01

Animal cloning using somatic cell nuclear transfer technology has renewed the interest in postmortem tissue storage, since these tissues can be used to reintroduce the lost genes back into the breeding pool in animal agriculture, preserve the genetic diversity, and revive the endangered species. However, for successful cloning of animals, integrity of nuclear DNA is essential. Cell viability and their potential to in vitro culture ensure nuclear integrity. The aim of this study was to determine the limits of postmortem time interval within which live cells can be recovered from goat skin tissues. To test the postmortem tissue storage limits, we cultured 2-3 mm(2) skin pieces (n = 70) from the ears of three breeds of goats (n = 7) after 0, 2, 4, and 6 days of postmortem storage at 24°C. After 10 days of culture, outgrowth of fibroblast-like cells (>50 cells) around the explants was scored. All the explants irrespective of breed displayed outgrowth of cells on the dish containing fresh tissues (i.e., day 0 of storage). However, the number of explants exhibiting outgrowth reduced with increasing time interval. Only 53.85 % explants displayed outgrowth after 2 days of tissue storage. The number of explants displaying outgrowth was much smaller after 4 (16.67 %) and 6 days (13.3 %) of storage. In general, the number of outgrowing cells per explant, on a given day, also decreased with increasing postmortem storage time interval. To test the differences between cell cultures, we established secondary cultures from one of the goats exhibiting outgrowth of cells after 6 days of tissue storage and compared them to similar cells from fresh tissues. Comparison of both the cell lines revealed similar cell morphology and growth curves and had doubling times of 23.04 and 22.56 h, respectively. These results suggest that live cells can be recovered from goat (and perhaps other animal) tissues stored at room temperature even after 6 days of their death with comparable growth profiles and, thus, can be used for tissue banking for preservation of superior genetics, genetic diversity, and cloning of animals.

Permutation Tests of Hierarchical Cluster Analyses of Carrion Communities and Their Potential Use in Forensic Entomology.

PubMed

van der Ham, Joris L

2016-05-19

Forensic entomologists can use carrion communities' ecological succession data to estimate the postmortem interval (PMI). Permutation tests of hierarchical cluster analyses of these data provide a conceptual method to estimate part of the PMI, the post-colonization interval (post-CI). This multivariate approach produces a baseline of statistically distinct clusters that reflect changes in the carrion community composition during the decomposition process. Carrion community samples of unknown post-CIs are compared with these baseline clusters to estimate the post-CI. In this short communication, I use data from previously published studies to demonstrate the conceptual feasibility of this multivariate approach. Analyses of these data produce series of significantly distinct clusters, which represent carrion communities during 1- to 20-day periods of the decomposition process. For 33 carrion community samples, collected over an 11-day period, this approach correctly estimated the post-CI within an average range of 3.1 days. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Effects of intrauterine retention and postmortem interval on body weight following intrauterine death: implications for assessment of fetal growth restriction at autopsy.

PubMed

Man, J; Hutchinson, J C; Ashworth, M; Heazell, A E; Levine, S; Sebire, N J

2016-11-01

According to the classification system used, 15-60% of stillbirths remain unexplained, despite undergoing recommended autopsy examination, with variable attribution of fetal growth restriction (FGR) as a cause of death. Distinguishing small-for-gestational age (SGA) from pathological FGR is a challenge at postmortem examination. This study uses data from a large, well-characterized series of intrauterine death autopsies to investigate the effects of secondary changes such as fetal maceration, intrauterine retention and postmortem interval on body weight. Autopsy findings from intrauterine death investigations (2005-2013 inclusive, from Great Ormond Street Hospital and St George's Hospital, London) were collated into a research database. Growth charts published by the World Health Organization were used to determine normal expected weight centiles for fetuses born ≥ 24 weeks' gestation, and the effects of intrauterine retention (maceration) and postmortem interval were calculated. There were 1064 intrauterine deaths, including 533 stillbirths ≥ 24 weeks' gestation with a recorded birth weight. Of these, 192 (36%) had an unadjusted birth weight below the 10 th centile and were defined as SGA. The majority (86%) of stillborn SGA fetuses demonstrated some degree of maceration, indicating a significant period of intrauterine retention after death. A significantly greater proportion of macerated fetuses were present in the SGA population compared with the non-SGA population (P = 0.01). There was a significant relationship between increasing intrauterine retention interval and both more severe maceration and reduction in birth weight (P < 0.0001 for both), with an average artifactual reduction in birth weight of around -0.8 SD of expected weight. There was an average 12% reduction in fetal weight between delivery and autopsy and, as postmortem interval increased, fetal weight loss increased (P = 0.0001). Based on birth weight alone, 36% of stillbirths are classified as SGA. However, fetuses lose weight in utero with increasing intrauterine retention and continue to lose weight between delivery and autopsy, resulting in erroneous overestimation of FGR. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

[Advances of forensic entomology in China].

PubMed

Lan, Ling-mei; Liao, Zhi-gang; Chen, Yao-qing; Yao, Yue; Li, Jian-bo; Li, Mao-yang; Cai, Ji-feng

2006-12-01

Forensic entomology is a branch of forensic medicine, which applies studies of insects and arthropods to getting evidence for court and has an analogous advantage in the estimation of the postmortem interval (PMI) and other questions of forensic relevance. The paper expounds its definition and contents and reviews some progress of the studies in some aspects in China such as the constitution and succession of insect community on the different cadavers, the applications of morphological features of insects and the technology of analysis of deoxyribonucleic acid (DNA) in forensic entomology, and forensic entomological toxicology etc.

Gene expression during blow fly development: improving the precision of age estimates in forensic entomology.

PubMed

Tarone, Aaron M; Foran, David R

2011-01-01

Forensic entomologists use size and developmental stage to estimate blow fly age, and from those, a postmortem interval. Since such estimates are generally accurate but often lack precision, particularly in the older developmental stages, alternative aging methods would be advantageous. Presented here is a means of incorporating developmentally regulated gene expression levels into traditional stage and size data, with a goal of more precisely estimating developmental age of immature Lucilia sericata. Generalized additive models of development showed improved statistical support compared to models that did not include gene expression data, resulting in an increase in estimate precision, especially for postfeeding third instars and pupae. The models were then used to make blind estimates of development for 86 immature L. sericata raised on rat carcasses. Overall, inclusion of gene expression data resulted in increased precision in aging blow flies. © 2010 American Academy of Forensic Sciences.

Determination of adenosine phosphates in rat gastrocnemius at various postmortem intervals using high performance liquid chromatography.

PubMed

Huang, Hong; Yan, Youyi; Zuo, Zhong; Yang, Lin; Li, Bin; Song, Yu; Liao, Linchuan

2010-09-01

Although the change in adenosine phosphate levels in muscles may contribute to the development of rigor mortis, the relationship between their levels and the onset and development of rigor mortis has not been well elucidated. In the current study, levels of the adenosine phosphates including adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) in gastrocnemius at various postmortem intervals of 180 rats from different death modes were detected by high performance liquid chromatography. The results showed that the levels of ATP and ADP significantly decreased along with the postmortem period of rats from different death mode whereas the AMP level remained the same. In addition, it was found that changes in the ATP levels in muscles after death correlated well with the development of rigor mortis. Therefore, the ATP level could serve as a reference parameter for the deduction of rigor mortis in forensic science.

Pericardial fluid is suitable as an alternative specimen for the measurement of β-hydroxybutyrate within 96 h after death.

PubMed

Mizutani, Tatsushi; Yoshimoto, Takashi; Ishii, Akira

2018-05-21

We examined postmortem β-hydroxybutyrate (BHB) levels in the body fluids obtained from 253 forensic autopsy cases whose causes of death were determined. Postmortem changes of BHB levels according to postmortem intervals (PMI) in various body fluids (plasma, urine, vitreous humor, and pericardial fluids) were investigated to determine appropriate alternative specimens as plasma samples. Our study has indicated the following points: 1) the BHB levels in plasma specimens from three sampling sites showed no significant differences, 2) postmortem changes of BHB levels in plasma and pericardial fluids could be negligible within 96 h PMI, while urine and vitreous humor BHB levels showed postmortem changes, and 3) pericardial fluid would thus be most suitable as an alternative to plasma in postmortem BHB level. We have also proposed that BHB levels could be applicable for the diagnosis of metabolic disorders in forensic autopsy. Copyright © 2018 Elsevier B.V. All rights reserved.

Temperature measurement from the brain and rectum in charred corpses: a pilot study on an animal model.

PubMed

Gibelli, Daniele; Cantatore, Angela; Porta, Davide; Poppa, Pasquale; Sala, Remo; Marco, Grandi; Cattaneo, Cristina

2014-03-01

Measurement of body temperature provides relevant data on postmortem interval, and different studies have been so far attempted to apply temperature assessment methods also under extreme environmental conditions; however, none of them has been performed yet on charred or heated bodies, where temperature measurement is presumed to be unreliable because of the possible influence of heating. This study aimed at verifying any possible early-stage alterations of rectal and endocranial temperature due to fire on an animal model during the charring process. Three pigs, 2 adults (pigs 1 and 2) whose weight was about 50 kg each and 1 piglet weighing 3 kg, were heated and burnt on a natural fire lit on top of a wooden stack, without the use of accelerants; 2 thermocouples were positioned in the rectum and in the cranium to record second-by-second rectal and endocranial temperature values. Results demonstrate that the rectal temperature does not seem to increase in adult pigs for 40 to 50 minutes after the body has been exposed to fire, probably because of the thermal insulating characteristics of the adipose tissue. Therefore, temperature may still be of some help for estimating postmortem interval on heated or burnt cadavers.

Evaluation of hypostasis using a colorimeter measuring system and its application to assessment of the post-mortem interval (time of death).

PubMed

Vanezis, P; Trujillo, O

1996-03-05

Hypostasis was measured in 93 cadavers using a tristimulus colorimeter in order to investigate its relationship with the time of death. The intensity (lightness) of the hypostasis in each case was measured over a period of 4 h and the rate of change in lightness derived. When examined against the time of death, it was found that there was a good correlation between the two. Namely, that the rate of change of lightness (and it can be inferred that this represents displaceability) decreases as the post-mortem period increases. The shift in hypostasis was particularly marked in the first 12 h and decreased thereafter. However, hypostasis could be useful for time of death estimation for up to 48 h. After this time, the degree of change was small or non-existent and by 72 h hypostasis had become fixed in the majority of cases, within our measuring period of 4 h.

Caution! All data are not created equal: The hazards of using National Weather Service data for calculating accumulated degree days.

PubMed

Dabbs, Gretchen R

2010-10-10

An increasing number of anthropological decomposition studies are utilizing accumulated degree days (ADD) to quantify and estimate the post-mortem interval (PMI) at given decompositional stages, or the number of ADD required for certain events, such as tooth exfoliation, to occur. This study addresses the utility of retroactively applying temperature data from the closest National Weather Service (NWS) station to these calculations as prescribed in the past. Hourly temperature readings were collected for 154 days at a research site in Farmington, AR between June 30 and December 25, 2008. These were converted to average daily temperatures by calculating the mean of the 24 hourly values, following the NWS reporting procedure. These data were compared to comparable data from the Owl Creek and Drake Field NWS stations, the two closest to the research site, located 5.7 and 9.9km away, respectively. Paired samples t-tests between the research site and each of the NWS stations show significant differences between the average daily temperature data collected at the research station, and both Owl Creek (2.0°C, p<0.001) and Drake Field (0.6°C, p<0.001). When applied to a simulated recovery effort, the further NWS station also proved to represent the better model for the recovery site. Using a published equation for estimating post-mortem interval using ADD and total body decomposition scores (Megyesi et al., 2005 [1]), the Drake Field data produced estimates of PMI more closely mirroring those of the research site than did Owl Creek. This demonstrates that instead of automatically choosing the nearest NWS station, care must be taken when choosing an NWS station for retroactively gathering temperature data for application of PMI estimation techniques using accumulated degree days to ensure the station adequately reflects temperature conditions at the recovery site. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Association of Postmortem Blood Hemoglobin A1c Levels With Diabetic Conditions in Aviation Accident Pilot Fatalities

DTIC Science & Technology

2001-07-01

A1c ( HbA1c ) at selected time intervals during the 52-day period. Postmortem blood specimens from 34 aviation accident pilot fatalities were also...analyzed. Some of these pilots had a known history of diabetes. Results. HbA1c values in blood from volunteers did not significantly change for up to 52...days. The HbA1c concentration in postmortem blood samples from pilots ranged from 3.9-10.5%. Only one pilot with a HbA1c over 6.0% did not have a

Comparison of the post-mortem interval on the effect of vascular responses to the activation of ionotropic and metabotropic receptors.

PubMed

Bloch-Bogusławska, Elżbieta; Grześk, Elżbieta; Grześk, Grzegorz

2015-03-01

The contractibility of blood vessels depends on their normal structure and the availability of calcium ions; it changes under the influence of numerous contracting and relaxing factors, which control the activities of various pathways of intracellular and intercellular signaling. The main aim of the study was to investigate, by means of perfusion pressure in rat tail arteries, the role of Ca 2+ in vascular response to α-1 adrenoceptor activation by phenylephrine (PHE) and Bay K8644 agonist of the L-type calcium channel and caffeine before and after a post-mortem interval (PMI) of 2, 4, 6 and 8 h. A phasic increase of perfusion pressure in rat tail arteries, as induced by PHE or caffeine, in Ca 2+ -free solutions was used as an indicator of intracellular Ca 2+ release through the inositol 1,4,5-triphosphate and ryanodine receptor pathways, respectively. In Ca 2+ -free-ethylene glycol tetraacetic acid (EGTA)-poly(sodium styrenesulfonate) (PSS) and in Ca 2+ -EGTA-PSS, the PHE induced elevation of perfusion pressure significantly decreased. Vascular responses to caffeine (20 mmol/1) in Ca 2+ -free-EGTA-PSS, with an increase of PMI from 2-8 h, did not change significantly. A similar effect was observed with vascular responses to KCl 40 mmol/1 in Ca 2+ -EGTA-PSS. To confirm whether the inhibitory effect of 2, 4, 6 and 8 h PMI was mediated through the formation of NO, nitro-L-arginine (L-NNA), a potent NO synthase inhibitor, was used. Exposure to L-NNA (10 -5 M) blocked the inhibition induced by an increase of PMI. The blocked effects of L-NNA were reversed by L-arginine (10 -4 M). In conclusion, these patterns of change in artery responses provide insight into the post-mortem change in the receptor-mediated signaling components in epithelial and smooth muscle cells, and support the further study of post-mortem vascular responses triggered by G protein-coupled receptors (metabotropic) and channel-linked receptors (ionotropic) as potential markers for estimating short and long-term PMIs, respectively.

Postmortem changes in the neuroanatomical characteristics of the primate brain: the hippocampal formation

PubMed Central

Lavenex, Pierre; Lavenex, Pamela Banta; Bennett, Jeffrey L.; Amaral, David G.

2009-01-01

Comparative studies of the structural organization of the brain are fundamental to our understanding of human brain function. However, whereas brains of experimental animals are fixed by perfusion of a fixative through the vasculature, human or ape brains are fixed by immersion after varying postmortem intervals. Although differential treatments might affect the fundamental characteristics of the tissue, this question has not been evaluated empirically in primate brains. Monkey brains were either perfused, or acquired after varying postmortem intervals before immersion-fixation in 4% paraformaldehyde. We found that the fixation method affected the neuroanatomical characteristics of the monkey hippocampal formation. Soma size was smaller in Nissl-stained, immersion-fixed tissue, although overall brain volume was larger, as compared to perfusion-fixed tissue. Non-phosphorylated high-molecular-weight neurofilament immunoreactivity was lower in CA3 pyramidal neurons, dentate mossy cells and the entorhinal cortex, whereas it was higher in the mossy fiber pathway in immersion-fixed tissue. Serotonin-immunoreactive fibers were well-stained in perfused tissue but were undetectable in immersion-fixed tissue. Although regional immunoreactivity patterns for calcium-binding proteins were not affected, intracellular staining degraded with increasing postmortem intervals. Somatostatin-immunoreactive clusters of large axonal varicosities, previously reported only in humans, were observed in immersion-fixed monkey tissue. In addition, calretinin-immunoreactive multipolar neurons, previously observed only in rodents, were found in the rostral dentate gyrus in both perfused and immersion-fixed brains. In conclusion, comparative studies of the brain must evaluate the effects of fixation on the staining pattern of each marker in every structure of interest before drawing conclusions about species differences. PMID:18972553

Postmortem changes in the neuroanatomical characteristics of the primate brain: hippocampal formation.

PubMed

Lavenex, Pierre; Lavenex, Pamela Banta; Bennett, Jeffrey L; Amaral, David G

2009-01-01

Comparative studies of the structural organization of the brain are fundamental to our understanding of human brain function. However, whereas brains of experimental animals are fixed by perfusion of a fixative through the vasculature, human or ape brains are fixed by immersion after varying postmortem intervals. Although differential treatments might affect the fundamental characteristics of the tissue, this question has not been evaluated empirically in primate brains. Monkey brains were either perfused or acquired after varying postmortem intervals before immersion-fixation in 4% paraformaldehyde. We found that the fixation method affected the neuroanatomical characteristics of the monkey hippocampal formation. Soma size was smaller in Nissl-stained, immersion-fixed tissue, although overall brain volume was larger as compared to perfusion-fixed tissue. Nonphosphorylated high-molecular-weight neurofilament immunoreactivity was lower in CA3 pyramidal neurons, dentate mossy cells, and the entorhinal cortex, whereas it was higher in the mossy fiber pathway in immersion-fixed tissue. Serotonin-immunoreactive fibers were well stained in perfused tissue but were undetectable in immersion-fixed tissue. Although regional immunoreactivity patterns for calcium-binding proteins were not affected, intracellular staining degraded with increasing postmortem intervals. Somatostatin-immunoreactive clusters of large axonal varicosities, previously reported only in humans, were observed in immersion-fixed monkey tissue. In addition, calretinin-immunoreactive multipolar neurons, previously observed only in rodents, were found in the rostral dentate gyrus in both perfused and immersion-fixed brains. In conclusion, comparative studies of the brain must evaluate the effects of fixation on the staining pattern of each marker in every structure of interest before drawing conclusions about species differences.

Citrate Content of Bone as a Measure of Postmortem Interval: An External Validation Study.

PubMed

Brown, Michael A; Bunch, Ann W; Froome, Charles; Gerling, Rebecca; Hennessy, Shawn; Ellison, Jeffrey

2017-12-26

The postmortem interval (PMI) of skeletal remains is a crucial piece of information that can help establish the time dimension in criminal cases. Unfortunately, the accurate and reliable determination of PMI from bone continues to evade forensic investigators despite concerted efforts over the past decades to develop suitable qualitative and quantitative methods. A relatively new PMI method based on the analysis of citrate content of bone was developed by Schwarcz et al. The main objective of our research was to determine whether this work could be externally validated. Thirty-one bone samples were obtained from the Forensic Anthropology Center, University of Tennessee, Knoxville, and the Onondaga County Medical Examiner's Office. Results from analyzing samples with PMI greater than 2 years suggest that the hypothetical relationship between the citrate content of bone and PMI is much weaker than reported. It was also observed that the average absolute error between the PMI value estimated using the equation proposed by Schwarcz et al. and the actual ("true") PMI of the sample was negative indicating an underestimation in PMI. These findings are identical to those reported by Kanz et al. Despite these results this method may still serve as a technique to sort ancient from more recent skeletal cases, after further, similar validation studies have been conducted. © 2017 American Academy of Forensic Sciences.

Postmortem Brain: An Underutilized Substrate for Studying Severe Mental Illness

PubMed Central

McCullumsmith, Robert E; Hammond, John H; Shan, Dan; Meador-Woodruff, James H

2014-01-01

We propose that postmortem tissue is an underutilized substrate that may be used to translate genetic and/or preclinical studies, particularly for neuropsychiatric illnesses with complex etiologies. Postmortem brain tissues from subjects with schizophrenia have been extensively studied, and thus serve as a useful vehicle for illustrating the challenges associated with this biological substrate. Schizophrenia is likely caused by a combination of genetic risk and environmental factors that combine to create a disease phenotype that is typically not apparent until late adolescence. The complexity of this illness creates challenges for hypothesis testing aimed at understanding the pathophysiology of the illness, as postmortem brain tissues collected from individuals with schizophrenia reflect neuroplastic changes from a lifetime of severe mental illness, as well as treatment with antipsychotic medications. While there are significant challenges with studying postmortem brain, such as the postmortem interval, it confers a translational element that is difficult to recapitulate in animal models. On the other hand, data derived from animal models typically provide specific mechanistic and behavioral measures that cannot be generated using human subjects. Convergence of these two approaches has led to important insights for understanding molecular deficits and their causes in this illness. In this review, we discuss the problem of schizophrenia, review the common challenges related to postmortem studies, discuss the application of biochemical approaches to this substrate, and present examples of postmortem schizophrenia studies that illustrate the role of the postmortem approach for generating important new leads for understanding the pathophysiology of severe mental illness. PMID:24091486

[Relationship between Electrical Conductivity and Decomposition Rate of Rat Postmortem Skeletal Muscle].

PubMed

Xia, Z Y; Zhai, X D; Liu, B B; Zheng, Z; Zhao, L L; Mo, Y N

2017-02-01

To analyze the relationship among electrical conductivity （EC）, total volatile basic nitrogen （TVB-N）, which is an index of decomposition rate for meat production, and postmortem interval （PMI）. To explore the feasibility of EC as an index of cadaveric skeletal muscle decomposition rate and lay the foundation for PMI estimation. Healthy Sprague-Dawley rats were sacrificed by cervical vertebrae dislocation and kept at 28 ℃. Muscle of rear limbs was removed at different PMI, homogenized in deionized water and then skeletal extraction liquid of mass concentration 0.1 g/mL was prepared. EC and TVB-N of extraction liquid were separately determined. The correlation between EC ( x ₁) and TVB-N ( x ₂) was analyzed, and their regression function was established. The relationship between PMI ( y ) and these two parameters were studied, and their regression functions were separately established. The change trends of EC and TVB-N of skeletal extraction liquid at different PMI were almost the same, and there was a linear positive correlation between them. The regression equation was x ₂=0.14 x ₁-164.91( R ²=0.982). EC and TVB-N of skeletal muscle changed significantly with PMI, and the regression functions were y =19.38 x ₁³-370.68 x ₁²+2 526.03 x ₁-717.06( R ²=0.994), and y =2.56 x ₂³-48.39 x ₂²+330.60 x ₂-255.04( R ²=0.997), respectively. EC and TVB-N of rat postmortem skeletal muscle show similar change trends, which can be used as an index for decomposition rate of cadaveric skeletal muscle and provide a method for further study of late PMI estimation. Copyright© by the Editorial Department of Journal of Forensic Medicine

The Elusive Universal Post-Mortem Interval Formula

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vass, Arpad Alexander

The following manuscript details our initial attempt at developing universal post-mortem interval formulas describing human decomposition. These formulas are empirically derived from data collected over the last 20 years from the University of Tennessee's Anthropology Research Facility, in Knoxville, Tennessee, USA. Two formulas were developed (surface decomposition and burial decomposition) based on temperature, moisture, and the partial pressure of oxygen, as being three of the four primary drivers for human decomposition. It is hoped that worldwide application of these formulas to environments and situations not readily studied in Tennessee will result in interdisciplinary cooperation between scientists and law enforcement personnelmore » that will allow for future refinements of these models leading to increased accuracy.« less

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

PubMed

Fleischer, Luise; Sehner, Susanne; Gehl, Axel; Riemer, Martin; Raupach, Tobias; Anders, Sven

2017-05-01

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. © 2016 American Academy of Forensic Sciences.

Gastrointestinal Functionality of Aquatic Animal (Oreochromis niloticus) Carcass in Water Allows Estimating Time of Death.

PubMed

Hahor, Waraporn; Thongprajukaew, Karun; Yoonram, Krueawan; Rodjaroen, Somrak

2016-11-01

Postmortem changes have been previously studied in some terrestrial animal models, but no prior information is available on aquatic species. Gastrointestinal functionality was investigated in terms of indices, protein concentration, digestive enzyme activity, and scavenging activity, in an aquatic animal model, Nile tilapia, to assess the postmortem changes. Dead fish were floated indoors, and samples were collected within 48 h after death. Stomasomatic index decreased with postmortem time and correlated positively with protein, pepsin-specific activity, and stomach scavenging activity. Also intestosomatic index decreased significantly and correlated positively with protein, specific activity of trypsin, chymotrypsin, amylase, lipase, and intestinal scavenging activity. In their postmortem changes, the digestive enzymes exhibited earlier lipid degradation than carbohydrate or protein. The intestine changed more rapidly than the stomach. The findings suggest that the postmortem changes of gastrointestinal functionality can serve as primary data for the estimation of time of death of an aquatic animal. © 2016 American Academy of Forensic Sciences.

Study of insect succession and rate of decomposition on a partially burned pig carcass in an oil palm plantation in Malaysia.

PubMed

Heo, Chong Chin; Mohamad, Abdullah Marwi; Ahmad, Firdaus Mohd Salleh; Jeffery, John; Kurahashi, Hiromu; Omar, Baharudin

2008-12-01

Insects found associated with corpse can be used as one of the indicators in estimating postmortem interval (PMI). The objective of this study was to compare the stages of decomposition and faunal succession between a partially burnt pig (Sus scrofa Linnaeus) and natural pig (as control). The burning simulated a real crime whereby the victim was burnt by murderer. Two young pigs weighed approximately 10 kg were used in this study. Both pigs died from pneumonia and immediately placed in an oil palm plantation near a pig farm in Tanjung Sepat, Selangor, Malaysia. One pig was partially burnt by 1-liter petrol while the other served as control. Both carcasses were visited twice per day for the first week and once thereafter. Adult flies and larvae on the carcasses were collected and later processed in a forensic entomology laboratory. Results showed that there was no significant difference between the rate of decomposition and sequence of faunal succession on both pig carcasses. Both carcasses were completely decomposed to remain stage after nine days. The species of flies visiting the pig carcasses consisted of blow flies (Chrysomya megacephala, Chrysomya rufifacies, Hemipyrellia ligurriens), flesh fly (Sarcophagidae.), muscid fly (Ophyra spinigera), soldier fly (Hermetia illucens), coffin fly (Phoridae) and scavenger fly (Sepsidae). The only difference noted was in the number of adult flies, whereby more flies were seen in the control carcass. Faunal succession on both pig carcasses was in the following sequence: Calliphoridae, Sarcophagidae, Muscidae, Phoridae and lastly Stratiomyidae. However, there was overlap in the appearance of members of these families. Blowflies continued to oviposit on both carcasses. Hence postmortem interval (PMI) can still be estimated from the partially burnt pig carcass.

Microbial communities associated with human decomposition and their potential use as postmortem clocks.

PubMed

Finley, Sheree J; Benbow, M Eric; Javan, Gulnaz T

2015-05-01

Most forensic research that is used to better understand how to estimate the postmortem interval (PMI) entails the study of the physiochemical characteristics of decomposition and the effects that environmental factors have on the decomposition process. Forensic entomology exploits the life cycles of arthropods like Diptera (blow flies or flesh flies) and Coleoptera (beetles) deposited on the decaying carcass to determine PMI. Forensic taphonomy, from the Greek word taphos meaning burial, studies the creation of the fossils of decomposed cadavers to ascertain information as to the nature and time of death. Compared to other areas of taphonomy, there have been relatively few forensic science studies that have investigated the impact of human decomposition on the microbial changes occurring on or in a corpse or in the soil communities underneath a body. Such research may facilitate the critical determination of PMI. Therefore, the scope of this review is to provide a concise summary of the current progress in the newly emerging field of microbial diversity and the next-generation metagenomic sequencing approaches for assessing these communities in humans and in the soil beneath decomposing human.

Expansion of Microbial Forensics

PubMed Central

Schmedes, Sarah E.; Sajantila, Antti

2016-01-01

Microbial forensics has been defined as the discipline of applying scientific methods to the analysis of evidence related to bioterrorism, biocrimes, hoaxes, or the accidental release of a biological agent or toxin for attribution purposes. Over the past 15 years, technology, particularly massively parallel sequencing, and bioinformatics advances now allow the characterization of microorganisms for a variety of human forensic applications, such as human identification, body fluid characterization, postmortem interval estimation, and biocrimes involving tracking of infectious agents. Thus, microbial forensics should be more broadly described as the discipline of applying scientific methods to the analysis of microbial evidence in criminal and civil cases for investigative purposes. PMID:26912746

Microbiome Tools for Forensic Science.

PubMed

Metcalf, Jessica L; Xu, Zhenjiang Z; Bouslimani, Amina; Dorrestein, Pieter; Carter, David O; Knight, Rob

2017-09-01

Microbes are present at every crime scene and have been used as physical evidence for over a century. Advances in DNA sequencing and computational approaches have led to recent breakthroughs in the use of microbiome approaches for forensic science, particularly in the areas of estimating postmortem intervals (PMIs), locating clandestine graves, and obtaining soil and skin trace evidence. Low-cost, high-throughput technologies allow us to accumulate molecular data quickly and to apply sophisticated machine-learning algorithms, building generalizable predictive models that will be useful in the criminal justice system. In particular, integrating microbiome and metabolomic data has excellent potential to advance microbial forensics. Copyright © 2017. Published by Elsevier Ltd.

Identification of Forensically Important Calliphoridae and Sarcophagidae Species Collected in Korea Using SNaPshot Multiplex System Targeting the Cytochrome c Oxidase Subunit I Gene

PubMed Central

Park, Ji Hye

2018-01-01

Estimation of postmortem interval (PMI) is paramount in modern forensic investigation. After the disappearance of the early postmortem phenomena conventionally used to estimate PMI, entomologic evidence provides important indicators for PMI estimation. The age of the oldest fly larvae or pupae can be estimated to pinpoint the time of oviposition, which is considered the minimum PMI (PMImin). The development rate of insects is usually temperature dependent and species specific. Therefore, species identification is mandatory for PMImin estimation using entomological evidence. The classical morphological identification method cannot be applied when specimens are damaged or have not yet matured. To overcome this limitation, some investigators employ molecular identification using mitochondrial cytochrome c oxidase subunit I (COI) nucleotide sequences. The molecular identification method commonly uses Sanger's nucleotide sequencing and molecular phylogeny, which are complex and time consuming and constitute another obstacle for forensic investigators. In this study, instead of using conventional Sanger's nucleotide sequencing, single-nucleotide polymorphisms (SNPs) in the COI gene region, which are unique between fly species, were selected and targeted for single-base extension (SBE) technology. These SNPs were genotyped using a SNaPshot® kit. Eleven Calliphoridae and seven Sarcophagidae species were covered. To validate this genotyping, fly DNA samples (103 adults, 84 larvae, and 4 pupae) previously confirmed by DNA barcoding were used. This method worked quickly with minimal DNA, providing a potential alternative to conventional DNA barcoding. Consisting of only a few simple electropherogram peaks, the results were more straightforward compared with those of the conventional DNA barcoding produced by Sanger's nucleotide sequencing. PMID:29682531

Effect of morphine on the growth rate of Calliphora stygia (Fabricius) (Diptera: Calliphoridae) and possible implications for forensic entomology.

PubMed

George, Kelly A; Archer, Melanie S; Green, Lauren M; Conlan, Xavier A; Toop, Tes

2009-12-15

Insect specimens collected from decomposing bodies enable forensic entomologists to estimate the minimum post-mortem interval (PMI). Drugs and toxins within a corpse may affect the development rate of insects that feed on them and it is vital to quantify these effects to accurately calculate minimum PMI. This study investigated the effects of morphine on growth rates of the native Australian blowfly, Calliphora stygia (Fabricius) (Diptera: Calliphoridae). Several morphine concentrations were incorporated into pet mince to simulate post-mortem concentrations in morphine, codeine and/or heroin-dosed corpses. There were four treatments for feeding larvae; T 1: control (no morphine); T 2: 2 microg/g morphine; T 3: 10 microg/g morphine; and T 4: 20 microg/g morphine. Ten replicates of 50 larvae were grown at 22 degrees C for each treatment and their development was compared at four comparison intervals; CI 1: 4-day-old larvae; CI 2: 7-day-old larvae; CI 3: pupae; and CI 4: adults. Length and width were measured for larvae and pupae, and costae and tibiae were measured for adults. Additionally, day of pupariation, day of adult eclosion, and survivorship were calculated for each replicate. The continued presence of morphine in meat was qualitatively verified using high-performance liquid chromatography with acidic potassium permanganate chemiluminescence detection. Growth rates of C. stygia fed on morphine-spiked mince did not differ significantly from those fed on control mince for any comparison interval or parameter measured. This suggests that C. stygia is a reliable model to use to accurately age a corpse containing morphine at any of the concentrations investigated.

Effect of antemortem and postmortem factors on ( sup 3 H)MK-801 binding in the human brain: Transient elevation during early childhood

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kornhuber, J.; Mack-Burkhardt, F.; Konradi, C.

1989-01-01

The effect of a number of antemortem and postmortem factors on ({sup 3}H)MK-801 binding was investigated under equilibrium conditions in the frontal cortex of human brains of 38 controls. Binding values transiently increased during the early postnatal period reaching a maximum at the age of about 2 years. After age 10 years ({sup 3}H)MK-801 binding sites disappeared at 5.7% per decade. The storage time of brain tissue had a reducing effect on these binding sites. There was no effect of gender, brain weight or postmortem time interval and the binding sites were bilaterally symmetrically distributed in the frontal cortex.

[Contents of vitreous humor of dead body with different postmortem intervals].

PubMed

Tao, Tao; Xu, Jing; Luo, Tong-Xing; Liao, Zhi-Gang; Pan, Hong-Fu

2006-11-01

To establish regression correlations between postmortem interval (PMI) and contents of human vitreous humor of dead bodies for forensic purposes. The human vitreous humor were taken from 126 dead bodies between 0.5 to 216 hours after death, and 11 chemical elements were detected by the OLYMPUS AU400 auto-biochemistry instrument. (1) The glucose, natrium and chlorine in human vitreous humor decreased, while the urea, creatinine, uric acid, potassium, calcium, magnesium, phosphorus, and micro-protein increased after death. The change of glucose, potassium and phosphorus were well correlated with the PMI (r = 0.824, 0.967, 0.880). But the uric acid and micro-protein did not have a good correlation with the PMI(r = 0.350, 0.153). (2) The stepwise regression analysis established the following equations for the PMI (Y): Y = -35. 15+6.05X, R2 = 0.957 (X = potassium); Y = -27.83+ 5.49X(1) - 1.35X(2), R2 = 0.960 (X(1) = potassium, X(2) = glucose); Y = -6.37+3.93X(1) -2.29X(2) + 5.36X(3), R2 = 0.966 (X(1) = potassium, X(2) = glucose, X(3) = phosphorus). (1) Eleven chemical components in human vitreous humor change after death, among which postassium has the best linear correlation with the PMI within 72 hours after death. (2) The accuracy of the estimation of PMI could be improved by establishing a multi-variable equation through stepwise regression.

Plastic waste sacks alter the rate of decomposition of dismembered bodies within.

PubMed

Scholl, Kassra; Moffatt, Colin

2017-07-01

As a result of criminal activity, human bodies are sometimes dismembered and concealed within sealed, plastic waste sacks. Consequently, due to the inhibited ingress of insects and dismemberment, the rate of decomposition of the body parts within may be different to that of whole, exposed bodies. Correspondingly, once found, an estimation of the postmortem interval may be affected and lead to erroneous inferences. This study set out to determine whether insects were excluded and how rate of decomposition was affected inside such plastic sacks. The limbs, torsos and heads of 24 dismembered pigs were sealed using nylon cable ties within plastic garbage sacks, half of which were of a type claimed to repel insects. Using a body scoring scale to quantify decomposition, the body parts in the sacks were compared to those of ten exposed, whole pig carcasses. Insects were found to have entered both types of plastic sack. There was no difference in rate of decomposition in the two types of sack (F 1,65  = 1.78, p = 0.19), but this was considerably slower than those of whole carcasses (F 1,408  = 1453, p < 0.001), with heads showing the largest differences. As well as a slower decomposition, sacks resulted in formation of some adipocere tissue as a result of high humidity within. Based upon existing methods, postmortem intervals for body parts within sealed sacks would be significantly underestimated.

Blood creatinine level in postmortem cases.

PubMed

Nishida, Atsushi; Funaki, Hironao; Kobayashi, Masaki; Tanaka, Yuka; Akasaka, Yoshihisa; Kubo, Toshikazu; Ikegaya, Hiroshi

2015-05-01

Blood chemical analysis for the diagnosis of diseases in forensic cases should be conducted in the same way as for clinical cases. However, it is sometimes difficult to obtain serum samples in forensic cases because of postmortem changes such as hemolysis and putrefaction. This study aimed to evaluate renal function in postmortem cases by blood creatinine analysis. The blood creatinine level was measured by high performance liquid chromatography (HPLC) using whole blood samples taken from 77 postmortem cases, and the relationships between blood creatinine level, postmortem interval, and cause of death were examined. The median blood creatinine level was found to be 1.15 mg/dL, with no significant differences between blood samples taken from different parts of the body. The blood creatinine level was stable for 3 days after death and gradually increased after that period, in line with a previous study using enzymatic analysis that found the serum creatinine level was stable in the early postmortem period. The blood creatinine level was high in the cases of blunt injury, intoxication, and in deaths caused by fire. This was considered to reflect acute renal dysfunction. However, the postmortem blood creatinine level remained higher than the clinical normal value despite omitting cases with renal dysfunction from the analysis. Therefore, we next investigated the change in postmortem creatinine levels in mice and found that the blood creatinine level increased with the emergence of rigor mortis. Our findings indicate that HPLC is useful in the postmortem evaluation of renal function even in the cases where serum cannot be obtained. However, the presence of rigor mortis should be considered in the evaluation of blood creatinine values. Copyright © 2014 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

A forensic entomology case from the Amazon rain forest of Brazil.

PubMed

Pujol-Luz, José R; Marques, Helder; Ururahy-Rodrigues, Alexandre; Rafael, José Albertino; Santana, Fernando H A; Arantes, Luciano C; Constantino, Reginaldo

2006-09-01

The first case of application of forensic entomology in the Brazilian Amazonia is described. The corpses of 26 men were found in the rainforest in Rondonia State, Brazil. Fly larvae collected on the bodies during autopsy were identified as Paralucilia fulvinota (Diptera, Calliphoridae). No data or specimens were collected at the crime scene. At the laboratory, the larvae developed into pupae in 58 h and into adults in 110.5 h. The total development time for P. fulvinota was measured in field experiments inside the forest. The age of the larvae when collected from the bodies was estimated as the difference between the time required for them to become adults and the total development time for this species. The estimated age of the maggots and the minimum postmortem interval was 5.7 days.

Postmortem bone marrow analysis in forensic science: study of 73 cases and review of the literature.

PubMed

Tattoli, Lucia; Tsokos, Michael; Sautter, Julia; Anagnostopoulos, Joannis; Maselli, Eloisa; Ingravallo, Giuseppe; Delia, Mario; Solarino, Biagio

2014-01-01

In forensic sciences, bone marrow (BM) is an alternative matrix in postmortem toxicology because of its good resistance to autolysis and contaminations. Nevertheless, few studies have been focused on postmortem BM morphological changes after pathological stimuli. We examined 73 BM samples from forensic autopsies; causes of death were both natural and traumatic. BM samples were collected from the sternum by needle aspiration and biopsy; in selected cases, immunohistochemistry was performed. Few autolytic changes were found; BM cellularity decreased with increasing age and postmortem interval. Notable cell changes were detected in 45 cases (61.64%): neoplastic (n=4), and non-neoplastic BM findings (n=41), including multiorgan failure/sepsis (n=26), myelodisplastic-like conditions (n=11), and anaphylactic reactions (n=4). The results showed that BM cellularity supported circumstantial and autopsy findings, suggesting that BM samples could be a useful tool in forensic science applications. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

[Definition of a "domestic-setting corpse"--a retrospective study of 211 discoveries].

PubMed

Merz, Marius; Heidorn, Frank; Birngruber, Christoph G; Ramsthaler, Frank; Risse, Manfred; Kreutz, Kerstin; Krähahn, Jonathan; Verhoff, Marcel A

2012-01-01

In Germany, the term "domestic-setting corpse" is regularly used both in the medicolegal field (daily work, specialist literature) and by the general public (press, novels). The only formal definition of the term is in the German-language textbook "Basiswissen Rechtsmedizin" (Madea and Dettmeyer 2007). In this retrospective study, we compared the criteria for this definition with our findings. Autopsy reports from the Institute of Forensic Medicine at the Justus Liebig University in Giessen, Germany, for the period between 2005 and 2011 (including February), were reviewed retropectively to see if the criteria for this formal definition could be found. We chose a postmortem interval of more than 24 hours and discovery of the corpse in a private home as inclusion criteria for our study (n = 211). We could verify four of the criteria for the definition ("advanced signs of decomposition", "reclusiveness", "unclear cause of death", "difficult to identify") in our study. One criterion ("frequently a long postmortem interval") was too vague to be of use, and two further criteria ("discovery circumstances" and "high frequency of active alcohol dependence") could only be partially confirmed. In almost half of our cases there were, however, signs of general substance abuse. The proportion of male "domestic-setting corpses" was distinctly higher than that of females (approx. 3:1). The average age-at-death was 50.1 years for men, and 57.8 years for women, and thus clearly below the average life expectancies. In over half of the cases - even those with explicitly mentioned advanced facial decay--the identification method had not been noted. In the formal definition, the criteria "discovery circumstances" and "alcoholism" thus need to be more precisely defined. Also, due to the inexplicit time range, the criterion "frequently a long postmortem interval" was too vague to be applied to, or compared with, our cases as a classic criterion. We suggest specifying a minimum postmortem interval of 24 hours for "domestic-setting corpses". In addition, more attention should be paid to the identification of "domestic-setting corpses". To date, investigation authorities frequently seem to assume that a corpse discovered in a private residence is that of the home owner or occupant.

Expansion of Microbial Forensics.

PubMed

Schmedes, Sarah E; Sajantila, Antti; Budowle, Bruce

2016-08-01

Microbial forensics has been defined as the discipline of applying scientific methods to the analysis of evidence related to bioterrorism, biocrimes, hoaxes, or the accidental release of a biological agent or toxin for attribution purposes. Over the past 15 years, technology, particularly massively parallel sequencing, and bioinformatics advances now allow the characterization of microorganisms for a variety of human forensic applications, such as human identification, body fluid characterization, postmortem interval estimation, and biocrimes involving tracking of infectious agents. Thus, microbial forensics should be more broadly described as the discipline of applying scientific methods to the analysis of microbial evidence in criminal and civil cases for investigative purposes. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

The first report of Telomerina flavipes (Meigen, 1830) (Diptera, Sphaeroceridae) in a forensic case, with redescription of its pupa.

PubMed

Arnaldos, María-Isabel; Ubero-Pascal, Nicolás; García, Rafael; Carles-Tolrá, Miguel; Presa, Juan-José; García, María-Dolores

2014-09-01

This paper presents a forensic investigation that took place in the city of Murcia (SE Spain) and shows how the entomological specimens collected at the scene were extremely helpful for estimating the minimum post-mortem interval (PMImin). The occurrence of Telomerina flavipes (Meigen, 1830) (Diptera: Sphaeroceridae) is reported here for the first time in a forensic case. Additionally, the importance of other entomological evidence in this case is discussed. The first known images of the puparium are provided, as well as its redescription and that of the cephalopharyngeal skeleton recovered from the puparium. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The effect of temperature on development of Sarconesia chlorogaster, a blowfly of forensic importance.

PubMed

Lecheta, Melise Cristine; Thyssen, Patricia Jacqueline; Moura, Mauricio Osvaldo

2015-12-01

The blowfly Sarconesia chlorogaster (Diptera: Calliphoridae) is of limited forensic use in South America, due to the poorly known relationship between development time and temperature. The purpose of this study was to determine development time of S. chlorogaster at different constant temperatures, thereby enabling the forensic use of this fly. Development time of this species was examined by observing larval development at six temperatures (10, 15, 20, 25, 30, 35 °C). The thermal constant (K), the minimum development threshold (t 0), and development rate were calculated using linear regressions of the development time interval at five temperatures (10-30 °C). Development interval from egg to adult varied from 14.2 to 95.2 days, depending on temperature. The t0 calculated for total immature development is 6.33 °C and the overall thermal constant is 355.51 degree-days (DD). Temperature affected the viability of pupae, at 35 °C 100 % mortality was observed. Understanding development rate across these temperatures now makes development of S. chlorogaster a forensically useful tool for estimating postmortem interval.

Longitudinal progesterone profiles in baleen from female North Atlantic right whales (Eubalaena glacialis) match known calving history

PubMed Central

Hunt, Kathleen E.; Lysiak, Nadine S.; Moore, Michael J.; Rolland, Rosalind M.

2016-01-01

Reproduction of mysticete whales is difficult to monitor, and basic parameters, such as pregnancy rate and inter-calving interval, remain unknown for many populations. We hypothesized that baleen plates (keratinous strips that grow downward from the palate of mysticete whales) might record previous pregnancies, in the form of high-progesterone regions in the sections of baleen that grew while the whale was pregnant. To test this hypothesis, longitudinal baleen progesterone profiles from two adult female North Atlantic right whales (Eubalaena glacialis) that died as a result of ship strike were compared with dates of known pregnancies inferred from calf sightings and post-mortem data. We sampled a full-length baleen plate from each female at 4 cm intervals from base (newest baleen) to tip (oldest baleen), each interval representing ∼60 days of baleen growth, with high-progesterone areas then sampled at 2 or 1 cm intervals. Pulverized baleen powder was assayed for progesterone using enzyme immunoassay. The date of growth of each sampling location on the baleen plate was estimated based on the distance from the base of the plate and baleen growth rates derived from annual cycles of stable isotope ratios. Baleen progesterone profiles from both whales showed dramatic elevations (two orders of magnitude higher than baseline) in areas corresponding to known pregnancies. Baleen hormone analysis shows great potential for estimation of recent reproductive history, inter-calving interval and general reproductive biology in this species and, possibly, in other mysticete whales. PMID:27293762

Rigor mortis at the myocardium investigated by post-mortem magnetic resonance imaging.

PubMed

Bonzon, Jérôme; Schön, Corinna A; Schwendener, Nicole; Zech, Wolf-Dieter; Kara, Levent; Persson, Anders; Jackowski, Christian

2015-12-01

Post-mortem cardiac MR exams present with different contraction appearances of the left ventricle in cardiac short axis images. It was hypothesized that the grade of post-mortem contraction may be related to the post-mortem interval (PMI) or cause of death and a phenomenon caused by internal rigor mortis that may give further insights in the circumstances of death. The cardiac contraction grade was investigated in 71 post-mortem cardiac MR exams (mean age at death 52 y, range 12-89 y; 48 males, 23 females). In cardiac short axis images the left ventricular lumen volume as well as the left ventricular myocardial volume were assessed by manual segmentation. The quotient of both (LVQ) represents the grade of myocardial contraction. LVQ was correlated to the PMI, sex, age, cardiac weight, body mass and height, cause of death and pericardial tamponade when present. In cardiac causes of death a separate correlation was investigated for acute myocardial infarction cases and arrhythmic deaths. LVQ values ranged from 1.99 (maximum dilatation) to 42.91 (maximum contraction) with a mean of 15.13. LVQ decreased slightly with increasing PMI, however without significant correlation. Pericardial tamponade positively correlated with higher LVQ values. Variables such as sex, age, body mass and height, cardiac weight and cause of death did not correlate with LVQ values. There was no difference in LVQ values for myocardial infarction without tamponade and arrhythmic deaths. Based on the observation in our investigated cases, the phenomenon of post-mortem myocardial contraction cannot be explained by the influence of the investigated variables, except for pericardial tamponade cases. Further research addressing post-mortem myocardial contraction has to focus on other, less obvious factors, which may influence the early post-mortem phase too. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A Longitudinal Study on Human Outdoor Decomposition in Central Texas.

PubMed

Suckling, Joanna K; Spradley, M Katherine; Godde, Kanya

2016-01-01

The development of a methodology that estimates the postmortem interval (PMI) from stages of decomposition is a goal for which forensic practitioners strive. A proposed equation (Megyesi et al. 2005) that utilizes total body score (TBS) and accumulated degree days (ADD) was tested using longitudinal data collected from human remains donated to the Forensic Anthropology Research Facility (FARF) at Texas State University-San Marcos. Exact binomial tests examined the rate of the equation to successfully predict ADD. Statistically significant differences were found between ADD estimated by the equation and the observed value for decomposition stage. Differences remained significant after carnivore scavenged donations were removed from analysis. Low success rates for the equation to predict ADD from TBS and the wide standard errors demonstrate the need to re-evaluate the use of this equation and methodology for PMI estimation in different environments; rather, multivariate methods and equations should be derived that are environmentally specific. © 2015 American Academy of Forensic Sciences.

Developmental Times of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) at Constant Temperatures and Applications in Forensic Entomology.

PubMed

Yang, Yong-Qiang; Li, Xue-Bo; Shao, Ru-Yue; Lyu, Zhou; Li, Hong-Wei; Li, Gen-Ping; Xu, Lyu-Zi; Wan, Li-Hua

2016-09-01

The characteristic life stages of infesting blowflies (Calliphoridae) such as Chrysomya megacephala (Fabricius) are powerful evidence for estimating the death time of a corpse, but an established reference of developmental times for local blowfly species is required. We determined the developmental rates of C. megacephala from southwest China at seven constant temperatures (16-34°C). Isomegalen and isomorphen diagrams were constructed based on the larval length and time for each developmental event (first ecdysis, second ecdysis, wandering, pupariation, and eclosion), at each temperature. A thermal summation model was constructed by estimating the developmental threshold temperature D0 and the thermal summation constant K. The thermal summation model indicated that, for complete development from egg hatching to eclosion, D0 = 9.07 ± 0.54°C and K = 3991.07 ± 187.26 h °C. This reference can increase the accuracy of estimations of postmortem intervals in China by predicting the growth of C. megacephala. © 2016 American Academy of Forensic Sciences.

Succession pattern of carrion-feeding insects in Paramo, Colombia.

PubMed

Martinez, Efrain; Duque, Patricia; Wolff, Marta

2007-03-02

The minimum postmortem interval can be estimated based on knowledge of the pattern of insect succession on a corpse. To use this approach requires that we take into account the rates of insect development associated with particular climatological conditions of the region. This study is the first to look at insect succession on decomposing carcasses in the high altitude plains (Paramo) in Colombia, at 3035 m above sea level. Five stages of decomposition were designated with indicator species identified for each stage: Callíphora nigribasis at the fresh stage; Compsomyiops verena at the bloated stage; Compsomyiops boliviana during active decay; Stearibia nigriceps and Hydrotaea sp. during advanced decay and Leptocera sp. for dry remains. A succession table is presented for carrion-associated species of the region, which can be used for estimating time since death in similar areas. Compsomyiops boliviana is reported for the first time in Colombia.

External foam and the post-mortem period in freshwater drowning; results from a retrospective study in Amsterdam, the Netherlands.

PubMed

Reijnen, G; Buster, M C; Vos, P J E; Reijnders, U J L

2017-11-01

Determining the time of death of bodies recovered from water can be difficult. A feature of drowning is the presence of external foam. This study describes the presence of external foam in relation to the post-mortem period. The study utilizes a database of death reports dated between January 2011 and July 2016. For bodies recovered from fresh water, the presence or absence of external foam was noted. In this study, 112 death reports are included. Of these reports, 18 mentioned external foam, which account for 16.1% of the entire study population. In the population with a post-mortem period of less than 24 h, external foam was detected in 27.7% of cases. All 18 incidents with external foam had an estimated post-mortem period of less than 24 h. In our study, external foam was only present in freshwater drowning cases with a post-mortem period of less than 24 h. Based on this finding, the presence of external foam may be useful as an additional indicator when estimating the time of death in freshwater drowning. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Decreased Brain pH as a Shared Endophenotype of Psychiatric Disorders

PubMed Central

Hagihara, Hideo; Catts, Vibeke S; Katayama, Yuta; Shoji, Hirotaka; Takagi, Tsuyoshi; Huang, Freesia L; Nakao, Akito; Mori, Yasuo; Huang, Kuo-Ping; Ishii, Shunsuke; Graef, Isabella A; Nakayama, Keiichi I; Shannon Weickert, Cynthia; Miyakawa, Tsuyoshi

2018-01-01

Although the brains of patients with schizophrenia and bipolar disorder exhibit decreased brain pH relative to those of healthy controls upon postmortem examination, it remains controversial whether this finding reflects a primary feature of the diseases or is a result of confounding factors such as medication and agonal state. To date, systematic investigation of brain pH has not been undertaken using animal models that can be studied without confounds inherent in human studies. In the present study, we first reevaluated the pH of the postmortem brains of patients with schizophrenia and bipolar disorder by conducting a meta-analysis of existing data sets from 10 studies. We then measured pH, lactate levels, and related metabolite levels in brain homogenates from five neurodevelopmental mouse models of psychiatric disorders, including schizophrenia, bipolar disorder, and autism spectrum disorder. All mice were drug naive with the same agonal state, postmortem interval, and age within each strain. Our meta-analysis revealed that brain pH was significantly lower in patients with schizophrenia and bipolar disorder than in control participants, even when a few potential confounding factors (postmortem interval, age, and history of antipsychotic use) were considered. In animal experiments, we observed significantly lower pH and higher lactate levels in the brains of model mice relative to controls, as well as a significant negative correlation between pH and lactate levels. Our findings suggest that lower pH associated with increased lactate levels is not a mere artifact, but rather implicated in the underlying pathophysiology of schizophrenia and bipolar disorder. PMID:28776581

First survey of forensically important insects from human corpses in Shiraz, Iran.

PubMed

Moemenbellah-Fard, Mohammad D; Keshavarzi, Davood; Fereidooni, Mehran; Soltani, Aboozar

2018-02-01

The presence of insects on human cadavers has potential judicial value in medicolegal cases. This research emphasized the important role of insects in postmortem decomposition. It was conducted to investigate the composition and abundance of insects from human corpses during autopsies in legal medicine. It was implemented in the city of Shiraz, south Iran. Insects associated with human corpses were carefully collected and put into labelled vials. They were then identified using valid taxonomic keys. Fifteen outdoor (67%) and indoor discovered cadavers were examined. All but one was covered at the time of discovery. From these several species of entomofauna played important roles in the minimum postmortem interval (minPMI) estimate. Insects included the orders of Diptera and Coleoptera. Overall, 14 different species of arthropods were identified. Within Diptera, 2 families of Sarcophagidae and Calliphoridae were present in 73% of the cases with Calliphora vicina Robineau-Desvoidy and Chrysomya albiceps Wiedemann accounting for about half of the cases. The latter family members, Calliphoridae, were more frequently (52%) collected in autumn and winter. Only 4/15 outdoor cadavers had beetles. Four species of Coleopterans; namely Dermestes frischii Kugelann, Nitidula flavomaculata Rossi, Creophilus maxillosus Linnaeus and Saprinus chalcites Illiger; were recorded for the first time from 3 corpses in Iran. The presence and diversity of different insects on human corpses could contribute to the advancement of forensic entomology knowledge and the refined estimates of minPMI in medicolegal cases. Copyright © 2017. Published by Elsevier Ltd.

Soilwater Conductivity Analysis to Date and Locate Clandestine Graves of Homicide Victims.

PubMed

Pringle, Jamie K; Cassella, John P; Jervis, John R; Williams, Anna; Cross, Peter; Cassidy, Nigel J

2015-07-01

In homicide investigations, it is critically important that postmortem interval and postburial interval (PBI) of buried victims are determined accurately. However, clandestine graves can be difficult to locate; and the detection rates for a variety of search methods (ranging from simple ground probing through to remote imaging and near-surface geophysics) can be very low. In this study, simulated graves of homicide victims were emplaced in three sites with contrasting soil types, bedrock, and depositional environments. The long-term monthly in situ monitoring of grave soil water revealed rapid increases in conductivity up to 2 years after burial, with the longest study evidencing declining values to background levels after 4.25 years. Results were corrected for site temperatures and rainfall to produce generic models of fluid conductivity as a function of time. The research suggests soilwater conductivity can give reliable PBI estimates for clandestine burials and therefore be used as a grave detection method. © 2015 American Academy of Forensic Sciences.

The Effect of Clothing on the Rate of Decomposition and Diptera Colonization on Sus scrofa Carcasses.

PubMed

Card, Allison; Cross, Peter; Moffatt, Colin; Simmons, Tal

2015-07-01

Twenty Sus scrofa carcasses were used to study the effect the presence of clothing had on decomposition rate and colonization locations of Diptera species; 10 unclothed control carcasses were compared to 10 clothed experimental carcasses over 58 days. Data collection occurred at regular accumulated degree day intervals; the level of decomposition as Total Body Score (TBSsurf ), pattern of decomposition, and Diptera present was documented. Results indicated a statistically significant difference in the rate of decomposition, (t427  = 2.59, p = 0.010), with unclothed carcasses decomposing faster than clothed carcasses. However, the overall decomposition rates from each carcass group are too similar to separate when applying a 95% CI, which means that, although statistically significant, from a practical forensic point of view they are not sufficiently dissimilar as to warrant the application of different formulae to estimate the postmortem interval. Further results demonstrated clothing provided blow flies with additional colonization locations. © 2015 American Academy of Forensic Sciences.

Differential Diptera succession patterns onto partially burned and unburned pig carrion in southeastern Brazil.

PubMed

Oliveira-Costa, J; Lamego, C M D; Couri, M S; Mello-Patiu, C A

2014-11-01

In the present contribution we compared the entomological succession pattern of a burned carcass with that of an unburned one. For that, we used domestic pig carcasses and focused on Calliphoridae, Muscidae and Sarcophagidae flies, because they are the ones most commonly used in Postmortem Interval estimates. Adult and immature flies were collected daily. A total of 27 species and 2,498 specimens were collected, 1,295 specimens of 26 species from the partially burned carcass and 1,203 specimens of 22 species from the control carcass (unburned). The species composition in the two samples differed, and the results of the similarity measures were 0.875 by Sorensen and 0.756 by Bray-Curtis index. The results obtained for both carcasses also differ with respect to the decomposition process, indicating that the post mortem interval would be underestimated if the entomological succession pattern observed for a carcass under normal conditions was applied to a carbonized carcass.

A review of postfeeding larval dispersal in blowflies: implications for forensic entomology

NASA Astrophysics Data System (ADS)

Gomes, Leonardo; Godoy, Wesley Augusto Conde; von Zuben, Claudio José

2006-05-01

Immature and adult stages of blowflies are one of the primary invertebrate consumers of decomposing animal organic matter. When the food supply is consumed or when the larvae complete their development and migrate prior to the total removal of the larval substrate, they disperse to find adequate places for pupation, a process known as postfeeding larval dispersal. Several important ecological and physiological aspects of this process were studied since the work by Green (Ann Appl Biol 38:475, 1951) 50 years ago. An understanding of postfeeding larval dispersal can be useful for determining the postmortem interval (PMI) of human cadavers in legal medicine, particularly because this interval may be underestimated if older dispersing larvae or those that disperse longer, faster, and deeper are not taken into account. In this article, we review the process of postfeeding larval dispersal and its implications for legal medicine, in particular showing that aspects such as burial behavior and competition among species of blowflies can influence this process and consequently, the estimation of PMI.

The Stone Cold Truth: The Effect of Concrete Encasement on the Rate and Pattern of Soft Tissue Decomposition.

PubMed

Martin, D C; Dabbs, Gretchen R; Roberts, Lindsey G; Cleary, Megan K

2016-03-01

This study provides a descriptive analysis of taphonomic changes observed in the soft tissue of ten pigs (Sus scrofa) after being encased in Quickrete (®) concrete and excavated at monthly or bimonthly intervals over the course of 2 years. The best method of subject excavation was investigated. Rate and pattern of decomposition were compared to a nonencased control subject. Results demonstrate subjects interred in concrete decomposed significantly slower than the control subject (p < 0.01), the difference being observable after 1 month. After 1 year, the encased subject was in the early stage of decomposition with purging fluids and intact organs present, versus complete skeletonization of the control subject. Concrete subjects also display a unique decomposition pattern, exhibiting a chemically burned outer layer of skin and a common separation of the dermal and epidermal layers. Results suggest using traditional methods to estimate postmortem interval on concrete subjects may result in underestimation. © 2015 American Academy of Forensic Sciences.

Sampling flies or sampling flaws? Experimental design and inference strength in forensic entomology.

PubMed

Michaud, J-P; Schoenly, Kenneth G; Moreau, G

2012-01-01

Forensic entomology is an inferential science because postmortem interval estimates are based on the extrapolation of results obtained in field or laboratory settings. Although enormous gains in scientific understanding and methodological practice have been made in forensic entomology over the last few decades, a majority of the field studies we reviewed do not meet the standards for inference, which are 1) adequate replication, 2) independence of experimental units, and 3) experimental conditions that capture a representative range of natural variability. Using a mock case-study approach, we identify design flaws in field and lab experiments and suggest methodological solutions for increasing inference strength that can inform future casework. Suggestions for improving data reporting in future field studies are also proposed.

Best practice in forensic entomology--standards and guidelines.

PubMed

Amendt, Jens; Campobasso, Carlo P; Gaudry, Emmanuel; Reiter, Christian; LeBlanc, Hélène N; Hall, Martin J R

2007-03-01

Forensic entomology, the use of insects and other arthropods in forensic investigations, is becoming increasingly more important in such investigations. To ensure its optimal use by a diverse group of professionals including pathologists, entomologists and police officers, a common frame of guidelines and standards is essential. Therefore, the European Association for Forensic Entomology has developed a protocol document for best practice in forensic entomology, which includes an overview of equipment used for collection of entomological evidence and a detailed description of the methods applied. Together with the definitions of key terms and a short introduction to the most important methods for the estimation of the minimum postmortem interval, the present paper aims to encourage a high level of competency in the field of forensic entomology.

Size at emergence improves accuracy of age estimates in forensically-useful beetle Creophilus maxillosus L. (Staphylinidae).

PubMed

Matuszewski, Szymon; Frątczak-Łagiewska, Katarzyna

2018-02-05

Insects colonizing human or animal cadavers may be used to estimate post-mortem interval (PMI) usually by aging larvae or pupae sampled on a crime scene. The accuracy of insect age estimates in a forensic context is reduced by large intraspecific variation in insect development time. Here we test the concept that insect size at emergence may be used to predict insect physiological age and accordingly to improve the accuracy of age estimates in forensic entomology. Using results of laboratory study on development of forensically-useful beetle Creophilus maxillosus (Linnaeus, 1758) (Staphylinidae) we demonstrate that its physiological age at emergence [i.e. thermal summation value (K) needed for emergence] fall with an increase of beetle size. In the validation study it was found that K estimated based on the adult insect size was significantly closer to the true K as compared to K from the general thermal summation model. Using beetle length at emergence as a predictor variable and male or female specific model regressing K against beetle length gave the most accurate predictions of age. These results demonstrate that size of C. maxillosus at emergence improves accuracy of age estimates in a forensic context.

Heat-related deaths in Philadelphia--1993.

PubMed

Mirchandani, H G; McDonald, G; Hood, I C; Fonseca, C

1996-06-01

A study of heat-related deaths associated with the 1993 heat wave in Philadelphia, Pennsylvania, was conducted. Most of these deaths were in the susceptible elderly with preexisting natural diseases who lived alone without air conditioning in upstairs bedrooms with windows shut, thus creating an even hotter environment. These excessive deaths under such conditions did not meet the standard clinical criteria for hyperthermia because of varying postmortem intervals. Therefore, the authors stress the utility of a postmortem definition of heat-related death to better define the magnitude of health risk posed by hot weather and warn public health and other agencies to take preventative measures.

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

PubMed

Carvajal-Zarrabal, Octavio; Hayward-Jones, Patricia M; Nolasco-Hipolito, Cirilo; Barradas-Dermitz, Dulce Ma; Calderón-Garcidueñas, Ana Laura; López-Amador, Noé

2017-09-01

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. © 2017 American Academy of Forensic Sciences.

Introducing forensic entomology in cases of suspected animal neglect.

PubMed

McGarry, John; Ratsep, Emily; Ressel, Lorenzo; Leeming, Gail; Ricci, Emanuele; Verin, Ranieri; Blundell, Richard; Kipar, Anja; Hetzel, Udo; Yeates, James

2018-02-03

Cases of arthropod-infested, abandoned or abused animals are sometimes brought to the attention of veterinarians by animal welfare authorities, with the requirement for a full postmortem examination towards criminal or civil proceedings. In these situations, entomology is an important support tool for the pathologists' investigation since the presence of arthropod life cycle stages serve as reliable forensic markers, especially for blowflies which form the first waves of activity following death. In the present study, 70 cadavers from a total of 544 referred to the Institute of Veterinary Science, University of Liverpool, between 2009 and 2014 displayed evidence of infestation. Here, the authors introduce principles of applied entomology and simplified approaches for estimating the minimum time since death, relevant in the context of routine submissions and the broad remit of individual cases. Despite often limited availability of scene of the crime and local thermal data, the interpretation of the minimum postmortem interval has nonetheless proved valuable as an adjunct to the expert pathology report. However, future developments and enhanced accuracy in this area of animal welfare require resource and training in expertise, and agreed standardisation of both laboratory and field procedures. © British Veterinary Association (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Measurement of cerebral biomarkers proving traumatic brain injuries in post-mortem body fluids.

PubMed

Ondruschka, Benjamin; Sieber, Monique; Kirsten, Holger; Franke, Heike; Dressler, Jan

2018-05-05

Until now, it is impossible to identify a fatal traumatic brain injury (TBI) before post-mortem radiological investigations or an autopsy take place. It would be preferable to have an additional diagnostic tool like post-mortem biochemistry to get greater insight into the pathological pathways and survival times after sustaining TBI. Cerebrospinal fluid (CSF) and serum samples of 84 autopsy cases were collected from forensic autopsies with post-mortem intervals (PMI) of up to 148 h. The cases were categorized into a fatal TBI case group (n=42) and non-TBI controls (n=42). The values of glial fibrillary acidic protein (GFAP), brain-derived neurotrophic factor (BDNF) and neutrophil gelatinase-associated lipocalin (NGAL) were analyzed by means of quantitative chemiluminescent multiplex immunoassays. The main results indicate that the usage of liquid samples with good macroscopic quality is more relevant for meaningful biomarker analyses than the length of the PMI. All three proteins were shown to differentiate TBI fatalities from the controls in CSF. In serum, only GFAP could be shown to be able to identify TBI cases. This study is the first approach to measure the three proteins together in CSF and serum in autopsy cases. Determined threshold values may differentiate between fatal TBI and control cases. The presented results emphasize the possible use of post-mortem biochemistry as a supplemental tool in everyday forensic routine.

Broiler skin and meat color changes during storage.

PubMed

Petracci, M; Fletcher, D L

2002-10-01

The importance of poultry skin and meat color (both absolute and variations in color) in the market place have been well established. It has also been reported that these colors change over time. With the development of computer-assisted vision grading systems, the changes in skin and meat color during and after processing have become important, based on calibrations and assessment values based on color. Four independent experiments were conducted to determine the pattern of color change in broiler skin and meat during processing and storage. Skin color change was measured on subscald (57 C) and semiscald (50 C) breast skin surfaces and on breast and leg meat, on the carcass and following deboning and packaging. A reflectance colorimeter was used to determine lightness (L*), redness (a*), and yellowness (b*) at 20-min intervals for the first 3 h, at 30-min intervals between 3 and 8 h, hourly between 8 and 12 h, and daily up to 8 d postmortem. Results clearly show that color values for both skin and meat changed dramatically for the first 6 h postmortem, after which the changes were less pronounced. The skin from semiscalded birds showed less change than the skin from subscalded birds. These results indicate that on-line vision systems need to take into account the dramatic changes in skin and meat color during the first 6 h postmortem, after which the color changes may be less important.

DNA and RNA profiling of excavated human remains with varying postmortem intervals.

PubMed

van den Berge, M; Wiskerke, D; Gerretsen, R R R; Tabak, J; Sijen, T

2016-11-01

When postmortem intervals (PMIs) increase such as with longer burial times, human remains suffer increasingly from the taphonomic effects of decomposition processes such as autolysis and putrefaction. In this study, various DNA analysis techniques and a messenger RNA (mRNA) profiling method were applied to examine for trends in nucleic acid degradation and the postmortem interval. The DNA analysis techniques include highly sensitive DNA quantitation (with and without degradation index), standard and low template STR profiling, insertion and null alleles (INNUL) of retrotransposable elements typing and mitochondrial DNA profiling. The used mRNA profiling system targets genes with tissue specific expression for seven human organs as reported by Lindenbergh et al. (Int J Legal Med 127:891-900, 27) and has been applied to forensic evidentiary traces but not to excavated tissues. The techniques were applied to a total of 81 brain, lung, liver, skeletal muscle, heart, kidney and skin samples obtained from 19 excavated graves with burial times ranging from 4 to 42 years. Results show that brain and heart are the organs in which both DNA and RNA remain remarkably stable, notwithstanding long PMIs. The other organ tissues either show poor overall profiling results or vary for DNA and RNA profiling success, with sometimes DNA and other times RNA profiling being more successful. No straightforward relations were observed between nucleic acid profiling results and the PMI. This study shows that not only DNA but also RNA molecules can be remarkably stable and used for profiling of long-buried human remains, which corroborate forensic applications. The insight that the brain and heart tissues tend to provide the best profiling results may change sampling policies in identification cases of degrading cadavers.

Study on the postmortem submersion interval and accumulated degree days for a multiple drowning accident.

PubMed

Mateus, M; Vieira, V

2014-05-01

Recreational accidents in aquatic environments leading to death by drowning are quite frequent. Even if they do not usually require forensic investigation, they may provide useful information on the post mortem submersion interval (PMSI) and its relation with accumulated degree days (ADD). This is particularly useful to forensic science since most studies dealing with these matters rely mostly on animal carcasses as human analogues. In this work we report on a multiple drowning accident resulting in 6 victims. ADD was calculated based on the PMSI and water temperature during this period. PMSI varied between ∼7.4 days and ∼11.4 days, and estimated body drift from the accident site ranged from 0.5km to 8.0km. Surface water temperature in the accident area showed little variation during the PMSI (14.5-16.0°C). Estimated ADD varied between 115°C and 174°C, and between 104°C and 191°C when considering the cumulative lower (ADDmin) and upper (ADDmax) limits for ADD. We compare the results with recently published data on two similar cases, and suggest a range for ADD that can be assumed as necessary before body floatability is regain after a drowning accident. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Influence of hypo- and hyperthermia on death time estimation - A simulation study.

PubMed

Muggenthaler, H; Hubig, M; Schenkl, S; Mall, G

2017-09-01

Numerous physiological and pathological mechanisms can cause elevated or lowered body core temperatures. Deviations from the physiological level of about 37°C can influence temperature based death time estimations. However, it has not been investigated by means of thermodynamics, to which extent hypo- and hyperthermia bias death time estimates. Using numerical simulation, the present study investigates the errors inherent in temperature based death time estimation in case of elevated or lowered body core temperatures before death. The most considerable errors with regard to the normothermic model occur in the first few hours post-mortem. With decreasing body core temperature and increasing post-mortem time the error diminishes and stagnates at a nearly constant level. Copyright © 2017 Elsevier B.V. All rights reserved.

Mortality in East African shorthorn zebu cattle under one year: predictors of infectious-disease mortality.

PubMed

Thumbi, Samuel M; Bronsvoort, Mark B M de C; Kiara, Henry; Toye, P G; Poole, Jane; Ndila, Mary; Conradie, Ilana; Jennings, Amy; Handel, Ian G; Coetzer, J A W; Steyl, Johan; Hanotte, Olivier; Woolhouse, Mark E J

2013-09-08

Infectious livestock diseases remain a major threat to attaining food security and are a source of economic and livelihood losses for people dependent on livestock for their livelihood. Knowledge of the vital infectious diseases that account for the majority of deaths is crucial in determining disease control strategies and in the allocation of limited funds available for disease control. Here we have estimated the mortality rates in zebu cattle raised in a smallholder mixed farming system during their first year of life, identified the periods of increased risk of death and the risk factors for calf mortality, and through analysis of post-mortem data, determined the aetiologies of calf mortality in this population. A longitudinal cohort study of 548 zebu cattle was conducted between 2007 and 2010. Each calf was followed during its first year of life or until lost from the study. Calves were randomly selected from 20 sub-locations and recruited within a week of birth from different farms over a 45 km radius area centered on Busia in the Western part of Kenya. The data comprised of 481.1 calf years of observation. Clinical examinations, sample collection and analysis were carried out at 5 week intervals, from birth until one year old. Cox proportional hazard models with frailty terms were used for the statistical analysis of risk factors. A standardized post-mortem examination was conducted on all animals that died during the study and appropriate samples collected. The all-cause mortality rate was estimated at 16.1 (13.0-19.2; 95% CI) per 100 calf years at risk. The Cox models identified high infection intensity with Theileria spp., the most lethal of which causes East Coast Fever disease, infection with Trypanosome spp., and helminth infections as measured by Strongyle spp. eggs per gram of faeces as the three important infections statistically associated with infectious disease mortality in these calves. Analysis of post-mortem data identified East Coast Fever as the main cause of death accounting for 40% of all deaths, haemonchosis 12% and heartwater disease 7%. The findings demonstrate the impact of endemic parasitic diseases in indigenous animals expected to be well adapted against disease pressures. Additionally, agreement between results of Cox models using data from simple diagnostic procedures and results from post-mortem analysis underline the potential use such diagnostic data to reduce calf mortality. The control strategies for the identified infectious diseases have been discussed.

Meta-analyses of the sensitivity and specificity of ante-mortem and post-mortem diagnostic tests for bovine tuberculosis in the UK and Ireland.

PubMed

Nuñez-Garcia, Javier; Downs, Sara H; Parry, Jessica E; Abernethy, Darrell A; Broughan, Jennifer M; Cameron, Angus R; Cook, Alasdair J; de la Rua-Domenech, Ricardo; Goodchild, Anthony V; Gunn, Jane; More, Simon J; Rhodes, Shelley; Rolfe, Simon; Sharp, Michael; Upton, Paul A; Vordermeier, H Martin; Watson, Eamon; Welsh, Michael; Whelan, Adam O; Woolliams, John A; Clifton-Hadley, Richard S; Greiner, Matthias

2018-05-01

Bovine Tuberculosis (bTB) in cattle is a global health problem and eradication of the disease requires accurate estimates of diagnostic test performance to optimize their efficiency. The objective of this study was, through statistical meta-analyses, to obtain estimates of sensitivity (Se) and specificity (Sp), for 14 different ante-mortem and post-mortem diagnostic tests for bTB in cattle. Using data from a systematic review of the scientific literature (published 1934-2009) diagnostic Se and Sp were estimated using Bayesian logistic regression models adjusting for confounding factors. Random effect terms were used to account for unexplained heterogeneity. Parameters in the models were implemented using Markov Chain Monte Carlo (MCMC), and posterior distributions for the diagnostic parameters with adjustment for covariates (confounding factors) were obtained using the inverse logit function. Estimates for Se and/or Sp of the tuberculin skin tests and the IFN-γ blood test were compared with estimates published 2010-2015. Median Se for the single intradermal comparative cervical tuberculin skin (SICCT) test (standard interpretation) was 0.50 and Bayesian credible intervals (CrI) were wide (95% CrI 0.26, 0.78). Median Sp for the SICCT test was 1.00 (95% CrI 0.99, 1.00). Estimates for the IFN-γ blood test Bovine Purified Protein Derivative (PPD)-Avian PPD and Early Secreted Antigen target 6 and Culture Filtrate Protein 10 (ESAT-6/CFP10) ESAT6/CFP10 were 0.67 (95% CrI 0.49, 0.82) and 0.78 (95% CrI 0.60, 0.90) respectively for Se, and 0.98 (95% CrI 0.96, 0.99) and 0.99 (95% CrI 0.99, 1.00) for Sp. The study provides an overview of the accuracy of a range of contemporary diagnostic tests for bTB in cattle. Better understanding of diagnostic test performance is essential for the design of effective control strategies and their evaluation. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Comparison of protocols for measuring and calculating postmortem submersion intervals for human analogs in fresh water.

PubMed

Humphreys, Michael K; Panacek, Edward; Green, William; Albers, Elizabeth

2013-03-01

Protocols for determining postmortem submersion interval (PMSI) have long been problematic for forensic investigators due to the wide variety of factors affecting the rate of decomposition of submerged carrion. Likewise, it has been equally problematic for researchers to develop standardized experimental protocols to monitor underwater decomposition without artificially affecting the decomposition rate. This study compares two experimental protocols: (i) underwater in situ evaluation with photographic documentation utilizing the Heaton et al. total aquatic decomposition (TAD) score and (ii) weighing the carrion before and after submersion. Complete forensic necropsies were performed as a control. Perinatal piglets were used as human analogs. The results of this study indicate that in order to objectively measure decomposition over time, the human analog should be examined at depth using the TAD scoring system rather than utilizing a carrion weight evaluation. The acquired TAD score can be used to calculate an approximate PMSI. © 2012 American Academy of Forensic Sciences.

Potential use of hydrocarbons for aging Lucilia sericata blowfly larvae to establish the postmortem interval.

PubMed

Moore, Hannah E; Adam, Craig D; Drijfhout, Falko P

2013-03-01

Previous studies on Diptera have shown the potential for the use of cuticular hydrocarbons' analysis in the determination of larval age and hence the postmortem interval (PMI) for an associated cadaver. In this work, hydrocarbon compounds, extracted daily until pupation from the cuticle of the blowfly Lucilia sericata (Diptera: Calliphoridae), have been analyzed using gas chromatography-mass spectrometry (GC-MS). The results show distinguishing features within the hydrocarbon profile over the period of the larvae life cycle, with significant chemical changes occurring from the younger larvae to the postfeeding larvae. Further interpretation of the chromatograms using principal component analysis revealed a strong correlation between the magnitudes of particular principal components and time. This outcome suggests that, under the conditions of this study, the cuticular hydrocarbons evolve in a systematic fashion with time, thus supporting the potential for GC-MS analysis as a tool for establishing PMI where such a species is present. © 2012 American Academy of Forensic Sciences.

Sex- and Size-Related Patterns of Carrion Visitation in Necrodes littoralis (Coleoptera: Silphidae) and Creophilus maxillosus (Coleoptera: Staphylinidae).

PubMed

Mądra-Bielewicz, Anna; Frątczak-Łagiewska, Katarzyna; Matuszewski, Szymon

2017-09-01

The estimation of postmortem interval (PMI) based on successional patterns of adult insects is largely limited, due to the lack of potential PMI markers. Sex and size of adult insects could be easily used for such estimation. In this study, sex- and size-related patterns of carrion attendance by adult insects were analyzed in Necrodes littoralis (Coleoptera: Silphidae) and Creophilus maxillosus (Coleoptera: Staphylinidae). For both species, abundance of males and females changed similarly during decomposition. A slightly female-biased sex ratio was recorded in N. littoralis. Females of N. littoralis started visiting carcasses, on average, one day earlier than males. There was a rise in size of males of N. littoralis at the end of decomposition, whereas for females of both species and males of C. maxillosus, no size-related patterns of carrion visitation were found. Current results demonstrate that size and sex of adult carrion beetles are poor indicators of PMI. © 2016 American Academy of Forensic Sciences.

Volatile organic compounds released by blowfly larvae and pupae: new perspectives in forensic entomology.

PubMed

Frederickx, C; Dekeirsschieter, J; Brostaux, Y; Wathelet, J-P; Verheggen, F J; Haubruge, E

2012-06-10

To evaluate postmortem intervals (PMIs), one should take into account the determined age of necrophagous flies present on the cadaver. However, PMI determination needs further improvement, and rapid and accurate approaches have therefore to be developed. While previous studies have focussed on insect cuticular hydrocarbons, here we explore the volatile profile released by larvae and pupae of Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae). We monitored changes in volatile compounds daily, by headspace solid-phase microextraction, followed by gas chromatography-mass spectrometry. Branched and unbranched hydrocarbons, alcohols, esters and acids were identified, and the volatile profile was shown to vary, in both composition and quantity, with the age of the larva/pupa under investigation. We concluded, based on the analysis of the released volatile organic compounds, that it is possible to increase the accuracy of the estimated PMI, through improved estimation of the age of blowflies present on the cadaver. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Breast Tissue Characterization with Photon-counting Spectral CT Imaging: A Postmortem Breast Study

PubMed Central

Ding, Huanjun; Klopfer, Michael J.; Ducote, Justin L.; Masaki, Fumitaro

2014-01-01

Purpose To investigate the feasibility of breast tissue characterization in terms of water, lipid, and protein contents with a spectral computed tomographic (CT) system based on a cadmium zinc telluride (CZT) photon-counting detector by using postmortem breasts. Materials and Methods Nineteen pairs of postmortem breasts were imaged with a CZT-based photon-counting spectral CT system with beam energy of 100 kVp. The mean glandular dose was estimated to be in the range of 1.8–2.2 mGy. The images were corrected for pulse pile-up and other artifacts by using spectral distortion corrections. Dual-energy decomposition was then applied to characterize each breast into water, lipid, and protein contents. The precision of the three-compartment characterization was evaluated by comparing the composition of right and left breasts, where the standard error of the estimations was determined. The results of dual-energy decomposition were compared by using averaged root mean square to chemical analysis, which was used as the reference standard. Results The standard errors of the estimations of the right-left correlations obtained from spectral CT were 7.4%, 6.7%, and 3.2% for water, lipid, and protein contents, respectively. Compared with the reference standard, the average root mean square error in breast tissue composition was 2.8%. Conclusion Spectral CT can be used to accurately quantify the water, lipid, and protein contents in breast tissue in a laboratory study by using postmortem specimens. © RSNA, 2014 PMID:24814180

Paper-based microfluidic devices on the crime scene: A simple tool for rapid estimation of post-mortem interval using vitreous humour.

PubMed

Garcia, Paulo T; Gabriel, Ellen F M; Pessôa, Gustavo S; Santos Júnior, Júlio C; Mollo Filho, Pedro C; Guidugli, Ruggero B F; Höehr, Nelci F; Arruda, Marco A Z; Coltro, Wendell K T

2017-06-29

This paper describes for the first time the use of paper-based analytical devices at crime scenes to estimate the post-mortem interval (PMI), based on the colorimetric determination of Fe 2+ in vitreous humour (VH) samples. Experimental parameters such as the paper substrate, the microzone diameter, the sample volume and the 1,10-phenanthroline (o-phen) concentration were optimised in order to ensure the best analytical performance. Grade 1 CHR paper, microzone with diameter of 5 mm, a sample volume of 4 μL and an o-phen concentration of 0.05 mol/L were chosen as the optimum experimental conditions. A good linear response was observed for a concentration range of Fe 2+ between 2 and 10 mg/L and the calculated values for the limit of detection (LOD) and limit of quantification (LOQ) were 0.3 and 0.9 mg/L, respectively. The specificity of the Fe 2+ colorimetric response was tested in the presence of the main interfering agents and no significant differences were found. After selecting the ideal experimental conditions, four HV samples were investigated on paper-based devices. The concentration levels of Fe 2+ achieved for samples #1, #2, #3 and #4 were 0.5 ± 0.1, 0.7 ± 0.1, 1.2 ± 0.1 and 15.1 ± 0.1 mg/L, respectively. These values are in good agreement with those calculated by ICP-MS. It important to note that the concentration levels measured using both techniques are proportional to the PMI. The limitation of the proposed analytical device is that it is restricted to a PMI greater than 1 day. The capability of providing an immediate answer about the PMI on the crime scene without any sophisticated instrumentation is a great achievement in modern instrumentation for forensic chemistry. The strategy proposed in this study could be helpful in many criminal investigations. Copyright © 2017 Elsevier B.V. All rights reserved.

Association between diabetes mellitus, hypothyroidism or hyperadrenocorticism, and atherosclerosis in dogs.

PubMed

Hess, Rebecka S; Kass, Philip H; Van Winkle, Thomas J

2003-01-01

The objective of this study was to determine whether dogs with atherosclerosis are more likely to have concurrent diabetes mellitus, hypothyroidism, or hyperadrenocorticism than dogs that do not have atherosclerosis. A retrospective mortality prevalence case-control study was performed. The study group included 30 dogs with histopathological evidence of atherosclerosis. The control group included 142 dogs with results of a complete postmortem examination, a final postmortem examination diagnosis of neoplasia, and no histopathological evidence of atherosclerosis. Control dogs were frequency matched for age and year in which the postmortem examination was performed. Proportionate changes in the prevalence of diabetes mellitus, hypothyroidism, and hyperadrenocorticism were calculated by exact prevalence odds ratios (POR), 95% confidence intervals (95% CI), and P values. Multiple logistic regression analysis was used to examine the combined effects of prevalence determinants while controlling for age and year of postmortem examination. Dogs with atherosclerosis were over 53 times more likely to have concurrent diabetes mellitus than dogs without atherosclerosis (POR = 53.6; 95% CI, 4.6-627.5; P = .002) and over 51 times more likely to have concurrent hypothyroidism than dogs without atherosclerosis (POR = 51.1; 95% CI, 14.5-180.1; P < .001). Dogs with atherosclerosis were not found to be more likely to have concurrent hyperadrenocorticism than dogs that did not have atherosclerosis (POR = 1.8; 95% CI, 0.2-17.6; P = .59). Diabetes mellitus and hypothyroidism, but not hyperadrenocorticism, are more prevalent in dogs with atherosclerosis compared to dogs without atherosclerosis on postmortem examination.

Smaller but denser: postmortem changes alter the CT characteristics of subdural hematomas.

PubMed

Berger, Nicole; Ebert, Lars C; Ampanozi, Garyfalia; Flach, Patricia M; Gascho, Dominic; Thali, Michael J; Ruder, Thomas D

2015-03-01

The aim of this study was to investigate if (1) the volume of subdural hematomas (SDH), midline shift, and CT density of subdural hematomas are altered by postmortem changes and (2) if these changes are dependent on the postmortem interval (PMI). Ante mortem computed tomography (AMCT) of the head was compared to corresponding postmortem CT (PMCT) in 19 adults with SDH. SDH volume, midline shift, and hematoma density were measured on both AMCT and PMCT and their differences assessed using Wilcoxon-Signed Rank Test. Spearman's Rho Test was used to assess significant correlations between the PMI and the alterations of SDH volume, midline shift, and hematoma density. Mean time between last AMCT and PMCT was 109 h, mean PMI was 35 h. On PMCT mean midline displacement was decreased by 57% (p < 0.001); mean SDH volume was decreased by 38% (p < 0.001); and mean hematoma density was increased by 18% (p < 0.001) in comparison to AMCT. There was no correlation between the PMI and the normalization of the midline shift (p = 0.706), the reduction of SDH volume (p = 0.366), or the increase of hematoma density (p = 0.140). This study reveals that normal postmortem changes significantly affect the extent and imaging characteristics of subdural hematoma and may therefore affect the interpretation of these findings on PMCT. Radiologists and forensic pathologists who use PMCT must be aware of these phenomena in order to correctly interpret PMCT findings in cases of subdural hemorrhages.

Interpretation of postmortem vitreous concentrations of sodium and chloride.

PubMed

Zilg, B; Alkass, K; Berg, S; Druid, H

2016-06-01

Vitreous fluid can be used to analyze sodium and chloride levels in deceased persons, but it remains unclear to what extent such results can be used to diagnose antemortem sodium or chloride imbalances. In this study we present vitreous sodium and chloride levels from more than 3000 cases. We show that vitreous sodium and chloride levels both decrease with approximately 2.2mmol/L per day after death. Since potassium is a well-established marker for postmortem interval (PMI) and easily can be analyzed along with sodium and chloride, we have correlated sodium and chloride levels with the potassium levels and present postmortem reference ranges relative the potassium levels. We found that virtually all cases outside the reference range show signs of antemortem hypo- or hypernatremia. Vitreous sodium or chloride levels can be the only means to diagnose cases of water or salt intoxication, beer potomania or dehydration. We further show that postmortem vitreous sodium and chloride strongly correlate and in practice can be used interchangeably if analysis of one of the ions fails. It has been suggested that vitreous sodium and chloride levels can be used to diagnose drowning or to distinguish saltwater from freshwater drowning. Our results show that in cases of freshwater drowning, vitreous sodium levels are decreased, but that this mainly is an effect of postmortem diffusion between the eye and surrounding water rather than due to the drowning process, since the decrease in sodium levels correlates with immersion time. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The effect of post-mortem ageing and heating on water retention in bovine muscles.

PubMed

Kołczak, Tadeusz; Krzysztoforski, Krzysztof; Palka, Krystyna

2007-04-01

The muscles semitendinosus (ST) and psoas major (PM) were removed from chilled young bull carcasses 24h after slaughter and stored at 4°C. At the 1st, 6th and 12th day of post-mortem ageing the chemical composition (moisture, fat, protein, collagen) and contents of free, immobilized and unfreezable water in the muscles were estimated. The muscle steaks were boiled at 100°C, roasted at 170°C or fried at 160°C to an internal temperature of 75°C, and the amounts of total, free, immobilized, and unfreezable water in heated muscles were evaluated. The unfreezable water was estimated by DSC. In the raw muscles immobilized water constituted 74-75%, free water 16.6-17.6% and unfreezable water 7-8% of the total water. Independent of time of ageing, PM muscle contained significantly more free water than ST muscle. During post-mortem ageing, changes in free, immobilized and unfreezable water in muscles were not significant. The level of free water was highest in boiled and least in fried meat, however the amount of immobilized water was highest in fried and lowest in boiled meat. The amount of unfreezable water in muscles heated after 12 days of post-mortem ageing decreased.

The temporal degradation of bone collagen: A histochemical approach.

PubMed

Boaks, Amelia; Siwek, Donald; Mortazavi, Farzad

2014-07-01

As forensic anthropologists are currently unable to estimate reliably and quantitatively the postmortem interval (PMI) of skeletonized remains, the current study was conducted to determine if degradation of bone collagen over time could be quantified using sirius red/fast green staining, and whether the degradation would occur at a predictive rate such that it may be used to estimate the PMI of skeletonized individuals. Resin embedded 200-300μm cross-sections of pig (Sus scrofa) long bones with known provenience and PMIs ranging from fresh to 12 months were stained using a histochemical reaction which differentially stains collagenous (Co) and non-collagenous (NCo) proteins. Spectrophotometry was used to determine the concentration of Co and NCo proteins in each bone section, after which the ratio of these proteins was calculated. The results of this study revealed a significant decline in the ratios of Co/NCo protein concentrations over the time period studied (p<0.001). Furthermore, a significant negative correlation between the ratios of Co/NCo protein concentrations and time (r=-0.563, p<0.0001) was observed. Despite a significant correlation, the moderate r-value obtained suggests that, at present, this method is useful primarily for detecting and quantifying the degradation of Co and NCo proteins in bones. Future studies that include shorter time intervals and environmental factors, such as soil pH, temperature, and hydrology may prove to be critical for using this method for PMI estimation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Characterization of postmortem biochemical changes in rabbit plasma using ATR-FTIR combined with chemometrics: A preliminary study

NASA Astrophysics Data System (ADS)

Zhang, Ji; Li, Bing; Wang, Qi; Li, Chengzhi; Zhang, Yinming; Lin, Hancheng; Wang, Zhenyuan

2017-02-01

Postmortem interval (PMI) determination is one of the most challenging tasks in forensic medicine due to a lack of accurate and reliable methods. It is especially difficult for late PMI determination. Although many attempts with various types of body fluids based on chemical methods have been made to solve this problem, few investigations are focused on blood samples. In this study, we employed an attenuated total reflection (ATR)-Fourier transform infrared (FTIR) technique coupled with principle component analysis (PCA) to monitor biochemical changes in rabbit plasma with increasing PMI. Partial least square (PLS) model was used based on the spectral data for PMI prediction in an independent sample set. Our results revealed that postmortem chemical changes in compositions of the plasma were time-dependent, and various components including proteins, lipids and nucleic acids contributed to the discrimination of the samples at different time points. A satisfactory prediction within 48 h postmortem was performed by the combined PLS model with a good fitting between actual and predicted PMI of 0.984 and with an error of ± 1.92 h. In consideration of the simplicity and portability of ATR-FTIR, our preliminary study provides an experimental and theoretical basis for application of this technique in forensic practice.

Relationship between sudden natural death and abdominal fat evaluated on postmortem CT scans.

PubMed

Kaichi, Y; Sakane, H; Higashibori, H; Honda, Y; Tatsugami, F; Baba, Y; Iida, M; Awai, K

2017-06-01

This study examined the association between sudden natural death and abdominal fat using postmortem computed tomography (CT) scans. Postmortem CT images at the umbilical level of 241 subjects were used to measure abdominal areas of subcutaneous- and visceral fat, the rate of visceral fat and the waist circumference. Of the study subjects, 174 died of sudden natural death (130 men and 44 women), and 67 died of different causes (46 men and 21 women). All were between 40 and 75 years of age. Logistic regression analysis was performed to identify independent abdominal parameters associated with sudden natural death. By univariate analysis, the areas of subcutaneous and visceral fat were significantly larger in sudden natural death than who died of different causes (subcutaneous fat, odds ratio [OR] = 1.004, 95% confidence interval [CI] = 1.000-1.007, p  = 0.03; visceral fat, OR = 1.008, 95% CI = 1.003-1.013, p  < 0.01). Multivariate analysis showed that the area of visceral fat was an independent factor associated with the risk of sudden natural death (OR = 1.008, 95% CI = 1.002-1.015, p  = 0.02). Postmortem CT revealed that sudden natural death was related to abdominal fat deposits.

Treatments of tilapia (Oreochromis niloticus) using nitric oxide for quality improvement: Establishing a potential method for large-scale processing of farmed fish.

PubMed

Wang, Zi-Chao; Yan, Yuzhen; Su, Ping; Zhao, Mou-Ming; Xia, Ning; Chen, De-Wei

2018-07-01

To find a succedaneum of present methods for slaughtering tilapia, we have demonstrated the influence of nitric oxide (NO) (saturated NO solution) through euthanasia before slaughter on the animal welfare and muscle color of tilapia. The results suggested that NO euthanasia significantly improved the animal welfare and muscle color. Besides, the investigation of NO postmortem treatment on the muscle color and color stability of tilapia fillets suggested that NO postmortem treatment not only improved the muscle color and color stability but also prolonged the shelf-life of tilapia fillets during the refrigerated storage. To further investigate the effect of NO euthanasia on the quality of tilapia fillets and to estimate the safety of NO treatments (NO euthanasia and NO postmortem treatment) for the application of NO treatments in industrial manufacturing of tilapia and possibly of other fish species. NO euthanasia was adopted in this study following a simulated fish processing line. HbNO and MbNO values were measured to clarify the mechanism and process of NO euthanasia. The blood parameters, muscle pH, rigor index, drip loss and total volatile basic nitrogen (TVB-N) values were measured to evaluate the quality of the fillets obtained from NO euthanized tilapia. Besides, the nitrate (NO 3 - ) levels in the muscles after the refrigerated storage were detected to estimate the food safety of both NO euthanasia and NO postmortem treatment. Fillets obtained from the tilapia euthanized by NO showed a later reduction of muscle pH, a later onset of rigor mortis postmortem and less drip loss during the refrigerated storage than control. NO euthanasia caused less TVB-N than control and prolonged the shelf life of tilapia fillets. Moreover, the NO 3 - levels in the muscles of both NO euthanasia and NO postmortem treatment after the refrigerated storage were below the maximum permitted limit. Both the NO euthanasia and NO postmortem treatment are suitable for improving the quality of tilapia fillets and reducing the food safety threats, which may be valuable for industrial manufacturing of tilapia and may be applicable for other fish species. Copyright © 2018 Elsevier Inc. All rights reserved.

Best-practices approach to determination of blood alcohol concentration (BAC) at specific time points: Combination of ante-mortem alcohol pharmacokinetic modeling and post-mortem alcohol generation and transport considerations.

PubMed

Cowan, Dallas M; Maskrey, Joshua R; Fung, Ernest S; Woods, Tyler A; Stabryla, Lisa M; Scott, Paul K; Finley, Brent L

2016-07-01

Alcohol concentrations in biological matrices offer information regarding an individual's intoxication level at a given time. In forensic cases, the alcohol concentration in the blood (BAC) at the time of death is sometimes used interchangeably with the BAC measured post-mortem, without consideration for alcohol concentration changes in the body after death. However, post-mortem factors must be taken into account for accurate forensic determination of BAC prior to death to avoid incorrect conclusions. The main objective of this work was to describe best practices for relating ante-mortem and post-mortem alcohol concentrations, using a combination of modeling, empirical data and other qualitative considerations. The Widmark modeling approach is a best practices method for superimposing multiple alcohol doses ingested at various times with alcohol elimination rate adjustments based on individual body factors. We combined the selected ante-mortem model with a suggestion for an approach used to roughly estimate changes in BAC post-mortem, and then analyzed the available data on post-mortem alcohol production in human bodies and potential markers for alcohol production through decomposition and putrefaction. Hypothetical cases provide best practice approaches as an example for determining alcohol concentration in biological matrices ante-mortem, as well as potential issues encountered with quantitative post-mortem approaches. This study provides information for standardizing BAC determination in forensic toxicology, while minimizing real world case uncertainties. Copyright © 2016 Elsevier Inc. All rights reserved.

Forensic entomology investigations from Doctor Marcel Leclercq (1924-2008): a review of cases from 1969 to 2005.

PubMed

Dekeirsschieter, J; Frederickx, C; Verheggen, F J; Boxho, P; Haubruge, E

2013-09-01

Dr. Marcel Leclercq was a pioneer in the field of forensic entomology. He has provided his knowledge of insect biology to many forensic cases, and most of them have found the way to publication. Most of the articles he has written were focused on individual cases, and despite the abundance of entomoforensic investigations he conducted, no synthesis has been published. This article summarizes 36 yr of forensic entomological investigations in temperate Europe, mainly in Belgium. Dr. Leclercq's work includes 132 entomological cases involving 141 human corpses found in various death scenes. Under certain conditions, insect specimens found at death scene can provide information on when (postmortem interval estimation), where and how a person died. More or less 100 insect species associated with a dead body have been identified by Dr. Leclercq.

Comparison of premortem and postmortem estimates of plutonium deposited in the skeleton and liver of six individuals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sula, M.J.; Bihl, D.E.; Carbaugh, E.H.

1988-04-01

Assessment of organ burdens after internal exposures to radionuclides is often necessary to evaluate the health and regulatory implications of the exposure. The assessment of plutonium activity in skeleton and liver is usually estimated from measurements of plutonium excreted via urine. As part of the overall evaluation of internal dose assessment techniques, it is useful to compare the results of organ burden estimates made from evaluation of urinary excretion data with those made at death from tissue samples collected posthumously from the individual. Estimates of plutonium in the skeleton and liver, based on postmortem analysis of tissue samples for sixmore » individuals, were obtained from the US Transuranium Registry (USTR). Bioassay data and other radiation exposure information obtained from the individuals' files were used to estimate their skeleton and liver burdens at the times of their deaths, and these estimates were compared to those obtained through tissue analysis. 6 refs., 2 tabs.« less

Differential Nuclear and Mitochondrial DNA Preservation in Post-Mortem Teeth with Implications for Forensic and Ancient DNA Studies

PubMed Central

Higgins, Denice; Rohrlach, Adam B.; Kaidonis, John; Townsend, Grant; Austin, Jeremy J.

2015-01-01

Major advances in genetic analysis of skeletal remains have been made over the last decade, primarily due to improvements in post-DNA-extraction techniques. Despite this, a key challenge for DNA analysis of skeletal remains is the limited yield of DNA recovered from these poorly preserved samples. Enhanced DNA recovery by improved sampling and extraction techniques would allow further advancements. However, little is known about the post-mortem kinetics of DNA degradation and whether the rate of degradation varies between nuclear and mitochondrial DNA or across different skeletal tissues. This knowledge, along with information regarding ante-mortem DNA distribution within skeletal elements, would inform sampling protocols facilitating development of improved extraction processes. Here we present a combined genetic and histological examination of DNA content and rates of DNA degradation in the different tooth tissues of 150 human molars over short-medium post-mortem intervals. DNA was extracted from coronal dentine, root dentine, cementum and pulp of 114 teeth via a silica column method and the remaining 36 teeth were examined histologically. Real time quantification assays based on two nuclear DNA fragments (67 bp and 156 bp) and one mitochondrial DNA fragment (77 bp) showed nuclear and mitochondrial DNA degraded exponentially, but at different rates, depending on post-mortem interval and soil temperature. In contrast to previous studies, we identified differential survival of nuclear and mtDNA in different tooth tissues. Futhermore histological examination showed pulp and dentine were rapidly affected by loss of structural integrity, and pulp was completely destroyed in a relatively short time period. Conversely, cementum showed little structural change over the same time period. Finally, we confirm that targeted sampling of cementum from teeth buried for up to 16 months can provide a reliable source of nuclear DNA for STR-based genotyping using standard extraction methods, without the need for specialised equipment or large-volume demineralisation steps. PMID:25992635

Assessing various Infrared (IR) microscopic imaging techniques for post-mortem interval evaluation of human skeletal remains.

PubMed

Woess, Claudia; Unterberger, Seraphin Hubert; Roider, Clemens; Ritsch-Marte, Monika; Pemberger, Nadin; Cemper-Kiesslich, Jan; Hatzer-Grubwieser, Petra; Parson, Walther; Pallua, Johannes Dominikus

2017-01-01

Due to the influence of many environmental processes, a precise determination of the post-mortem interval (PMI) of skeletal remains is known to be very complicated. Although methods for the investigation of the PMI exist, there still remains much room for improvement. In this study the applicability of infrared (IR) microscopic imaging techniques such as reflection-, ATR- and Raman- microscopic imaging for the estimation of the PMI of human skeletal remains was tested. PMI specific features were identified and visualized by overlaying IR imaging data with morphological tissue structures obtained using light microscopy to differentiate between forensic and archaeological bone samples. ATR and reflection spectra revealed that a more prominent peak at 1042 cm-1 (an indicator for bone mineralization) was observable in archeological bone material when compared with forensic samples. Moreover, in the case of the archaeological bone material, a reduction in the levels of phospholipids, proteins, nucleic acid sugars, complex carbohydrates as well as amorphous or fully hydrated sugars was detectable at (reciprocal wavelengths/energies) between 3000 cm-1 to 2800 cm-1. Raman spectra illustrated a similar picture with less ν2PO43-at 450 cm-1 and ν4PO43- from 590 cm-1 to 584 cm-1, amide III at 1272 cm-1 and protein CH2 deformation at 1446 cm-1 in archeological bone material/samples/sources. A semi-quantitative determination of various distributions of biomolecules by chemi-maps of reflection- and ATR- methods revealed that there were less carbohydrates and complex carbohydrates as well as amorphous or fully hydrated sugars in archaeological samples compared with forensic bone samples. Raman- microscopic imaging data showed a reduction in B-type carbonate and protein α-helices after a PMI of 3 years. The calculated mineral content ratio and the organic to mineral ratio displayed that the mineral content ratio increases, while the organic to mineral ratio decreases with time. Cluster-analyses of data from Raman microscopic imaging reconstructed histo-anatomical features in comparison to the light microscopic image and finally, by application of principal component analyses (PCA), it was possible to see a clear distinction between forensic and archaeological bone samples. Hence, the spectral characterization of inorganic and organic compounds by the afore mentioned techniques, followed by analyses such as multivariate imaging analysis (MIAs) and principal component analyses (PCA), appear to be suitable for the post mortem interval (PMI) estimation of human skeletal remains.

Assessing various Infrared (IR) microscopic imaging techniques for post-mortem interval evaluation of human skeletal remains

PubMed Central

Roider, Clemens; Ritsch-Marte, Monika; Pemberger, Nadin; Cemper-Kiesslich, Jan; Hatzer-Grubwieser, Petra; Parson, Walther; Pallua, Johannes Dominikus

2017-01-01

Due to the influence of many environmental processes, a precise determination of the post-mortem interval (PMI) of skeletal remains is known to be very complicated. Although methods for the investigation of the PMI exist, there still remains much room for improvement. In this study the applicability of infrared (IR) microscopic imaging techniques such as reflection-, ATR- and Raman- microscopic imaging for the estimation of the PMI of human skeletal remains was tested. PMI specific features were identified and visualized by overlaying IR imaging data with morphological tissue structures obtained using light microscopy to differentiate between forensic and archaeological bone samples. ATR and reflection spectra revealed that a more prominent peak at 1042 cm-1 (an indicator for bone mineralization) was observable in archeological bone material when compared with forensic samples. Moreover, in the case of the archaeological bone material, a reduction in the levels of phospholipids, proteins, nucleic acid sugars, complex carbohydrates as well as amorphous or fully hydrated sugars was detectable at (reciprocal wavelengths/energies) between 3000 cm-1 to 2800 cm-1. Raman spectra illustrated a similar picture with less ν2PO43−at 450 cm-1 and ν4PO43− from 590 cm-1 to 584 cm-1, amide III at 1272 cm-1 and protein CH2 deformation at 1446 cm-1 in archeological bone material/samples/sources. A semi-quantitative determination of various distributions of biomolecules by chemi-maps of reflection- and ATR- methods revealed that there were less carbohydrates and complex carbohydrates as well as amorphous or fully hydrated sugars in archaeological samples compared with forensic bone samples. Raman- microscopic imaging data showed a reduction in B-type carbonate and protein α-helices after a PMI of 3 years. The calculated mineral content ratio and the organic to mineral ratio displayed that the mineral content ratio increases, while the organic to mineral ratio decreases with time. Cluster-analyses of data from Raman microscopic imaging reconstructed histo-anatomical features in comparison to the light microscopic image and finally, by application of principal component analyses (PCA), it was possible to see a clear distinction between forensic and archaeological bone samples. Hence, the spectral characterization of inorganic and organic compounds by the afore mentioned techniques, followed by analyses such as multivariate imaging analysis (MIAs) and principal component analyses (PCA), appear to be suitable for the post mortem interval (PMI) estimation of human skeletal remains. PMID:28334006

Changes in Vickers hardness during the decomposition of bone: Possibilities for forensic anthropology.

PubMed

Walden, Steven J; Evans, Sam L; Mulville, Jacqui

2017-01-01

The purpose of this study was to determine how the Vickers hardness (HV) of bone varies during soft tissue putrefaction. This has possible forensic applications, notably for determining the postmortem interval. Experimental porcine bone samples were decomposed in surface and burial deposition scenarios over a period of 6 months. Although the Vickers hardness varied widely, it was found that when transverse axial hardness was subtracted from longitudinal axial hardness, the difference showed correlations with three distinct phases of soft tissue putrefaction. The ratio of transverse axial hardness to longitudinal axial hardness showed a similar correlation. A difference of 10 or greater in HV with soft tissue present and signs of minimal decomposition, was associated with a decomposition period of 250 cumulative cooling degree days or less. A difference of 10 (+/- standard error of mean at a 95% confidence interval) or greater in HV associated with marked decomposition indicated a decomposition period of 1450 cumulative cooling degree days or more. A difference of -7 to +8 (+/- standard error of mean at a 95% confidence interval) was thus associated with 250 to 1450 cumulative cooling degree days' decomposition. The ratio of transverse axial HV to longitudinal HV, ranging from 2.42 to 1.54, is a more reliable indicator in this context and is preferable to using negative integers These differences may have potential as an indicator of postmortem interval and thus the time of body deposition in the forensic context. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Decomposition patterns of buried remains at different intervals in the Central Highveld region of South Africa.

PubMed

Marais-Werner, A; Myburgh, J; Meyer, A; Nienaber, W C; Steyn, M

2017-07-01

Burial of remains is an important factor when one attempts to establish the post-mortem interval as it reduces, and in extreme cases, excludes oviposition by Diptera species. This in turn leads to modification of the decomposition process. The aim of this study was to record decomposition patterns of buried remains using a pig model. The pattern of decomposition was evaluated at different intervals and recorded according to existing guidelines. In order to contribute to our knowledge on decomposition in different settings, a quantifiable approach was followed. Results indicated that early stages of decomposition occurred rapidly for buried remains within 7-33 days. Between 14 and 33 days, buried pigs displayed common features associated with the early to middle stages of decomposition, such as discoloration and bloating. From 33 to 90 days advanced decomposition manifested on the remains, and pigs then reached a stage of advanced decomposition where little change was observed in the next ±90-183 days after interment. Throughout this study, total body scores remained higher for surface remains. Overall, buried pigs followed a similar pattern of decomposition to those of surface remains, although at a much slower rate when compared with similar post-mortem intervals in surface remains. In this study, the decomposition patterns and rates of buried remains were mostly influenced by limited insect activity and adipocere formation which reduces the rate of decay in a conducive environment (i.e. burial in soil).

[Criteria for the classification as a "domestic-setting corpse"--a literature search and review to define the term].

PubMed

Merz, Marius; Birngruber, Christoph G; Heidorn, Frank; Ramsthaler, Frank; Risse, Manfred; Kreutz, Kerstin; Krähahn, Jonathan; Verhoff, Marcel A

2011-01-01

In German medical and media circles (daily routine, specialist literature, press, novels), the term "domestic-setting corpse" is frequently used, but the term is only vaguely defined. The authors thus decided to perform an in-depth study of the literature, including historic textbooks and all German- and English-language medicolegal journals, going as far back as their first issues, in an attempt to more clearly define the term. Inclusion criteria used in the search were a post-mortem interval of at least 24 hours prior to discovery and discovery of the corpse in a domestic setting. In the literature, 37 cases that complied with the above-mentioned inclusion criteria were found. These cases frequently described "advanced decomposition", often "unclear cause of death" and "problems in identification". These characteristics can thus be considered as being additional pointers in the definition. However, we suggest that the two general defining characteristics of a "domestic-setting corpse" are a post-mortem interval of more than 24 hours before discovery and the discovery of the corpse in a domestic setting.

Is flow cytometric evaluation of DNA degradation a reliable method to investigate the early postmortem period?

PubMed

Di Nunno, N R; Costantinides, F; Bernasconi, P; Bottin, C; Melato, M

1998-03-01

The time of death can be established by determining the length of the postmortem interval. Many methods have been proposed to achieve this goal. Flow cytometric evaluation of DNA degradation seems to be reliable for the first 72 hours after death. Our study evaluated the correspondence of the corruption process between in vitro and corpse tissues. We chose spleen tissue to perform our investigation because it is rich in nucleated cells. Results showed a precise correspondence between the two kinds of samples in the time period between 24 and 36 hours. The period from 36 to 72 hours is characterized by a much looser correspondence than that found in the first period. After the first 72 hours, DNA denaturation is massive and does not allow useful cytofluorimetric readings. The spleen does not seem to be the most suitable organ for this type of investigation because it tends to colliquate very rapidly. We therefore are evaluating other organs to identify a more suitable tissue source for the investigation of longer postmortem period using flow cytometry.

Gene expression in the twilight of death: The increase of thousands of transcripts has implications to transplantation, cancer, and forensic research.

PubMed

Pozhitkov, Alexander E; Noble, Peter A

2017-09-01

After a vertebrate dies, many of its organ systems, tissues, and cells remain functional while its body no longer works as a whole. We define this state as the "twilight of death" - the transition from a living body to a decomposed corpse. We claim that the study of the twilight of death is important to ethical, legal and medical science. We examined gene expression at the twilight of death in the zebrafish and mouse reaching the conclusion that apparently thousands of transcripts significantly increase in abundance from life to several hours/days postmortem relative to live controls. Transcript dynamics of different genes provided "proof-of-principle" that models accurately predict an individual's elapsed-time-of-death (i.e. postmortem interval). While many transcripts were associated with survival and stress compensation, others were associated with epigenetic factors, developmental control, and cancer. Future studies are needed to determine whether the high incidence of cancer in transplant recipients is due to the postmortem processes in donor organs. © 2017 WILEY Periodicals, Inc.

Forensic mycology: the use of fungi in criminal investigations.

PubMed

Hawksworth, David L; Wiltshire, Patricia E J

2011-03-20

This is the first overview to be published of the whole field of forensic mycology. It is based on all available information located in the literature, together with 13 examples from recent casework. Background information on fungi is given, and this is followed by an outline of the value, and potentially wide application, of mycology in criminal investigation. Applications include roles in: providing trace evidence; estimating time since death (post-mortem interval); ascertaining time of deposition; investigating cause of death, hallucinations, or poisonings; locating buried corpses; and biological warfare. Previous work has been critically evaluated, with particular attention to its evidential value, and suitability for presentation in a court of law. The situations where mycology might assist an investigation are summarised, and issues relating to the further development of the subject are presented. A comprehensive bibliography with 120 citations is provided. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Nocturnal colonization behavior of blowflies (Diptera: Calliphoridae) in southeastern Australia.

PubMed

George, Kelly A; Archer, Melanie S; Toop, Tes

2013-01-01

Worldwide research into nocturnal colonization by blowflies has produced many contradictory findings, prompting investigation specific to southeastern Australia. Initial experiments showed that blowfly colonization begins shortly after sunrise and continues until sunset; nocturnal colonization never occurred. Colonization peaks occurred at mid-morning, midday, and in the hours preceding sunset. In an additional experiment, wild blowflies were captured and placed in cages with colonization medium supplied nocturnally. Colonization occurred on four of five nights, and Calliphora augur (Fabricius) (Diptera: Calliphoridae) was the main species colonizing baits nocturnally. Results suggest that colonization is most likely to occur during warm weather and when flies are able to walk or crawl to bait. In particular, blowflies trapped within a confined space (such as a room or car) with warmer-than-ambient temperature may be stimulated to colonize nearby remains. Entomologists should consider these findings when estimating minimum postmortem interval under these environmental conditions. © 2012 American Academy of Forensic Sciences.

Analysis of the Effect of Cyclophosphamide and Methotrexate on Chrysomya megacephala (Diptera: Calliphoridae).

PubMed

Trivia, Ana Letícia; de Carvalho Pinto, Carlos José

2018-01-19

Forensic entomotoxicology investigates the effects of chemical substances in the development of scavenger insects and the reflection on estimating the minimum postmortem interval (PMI). To evaluate the impact of the chemotherapeutic drugs cyclophosphamide (CF) and methotrexate (MTX) on the postembryonic development of Chrysomya megacephala, controlled experiments were performed by rearing the larvae on spiked minced beef with different concentrations of these drugs. The results indicated that CF significantly decreased their developmental rate up to 28 h but had no significant effect on larval and adult sizes, survival rate, and sex ratio, whereas MTX decreased larval and adult sizes, survival rate, and there was a deviation in the expected sex ratio toward females in MTX-exposed larvae but had no significant impact on developmental rate. These negative interference factors should be considered in cases of suspected death of people that have undergone chemotherapy. © 2018 American Academy of Forensic Sciences.

Shells and Bones: A Forensic Medicine Study of the Association of Terrestrial Snail Allopeas micra with Buried Human Remains in Brazil.

PubMed

Galvão, Malthus Fonseca; Pujol-Luz, José Roberto; de Assis Pujol-Luz, Cristiane Vieira; de Rosa, Cássio Thyone Almeida; Simone, Luiz Ricardo L; Báo, Sônia Nair; Barros-Cordeiro, Karine Brenda; Pessoa, Larissa; Bissacot, Giovanna

2015-09-01

Little is known regarding the scavenger fauna associated with buried human corpses, particularly in clandestine burials. We report the presence of 20 shells of the terrestrial snail Allopeas micra, within hollow bones of human remains buried for 5 years, during the process of collecting DNA material. The fact that a large number of shells of A. micra had been found in the corpse and in the crime scene supports the assumption that there was no attempt to remove the corpse from the area where the crime occurred. Despite this, our observations cannot be used to estimate the postmortem interval because there is no precise knowledge about the development of this species. This is the first record of a terrestrial snail associated with a human corpse and its role in this forensic medicine case. © 2015 American Academy of Forensic Sciences.

Influence of resources on Hermetia illucens (Diptera: Stratiomyidae) larval development.

PubMed

Nguyen, Trinh T X; Tomberlin, Jeffery K; Vanlaerhoven, Sherah

2013-07-01

Arthropod development can be used to determine the time of colonization of human remains to infer a minimum postmortem interval. The black soldier fly, Hermetia illucens L. (Diptera. Stratiomyidae) is native to North America and is unique in that its larvae can consume a wide range of decomposing organic material, including carrion. Larvae development was observed on six resources: control poultry feed, liver, manure, kitchen waste, fruits and vegetables, and fish rendering. Larvae fed manure were shorter, weighed less, and took longer to develop. Kitchen waste produced longer and heavier larvae, whereas larvae fed fish had almost 100% mortality. Black soldier flies can colonize human remains, which in many instances can coincide with food and organic wastes. Therefore, it is necessary to understand black soldier fly development on different food resources other than carrion tissue to properly estimate their age when recovered from human remains.

Postmortem redistribution of Δ9-tetrahydrocannabinol (THC), 11-hydroxy-THC (11-OH-THC), and 11-nor-9-carboxy-THC (THCCOOH)

PubMed Central

Holland, Michael G.; Schwope, David M.; Stoppacher, Robert; Gillen, Shane B.; Huestis, Marilyn A.

2012-01-01

Introduction Postmortem redistribution (PMR), a well-described phenomenon in forensic toxicology for certain drugs, can result in increased central blood concentrations relative to peripheral blood concentrations. Δ9-tetrahydrocannabinol (THC), the primary psychoactive component in cannabis or marijuana, is the illicit substance most commonly implicated in driving under the influence of drugs (DUID) cases and fatally-injured drivers. No investigation of PMR of THC in human blood has been reported to date. Methods Matched heart and iliac postmortem blood specimens were collected from 19 medical examiner cases (16 Males, 3 Females) with positive cannabinoid urine immunoassay screens. THC, its equipotent metabolite 11-hydroxy-THC (11-OH-THC) and non-psychoactive metabolite 11-nor-9-carboxy-THC (THCCOOH) were quantified by two-dimensional gas chromatography-mass spectrometry with cryofocusing, with 0.5 ng/mL limits of quantification (LOQ) for all analytes. Results 10 cases had quantifiable THC and 11-OH-THC; THCCOOH was present in all 19. Median (range) heart:iliac blood ratios were 1.5 for THC (range: 0.3–3.1); 1.6 for 11-OH-THC (range: 0.3–2.7); and 1.8 for THCCOOH (range: 0.5–3.0). Discussion Cannabinoids, in general, exhibited a mean and median central: peripheral (C: P) concentration ratio of less than 2 following death. A trend was observed for greater PMR with increasing postmortem interval between death and sampling. To our knowledge, these are the first data on THC PMR in humans, providing important scientific data to aid in the interpretation of postmortem cannabinoid concentrations in medico-legal investigations. PMID:21764230

Post-mortem chemical excitability of the iris should not be used for forensic death time diagnosis.

PubMed

Koehler, Katja; Sehner, Susanne; Riemer, Martin; Gehl, Axel; Raupach, Tobias; Anders, Sven

2018-04-18

Post-mortem chemical excitability of the iris is one of the non-temperature-based methods in forensic diagnosis of the time since death. Although several authors reported on their findings, using different measurement methods, currently used time limits are based on a single dissertation which has recently been doubted to be applicable for forensic purpose. We investigated changes in pupil-iris ratio after application of acetylcholine (n = 79) or tropicamide (n = 58) and in controls at upper and lower time limits that are suggested in the current literature, using a digital photography-based measurement method with excellent reliability. We observed "positive," "negative," and "paradox" reactions in both intervention and control conditions at all investigated post-mortem time points, suggesting spontaneous changes in pupil size to be causative for the finding. According to our observations, post-mortem chemical excitability of the iris should not be used in forensic death time estimation, as results may cause false conclusions regarding the correct time point of death and might therefore be strongly misleading.

Gamete rescue in the African black rhinoceros (Diceros bicornis).

PubMed

Stoops, M A; O'Brien, J K; Roth, T L

2011-10-15

Mortality rates are high among captive African black rhinoceroses (Diceros bicornis), due to increased susceptibility to disease. The ability to rescue genetic material from individuals that die unexpectedly represents a practical approach to assist ex situ conservation efforts. The objectives of the present study were to attempt postmortem oocyte recovery from ovaries of African black rhinoceroses (N = 6) and to test the efficacy of equine protocols for rhinoceros oocyte IVM and IVF using cryopreserved rhinoceros sperm. The interval from ovary removal to oocyte recovery was 25.3 ± 13.9 h (mean ± SD). Ovaries were transported at 4 °C or 22 °C and effects of temperature on postmortem oocyte competence was evaluated. Numbers of oocytes collected per female averaged 15.8 ± 6.9. In total, 95 oocytes were recovered. Of these, 85 were inseminated using homologous sperm and 10 were inseminated using heterologous sperm. Overall, substantial numbers of viable oocytes were retrieved from African black rhinoceros ovaries 1 to 2 days postmortem from ovaries stored at ambient temperature. A proportion of these oocytes matured and underwent penetration and fertilization by heterologous or homologous frozen-thawed rhinoceros sperm. The reproductive competence of postmortem oocytes was further demonstrated by development of a single two-cell embryo. Despite the need for further refinements, gamete rescue in the rhinoceros has promise for producing rhinoceros embryos, as well as testing sperm functions in vitro. Copyright © 2011 Elsevier Inc. All rights reserved.

Vitreous humor analysis for the detection of xenobiotics in forensic toxicology: a review.

PubMed

Bévalot, Fabien; Cartiser, Nathalie; Bottinelli, Charline; Fanton, Laurent; Guitton, Jérôme

2016-01-01

Vitreous humor (VH) is a gelatinous substance contained in the posterior chamber of the eye, playing a mechanical role in the eyeball. It has been the subject of numerous studies in various forensic applications, primarily for the assessment of postmortem interval and for postmortem chemical analysis. Since most of the xenobiotics present in the bloodstream are detected in VH after crossing the selective blood-retinal barrier, VH is an alternative matrix useful for forensic toxicology. VH analysis offers particular advantages over other biological matrices: it is less prone to postmortem redistribution, is easy to collect, has relatively few interfering compounds for the analytical process, and shows sample stability over time after death. The present study is an overview of VH physiology, drug transport and elimination. Collection, storage, analytical techniques and interpretation of results from qualitative and quantitative points of view are dealt with. The distribution of xenobiotics in VH samples is thus discussed and illustrated by a table reporting the concentrations of 106 drugs from more than 300 case reports. For this purpose, a survey was conducted of publications found in the MEDLINE database from 1969 through April 30, 2015.

Taenia spp. infections in wildlife in the Bangweulu and Kafue flood plains ecosystems of Zambia.

PubMed

Muma, J B; Gabriël, S; Munyeme, M; Munang'andu, H M; Victor, B; Dorny, P; Nalubamba, K S; Siamudaala, V; Mwape, K E

2014-09-15

Taenia spp. have an indirect life cycle, cycling between a definitive and an intermediate host with zoonotic species causing public health problems in many developing countries. During the course of 2 separate surveys in Zambia (2004 and 2009), the presence of Taenia larval stages (cysticerci) was examined in Kafue lechwe (Kobus leche kafuensis), Black lechwe (Kobus leche smithermani) and other wildlife species from the Kafue and Bangweulu flood plains. Examinations involved post-mortem inspection and serum specific antigen detection. The recovered cysts from seven carcasses were characterised using PCR and DNA sequence analysis. The overall proportion of infection in wildlife on post-mortem examination was 19.0% (95% CI: 9.1-29.0%). The proportion of infected wildlife based on post-mortem examinations in the Kafue flood plains was estimated at 28.6% (95% CI: 13.3-43.9%), while the seroprevalence was estimated at 25.0% (95% CI: 2.9-47.1%). The seroprevalence for cattle in the Kafue flood plains was estimated at 61.5% (95% CI: 42.0-81.0%) while that of Kafue lechwe in the same ecosystem was estimated at 66.6% (95% CI: 45.6-85.7%). Infection rates were higher in Kafue lechwe than in Black lechwe suggesting differences in the exposure patterns. The sequencing results indicated that none of the recovered cysts were either Taenia solium or Taenia saginata. We therefore conclude they most likely belong to a less studied (wildlife) Taenia species that requires further characterisation. Copyright © 2014 Elsevier B.V. All rights reserved.

Forensic Entomology in Animal Cruelty Cases.

PubMed

Brundage, A; Byrd, J H

2016-09-01

Forensic entomology can be useful to the veterinary professional in cases of animal cruelty. A main application of forensic entomology is to determine the minimum postmortem interval by estimating the time of insect colonization, based on knowledge of the rate of development of pioneer colonizers and on insect species succession during decomposition of animal remains. Since insect development is temperature dependent, these estimates require documentation of the environmental conditions, including ambient temperature. It can also aid in the detection and recognition of wounds, as well as estimate the timing of periods of neglect. Knowledge of the geographic distribution of insects that colonize animal remains may suggest that there has been movement or concealment of the carcass or can create associations between a suspect, a victim, and a crime scene. In some instances, it can aid in the detection of drugs or toxins within decomposed or skeletonized remains. During animal cruelty investigations, it may become the responsibility of the veterinary professional to document and collect entomological evidence from live animals or during the necropsy. The applications of forensic entomology are discussed. A protocol is described for documenting and collecting entomological evidence at the scene and during the necropsy, with additional emphasis on recording geographic location, meteorological data, and collection and preservation of insect specimens. © The Author(s) 2016.

Life history data on the fly parasitoids Aleochara nigra Kraatz and A. asiatica Kraatz (Coleoptera: Staphylinidae), and their potential application in forensic entomology.

PubMed

Lin, Shou-Wang; Shiao, Shiuh-Feng

2013-10-10

Knowledge of the developmental time of the immature stages of necrophagous flies has been the main tool for estimating minimum post-mortem intervals (min PMIs) in forensic entomology. Many parasitic insects can alter the development of immature stages of flies and thus affect min PMI estimates. The larvae of most species of Aleochara rove beetles are ectoparasitoids of the pupae of cyclorrhapha flies. Among them, some species that parasitise necrophagous flies may have forensic importance. Two Taiwanese Aleochara species, A. nigra and A. asiatica, which visit carrion sites were studied herein. All five necrophagous (Hemipyrellia ligurriens, Lucilia cuprina, Chrysomya megacephala, C. rufifacies and sarcophagid sp.) and one non-necrophagous fly species (Bactrocera dorsalis) we examined have the potential to be parasitised by these two Aleochara species, but differences among the acceptability and suitability of these hosts to rove beetle species suggested that rove beetles may prefer specific hosts. Each stage of the beetle life history was recorded to estimate developmental durations at six different temperatures. The larval stage together with the pupal stage of both beetle species was longer than the pupal stages of their hosts, implying the possibility of elongating the min PMI estimation. In addition, the host weight and larval duration of these two Aleochara beetles were positively correlated; thus, potential applications can be expected when using parasitised fly pupae in min PMI estimations. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Are animal models predictive for human postmortem muscle protein degradation?

PubMed

Ehrenfellner, Bianca; Zissler, Angela; Steinbacher, Peter; Monticelli, Fabio C; Pittner, Stefan

2017-11-01

A most precise determination of the postmortem interval (PMI) is a crucial aspect in forensic casework. Although there are diverse approaches available to date, the high heterogeneity of cases together with the respective postmortal changes often limit the validity and sufficiency of many methods. Recently, a novel approach for time since death estimation by the analysis of postmortal changes of muscle proteins was proposed. It is however necessary to improve the reliability and accuracy, especially by analysis of possible influencing factors on protein degradation. This is ideally investigated on standardized animal models that, however, require legitimization by a comparison of human and animal tissue, and in this specific case of protein degradation profiles. Only if protein degradation events occur in comparable fashion within different species, respective findings can sufficiently be transferred from the animal model to application in humans. Therefor samples from two frequently used animal models (mouse and pig), as well as forensic cases with representative protein profiles of highly differing PMIs were analyzed. Despite physical and physiological differences between species, western blot analysis revealed similar patterns in most of the investigated proteins. Even most degradation events occurred in comparable fashion. In some other aspects, however, human and animal profiles depicted distinct differences. The results of this experimental series clearly indicate the huge importance of comparative studies, whenever animal models are considered. Although animal models could be shown to reflect the basic principles of protein degradation processes in humans, we also gained insight in the difficulties and limitations of the applicability of the developed methodology in different mammalian species regarding protein specificity and methodic functionality.

Locus Coeruleus Neuron Density and Parkinsonism in Older Adults without Parkinson’s Disease

PubMed Central

Buchman, Aron S.; Nag, Sukriti; Shulman, Joshua M.; Lim, Andrew S.P.; VanderHorst, Veronique G.J.M.; Leurgans, Sue E.; Schneider, Julie A.; Bennett, David A.

2013-01-01

Objective Prior work has showed that nigral neuron density is related to the severity of parkinsonism proximate to death in older persons without a clinical diagnosis of Parkinson’s disease (PD). We tested the hypothesis that neuron density in other brainstem aminergic nuclei is also related to the severity of parkinsonism. Design We studied brain autopsies from 125 deceased older adults without PD enrolled in the Memory and Aging Project, a clinical-pathologic investigation. Parkinsonism was assessed with a modified version of the Unified Parkinson’s Disease Rating Scale (UPDRS). We measured neuron density in the substantia nigra, ventral tegmental area, locus coeruleus and dorsal raphe; and postmortem indices of Lewy body Alzheimer’s disease and cerebrovascular pathologies. Results Mean age at death was 88.0 and global parkinsonism was 14.8 (SD=9.50). In a series of regression models which controlled for demographics and neuron density in the substantia nigra, neuron density in the locus coeruleus (Estimate, −0.261, S.E., 0.117, p=0.028) but not in the ventral tegmental area or dorsal raphe was associated with the severity of global parkinsonism proximate to death. These findings were unchanged in models which controlled for post-mortem interval, whole brain weight and other common neuropathologies including Alzheimer’s disease and Lewy body pathology and cerebrovascular vascular pathologies. Conclusion In older adults without a clinical diagnosis of PD, neuron density in locus coeruleus nuclei is associated with the severity of parkinsonism and may contribute to late-life motor impairments. PMID:23038629

Quantitative Susceptibility Mapping by Inversion of a Perturbation Field Model: Correlation with Brain Iron in Normal Aging

PubMed Central

Poynton, Clare; Jenkinson, Mark; Adalsteinsson, Elfar; Sullivan, Edith V.; Pfefferbaum, Adolf; Wells, William

2015-01-01

There is increasing evidence that iron deposition occurs in specific regions of the brain in normal aging and neurodegenerative disorders such as Parkinson's, Huntington's, and Alzheimer's disease. Iron deposition changes the magnetic susceptibility of tissue, which alters the MR signal phase, and allows estimation of susceptibility differences using quantitative susceptibility mapping (QSM). We present a method for quantifying susceptibility by inversion of a perturbation model, or ‘QSIP’. The perturbation model relates phase to susceptibility using a kernel calculated in the spatial domain, in contrast to previous Fourier-based techniques. A tissue/air susceptibility atlas is used to estimate B0 inhomogeneity. QSIP estimates in young and elderly subjects are compared to postmortem iron estimates, maps of the Field-Dependent Relaxation Rate Increase (FDRI), and the L1-QSM method. Results for both groups showed excellent agreement with published postmortem data and in-vivo FDRI: statistically significant Spearman correlations ranging from Rho = 0.905 to Rho = 1.00 were obtained. QSIP also showed improvement over FDRI and L1-QSM: reduced variance in susceptibility estimates and statistically significant group differences were detected in striatal and brainstem nuclei, consistent with age-dependent iron accumulation in these regions. PMID:25248179

Postmortem 31P magnetic resonance spectroscopy of the skeletal muscle: α-ATP/Pi ratio as a forensic tool?

PubMed

Schmidt, Tony M; Wang, Zhiyue J; Keller, Sarah; Heinemann, Axel; Acar, Suzan; Graessner, Joachim; Schoennagel, Bjoern P; Adam, Gerhard; Fischer, Roland; Yamamura, Jin

2014-09-01

Phosphor magnetic resonance spectroscopy ((31)P MRS) is an established method for metabolic examinations of resting and exercising skeletal muscle. So far, there are few MRS investigations of human corpses. The aim of this study was to investigate the temporal postmortem pattern of phosphor metabolites in the adductor magnus muscle and to check the value of MRS as a forensic tool, especially for the determination of the time of death. Eight corpses, died of natural cause, were examined (5 males, 3 females; age: 73±7 y, weight 65.8±15.9 kg). A control group of 3 subjects (2 males, 1 female, mean age: 51±24 y, range: 24-69 y, mean body weight: 84.0±16.5 kg) was examined at a single time point as well. (31)P MRS was performed on a 1.5 T MRI (TR 700 ms, TE 0.35 ms, averages 256, flip angle 90°). A standard (31)P/(1)H heart/liver coil was employed (receiver coil diameter 12 cm). The (31)P MRS scans were repeated in intervals of 1 h over a period from 4.5 to 24 h postmortem (p.m.). The core temperature was rectally measured throughout the MRI examination. The mean core temperature decreased from 36.0°C to 25.7°C. In vivo and ex vivo spectra showed characteristic differences, especially the PCr metabolite was no longer detectable after 10 h p.m. The α-ATP/Pi ratio decreased with time from 0.445 to 0.032 over 24 h p.m. There is a characteristic postmortem time pattern of the phosphor metabolites. Especially the acquired α-ATP/Pi ratio could be described by a significant exponential time course (r(2)=0.92, p<0.001). (31)P MRS might be added to the postmortem imaging methods. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Ex-vivo quantitative susceptibility mapping of human brain hemispheres

PubMed Central

Kotrotsou, Aikaterini; Tamhane, Ashish A.; Dawe, Robert J.; Kapasi, Alifiya; Leurgans, Sue E.; Schneider, Julie A.; Bennett, David A.; Arfanakis, Konstantinos

2017-01-01

Ex-vivo brain quantitative susceptibility mapping (QSM) allows investigation of brain characteristics at essentially the same point in time as histopathologic examination, and therefore has the potential to become an important tool for determining the role of QSM as a diagnostic and monitoring tool of age-related neuropathologies. In order to be able to translate the ex-vivo QSM findings to in-vivo, it is crucial to understand the effects of death and chemical fixation on brain magnetic susceptibility measurements collected ex-vivo. Thus, the objective of this work was twofold: a) to assess the behavior of magnetic susceptibility in both gray and white matter of human brain hemispheres as a function of time postmortem, and b) to establish the relationship between in-vivo and ex-vivo gray matter susceptibility measurements on the same hemispheres. Five brain hemispheres from community-dwelling older adults were imaged ex-vivo with QSM on a weekly basis for six weeks postmortem, and the longitudinal behavior of ex-vivo magnetic susceptibility in both gray and white matter was assessed. The relationship between in-vivo and ex-vivo gray matter susceptibility measurements was investigated using QSM data from eleven older adults imaged both antemortem and postmortem. No systematic change in ex-vivo magnetic susceptibility of gray or white matter was observed over time postmortem. Additionally, it was demonstrated that, gray matter magnetic susceptibility measured ex-vivo may be well modeled as a linear function of susceptibility measured in-vivo. In conclusion, magnetic susceptibility in gray and white matter measured ex-vivo with QSM does not systematically change in the first six weeks after death. This information is important for future cross-sectional ex-vivo QSM studies of hemispheres imaged at different postmortem intervals. Furthermore, the linear relationship between in-vivo and ex-vivo gray matter magnetic susceptibility suggests that ex-vivo QSM captures information linked to antemortem gray matter magnetic susceptibility, which is important for translation of ex-vivo QSM findings to in-vivo. PMID:29261693

Algor mortis: an erroneous measurement following postmortem refrigeration.

PubMed

Wardak, Khalil S; Cina, Stephen J

2011-09-01

Determination of the time of death is one goal of medicolegal death investigations. Algor mortis has been used as a measure of the postmortem interval (PMI). We prospectively recorded the core temperatures of 19 adult bodies entering our morgue cooler and at 3, 6, and 9 h of refrigeration. We then compared the cooling rate with the calculated body mass index (BMI). For each individual body, the rate of cooling was fairly linear with no evidence of a plateau. There was fair to moderate correlation between the BMI and the cooling rate: cooling rate = -0.052 (BMI) + 3.52. The probability of linearity in any given case was 36%. Variables affecting this correlation included the presence and the layers of clothing and if the clothing was wet. Our data confirm that algor mortis is of very limited utility in determining the PMI in bodies that have been refrigerated. © 2011 American Academy of Forensic Sciences.

Forensic implication of muscle level of nicotine in an adipocere body found in the sea.

PubMed

Nishimura, Hiroyuki; Furumiya, Junichi; Nakanishi, Akinori; Hashimoto, Yoshiaki

2009-04-01

We reported previously that blood levels of nicotine in suicidal smokers tend to be significantly higher than those in non-suicidal smokers, and blood level of nicotine seems to be a useful criterion for discriminating suicide from other types of death. In this paper, we report nicotine and cotinine levels in various tissues of an adipocere body found in the sea. The cause of death was drowning, and the postmortem time interval was approximately 5 months at autopsy. His driver's license was concealed in his sock, which seemed to suggest that he committed to suicide. In toxicological analysis by gas chromatography, nicotine and cotinine in the femoral muscle were detected at concentrations of 213 and 488 ng/g, respectively, and these substances were also detected in the brain, liver and kidney. For evaluating the tissue levels of nicotine and cotinine in the adipocere body, we analyzed these levels in blood and various tissues of 13 autopsy cases of smokers. Nicotine and cotinine levels in blood were the most similar to those in skeletal muscle. Although the postmortem time interval, the formation process of adipocere and the environmental condition in water may affect nicotine and cotinine levels in the femoral muscle, the high muscle level of nicotine in the present case seem to implicate suicidal death.

The Effect of Body Mass on Outdoor Adult Human Decomposition.

PubMed

Roberts, Lindsey G; Spencer, Jessica R; Dabbs, Gretchen R

2017-09-01

Forensic taphonomy explores factors impacting human decomposition. This study investigated the effect of body mass on the rate and pattern of adult human decomposition. Nine males and three females aged 49-95 years ranging in mass from 73 to 159 kg who were donated to the Complex for Forensic Anthropology Research between December 2012 and September 2015 were included in this study. Kelvin accumulated degree days (KADD) were used to assess the thermal energy required for subjects to reach several total body score (TBS) thresholds: early decomposition (TBS ≥6.0), TBS ≥12.5, advanced decomposition (TBS ≥19.0), TBS ≥23.0, and skeletonization (TBS ≥27.0). Results indicate no significant correlation between body mass and KADD at any TBS threshold. Body mass accounted for up to 24.0% of variation in decomposition rate depending on stage, and minor differences in decomposition pattern were observed. Body mass likely has a minimal impact on postmortem interval estimation. © 2017 American Academy of Forensic Sciences.

Investigation of nocturnal oviposition by necrophilous flies in central Texas.

PubMed

Baldridge, Robert S; Wallace, Susan G; Kirkpatrick, Ryan

2006-01-01

The need to accurately estimate the postmortem interval (PMI) has prompted research into factors affecting fly oviposition (i.e., oviposition and/or larviposition) on a corpse. Research efforts have focused on whether or not diurnally active flies oviposit during nighttime hours. This study reports that nocturnal oviposition (defined as occurring between 2100-0600 h CDST (Central Daylight Savings Time)) did not occur on freshly killed white rats or mice, on beef (fresh or aged up to 48 h), on freshly thawed pigs, nor, usually, on thawed pigs that were aged for up to 48 h. Limited oviposition did occur between 2100 and 2120 h on one bloated pig at a lighted rural site. Necrophilous flies were present and active at lighted and dark sites (urban and rural) before and immediately after sunset, but fly activity on the bait ceased within 50 min postsunset and did not resume until after 0600 h. These observations support other studies reporting that diurnally active flies do not oviposit during the nighttime.

Development of the oriental latrine fly, Chrysomya megacephala (Diptera: Calliphoridae), at five constant temperatures

USGS Publications Warehouse

Gruner, S. V.; Slone, D.H.; Capinera, J.L.; Turco, M. P.

2017-01-01

Chrysomya megacephala (Fabricius) is a forensically important fly that is found throughout the tropics and subtropics. We calculated the accumulated development time and transition points for each life stage from eclosion to adult emergence at five constant temperatures: 15, 20, 25, 30, and 35 °C. For each transition, the 10th, 50th, and 90th percentiles were calculated with a logistic linear model. The mean transition times and % survivorship were determined directly from the raw laboratory data. Development times of C. megacephala were compared with that of two other closely related species, Chrysomya rufifacies (Macquart) and Phormia regina (Meigen). Ambient and larval mass temperatures were collected from field studies conducted from 2001–2004. Field study data indicated that adult fly activity was reduced at lower ambient temperatures, but once a larval mass was established, heat generation occurred. These development times and durations can be used for estimation of a postmortem interval (PMI).

Fly pupae and puparia as potential contaminants of forensic entomology samples from sites of body discovery.

PubMed

Archer, M S; Elgar, M A; Briggs, C A; Ranson, D L

2006-11-01

Fly pupae and puparia may contaminate forensic entomology samples at death scenes if they have originated not from human remains but from animal carcasses or other decomposing organic material. These contaminants may erroneously lengthen post-mortem interval estimates if no pupae or puparia are genuinely associated with the body. Three forensic entomology case studies are presented, in which contamination either occurred or was suspected. In the first case, blow fly puparia collected near the body were detected as contaminants because the species was inactive both when the body was found and when the deceased was last sighted reliably. The second case illustrates that contamination may be suspected at particularly squalid death scenes because of the likely presence of carcasses or organic material. The third case involves the presence at the body discovery site of numerous potentially contaminating animal carcasses. Soil samples were taken along transects to show that pupae and puparia were clustered around their probable sources.

The First Survey of Forensically Important Entomofauna Collected from Medicolegal Autopsies in South Korea

PubMed Central

Shin, Sang Eon; Lee, Hyun Ju; Park, Ji Hye; Ko, Kwang Soo; Kim, Yu-Hoon; Kim, Kyung Ryoul

2015-01-01

Forensic entomology applies insect evidence to legal problems such as the estimation of minimum postmortem interval (mPMI). For this purpose, knowledge of the insect fauna that are attracted to human cadavers in each geographic region is a prerequisite. Despite many studies investigating the insect fauna attracted to meat, there has been no survey of the entomofauna on human cadavers in the East Asian temperate climate zone, particularly in Korea. Therefore, this study reports the entomofauna collected from medicolegal autopsies in northeastern Seoul and its suburbs. Insect samples were collected from 35 medicolegal autopsies in 2010, 2011, and 2013. Molecular and morphological methods were utilized for taxonomic identification. Among 1398 individual samples belonging to 3 orders, 13 families, 18 genera, and 32 species, the dominant family and species were Calliphoridae and Lucilia sericata, respectively. Despite its limited scale, this study provides a snapshot of the general entomofauna that are attracted to human cadavers in this region. PMID:26185759

The detection of African horse sickness virus antigens and antibodies in young Equidae.

PubMed Central

Hamblin, C.; Anderson, E. C.; Mellor, P. S.; Graham, S. D.; Mertens, P. P.; Burroughs, J. N.

1992-01-01

Four ponies were each inoculated with a different serotype of African horse sickness virus (AHSV) which had been passaged through cell culture in order to achieve attenuation. Three of the ponies died suddenly after showing mild clinical signs, the fourth pony remained clinically normal and was killed at day 38. Infectious AHSV was isolated from blood samples collected at intervals from all four ponies. Positive antigen ELISA reactions were only observed with blood samples from two of the ponies on the two days preceding death. Specific AHSV antibodies were detected by ELISA in serum samples from the other two ponies although one eventually died. African horse sickness viral antigens were detected by ELISA in post-mortem tissue samples collected from all four ponies. No infectious virus could be detected in tissue samples taken post-mortem from the pony which survived African horse sickness (AHS) infection. In the event of a suspected outbreak of AHS it is recommended that sera and heparinized blood should be tested for specific antibodies and AHSV antigen respectively. When available, post-mortem tissues, including spleen, heart, lung and liver, should also be tested for AHSV antigen. Although the ELISA used for the detection of AHSV antigen is highly sensitive and specific, negative ELISA results should be confirmed by virus isolation attempts. PMID:1547837

Translational Research in Pediatrics IV: Solid Tissue Collection and Processing.

PubMed

Gillio-Meina, Carolina; Zielke, H Ronald; Fraser, Douglas D

2016-01-01

Solid tissues are critical for child-health research. Specimens are commonly obtained at the time of biopsy/surgery or postmortem. Research tissues can also be obtained at the time of organ retrieval for donation or from tissue that would otherwise have been discarded. Navigating the ethics of solid tissue collection from children is challenging, and optimal handling practices are imperative to maximize tissue quality. Fresh biopsy/surgical specimens can be affected by a variety of factors, including age, gender, BMI, relative humidity, freeze/thaw steps, and tissue fixation solutions. Postmortem tissues are also vulnerable to agonal factors, body storage temperature, and postmortem intervals. Nonoptimal tissue handling practices result in nucleotide degradation, decreased protein stability, artificial posttranslational protein modifications, and altered lipid concentrations. Tissue pH and tryptophan levels are 2 methods to judge the quality of solid tissue collected for research purposes; however, the RNA integrity number, together with analyses of housekeeping genes, is the new standard. A comprehensive clinical data set accompanying all tissue samples is imperative. In this review, we examined: the ethical standards relating to solid tissue procurement from children; potential sources of solid tissues; optimal practices for solid tissue processing, handling, and storage; and reliable markers of solid tissue quality. Copyright © 2016 by the American Academy of Pediatrics.

Selective localization of oxytocin receptors and vasopressin 1a receptors in the human brainstem

PubMed Central

Freeman, Sara M.; Smith, Aaron L.; Goodman, Mark M.; Bales, Karen L.

2017-01-01

Intranasal oxytocin affects a suite of human social behaviors, including trust, eye contact, and emotion recognition. However, it is unclear where oxytocin receptors (OXTR) and the structurally related vasopressin 1a receptors (AVPR1a) are expressed in the human brain. We have previously described a reliable, pharmacologically informed receptor autoradiography protocol for visualizing these receptors in postmortem primate brain tissue. We used this technique in human brainstem tissue to identify the neural targets of oxytocin and vasopressin. To determine binding selectivity of the OXTR radioligand and AVPR1a radioligand, sections were incubated in four conditions: radioligand alone, radioligand with the selective AVPR1a competitor SR49059, and radioligand with a low or high concentration of the selective OXTR competitor ALS-II-69. We found selective OXTR binding in the spinal trigeminal nucleus, a conserved region of OXTR expression in all primate species investigated to date. We found selective AVPR1a binding in the nucleus prepositus, an area implicated in eye gaze stabilization. The tissue's postmortem interval was not correlated with either the specific or nonspecific binding of either radioligand, indicating that it will not likely be a factor in similar postmortem studies. This study provides critical data for future studies of OXTR and AVPR1a in human brain tissue. PMID:26911439

Estimation of the time since death--reconsidering the re-establishment of rigor mortis.

PubMed

Anders, Sven; Kunz, Michaela; Gehl, Axel; Sehner, Susanne; Raupach, Tobias; Beck-Bornholdt, Hans-Peter

2013-01-01

In forensic medicine, there is an undefined data background for the phenomenon of re-establishment of rigor mortis after mechanical loosening, a method used in establishing time since death in forensic casework that is thought to occur up to 8 h post-mortem. Nevertheless, the method is widely described in textbooks on forensic medicine. We examined 314 joints (elbow and knee) of 79 deceased at defined time points up to 21 h post-mortem (hpm). Data were analysed using a random intercept model. Here, we show that re-establishment occurred in 38.5% of joints at 7.5 to 19 hpm. Therefore, the maximum time span for the re-establishment of rigor mortis appears to be 2.5-fold longer than thought so far. These findings have major impact on the estimation of time since death in forensic casework.

Postmortem validation of breast density using dual-energy mammography

PubMed Central

Molloi, Sabee; Ducote, Justin L.; Ding, Huanjun; Feig, Stephen A.

2014-01-01

Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dual energy mammography system. Glandular and adipose equivalent phantoms of uniform thickness were used to calibrate a dual energy basis decomposition algorithm. Dual energy decomposition was applied after scatter correction to calculate breast density. Breast density was also estimated using radiologist reader assessment, standard histogram thresholding and a fuzzy C-mean algorithm. Chemical analysis was used as the reference standard to assess the accuracy of different techniques to measure breast composition. Results: Breast density measurements using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean algorithm, and dual energy were in good agreement with the measured fibroglandular volume fraction using chemical analysis. The standard error estimates using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean, and dual energy were 9.9%, 8.6%, 7.2%, and 4.7%, respectively. Conclusions: The results indicate that dual energy mammography can be used to accurately measure breast density. The variability in breast density estimation using dual energy mammography was lower than reader assessment rankings, standard histogram thresholding, and fuzzy C-mean algorithm. Improved quantification of breast density is expected to further enhance its utility as a risk factor for breast cancer. PMID:25086548

Postmortem validation of breast density using dual-energy mammography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Molloi, Sabee, E-mail: symolloi@uci.edu; Ducote, Justin L.; Ding, Huanjun

2014-08-15

Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dual energy mammography system. Glandular and adipose equivalent phantoms of uniform thickness were used to calibrate a dual energy basis decomposition algorithm. Dual energy decompositionmore » was applied after scatter correction to calculate breast density. Breast density was also estimated using radiologist reader assessment, standard histogram thresholding and a fuzzy C-mean algorithm. Chemical analysis was used as the reference standard to assess the accuracy of different techniques to measure breast composition. Results: Breast density measurements using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean algorithm, and dual energy were in good agreement with the measured fibroglandular volume fraction using chemical analysis. The standard error estimates using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean, and dual energy were 9.9%, 8.6%, 7.2%, and 4.7%, respectively. Conclusions: The results indicate that dual energy mammography can be used to accurately measure breast density. The variability in breast density estimation using dual energy mammography was lower than reader assessment rankings, standard histogram thresholding, and fuzzy C-mean algorithm. Improved quantification of breast density is expected to further enhance its utility as a risk factor for breast cancer.« less

Common Postmortem Computed Tomography Findings Following Atraumatic Death: Differentiation between Normal Postmortem Changes and Pathologic Lesions

PubMed Central

Gonoi, Wataru; Okuma, Hidemi; Shirota, Go; Shintani, Yukako; Abe, Hiroyuki; Takazawa, Yutaka; Fukayama, Masashi; Ohtomo, Kuni

2015-01-01

Computed tomography (CT) is widely used in postmortem investigations as an adjunct to the traditional autopsy in forensic medicine. To date, several studies have described postmortem CT findings as being caused by normal postmortem changes. However, on interpretation, postmortem CT findings that are seemingly due to normal postmortem changes initially, may not have been mere postmortem artifacts. In this pictorial essay, we describe the common postmortem CT findings in cases of atraumatic in-hospital death and describe the diagnostic pitfalls of normal postmortem changes that can mimic real pathologic lesions. PMID:26175579

Supraorbital Postmortem Brain Sampling for Definitive Quantitative Confirmation of Cerebral Sequestration of Plasmodium falciparum Parasites

PubMed Central

Milner, Danny A.; Valim, Clarissa; Luo, Robert; Playforth, Krupa B.; Kamiza, Steve; Molyneux, Malcolm E.; Seydel, Karl B.; Taylor, Terrie E.

2012-01-01

Background The conventional clinical case definition of cerebral malaria (CM) is imprecise but specificity is improved by a definitive clinical feature such as retinopathy or confirming sequestration of parasites in a post-mortem examination of the brain. A full autopsy is often not possible, since it is costly and may encounter resistance of the deceased's family. Methods We have assessed the use of a cytological smear of brain tissue, obtained post-mortem by supraorbital sampling, for the purpose of quantifying cerebral sequestration in children with fatal malaria in Blantyre, Malawi. We have compared this method to histological quantification of parasites at autopsy. Results The number of parasites present on cytological smears correlated with the proportion of vessels parasitized as assessed by histology of fixed and stained brain tissue. Use of cytological results in addition to the standard clinical case definition increases the specificity of the clinical case definition alone from 48.3% to 100% with a minimal change in sensitivity. Conclusions Post-mortem supraorbital sampling of brain tissue improves the specificity of the diagnosis of fatal cerebral malaria and provides accurate quantitative estimates of cerebral sequestration. This tool can be of great value in clinical, pathogenetic, and epidemiological research studies on cerebral malaria. PMID:22291197

[The foreign experience with the application of the modern radiodiagnostic methods for the estimation of prescription of death coming and time of infliction of injury].

PubMed

Fetisov, V A; Kuprina, T A; Sinitsyn, V E; Dubrova, S E; Filimonov, B A

2016-01-01

We undertook the analysis of the foreign publications concerning the application of the modern radiodiagnostic methods (including MSCT- and MRI-visualization) with reference to the solution of the traditional problems facing forensic medical expertise, such as the estimation of prescription of death coming and time of infliction of injury in the dead bodies. Both advantages and disadvantages of postmortem visualization of the corpses of adult subjects are discussed taking into consideration the period of time that elapsed between the death and the onset of the study as well as the character of the injuries. It was shown that the examination of the corpses using the up-to-date methods of radiodiagnostics prior to autopsy makes it possible for morphologists, jointly with radiologists, to identify, to see in the new light, and to evaluate the number of charges in the dead body, such as the alteration of the blood cell sedimentation rate, the formation of postmortem hypostases in the internal organs, the hardening of the walls of aorta and major blood vessels, right heart dilatation, gradual smoothing of the borderline between grey and white matter of the brain. Virtual autopsy can be useful , even for the study of such long-term processes in the corpses as putrefaction, saponification, mummification, and peat tanning. Moreover, this technique may be instrumental in the elucidation of the specific features of topographic-anatomical relationships between individual 'tissues and organs, detection of the concealed lesions, and a variety of pathological changes. Postmortem visualization allows for the quantitative evaluation of the severity of these transformations and the preliminary estimation of prescription of death coming. Also, radiodiagnostic methods can be employed to reliably visualize and measure various hemorrhagic events (from the density of such ones as liquid and clotted blood) in the tissues surrounding the fractures, in body cavities, and internal organs as well as to establish the facts of inter-vital aspiration of blood, alimentary masses, liquid and solid foreign bodies penetrating into the upper sections of the respiratory and gastrointestinal tracts as the consequence f an injury. It is concluded that the postmortem visualization techniques employed to estimate prescription of death coming and time of infliction of injury as well as other complicated problems facing forensic medical expertize need the further scientifically based development.

Differential methylation at the RELN gene promoter in temporal cortex from autistic and typically developing post-puberal subjects.

PubMed

Lintas, Carla; Sacco, Roberto; Persico, Antonio M

2016-01-01

Reelin plays a pivotal role in neurodevelopment and in post-natal synaptic plasticity and has been implicated in the pathogenesis of autism spectrum disorder (ASD). The reelin (RELN) gene expression is significantly decreased in ASD, both in the brain and peripherally. Methylation at the RELN gene promoter is largely triggered at puberty, and hypermethylation has been found in post-mortem brains of schizophrenic and bipolar patients. In this study, we assessed RELN gene methylation status in post-mortem temporocortical tissue samples (BA41/42 or 22) of six pairs of post-puberal individuals with ASD and typically developing subjects, matched for sex (male:female, M:F = 5:1), age, and post-mortem interval. ASD patients display a significantly higher number of methylated CpG islands and heavier methylation in the 5' region of the RELN gene promoter, spanning from -458 to -223 bp, whereas controls have more methylated CpG positions and greater extent of methylation at the 3' promoter region, spanning from -222 to +1 bp. The most upstream promoter region (-458 to -364 bp) is methylated only in ASD brains, while the most downstream region (-131 to +1 bp) is methylated exclusively in control brains. Within this general framework, three different methylation patterns are discernible, each correlated with different extents of reduction in reelin gene expression among ASD individuals compared to controls. The methylation pattern is different in ASD and control post-mortem brains. ASD-specific CpG positions, located in the most upstream gene promoter region, may exert a functional role potentially conferring ASD risk by blunting RELN gene expression.

The role of angiography in the congruence of cardiovascular measurements between autopsy and postmortem imaging.

PubMed

Troxler, Renaud; Minoiu, Costin; Vaucher, Paul; Michaud, Katarzyna; Doenz, Francesco; Ducrot, Kewin; Grabherr, Silke

2018-01-01

Postmortem CT angiography is the method of choice for the postmortem imaging investigations of the cardiovascular (CV) system. However, autopsy still remains the gold standard for CV measurement. Nevertheless, there are not any studies on CV measurements on the multi-phase postmortem angiography (MPMCTA) which includes comparisons with autopsy. Therefore, the aim of this study is to compare CV measurements between the native CT scan and the three phases of the MPMCTA to find out which of these modalities correlate the best with autopsy measurements. For this study, we selected retrospectively 50 postmortem cases that underwent both MPMCTA and autopsy. A comparison was carried out between the CV measurements obtained with imaging (aorta; heart cavities and cardiac wall thicknesses; maximum cardiac diameter and cardiothoracic ratio) and at the autopsy (aorta; cardiac valves, ventricular thicknesses, and weight). Our results show that the dynamic phase displays an advantage for the measurement of the aortas. However, the MPMCTA is not accurate to measure the cardiac wall thicknesses. The measurements of the heart cavities show no correlation with the heart valves. The cardiothoracic ratio measured by the MPMCTA shows no correlation with the heart weight. Nevertheless, the maximum cardiac diameter exhibits a correlation with the latter on the venous and dynamic phase. These results show that only few CV parameters measured with imaging correlate with measurement obtained at the autopsy. These results indicate that in order to better estimate values obtained at the autopsy, we need to define new reference values for the CV measurement on MPMCTA.

[Alcohol-related mortality in the assessments of hospital unit physicians and pathologists: analysis of accounting medical documents].

PubMed

Solov'ev, A G; Viaz'min, A M; Mordovskiĭ, É A; Krasil'nikov, S V

2014-01-01

To make a comparative analysis of the data available in the accounting medical documents drawn up at a multidisciplinary hospital on the level and structure of alcohol-related mortality (ARM) and to evaluate the efficiency of its accounting. Accounting medical documents, such as 453 inpatient cards (Form 003/y), 453 postmortem protocols (cards) (Form 013/H-80), and 453 death certificates (Form 106/y-08), were chosen as the basis for the study. The data of the final clinical and postmortem diagnoses in the patients who had died at hospital and their primary cause of death were comparatively analyzed. According to Form 003/y, ARM was 5.5%; the detection rate of alcohol-related disease (ARD) was 11% (95% confidence interval (CI), 8.3 to 14.3%); according to Form 013/H-80, ARM was 7.1% (95% CI, 4.9 to 9.8%) and the detection rate of ARD was 12.6% (95% CI, 9.7 to 16%). The consistency of the diagnoses of ARD as a main cause of death, made by hospital unit physicians and pathologists, is estimated as the mean--the Cohen's kappa coefficient (kappa) is 0.570) (p < 0.001). The results of the investigation suggest that there are 3 types of ARM, which differ in its level and structure: ARM in the assessments of hospital unit physicians; that in the assessments of pathologists, and that according to the death certificates drawn up. The consistency index for the diagnosis of ARD as a main cause of death indicates that the hospital unit physicians only determine the etiology of alcohol-related cause of death, without identifying it specifically.

Organic staining on bone from exposure to wood and other plant materials.

PubMed

Pollock, Corey R; Pokines, James T; Bethard, Jonathan D

2018-02-01

Determining the depositional environment and the postmortem alterations to a set of remains are necessary aspects of a forensic investigation to explain the circumstances surrounding the death of an individual. The present study examines organic staining as a method for reconstructing the depositional environment of skeletal remains and the taphonomic agents with which they came into contact. Organic staining results largely from tannins leaching from plant materials and therefore can be seen on bone deposited in wooden coffin environments or on terrestrial surfaces. The present study examines the hypothesis that the degree of staining observed on skeletal elements would increase as the length of exposure to the organic matter increased and that different plant materials and environments would leave different patterns or colorations of staining. The sample consisted of 165 pig (Sus scrofa) femora divided into four groups exposed to differing experimental conditions, including burial in direct contact with soil or burial in a simulated coffin environment, immersion in water with wood samples, and surface deposition with plant matter contact. The bones were removed once a month from their experimental environments and the level of staining was recorded qualitatively using the Munsell Soil Color Chart. In all of the experimental environments, staining was present after two months of exposure, and the color darkened across the bone surface with each episode of data collection. The results from the present study indicate that staining can manifest on bone within a relatively short time frame once skeletonization occurs and a variety of colorations or patterns of staining can manifest based on the plant material. The present research also demonstrates the potential of organic staining to aid in estimations of the postmortem interval as well as a depositional environmental reconstruction through plant species identification. Copyright © 2017 Elsevier B.V. All rights reserved.

Optimized lower leg injury probability curves from postmortem human subject tests under axial impacts.

PubMed

Yoganandan, Narayan; Arun, Mike W J; Pintar, Frank A; Szabo, Aniko

2014-01-01

Derive optimum injury probability curves to describe human tolerance of the lower leg using parametric survival analysis. The study reexamined lower leg postmortem human subjects (PMHS) data from a large group of specimens. Briefly, axial loading experiments were conducted by impacting the plantar surface of the foot. Both injury and noninjury tests were included in the testing process. They were identified by pre- and posttest radiographic images and detailed dissection following the impact test. Fractures included injuries to the calcaneus and distal tibia-fibula complex (including pylon), representing severities at the Abbreviated Injury Score (AIS) level 2+. For the statistical analysis, peak force was chosen as the main explanatory variable and the age was chosen as the covariable. Censoring statuses depended on experimental outcomes. Parameters from the parametric survival analysis were estimated using the maximum likelihood approach and the dfbetas statistic was used to identify overly influential samples. The best fit from the Weibull, log-normal, and log-logistic distributions was based on the Akaike information criterion. Plus and minus 95% confidence intervals were obtained for the optimum injury probability distribution. The relative sizes of the interval were determined at predetermined risk levels. Quality indices were described at each of the selected probability levels. The mean age, stature, and weight were 58.2±15.1 years, 1.74±0.08 m, and 74.9±13.8 kg, respectively. Excluding all overly influential tests resulted in the tightest confidence intervals. The Weibull distribution was the most optimum function compared to the other 2 distributions. A majority of quality indices were in the good category for this optimum distribution when results were extracted for 25-, 45- and 65-year-olds at 5, 25, and 50% risk levels age groups for lower leg fracture. For 25, 45, and 65 years, peak forces were 8.1, 6.5, and 5.1 kN at 5% risk; 9.6, 7.7, and 6.1 kN at 25% risk; and 10.4, 8.3, and 6.6 kN at 50% risk, respectively. This study derived axial loading-induced injury risk curves based on survival analysis using peak force and specimen age; adopting different censoring schemes; considering overly influential samples in the analysis; and assessing the quality of the distribution at discrete probability levels. Because procedures used in the present survival analysis are accepted by international automotive communities, current optimum human injury probability distributions can be used at all risk levels with more confidence in future crashworthiness applications for automotive and other disciplines.

Temperature-based death time estimation with only partially known environmental conditions.

PubMed

Mall, Gita; Eckl, Mona; Sinicina, Inga; Peschel, Oliver; Hubig, Michael

2005-07-01

The temperature-oriented death time determination is based on mathematical model curves of postmortem rectal cooling. All mathematical models require knowledge of the environmental conditions. In medico-legal practice homicide is sometimes not immediately suspected at the death scene but afterwards during external examination of the body. The environmental temperature at the death scene remains unknown or can only be roughly reconstructed. In such cases the question arises whether it is possible to estimate the time since death from rectal temperature data alone recorded over a longer time span. The present study theoretically deduces formulae which are independent of the initial and environmental temperatures and thus proves that the information needed for death time estimation is contained in the rectal temperature data. Since the environmental temperature at the death scene may differ from that during the temperature recording, an additional factor has to be used. This is that the body core is thermally well isolated from the environment and that the rectal temperature decrease after a sudden change of environmental temperature will continue for some time at a rate similar to that before the sudden change. The present study further provides a curve-fitting procedure for such scenarios. The procedure was tested in rectal cooling data of from 35 corpses using the most commonly applied model of Henssge. In all cases the time of death was exactly known. After admission to the medico-legal institute the bodies were kept at a constant environmental temperature for 12-36 h and the rectal temperatures were recorded continuously. The curve-fitting procedure led to valid estimates of the time since death in all experiments despite the unknown environmental conditions before admission to the institute. The estimation bias was investigated statistically. The 95% confidence intervals amounted to +/-4 h, which seems reasonable compared to the 95% confidence intervals of the Henssge model with known environmental temperature. The presented method may be of use for determining the time since death even in cases in which the environmental temperature and rectal temperature at the death scene have unintentionally not been recorded.

Publication Bias Currently Makes an Accurate Estimate of the Benefits of Enrichment Programs Difficult: A Postmortem of Two Meta-Analyses Using Statistical Power Analysis

ERIC Educational Resources Information Center

Warne, Russell T.

2016-01-01

Recently Kim (2016) published a meta-analysis on the effects of enrichment programs for gifted students. She found that these programs produced substantial effects for academic achievement (g = 0.96) and socioemotional outcomes (g = 0.55). However, given current theory and empirical research these estimates of the benefits of enrichment programs…

[Evaluation on stability of internal controls in human cardiac muscle by real-time RT-PCR during early postmortem interval].

PubMed

Zhang, Ping; Ma, Kai-Jun; Zhang, Heng; Wang, Hui-Jun; Shen, Yi-Wen; Chen, Long

2012-04-01

To explore the stability of internal controls in human cardiac muscle by real-time RT-PCR during early postmortem interval (PMI) in order to find the most stable marker. Ten individuals with similar environmental conditions (the average store temperature: 25 degrees C) and different PMI ranging from 4.3 to 22.3 h were selected. Total RNA was extracted from each sample and six commonly internal controls were used including beta-actin, GAPDH, B2M, U6, 18S rRNA and HSA-miR-1, and the expression was detected in cardiac muscle by real-time RT-PCR. The expression stability of internal controls was evaluated using genormPLUS software during early PMI. The internal control with the most stability was selected. The relationship between the most stable marker and its expression level affected by some other parameters such as age, gender and cause of death was also analyzed. The U6 showed the most stable expression during early PMI in cardiac muscle, and its expression level was not affected by those parameters including age, gender and cause of death (P > 0.05). U6 may be a valuable internal control for the study of relationship between PMI determination and degradation of nucleic acid in human cardiac muscle by real-time RT-PCR.

Determination of season at death using dental cementum increment analysis.

PubMed

Wedel, Vicki L

2007-11-01

Dental cementum anchors teeth into their sockets via the periodontal ligament. In mammals, dental cementum is laid down in alternating opaque and translucent bands representing winter (dormant) and summer (growth) seasons. Each pair of bands represents 1 year of life. Estimates of age at death based on counting pairs of bands are highly accurate. If the timing of the transition between winter and summer bands could be identified in humans, dental cementum increment analysis could be used to specify the season at death. This pilot project attempts to determine when these transitions occur and thus provide forensic anthropologists with a technique that would refine our estimates of postmortem interval. Extracted teeth were obtained from a local oral surgeon, embedded, sectioned, ground, polished, and examined under transmitted polarized light. The outermost increment was identified and measured along with other randomly chosen like bands. A transition from translucent to opaque bands was observed in teeth extracted in early October, while teeth extracted in early April exhibited nascent translucent bands. Further, significant correlations were observed between band thickness and number of days into either season, suggesting that band width increases as either season progresses. In this blind study, extracted teeth were effectively sorted into the spring/summer or fall/winter season 99% of the time.

The toxicological significance of post-mortem drug concentrations in bile.

PubMed

Ferner, Robin E; Aronson, Jeffrey K

2018-01-01

Some authors have proposed that post-mortem drug concentrations in bile are useful in estimating concentrations in blood. Both The International Association of Forensic Toxicologists (TIAFT) and the US Federal Aviation Administration recommend that samples of bile should be obtained in some circumstances. Furthermore, standard toxicological texts compare blood and bile concentrations, implying that concentrations in bile are of forensic value. To review the evidence on simultaneous measurements of blood and bile drug concentrations reported in the medical literature. We made a systematic search of EMBASE 1980-2016 using the search terms ("bile/" OR "exp drug bile level/concentration/") AND "drug blood level/concentration/", PubMed 1975-2017 for ("bile[tw]" OR "biliary[tw]") AND ("concentration[tw]" OR "concentrations[tw]" OR "level[tw]" OR "levels[tw]") AND "post-mortem[tw]" and also MEDLINE 1990-2016 for information on drugs whose biliary concentrations were mentioned in standard textbooks. The search was limited to human studies without language restrictions. We also examined recent reviews, indexes of relevant journals and citations in Web of Science and Google Scholar. We calculated the bile:blood concentration ratio. The searches together yielded 1031 titles with abstracts. We scanned titles and abstracts for relevance and retrieved 230, of which 161 were considered further. We excluded 49 papers because: the paper reported only one case (30 references); the data referred only to a metabolite (1); the work was published before 1980 (3); the information concerned only samples taken during life (10); or the paper referred to a toxin or unusual recreational drug (5). The remaining 112 papers provided data for analysis, with at least two observations for each of 58 drugs. Bile:blood concentration ratios: Median bile:blood concentration ratios varied from 0.18 (range 0.058-0.32) for dextromoramide to 520 (range 0.62-43,000) for buprenorphine. Median bile concentrations exceeded blood concentrations by one order of magnitude for several drugs, including dihydrocodeine, quetiapine and sildenafil; and by two orders of magnitude of for buprenorphine, colchicine and 3,4-methylenedioxy-methamphetamine (MDMA), among others. The minimum and maximum values for the ratio differed by a factor of three or more in three-quarters of the cases where data were available and by a factor of 10 or more for over half of the analytes. The data were difficult to find. Medline does not explicitly index the term "drug bile concentration". It may well be that other reports exist, although they would not alter our major conclusion. Many of the papers that contributed data failed to specify the source of the blood samples or the post-mortem interval, so that no judgment was possible regarding post-mortem redistribution in whole blood or bile. For most drugs, there are wide ranges of bile:blood concentration ratios, which means that bile and blood concentrations are generally poorly correlated. Bile concentration measurements cannot readily be used to establish post-mortem blood concentrations; nor can they be extrapolated to ante-mortem concentrations. However, because drug concentrations in bile often exceed those in blood, bile may allow qualitative identification of drugs present, even when the blood concentration is below the limit of detection.

Bilateral first rib anomalous articulations with pseudarthroses mimicking healing fractures in an infant with abusive head injury.

PubMed

Pasquale-Styles, Melissa A; Crowder, Christian M; Fridie, Jeannette; Milla, Sarah S

2014-11-01

Bilateral symmetric bone nodules were observed in the anterolateral first ribs of an infant with shaking injuries at autopsy. The location prompted diagnostic considerations of healing fractures versus anomalous articulations with pseudarthroses. The forensic pathologist worked with forensic anthropologists and pediatric radiologists to evaluate autopsy findings and compare premortem and postmortem X-rays. Gross examination of the bones by the pathologist and anthropologists confirmed bilateral, callus-like bone nodules in first-rib locations associated with pseudarthroses. Histologic examination of one of the bones further showed features most consistent with pseudarthrosis, not a healing fracture. Radiologists then compared multiple premortem and postmortem radiographs that showed no remodeling of the bone over a 2-week interval between the time of injury and death, which would be unexpected for a healing fracture in an infant. This multidisciplinary approach resulted in the appropriate diagnosis of pseudarthroses due to anomalous articulations, an uncommon finding in forensic pathology. © 2014 American Academy of Forensic Sciences.

Deaths Associated With Brotizolam Poisoning From a Single Drug Overdose: Four Reported Cases.

PubMed

Sakai, Kentaro; Saito, Kazuyuki; Takada, Aya; Hikiji, Wakako; Kikuchi, Yosuke; Fukunaga, Tatsushige

2018-03-01

Brotizolam is a short-acting hypnotic in the benzodiazepine family, and fatal poisonings by an overdose of brotizolam are rare. This report describes 4 cases of deaths associated with brotizolam poisoning from a single drug overdose. The ages ranged from 51 to 90 years, and the postmortem interval between death and tissue sampling was 1.5 to 2.5 days. These deaths were classified as 1 homicide and 3 suicides. The concentration of the brotizolam ranged from 0.05 to 0.21 mg/L in the blood samples. Ethanol, which could cause mild alcohol intoxication, was detected in the blood samples from 2 cases. Postmortem examinations did not find any significant pathologic conditions, except for a case of death by drowning in a bathtub due to brotizolam poisoning. These 4 cases suggest that a brotizolam overdose should not be underestimated in terms of its fatal effects, particularly when situations involve alcohol intoxication, injury subsequent to the poisoning, or underlying medical conditions including aging.

Cystic echinococcosis in marketed offal of sheep in Basrah, Iraq: Abattoir-based survey and a probabilistic model estimation of the direct economic losses due to hydatid cyst.

PubMed

Abdulhameed, Mohanad F; Habib, Ihab; Al-Azizz, Suzan A; Robertson, Ian

2018-02-01

Cystic echinococcosis (CE) is a highly endemic parasitic zoonosis in Iraq with substantial impacts on livestock productivity and human health. The objectives of this study were to study the abattoir-based occurrence of CE in marketed offal of sheep in Basrah province, Iraq, and to estimate, using a probabilistic modelling approach, the direct economic losses due to hydatid cysts. Based on detailed visual meat inspection, results from an active abattoir survey in this study revealed detection of hydatid cysts in 7.3% (95% CI: 5.4; 9.6) of 631 examined sheep carcasses. Post-mortem lesions of hydatid cyst were concurrently present in livers and lungs of more than half (54.3% (25/46)) of the positive sheep. Direct economic losses due to hydatid cysts in marketed offal were estimated using data from government reports, the one abattoir survey completed in this study, and expert opinions of local veterinarians and butchers. A Monte-Carlo simulation model was developed in a spreadsheet utilizing Latin Hypercube sampling to account for uncertainty in the input parameters. The model estimated that the average annual economic losses associated with hydatid cysts in the liver and lungs of sheep marketed for human consumption in Basrah to be US$72,470 (90% Confidence Interval (CI); ±11,302). The mean proportion of annual losses in meat products value (carcasses and offal) due to hydatid cysts in the liver and lungs of sheep marketed in Basrah province was estimated as 0.42% (90% CI; ±0.21). These estimates suggest that CE is responsible for considerable livestock-associated monetary losses in the south of Iraq. These findings can be used to inform different regional CE control program options in Iraq.

Repellent effect of some household products on fly attraction to cadavers.

PubMed

Charabidze, Damien; Bourel, Benoit; Hedouin, Valery; Gosset, Didier

2009-08-10

The most common task of a forensic entomologist is to determine an accurate minimum post-mortem interval (PMI) using necrophagous fly larvae found on carrion. More often, blowflies (Diptera: Calliphoridae) are the first insects to detect the cadaver and, if the circumstances are favourable, to leave eggs on the body. However, several studies reveal that products such as gas or paint found on the cadaver induce a delay in the colonisation of the body, leading to an under-estimate of the PMI. Six common household products (gas, mosquito citronella repellent, perfume, bleach, hydrochloric acid and soda) were added to dead rats (Rattus norvegicus) in a field (Lille Forensic Institute, France). The presence of necrophagous flies was checked at regular intervals during 1 month. This experiment was repeated at the same period for four consecutive years. Results clearly showed the repellent effect of three of the six tested substances: gas (petroleum spirit), perfume and mosquito citronella repellent, which resulted in a mean delay of several days in the appearance of the first Dipteran species. Experiments were then carried out in controlled conditions in order to confirm previous observations. An olfactometer was specially designed to observe the behaviour of female Calliphora vicina (Diptera: Calliphoridae) in response to mice (Mus musculus) cadaver odour stimuli combined with household products. Dead mouse odour was a strong attractive stimulus for most of the tested individuals. Furthermore, it was noticed that the presence of mosquito citronella repellent, perfume, hydrochloric acid and paradichlorobenzene produced a significant repellent effect on female flies. All these results together confirm the repellent effect of some household products on flies and the necessity for forensic entomologists to consider this hypothesis when estimating the PMI.

Postmortem time estimation using body temperature and a finite-element computer model.

PubMed

den Hartog, Emiel A; Lotens, Wouter A

2004-09-01

In the Netherlands most murder victims are found 2-24 h after the crime. During this period, body temperature decrease is the most reliable method to estimate the postmortem time (PMT). Recently, two murder cases were analysed in which currently available methods did not provide a sufficiently reliable estimate of the PMT. In both cases a study was performed to verify the statements of suspects. For this purpose a finite-element computer model was developed that simulates a human torso and its clothing. With this model, changes to the body and the environment can also be modelled; this was very relevant in one of the cases, as the body had been in the presence of a small fire. In both cases it was possible to falsify the statements of the suspects by improving the accuracy of the PMT estimate. The estimated PMT in both cases was within the range of Henssge's model. The standard deviation of the PMT estimate was 35 min in the first case and 45 min in the second case, compared to 168 min (2.8 h) in Henssge's model. In conclusion, the model as presented here can have additional value for improving the accuracy of the PMT estimate. In contrast to the simple model of Henssge, the current model allows for increased accuracy when more detailed information is available. Moreover, the sensitivity of the predicted PMT for uncertainty in the circumstances can be studied, which is crucial to the confidence of the judge in the results.

Postmortem aging and freezing and thawing storage enhance ability of early deboned chicken pectoralis major muscle to hold added salt water.

PubMed

Zhuang, H; Savage, E M

2012-05-01

The effects of postdeboning aging and frozen storage on water-holding capacity (WHC) of chicken breast pectoralis major muscle were investigated. Broiler breast muscle was removed from carcasses either early postmortem (2 h) or later postmortem (24 h). Treatments included: no postdeboning aging; 1-d postdeboning aging at 2°C, 7-d postdeboning aging (2-h deboned meat only), and 6-d storage at -20°C plus 1-d thawing at 2°C (freezing and thawing treatment, 2-h deboned meat only). The WHC was determined by cooking loss, drip loss, a filter paper press method (results were presented as expressible fluid), and a salt-induced swelling and centrifugation method (results were presented as percentage of salt-induced water gain). There were no differences for WHC estimated by cooking loss and expressible fluid between the treatments. Only the freezing and thawing treatment resulted in a significant increase in drip loss. The average percentage of salt-induced water gains by the 24-h deboned samples, postdeboning aged 2 h samples, and frozen 2 h sample, which did not differ from each other, were significantly higher than that by the 2-h deboned sample. These results indicate that regardless of method (carcass aging vs. postdeboning aging) and time (aging for 1 d vs. for 7 d), postmortem aging more than 1 d does not affect WHC of the early deboned samples measured by dripping, cooking, and pressing. However, postmortem carcass aging, postdeboning aging, and freezing and thawing storage can significantly enhance the ability of chicken breast meat to hold added salt water or WHC measured by the salt-induced swelling and centrifuge method.

Is the formula of Traub still up to date in antemortem blood glucose level estimation?

PubMed

Palmiere, Cristian; Sporkert, Frank; Vaucher, Paul; Werner, Dominique; Bardy, Daniel; Rey, François; Lardi, Christelle; Brunel, Christophe; Augsburger, Marc; Mangin, Patrice

2012-05-01

According to the hypothesis of Traub, also known as the 'formula of Traub', postmortem values of glucose and lactate found in the cerebrospinal fluid or vitreous humor are considered indicators of antemortem blood glucose levels. However, because the lactate concentration increases in the vitreous and cerebrospinal fluid after death, some authors postulated that using the sum value to estimate antemortem blood glucose levels could lead to an overestimation of the cases of glucose metabolic disorders with fatal outcomes, such as diabetic ketoacidosis. The aim of our study, performed on 470 consecutive forensic cases, was to ascertain the advantages of the sum value to estimate antemortem blood glucose concentrations and, consequently, to rule out fatal diabetic ketoacidosis as the cause of death. Other biochemical parameters, such as blood 3-beta-hydroxybutyrate, acetoacetate, acetone, glycated haemoglobin and urine glucose levels, were also determined. In addition, postmortem native CT scan, autopsy, histology, neuropathology and toxicology were performed to confirm diabetic ketoacidosis as the cause of death. According to our results, the sum value does not add any further information for the estimation of antemortem blood glucose concentration. The vitreous glucose concentration appears to be the most reliable marker to estimate antemortem hyperglycaemia and, along with the determination of other biochemical markers (such as blood acetone and 3-beta-hydroxybutyrate, urine glucose and glycated haemoglobin), to confirm diabetic ketoacidosis as the cause of death.

Breast density quantification with cone-beam CT: A post-mortem study

PubMed Central

Johnson, Travis; Ding, Huanjun; Le, Huy Q.; Ducote, Justin L.; Molloi, Sabee

2014-01-01

Forty post-mortem breasts were imaged with a flat-panel based cone-beam x-ray CT system at 50 kVp. The feasibility of breast density quantification has been investigated using standard histogram thresholding and an automatic segmentation method based on the fuzzy c-means algorithm (FCM). The breasts were chemically decomposed into water, lipid, and protein immediately after image acquisition was completed. The percent fibroglandular volume (%FGV) from chemical analysis was used as the gold standard for breast density comparison. Both image-based segmentation techniques showed good precision in breast density quantification with high linear coefficients between the right and left breast of each pair. When comparing with the gold standard using %FGV from chemical analysis, Pearson’s r-values were estimated to be 0.983 and 0.968 for the FCM clustering and the histogram thresholding techniques, respectively. The standard error of the estimate (SEE) was also reduced from 3.92% to 2.45% by applying the automatic clustering technique. The results of the postmortem study suggested that breast tissue can be characterized in terms of water, lipid and protein contents with high accuracy by using chemical analysis, which offers a gold standard for breast density studies comparing different techniques. In the investigated image segmentation techniques, the FCM algorithm had high precision and accuracy in breast density quantification. In comparison to conventional histogram thresholding, it was more efficient and reduced inter-observer variation. PMID:24254317

Development of the Oriental Latrine Fly, Chrysomya megacephala (Diptera: Calliphoridae), at Five Constant Temperatures.

PubMed

Gruner, S V; Slone, D H; Capinera, J L; Turco, M P

2017-03-01

Chrysomya megacephala (Fabricius) is a forensically important fly that is found throughout the tropics and subtropics. We calculated the accumulated development time and transition points for each life stage from eclosion to adult emergence at five constant temperatures: 15, 20, 25, 30, and 35 °C. For each transition, the 10th, 50th, and 90th percentiles were calculated with a logistic linear model. The mean transition times and % survivorship were determined directly from the raw laboratory data. Development times of C. megacephala were compared with that of two other closely related species, Chrysomya rufifacies (Macquart) and Phormia regina (Meigen). Ambient and larval mass temperatures were collected from field studies conducted from 2001-2004. Field study data indicated that adult fly activity was reduced at lower ambient temperatures, but once a larval mass was established, heat generation occurred. These development times and durations can be used for estimation of a postmortem interval (PMI). © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Technical note: unsafe rectal temperature measurements due to delayed warming of the thermocouple by using a condom. An issue concerning the estimation of the postmortem interval by using Henßge's nomogram.

PubMed

Krap, Tristan; Meurs, Joris; Boertjes, Janine; Duijst, Wilma

2016-03-01

In some cases, in the Netherlands, an additional layer is being added to the thermocouple, used to measure the rectal temperature in medicolegal death investigations. Because of this deviation from the standard method, questions arose regarding the accuracy and precision of the measured temperature. Therefore, a cooling experiment was carried out on a round body made of agar with an average thermal conductivity of 0.454 W/(m °C) while measuring the temperature with and without an additional layer around the thermocouple for three different starting temperatures: 36, 30, and 27 °C. The results show a significant difference between the measured values for the first 5 min when comparing with and without the additional layer. Further, a decrease in precision is present within the first minutes when using an additional layer. Therefore, it is concluded that it is best to measure the rectal temperature without an additional layer around the thermocouple and caution should be taken when measuring with an additional layer.

A checklist of beetles (Insecta, Coleoptera) on pig carcasses in the suburban area of southwestern China: A preliminary study and its forensic relevance.

PubMed

Lyu, Zhou; Wan, Li-Hua; Yang, Yong-Qiang; Tang, Rui; Xu, Lyu-Zi

2016-07-01

Examining the succession pattern of carrion insects on vertebrate carcasses is widely accepted as an effective method to estimate the postmortem interval (PMI) of decayed bodies. Investigation of the community of sarcosaprophagous insects, especially flies and beetles, is the foundation of the succession pattern study. This study aimed to investigate the sarcosaprophagous beetles succession on animal carcasses in the suburban area of southwestern China and to establish a basic catalog for forensic application. The present study was conducted in 2013 in a mountain in Chongqing municipality with modified Schoenly traps. Carcasses of miniature pig were used to simulate human bodies. For most carcasses, five decomposition stages were observed. A total of 2108 adult coleopterans belonging to at least 61 species and 18 families were collected in the study, and most of the specimens occurred at the advanced decay stage. Omosita colon (Linnaeus, 1758), Necrodes nigricornis (Harold, 1875), Necrobia ruficollis (Fabricius, 1775) and Neosilusa ceylonica (Kraatz, 1857) were the dominant species. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Utility of GenBank and the Barcode of Life Data Systems (BOLD) for the identification of forensically important Diptera from Belgium and France

PubMed Central

Sonet, Gontran; Jordaens, Kurt; Braet, Yves; Bourguignon, Luc; Dupont, Eréna; Backeljau, Thierry; De Meyer, Marc; Desmyter, Stijn

2013-01-01

Abstract Fly larvae living on dead corpses can be used to estimate post-mortem intervals. The identification of these flies is decisive in forensic casework and can be facilitated by using DNA barcodes provided that a representative and comprehensive reference library of DNA barcodes is available. We constructed a local (Belgium and France) reference library of 85 sequences of the COI DNA barcode fragment (mitochondrial cytochrome c oxidase subunit I gene), from 16 fly species of forensic interest (Calliphoridae, Muscidae, Fanniidae). This library was then used to evaluate the ability of two public libraries (GenBank and the Barcode of Life Data Systems – BOLD) to identify specimens from Belgian and French forensic cases. The public libraries indeed allow a correct identification of most specimens. Yet, some of the identifications remain ambiguous and some forensically important fly species are not, or insufficiently, represented in the reference libraries. Several search options offered by GenBank and BOLD can be used to further improve the identifications obtained from both libraries using DNA barcodes. PMID:24453564

Diagnostic performance characteristics of a rapid field test for anthrax in cattle.

PubMed

Muller, Janine; Gwozdz, Jacek; Hodgeman, Rachel; Ainsworth, Catherine; Kluver, Patrick; Czarnecki, Jill; Warner, Simone; Fegan, Mark

2015-07-01

Although diagnosis of anthrax can be made in the field with a peripheral blood smear, and in the laboratory with bacterial culture or molecular based tests, these tests require either considerable experience or specialised equipment. Here we report on the evaluation of the diagnostic sensitivity and specificity of a simple and rapid in-field diagnostic test for anthrax, the anthrax immunochromatographic test (AICT). The AICT detects the protective antigen (PA) component of the anthrax toxin present within the blood of an animal that has died from anthrax. The test provides a result in 15min and offers the advantage of avoiding the necessity for on-site necropsy and subsequent occupational risks and environmental contamination. The specificity of the test was determined by testing samples taken from 622 animals, not infected with Bacillus anthracis. Diagnostic sensitivity was estimated on samples taken from 58 animals, naturally infected with B. anthracis collected over a 10-year period. All samples used to estimate the diagnostic sensitivity and specificity of the AICT were also tested using the gold standard of bacterial culture. The diagnostic specificity of the test was estimated to be 100% (99.4-100%; 95% CI) and the diagnostic sensitivity was estimated to be 93.1% (83.3-98.1%; 95% CI) (Clopper-Pearson method). Four samples produced false negative AICT results. These were among 9 samples, all of which tested positive for B. anthracis by culture, where there was a time delay between collection and testing of >48h and/or the samples were collected from animals that were >48h post-mortem. A statistically significant difference (P<0.001; Fishers exact test) was found between the ability of the AICT to detect PA in samples from culture positive animals <48h post-mortem, 49 of 49, Se=100% (92.8-100%; 95% CI) compared with samples tested >48h post-mortem 5 of 9 Se=56% (21-86.3%; 95% CI) (Clopper-Pearson method). Based upon these results a post hoc cut-off for use of the AICT of 48h post-mortem was applied, Se=100% (92.8-100%; 95% CI) and Sp=100% (99.4-100%; 95% CI). The high diagnostic sensitivity and specificity and the simplicity of the AICT enables it to be used for active surveillance in areas with a history of anthrax, or used as a preliminary tool in investigating sudden, unexplained death in cattle. Copyright © 2015 Elsevier B.V. All rights reserved.

Estimating the age of Lucilia illustris during the intrapuparial period using two approaches: Morphological changes and differential gene expression.

PubMed

Wang, Yu; Gu, Zhi-Ya; Xia, Shui-Xiu; Wang, Jiang-Feng; Zhang, Ying-Na; Tao, Lu-Yang

2018-06-01

Lucilia illustris (Meigen, 1826) (Diptera: Calliphoridae) is a cosmopolitan species of fly that has forensic and medical significance. However, there is no relevant study regarding the determination of the age of this species during the intrapuparial period. In this study, we investigated the changes in both morphology and differential gene expression during intrapuparial development, with an aim to estimate the age of L. illustris during the intrapuparial stage. The overall intrapuparial morphological changes of L. illustris were divided into 12 substages. Structures such as the compound eyes, mouthparts, antennae, thorax, legs, wings, and abdomen, each capable of indicating age during the intrapuparial stage, were observed in detail, and the developmental progression of each of these structures was divided into six to eight stages. We recorded the time range over which each substage or structure appeared. The differential expression of the three genes 15_2, actin, and tbp previously identified for predicting the timing of intrapuparial development was measured during L. illustris metamorphosis. The expression of these genes was quantified by real-time PCR, and the results revealed that these genes can be used to estimate the age of L. illustris during the intrapuparial period, as they exhibit regular changes and temperature dependence. This study provides an important basis for estimating the minimum postmortem interval (PMI min ) in forensic entomology according to changes in intrapuparial development and differential gene expression. Furthermore, combination of the two approaches can generate a more precise PMI min than either approach alone. Copyright © 2018 Elsevier B.V. All rights reserved.

Development of the Forensically Important Beetle Creophilus maxillosus (Coleoptera: Staphylinidae) at Constant Temperatures.

PubMed

Wang, Y; Yang, J B; Wang, J F; Li, L L; Wang, M; Yang, L J; Tao, L Y; Chu, J; Hou, Y D

2017-03-01

Creophilus maxillosus (L., 1758) is a common and widely distributed beetle species found on corpses, and its development duration is far longer than species belonging to the genus Calliphoridae and Sarcophagidae. Therefore, C. maxillosus can be used as a supplementary indicator to estimate minimum postmortem interval (PMImin), and could greatly extend the range of PMImin when the primary colonizers are no longer associated with the corpse or have emerged from pupae. Better descriptions of C. maxillosus development are needed to apply this species for forensic investigations. In this study, the development of C. maxillosus at seven constant temperatures ranging from 17.5-32.5 °C was studied. Through regression analyses, the simulation equations of larval body length variation with time after hatching were obtained. Isomegalen diagrams of the changes of larval body length over time at specific temperatures, and the isomorphen diagrams on the duration of different developmental milestones at specific temperatures were generated. In addition, thermal summation models of different developmental stages and the overall development process of C. maxillosus were generated through regression analysis, by estimating the development threshold temperatures (D0) and the thermal summation constants (K). These results provide important tools for forensic investigations to generate a long-range of PMImin estimation based on the development of C. maxillosus. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Optimising crime scene temperature collection for forensic entomology casework.

PubMed

Hofer, Ines M J; Hart, Andrew J; Martín-Vega, Daniel; Hall, Martin J R

2017-01-01

The value of minimum post-mortem interval (minPMI) estimations in suspicious death investigations from insect evidence using temperature modelling is indisputable. In order to investigate the reliability of the collected temperature data used for modelling minPMI, it is necessary to study the effects of data logger location on the accuracy and precision of measurements. Digital data logging devices are the most commonly used temperature measuring devices in forensic entomology, however, the relationship between ambient temperatures (measured by loggers) and body temperatures has been little studied. The placement of loggers in this study in three locations (two outdoors, one indoors) had measurable effects when compared with actual body temperature measurements (simulated with pig heads), some more significant than others depending on season, exposure to the environment and logger location. Overall, the study demonstrated the complexity of the question of optimal logger placement at a crime scene and the potential impact of inaccurate temperature data on minPMI estimations, showing the importance of further research in this area and development of a standard protocol. Initial recommendations are provided for data logger placement (within a Stevenson Screen where practical), situations to avoid (e.g. placement of logger in front of windows when measuring indoor temperatures), and a baseline for further research into producing standard guidelines for logger placement, to increase the accuracy of minPMI estimations and, thereby, the reliability of forensic entomology evidence in court. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The role of spatial aggregation in forensic entomology.

PubMed

Fiene, Justin G; Sword, Gregory A; Van Laerhoven, Sherah L; Tarone, Aaron M

2014-01-01

A central concept in forensic entomology is that arthropod succession on carrion is predictable and can be used to estimate the postmortem interval (PMI) of human remains. However, most studies have reported significant variation in successional patterns, particularly among replicate carcasses, which has complicated estimates of PMIs. Several forensic entomology researchers have proposed that further integration of ecological and evolutionary theory in forensic entomology could help advance the application of succession data for producing PMI estimates. The purpose of this essay is to draw attention to the role of spatial aggregation of arthropods among carrion resources as a potentially important aspect to consider for understanding and predicting the assembly of arthropods on carrion over time. We review ecological literature related to spatial aggregation of arthropods among patchy and ephemeral resources, such as carrion, and when possible integrate these results with published forensic literature. We show that spatial aggregation of arthropods across resources is commonly reported and has been used to provide fundamental insight for understanding regional and local patterns of arthropod diversity and coexistence. Moreover, two suggestions are made for conducting future research. First, because intraspecific aggregation affects species frequency distributions across carcasses, data from replicate carcasses should not be combined, but rather statistically quantified to generate occurrence probabilities. Second, we identify a need for studies that tease apart the degree to which community assembly on carrion is spatially versus temporally structured, which will aid in developing mechanistic hypotheses on the ecological factors shaping community assembly on carcasses.

Postmortem CT Angiography Compared with Autopsy: A Forensic Multicenter Study.

PubMed

Grabherr, Silke; Heinemann, Axel; Vogel, Hermann; Rutty, Guy; Morgan, Bruno; Woźniak, Krzysztof; Dedouit, Fabrice; Fischer, Florian; Lochner, Stefanie; Wittig, Holger; Guglielmi, Giuseppe; Eplinius, Franziska; Michaud, Katarzyna; Palmiere, Cristian; Chevallier, Christine; Mangin, Patrice; Grimm, Jochen M

2018-05-01

Purpose To determine if postmortem computed tomography (CT) and postmortem CT angiography help to detect more lesions than autopsy in postmortem examinations, to evaluate the strengths and weaknesses of each method, and to define their indications. Materials and Methods Postmortem CT angiography was performed on 500 human corpses and followed by conventional autopsy. Nine centers were involved. All CT images were read by an experienced team including one forensic pathologist and one radiologist, blinded to the autopsy results. All findings were recorded for each method and categorized by anatomic structure (bone, organ parenchyma, soft tissue, and vascular) and relative importance in the forensic case (essential, useful, and unimportant). Results Among 18 654 findings, autopsies helped to identify 61.3% (11 433 of 18 654), postmortem CT helped to identify 76.0% (14 179 of 18 654), and postmortem CT angiography helped to identify 89.9% (16 780 of 18 654; P < .001). Postmortem CT angiography was superior to autopsy, especially at helping to identify essential skeletal lesions (96.1% [625 of 650] vs 65.4% [425 of 650], respectively; P < .001) and vascular lesions (93.5% [938 of 1003] vs 65.3% [655 of 1003], respectively; P < .001). Among the forensically essential findings, 23.4% (1029 of 4393) were not detected at autopsy, while only 9.7% (428 of 4393) were missed at postmortem CT angiography (P < .001). The best results were obtained when postmortem CT angiography was combined with autopsy. Conclusion Postmortem CT and postmortem CT angiography and autopsy each detect important lesions not detected by the other method. More lesions were identified by combining postmortem CT angiography and autopsy, which may increase the quality of postmortem diagnosis. Online supplemental material is available for this article.

Diagnosis of myocardial ischemia combining multiphase postmortem CT-angiography, histology, and postmortem biochemistry.

PubMed

Vanhaebost, Jessica; Ducrot, Kewin; de Froidmont, Sébastien; Scarpelli, Maria Pia; Egger, Coraline; Baumann, Pia; Schmit, Gregory; Grabherr, Silke; Palmiere, Cristian

2017-02-01

The aim of this study was to assess whether the identification of pathological myocardial enhancement at multiphase postmortem computed tomography angiography was correlated with increased levels of troponin T and I in postmortem serum from femoral blood as well as morphological findings of myocardial ischemia. We further aimed to investigate whether autopsy cases characterized by increased troponin T and I concentrations as well as morphological findings of myocardial ischemia were also characterized by pathological myocardial enhancement at multiphase postmortem computed tomography angiography. Two different approaches were used. In one, 40 forensic autopsy cases that had pathological enhancement of the myocardium (mean Hounsfield units ≥95) observed at postmortem angiography were retrospectively selected. In the second approach, 40 forensic autopsy cases that had a cause of death attributed to acute myocardial ischemia were retrospectively selected. The preliminary results seem to indicate that the identification of a pathological enhancement of the myocardium at postmortem angiography is associated with the presence of increased levels of cardiac troponins in postmortem serum and morphological findings of ischemia. Analogously, a pathological enhancement of the myocardium at postmortem angiography can be retrospectively found in the great majority of autopsy cases characterized by increased cardiac troponin levels in postmortem serum and morphological findings of myocardial ischemia. Multiphase postmortem computed tomography angiography is a useful tool in the postmortem setting for investigating ischemically damaged myocardium.

"Blind spots" in forensic autopsy: improved detection of retrobulbar hemorrhage and orbital lesions by postmortem computed tomography (PMCT).

PubMed

Flach, P M; Egli, T C; Bolliger, S A; Berger, N; Ampanozi, G; Thali, M J; Schweitzer, W

2014-09-01

The purpose of this study was to correlate the occurrence of retrobulbar hemorrhage (RBH) with mechanism of injury, external signs and autopsy findings to postmortem computed tomography (PMCT). Six-teen subjects presented with RBH and underwent PMCT, external inspection and conventional autopsy. External inspection was evaluated for findings of the bulbs, black eye, raccoon eyes and Battle's sign. Fractures of the viscerocranium, orbital lesions and RBH were evaluated by PMCT. Autopsy and PMCT was evaluated for orbital roof and basilar skull fracture. The leading manner of death was accident with central regulatory failure in cases of RBH (31.25%). Imaging showed a high sensitivity in detection of orbital roof and basilar skull fractures (100%), but was less specific compared to autopsy. Volume of RBH (0.1-2.4ml) correlated positively to the presence of Battle's sign (p<0.06) and the postmortem interval. Ecchymosis on external inspection correlated with RBH. There was a statistical significant correlation between bulbar lesion and RBH. Orbital roof fracture count weakly correlated with the total PMCT derived RBH volume. Maxillary hemosinus correlated to maxillary fractures, but not to RBH. RBH are a specific finding in forensically relevant head trauma. PMCT is an excellent tool in detecting and quantifying morphological trauma findings particularly in the viscerocranium, one of the most relevant "blind spots" of classic autopsy. PMCT was superior in detecting osseous lesions, scrutinizing autopsy as the gold standard. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

An overview of gamma-hydroxybutyric acid: pharmacodynamics, pharmacokinetics, toxic effects, addiction, analytical methods, and interpretation of results.

PubMed

Andresen, H; Aydin, B E; Mueller, A; Iwersen-Bergmann, S

2011-09-01

Abuse of gamma-hydroxybutyric acid (GHB) has been known since the early 1990's, but is not as widespread as the consumption of other illegal drugs. However, the number of severe intoxications with fatal outcomes is comparatively high; not the least of which is brought about by the consumption of the currently legal precursor substances gamma-butyrolactone (GBL) and 1,4-butanediol (1,4-BD). In regards to previous assumptions, addiction to GHB or its analogues can occur with severe symptoms of withdrawal. Moreover, GHB can be used for drug-facilitated sexual assaults. Its pharmacological effects are generated mainly by interaction with both GABA(B) and GHB receptors, as well as its influence on other transmitter systems in the human brain. Numerous analytical methods for determining GHB using chromatographic techniques were published in recent years, and an enzymatic screening method was established. However, the short window of GHB detection in blood or urine due to its rapid metabolism is a challenge. Furthermore, despite several studies addressing this problem, evaluation of analytical results can be difficult: GHB is a metabolite of GABA (gamma-aminobutyric acid); a differentiation between endogenous and exogenous concentrations has to be made. Apart from this, in samples with a longer storage interval and especially in postmortem specimens, higher levels can be measured due to GHB generation during this postmortem interval or storage time. Copyright © 2011 John Wiley & Sons, Ltd.

Skin analysis following dermal exposure to kerosene in rats: the effects of postmortem exposure and fire.

PubMed

Hieda, Yoko; Tsujino, Yoshio; Xue, Yuying; Takayama, Koji; Fujihara, Junko; Kimura, Kojiro; Dekio, Satoshi

2004-02-01

To evaluate the usefulness of skin analysis for the forensic examination of cases involving postmortem dermal exposure to kerosene and/or fire, an experimental study using rats was performed. Rats received dermal exposure to kerosene before or after death, and the effect of fire was determined by burning an area of exposed skin after death. Kerosene concentrations in skin and blood were determined by gas chromatography-mass spectrometry and microscopic observation was performed for skin samples. No differences were observed in skin kerosene levels between antemortem and postmortem exposure. Kerosene concentrations in mildly burned skin where the stratum corneum (SC) was retained were approximately 84% compared to those in non-burned exposed skin, whereas concentrations in severely burned skin where the SC was almost completely burned off were 28% of non-burned skin. Even in non-exposed control skin 14% of the original kerosene concentrations could be detected, which was considered to be caused by contamination during the experimental protocol combined with kerosene's property of a high affinity for the SC. These results suggest that (1) skin analysis is useful in estimating the type of petroleum product involved in crimes or accidents even for postmortem exposure, (2) whether the SC is retained or not primarily determined the kerosene levels in burned skin, and (3) attention must be paid to evaluate the results obtained from skin samples in the light of the circumstances surrounding the case.

Effect of body mass and clothing on decomposition of pig carcasses.

PubMed

Matuszewski, Szymon; Konwerski, Szymon; Frątczak, Katarzyna; Szafałowicz, Michał

2014-11-01

Carcass mass and carcass clothing are factors of potential high forensic importance. In casework, corpses differ in mass and kind or extent of clothing; hence, a question arises whether methods for post-mortem interval estimation should take these differences into account. Unfortunately, effects of carcass mass and clothing on specific processes in decomposition and related entomological phenomena are unclear. In this article, simultaneous effects of these factors are analysed. The experiment followed a complete factorial block design with four levels of carcass mass (small carcasses 5-15 kg, medium carcasses 15.1-30 kg, medium/large carcasses 35-50 kg, large carcasses 55-70 kg) and two levels of carcass clothing (clothed and unclothed). Pig carcasses (N = 24) were grouped into three blocks, which were separated in time. Generally, carcass mass revealed significant and frequently large effects in almost all analyses, whereas carcass clothing had only minor influence on some phenomena related to the advanced decay. Carcass mass differently affected particular gross processes in decomposition. Putrefaction was more efficient in larger carcasses, which manifested itself through earlier onset and longer duration of bloating. On the other hand, active decay was less efficient in these carcasses, with relatively low average rate, resulting in slower mass loss and later onset of advanced decay. The average rate of active decay showed a significant, logarithmic increase with an increase in carcass mass, but only in these carcasses on which active decay was driven solely by larval blowflies. If a blowfly-driven active decay was followed by active decay driven by larval Necrodes littoralis (Coleoptera: Silphidae), which was regularly found in medium/large and large carcasses, the average rate showed only a slight and insignificant increase with an increase in carcass mass. These results indicate that lower efficiency of active decay in larger carcasses is a consequence of a multi-guild and competition-related pattern of this process. Pattern of mass loss in large and medium/large carcasses was not sigmoidal, but rather exponential. The overall rate of decomposition was strongly, but not linearly, related to carcass mass. In a range of low mass decomposition rate increased with an increase in mass, then at about 30 kg, there was a distinct decrease in rate, and again at about 50 kg, the rate slightly increased. Until about 100 accumulated degree-days larger carcasses gained higher total body scores than smaller carcasses. Afterwards, the pattern was reversed; moreover, differences between classes of carcasses enlarged with the progress of decomposition. In conclusion, current results demonstrate that cadaver mass is a factor of key importance for decomposition, and as such, it should be taken into account by decomposition-related methods for post-mortem interval estimation.

Dutch guideline for clinical foetal-neonatal and paediatric post-mortem radiology, including a review of literature.

PubMed

Sonnemans, L J P; Vester, M E M; Kolsteren, E E M; Erwich, J J H M; Nikkels, P G J; Kint, P A M; van Rijn, R R; Klein, W M

2018-06-01

Clinical post-mortem radiology is a relatively new field of expertise and not common practice in most hospitals yet. With the declining numbers of autopsies and increasing demand for quality control of clinical care, post-mortem radiology can offer a solution, or at least be complementary. A working group consisting of radiologists, pathologists and other clinical medical specialists reviewed and evaluated the literature on the diagnostic value of post-mortem conventional radiography (CR), ultrasonography, computed tomography (PMCT), magnetic resonance imaging (PMMRI), and minimally invasive autopsy (MIA). Evidence tables were built and subsequently a Dutch national evidence-based guideline for post-mortem radiology was developed. We present this evaluation of the radiological modalities in a clinical post-mortem setting, including MIA, as well as the recently published Dutch guidelines for post-mortem radiology in foetuses, neonates, and children. In general, for post-mortem radiology modalities, PMMRI is the modality of choice in foetuses, neonates, and infants, whereas PMCT is advised in older children. There is a limited role for post-mortem CR and ultrasonography. In most cases, conventional autopsy will remain the diagnostic method of choice. Based on a literature review and clinical expertise, an evidence-based guideline was developed for post-mortem radiology of foetal, neonatal, and paediatric patients. What is Known: • Post-mortem investigations serve as a quality check for the provided health care and are important for reliable epidemiological registration. • Post-mortem radiology, sometimes combined with minimally invasive techniques, is considered as an adjunct or alternative to autopsy. What is New: • We present the Dutch guidelines for post-mortem radiology in foetuses, neonates and children. • Autopsy remains the reference standard, however minimal invasive autopsy with a skeletal survey, post-mortem computed tomography, or post-mortem magnetic resonance imaging can be complementary thereof.

Plasma soluble CD163 is associated with postmortem brain pathology in human immunodeficiency virus infection.

PubMed

Bryant, Alex K; Moore, David J; Burdo, Tricia H; Lakritz, Jessica R; Gouaux, Ben; Soontornniyomkij, Virawudh; Achim, Cristian L; Masliah, Eliezer; Grant, Igor; Levine, Andrew J; Ellis, Ronald J

2017-04-24

Higher plasma soluble cluster of differentiation (CD)163 (sCD163), shed by monocytes and macrophages, correlates with neurocognitive impairment in HIV infection. We hypothesized that higher antemortem plasma or cerebrospinal fluid (CSF) sCD163 would be associated with greater postmortem neurodegeneration and/or microgliosis. Retrospective, postmortem observational study. We measured sCD163 levels in antemortem plasma (n = 54) and CSF (n = 32) samples from 74 HIV-seropositive participants (median 5 months before death) who donated their brains to research at autopsy. Postmortem, we quantified markers of synaptodendritic damage (microtubule-associated protein 2, synaptophysin), microgliosis [human leukocyte antigen DR (HLA-DR), ionized calcium-binding adaptor molecule 1], astrocytosis (glial fibrillary acidic protein), and impaired protein clearance (β-amyloid) in frontal cortex, hippocampus, putamen, and internal capsule. Multivariable least-squares regression was used to evaluate the association between plasma or CSF sCD163 and histological measures, correcting for multiple comparisons. Higher plasma sCD163 was associated with lower microtubule-associated protein 2 in frontal cortex [B = -0.23, 95% confidence interval (CI) -0.41 to -0.06, P = 0.04], putamen (B = 0.32, 95% CI -0.52 to -0.12, P = 0.02), and hippocampus (B = -0.23, 95% CI -0.35 to -0.10, P = 0.01), and with lower synaptophysin in hippocampus (B = -0.25, 95% CI -0.42 to -0.03, P = 0.02) but not putamen or frontal cortex (P > 0.05). Higher plasma sCD163 was associated with higher HLA-DR in putamen (B = 0.17, 95% CI 0.08 to 0.26, P = 0.008). CSF sCD163 was not associated with any histological measure (P > 0.05). Higher plasma sCD163 in life is associated with greater synaptodendritic damage and microglial activation in cortical and subcortical brain regions.

Bleedout efficiency, carcass damage, and rigor mortis development following electrical stunning or carbon dioxide stunning on a shackle line.

PubMed

Kang, I S; Sams, A R

1999-01-01

In Experiment 1, 400 male broilers were stunned using a gradient of 40 to 60% CO2 over a period of 25 s or a 1% brine solution that was electrically charged (35 mA) for 7 s. Blood loss during bleeding was measured in 30-s intervals for a total of 120 s. After conventional processing and chilling, carcass damage was subjectively evaluated. Results indicated that the birds stunned with electricity bled faster than the CO2-stunned birds until 60 s. However, the cumulative blood loss was not different after 90 s. Carcass damage evaluation indicated that birds stunned with CO2 had a significantly lower percentage of broken clavicles, and had fewer hemorrhages on the surface of the Pectoralis. However, there was no difference between the two stunning methods in the frequency of damage at the shoulder. In Experiment 2, 256 broilers were stunned using the same conditions as in Experiment 1. Measurements of pH, R-value, sarcomere length (SL), and fragmentation index (FI) were evaluated from the left breast fillets harvested at 0, 1, 2, and 6 h postmortem. Shear values (SV) were determined using the right fillets harvested at the same four postmortem times and aged on ice until 24 h. No significant difference in breast muscle pH value was observed at 0, 2, and 6 h postmortem. However, CO2-stunned fillets had significantly higher pH values than the ES fillets at 1 h postmortem. Carbon dioxide produced greater R values than electricity at 2 and 6 h. Sarcomere length, FI, and SV were not significantly different at any time tested. These data suggest that CO2 stunning reduced carcass damage but did not reduce the need for aging before deboning when compared to the electrical stunning method used.

Post-mortem redistribution of 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") in the rabbit. Part I: experimental approach after in vivo intravenous infusion.

PubMed

De Letter, Els A; Clauwaert, Karine M; Belpaire, Frans M; Lambert, Willy E; Van Bocxlaer, Jan F; Piette, Michel H A

2002-08-01

Post-mortem redistribution is known to influence blood and tissue levels of various drugs. An animal model was used in an attempt to elucidate this problem for the amphetamine analogue, 3,4-methylenedioxymethamphetamine (MDMA). Rabbits received 1 mg/kg MDMA intravenously (iv) and were killed 2 h later in order to simulate the state of complete distribution in the body. MDMA and 3,4-methylenedioxyamphetamine (MDA) concentrations were determined in blood, urine, bile, vitreous humour, and various tissues (eye globe walls, brain, cardiac muscle, lungs, liver, kidneys, iliopsoas muscle and adipose tissue) using a high pressure liquid chromatographic (HPLC) procedure with fluorescence detection. In the first group (control group, sampling immediately post mortem) considerable MDMA concentrations were found in the brain and both lungs. In addition, our data indicate the elimination of MDMA by hepatic biotransformation and excretion via the bile. When the animals were preserved either 24 or 72 h post mortem (second group), an increase of MDMA and MDA levels in the liver and the eye globe walls was noticed. In the lungs, on the other hand, they tended to decline as a function of increasing post-mortem interval. MDMA levels in cardiac and iliopsoas muscle were fairly comparable and remained stable up to 72 h after death. In the third group, ligation of the large vessels around the heart took place immediately post mortem, but significant differences in blood and tissue MDMA concentrations between rabbits of group 2 and 3 could not be demonstrated. We therefore conclude that post-mortem redistribution of MDMA at the cellular level (viz. by pure diffusion gradient from higher to lower concentrations) is more important than its redistribution via the vascular pathway. Finally, MDA levels were relatively low in all samples, thus indicating that this is not a major metabolite in the rabbit, at least within the first 2 h after administration.

Abnormal expression and functional characteristics of cyclic adenosine monophosphate response element binding protein in postmortem brain of suicide subjects.

PubMed

Dwivedi, Yogesh; Rao, Jagadeesh Sridhara; Rizavi, Hooriyah S; Kotowski, Jacek; Conley, Robert R; Roberts, Rosalinda C; Tamminga, Carol A; Pandey, Ghanshyam N

2003-03-01

Cyclic adenosine monophosphate response element binding protein (CREB) is a transcription factor that, on phosphorylation by protein kinases, is activated, and in response, regulates the transcription of many neuronally expressed genes. In view of the recent observations that catalytic properties and/or expression of many kinases that mediate their physiological responses through the activation of CREB are altered in the postmortem brain of subjects who commit suicide (hereafter referred to as suicide subjects), we examined the status of CREB in suicidal behavior. These studies were performed in Brodmann area (BA) 9 and hippocampus obtained from 26 suicide subjects and 20 nonpsychiatric healthy control subjects. Messenger RNA levels of CREB and neuron-specific enolase were determined in total RNA by means of quantitative reverse transcriptase-polymerase chain reaction. Protein levels and the functional characteristics of CREB were determined in nuclear fractions by means of Western blot and cyclic adenosine monophosphate response element (CRE)-DNA binding activity, respectively. In the same nuclear fraction, we determined the catalytic activity of cyclic adenosine monophosphate-stimulated protein kinase A by means of enzymatic assay. We observed a significant reduction in messenger RNA and protein levels of CREB, CRE-DNA binding activity, and basal and cyclic adenosine monophosphate-stimulated protein kinase A activity in BA 9 and hippocampus of suicide subjects, without any change in messenger RNA levels of neuron-specific enolase in BA 9. Except for protein kinase A activity, changes in CREB expression and CRE-DNA binding activity were present in all suicide subjects, irrespective of diagnosis. These changes were unrelated to postmortem intervals, age, sex, or antidepressant treatment. Given the significance of CREB in mediating various physiological functions through gene transcription, our results of decreased expression and functional characteristics of CREB in postmortem brain of suicide subjects suggest that CREB may play an important role in suicidal behavior.

Suprapubic track pressure and force--deformation measurements in a (live) human subject and in animal models post-mortem.

PubMed

Coveney, V A; Gepi-Attee, S; Gröver, D; Painter, D

2001-01-01

Tests have been performed on animal models shortly post-mortem and on a healthy human subject in order to obtain estimates of the forces which act on suprapubic urinary catheters and similar devices and to develop an abdominal wall simulator. Such data and test methods are required for the systematic design of suprapubic devices because of the dual need to maintain the functionality of devices and to avoid excessive pressure on soft body tissue which could lead to ischaemia and in turn necrosis. In the post-mortem animal models, electrical excitation was applied to the abdominal wall in order to stimulate muscle activity. Two types of transducers were used: a soft membrane transducer (SMT) for pressure measurement and novel instrumented 'tongs' to determine indentation stiffness characteristics in the suprapubic track or artificial pathway created for a device. The SMT has been extensively used in the urethras and bladders of human subjects while the tongs were built specifically for these tests. Only the well-established SMT was used with the human subject; a peak pressure of 22 kPa was obtained. In the animal models the pressure profile given by the SMT had a peak whose position corresponded well with the estimated location of the rectus muscle measured on the fixed tissue section. The peak value was 5.5 kPa, comparable with values likely to cause necrosis if maintained for more than 1 day. Remarkably consistent indentation stiffness values were obtained with the instrumented tongs; all values were close to 0.45 N/mm (33 kPa/mm).

Postmortem computed tomography in victims of military air mishaps: radiological-pathological correlation of CT findings.

PubMed

Levy, Gad; Goldstein, Liav; Blachar, Arye; Apter, Sara; Barenboim, Erez; Bar-Dayan, Yaron; Shamis, Ari; Atar, Eli

2007-10-01

A thorough medical inquiry is included in every aviation mishap investigation. While the gold standard of this investigation is a forensic pathology examination, numerous reports stress the important role of computed tomography in the postmortem evaluation of trauma victims. To characterize the findings identified by postmortem CT and compare its performance to conventional autopsy in victims of military aviation mishaps, we analyzed seven postmortem CT examinations. Musculoskeletal injuries accounted for 57.8% of the traumatic findings identified by postmortem CT. The most frequent findings were fractures of the rib (47%), skull (9.6%) and facial bones (8.6%). Abnormally located air accounted for 24% of findings, for which CT was superior (3.5% detected by autopsy, 100% by postmortem CT, P < 0.001). The performance of autopsy in detecting injuries was superior (autopsy detected 85.8% of all injuries, postmortem CT detected 53.9%, P < 0.001), especially in the detection of superficial lesions (100% detected by autopsy, 10.5% by postmortem CT, P < 0.001) and solid organ injuries (100% by autopsy, 18.5% by postmortem CT, P < 0.001). Performance in the detection of musculoskeletal injuries was similar (91.3% for autopsy, 90.3% for postmortem CT, P = not significant). Postmortem CT and autopsy have distinct performance profiles, and although the first cannot replace the latter it is a useful complementary examination.

[Biochemical measurements of glucose metabolism in relation to cause of death and postmortem effects].

PubMed

Kernbach, G; Püschel, K; Brinkmann, B

1986-01-01

This study was performed to examine the relationship between postmortem biochemical values and cause of death. The follow samples were taken from 399 corpses: cerebrospinal fluid (CSF; n = 376, suboccipital), blood (n = 158, femoral vein), and urine (n = 101, at autopsy). (See Table 1 for causes of death) All samples were stored at -80 degrees C. A further 100 samples of blood were later taken and stored at +4 degrees C before testing. Biochemical determinations made were: glucose in CSF, blood, and urine (hexokinase method); lactate (LDH/GPT) and free acetone (HS-gas chromatography) in CSF; hemoglobin A1 in blood (microcolumn technique). In 34 cases fatal diabetic coma was considered verified by morphological and chemical findings. One hundred cases of sudden cardiac death were chosen as the main control group. In 32 of the 34 cases defined above, the value of the formula of Traub (glucose + lactate in CSF) exceeded 415 mg/dl. It is not influenced significantly by hyperglycemia or hyperlactatemia due to factors other than diabetes (i.e., carbon monoxide, asphyxia). After death the value rose till the 30th hpm, then remained stable for at least 1 week. Fatal coma was defined as the ketoacidotic form if free acetone in CSF ranged above 21 mg/l. In these cases, CSF glucose and free acetone correlated positively. Hemoglobin A1 remained stable after death. Its amount was independent from postmortem blood glucose, postmortem interval and total hemoglobin. Furthermore, the manner of storage (-80 degrees or +4 degrees C) had no significant influence on its values. In 29 of 34 cases of fatal coma, Hb A1 exceeded 12.1%. Analysis of urine glucose showed elevated levels (over 500 mg/dl) in diabetic comas. On conclusion, fatal diabetic coma seems indicated as the cause of death if measured values of postmortem biochemistry exceed the following limits: CSF-Traub 415 mg/dl, free acetone (CSF) 21 mg/l; Hb A1 12.1%; urine glucose 500 mg/dl. Most important are the Traub formula and hemoglobin A1. Usually, in fatal coma both values are elevated. If both of them are normal, diabetic coma can nearly be excluded. Combined evaluation of all values is absolutely necessary. Morphology must also always be taken into account. Consequently, a diagnosis of fatal coma can be obtained by a process of elimination.

Basolateral amygdala volume and cell numbers in major depressive disorder: a postmortem stereological study.

PubMed

Rubinow, Marisa J; Mahajan, Gouri; May, Warren; Overholser, James C; Jurjus, George J; Dieter, Lesa; Herbst, Nicole; Steffens, David C; Miguel-Hidalgo, Jose J; Rajkowska, Grazyna; Stockmeier, Craig A

2016-01-01

Functional imaging studies consistently report abnormal amygdala activity in major depressive disorder (MDD). Neuroanatomical correlates are less clear: imaging studies have produced mixed results on amygdala volume, and postmortem neuroanatomic studies have only examined cell densities in portions of the amygdala or its subregions in MDD. Here, we present a stereological analysis of the volume of, and the total number of, neurons, glia, and neurovascular (pericyte and endothelial) cells in the basolateral amygdala in MDD. Postmortem tissues from 13 subjects with MDD and 10 controls were examined. Sections (~15/subject) taken throughout the rostral-caudal extent of the basolateral amygdala (BLA) were stained for Nissl substance and utilized for stereological estimation of volume and cell numbers. Results indicate that depressed subjects had a larger lateral nucleus than controls and a greater number of total BLA neurovascular cells than controls. There were no differences in the number or density of neurons or glia between depressed and control subjects. These findings present a more detailed picture of BLA cellular anatomy in depression than has previously been available. Further studies are needed to determine whether the greater number of neurovascular cells in depressed subjects may be related to increased amygdala activity in depression.

The price of the precautionary principle: cost-effectiveness of BSE intervention strategies in The Netherlands.

PubMed

Benedictus, A; Hogeveen, H; Berends, B R

2009-06-01

Since 1996, bovine spongiform encephalopathy (BSE) in cattle has been linked to a new variant of Creutzfeldt-Jakob disease (vCJD), a fatal brain disease in man. This paper assessed the cost-effectiveness of BSE control strategies instituted by the European Commission. In a Monte Carlo simulation model, a non-intervention baseline scenario was compared to three intervention strategies: removal of specified risk materials from slaughter animals, post-mortem testing for BSE and the culling of feed and age cohorts of BSE cases. The food risk in the baseline scenario ranged from 16.98 lost life years in 2002 to 2.69 lost life years in 2005. Removing specified risk materials removal practices, post-mortem testing and post-mortem testing plus cohort culling reduced this risk with 93%, 82.7% and 83.1%. The estimated cost-effectiveness of all BSE measures in The Netherlands ranged from 4.3 million euros per life year saved in 2002 to 17.7 million euros in 2005. It was discussed that the cost-effectiveness of BSE control strategies will further deviate from regular health economics thresholds as BSE prevalence and incidence declines.

[Legal aspects of post-mortem radiology in the Netherlands].

PubMed

Venderink, W; Dute, J C J

2016-01-01

In the Netherlands, the application of post-mortem radiology (virtual autopsy) is on the rise. Contrary to conventional autopsy, with post-mortem radiology the body remains intact. There is uncertainty concerning the legal admissibility of post-mortem radiology, since the Dutch Corpse Disposal Act does not contain any specific regulations for this technique. Autopsy and post-mortem radiology differ significantly from a technical aspect, but these differences do not have far-reaching legal consequences from a legal perspective. Even though the body remains intact during post-mortem radiology, the bodily integrity of a deceased person is breached if it would be applied without previously obtained consent. This permission can only be obtained after the relatives are fully informed about the proposed activity. In this respect, it is not relevant which technique is used, be it post-mortem radiology or autopsy. Therefore, the other legal conditions for post-mortem radiology are essentially identical to those for autopsy.

DNA degradation and genetic analysis of empty puparia: genetic identification limits in forensic entomology.

PubMed

Mazzanti, Morena; Alessandrini, Federica; Tagliabracci, Adriano; Wells, Jeffrey D; Campobasso, Carlo P

2010-02-25

Puparial cases are common remnants of necrophagous flies in crime investigations. They usually represent the longest developmental time and, therefore, they can be very useful for the estimation of the post-mortem interval (PMI). However, before any PMI estimate, it is crucial to identify the species of fly eclosed from each puparium associated with the corpse. Morphological characteristics of the puparium are often distinctive enough to permit a species identification. But, even an accurate morphological analysis of empty puparia cannot discriminate among different species of closely related flies. Furthermore, morphological identification may be impossible if the fly puparia are poorly preserved or in fragments. This study explores the applicability of biomolecular techniques on empty puparia and their fragments for identification purposes. A total of 63 empty puparia of necrophagous Diptera resulting from forensic casework were examined. Samples were divided into three groups according to size, type and time of eclosion in order to verify whether the physical characteristics and puparia weathering can influence the amount of DNA extraction. The results suggest that a reliable genetic identification of forensically important flies may also be performed from empty puparia and/or their fragments. However, DNA degradation can deeply compromise the genetic analysis since the older the fly puparia, the smaller are the amplified fragments. 2009 Elsevier Ireland Ltd. All rights reserved.

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

PubMed

Dogan, Kamil Hakan; Unaldi, Mustafa; Demirci, Serafettin

2016-09-01

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. © 2016 American Academy of Forensic Sciences.

State-of-the-art of bone marrow analysis in forensic toxicology: a review.

PubMed

Cartiser, Nathalie; Bévalot, Fabien; Fanton, Laurent; Gaillard, Yvan; Guitton, Jérôme

2011-03-01

Although blood is the reference medium in the field of forensic toxicology, alternative matrices are required in case of limited, unavailable or unusable blood samples. The present review investigated the suitability of bone marrow (BM) as an alternative matrix to characterize xenobiotic consumption and its influence on the occurrence of death. Basic data on BM physiology are reported in order to highlight the specificities of this matrix and their analytical and toxicokinetic consequences. A review of case reports, animal and human studies involving BM sample analysis focuses on the various parameters of interpretation of toxicological results: analytic limits, sampling location, pharmacokinetics, blood/BM concentration correlation, stability and postmortem redistribution. Tables summarizing the analytical conditions and quantification of 45 compounds from BM samples provide a useful tool for toxicologists. A specific section devoted to ethanol shows that, despite successful quantification, interpretation is highly dependent on postmortem interval. In conclusion, BM is an interesting alternative matrix, and further experimental data and validated assays are required to confirm its great potential relevance in forensic toxicology.

Validity of Postmortem Glycated Hemoglobin to Determine Status of Diabetes Mellitus in Corneal Donors.

PubMed

Soper, Mark C; Marcovina, Santica M; Hoover, Caroline K; Calhoun, Peter M; McCoy, Kristen E; Stoeger, Christopher G; Schmidt, Gregory A; Arafah, Baha M; Price, Marianne O; Szczotka-Flynn, Loretta B; Lass, Jonathan H

2017-08-01

To examine the stability of postmortem glycated hemoglobin (HbA1c) measurement and its relationship to premortem glycemia. Postmortem blood samples were obtained from 32 donors (8 known diabetic) and shipped on ice to a central laboratory to examine the stability of HbA1c measurements during the first 9 postmortem days. Thirty-nine other suspected diabetic donors underwent comparison of premortem and postmortem HbA1c measurements. Postmortem HbA1c measurements remained stable after 9 postmortem days (all measurements within ±0.2% from baseline with a mean difference of 0.02% ± 0.10%). Of the premortem measurements obtained within 90 days before death, 79% were within ±1.0% of the postmortem measurements compared with 40% for measurements more than 90 days apart. Three of the postmortem HbA1c measurements exceeded 6.5% (considered a threshold for diabetes diagnosis), although the medical histories did not indicate any previous diabetes diagnosis. Postmortem HbA1c testing is feasible with current eye bank procedures and is reflective of glycemic control of donors during 90 days before death. HbA1c testing could potentially be a useful adjunct to review of the medical history and records for donor assessment for endothelial keratoplasty suitability and long-term graft success.

[Establishment of the Mathematical Model for PMI Estimation Using FTIR Spectroscopy and Data Mining Method].

PubMed

Wang, L; Qin, X C; Lin, H C; Deng, K F; Luo, Y W; Sun, Q R; Du, Q X; Wang, Z Y; Tuo, Y; Sun, J H

2018-02-01

To analyse the relationship between Fourier transform infrared （FTIR） spectrum of rat's spleen tissue and postmortem interval （PMI） for PMI estimation using FTIR spectroscopy combined with data mining method. Rats were sacrificed by cervical dislocation, and the cadavers were placed at 20 ℃. The FTIR spectrum data of rats' spleen tissues were taken and measured at different time points. After pretreatment, the data was analysed by data mining method. The absorption peak intensity of rat's spleen tissue spectrum changed with the PMI, while the absorption peak position was unchanged. The results of principal component analysis （PCA） showed that the cumulative contribution rate of the first three principal components was 96%. There was an obvious clustering tendency for the spectrum sample at each time point. The methods of partial least squares discriminant analysis （PLS-DA） and support vector machine classification （SVMC） effectively divided the spectrum samples with different PMI into four categories （0-24 h, 48-72 h, 96-120 h and 144-168 h）. The determination coefficient （ R ²） of the PMI estimation model established by PLS regression analysis was 0.96, and the root mean square error of calibration （RMSEC） and root mean square error of cross validation （RMSECV） were 9.90 h and 11.39 h respectively. In prediction set, the R ² was 0.97, and the root mean square error of prediction （RMSEP） was 10.49 h. The FTIR spectrum of the rat's spleen tissue can be effectively analyzed qualitatively and quantitatively by the combination of FTIR spectroscopy and data mining method, and the classification and PLS regression models can be established for PMI estimation. Copyright© by the Editorial Department of Journal of Forensic Medicine.

Sensitivity and specificity of real-time reverse transcription polymerase chain reaction, histopathology, and immunohistochemical labeling for the detection of Rift Valley fever virus in naturally infected cattle and sheep.

PubMed

Odendaal, Lieza; Fosgate, Geoffrey T; Romito, Marco; Coetzer, Jacobus A W; Clift, Sarah J

2014-01-01

Real-time reverse transcription polymerase chain reaction (real-time RT-PCR), histopathology, and immunohistochemical labeling (IHC) were performed on liver specimens from 380 naturally infected cattle and sheep necropsied during the 2010 Rift Valley fever (RVF) epidemic in South Africa. Sensitivity (Se) and specificity (Sp) of real-time RT-PCR, histopathology, and IHC were estimated in a latent-class model using a Bayesian framework. The Se and Sp of real-time RT-PCR were estimated as 97.4% (95% confidence interval [CI] = 95.2-98.8%) and 71.7% (95% CI = 65-77.9%) respectively. The Se and Sp of histopathology were estimated as 94.6% (95% CI = 91-97.2%) and 92.3% (95% CI = 87.6-95.8%), respectively. The Se and Sp of IHC were estimated as 97.6% (95% CI = 93.9-99.8%) and 99.4% (95% CI = 96.9-100%), respectively. Decreased Sp of real-time RT-PCR was ascribed to cross-contamination of samples. Stratified analysis of the data suggested variations in test accuracy with fetuses and severely autolyzed specimens. The Sp of histopathology in fetuses (83%) was 9.3% lower than the sample population (92.3%). The Se of IHC decreased from 97.6% to 81.5% in the presence of severe autolysis. The diagnostic Se and Sp of histopathology was higher than expected, confirming the value of routine postmortem examinations and histopathology of liver specimens. Aborted fetuses, however, should be screened using a variety of tests in areas endemic for RVF, and results from severely autolyzed specimens should be interpreted with caution. The most feasible testing option for countries lacking suitably equipped laboratories seems to be routine histology in combination with IHC.

Study on the apoptosis mediated by cytochrome c and factors that affect the activation of bovine longissimus muscle during postmortem aging.

PubMed

Zhang, Jiaying; Yu, Qunli; Han, Ling; Chen, Cheng; Li, Hang; Han, Guangxing

2017-06-01

This study investigates whether bovine longissimus muscle cell apoptosis occurs during postmortem aging and whether apoptosis is dependent on the mitochondria pathway. This study also determines the apoptosis process mediated by cytochrome c after its release from mitochondria and the factors that affect the activation processes. Results indicate that apoptotic nuclei were detected at 12 h postmortem. Cytochrome c release from the mitochondria to the cytoplasm activated the caspase-9 and caspase-3 at early postmortem aging and the activation of caspase-9 occurs before the activation of caspase-3. The pH level decreased during the first 48 h postmortem, whereas the mitochondria membrane permeability increased from 6 to 12 h. Results demonstrate that an apoptosis process of bovine muscle occurred during postmortem aging. Apoptosis was dependent on the mitochondria pathway and occurred at early postmortem aging. Increased mitochondria membrane permeability and low pH are necessary conditions for the release of cytochrome c during postmortem aging.

Time averaging and stratigraphic disorder of molluscan assemblages in the Holocene sediments in the NE Adriatic (Piran)

NASA Astrophysics Data System (ADS)

Tomasovych, Adam; Gallmetzer, Ivo; Haselmair, Alexandra; Kaufman, Darrell S.; Zuschin, Martin

2016-04-01

Stratigraphic changes in temporal resolution of fossil assemblages and the degree of their stratigraphic mixing in the Holocene deposits are of high importance in paleoecology, conservation paleobiology and paleoclimatology. However, few studies quantified downcore changes in time averaging and in stratigraphic disorder on the basis of dating of multiple shells occurring in individual stratigraphic layers. Here, we investigate downcore changes in frequency distribution of postmortem ages of the infaunal bivalve Gouldia minima in two, ~150 cm-thick piston cores (separated by more than 1 km) in the northern Adriatic Sea, close to the Slovenian city Piran at a depth of 24 m. We use radiocarbon-calibrated amino acid racemization to obtain postmortem ages of 564 shells, and quantify age-frequency distributions in 4-5 cm-thick stratigraphic intervals (with 20-30 specimens sampled per interval). Inter-quartile range for individual 4-5 cm-thick layers varies between 850 and 1,700 years, and range encompassing 95% of age data varies between 2,000 and 5,000 years in both cores. The uppermost sediments (20 cm) are age-homogenized and show that median age of shells is ~700-800 years. The interval between 20 and 90 cm shows a gradual increase in median age from ~2,000 to ~5,000 years, with maximum age ranging to ~8,000 years. However, the lowermost parts of both cores show a significant disorder, with median age of 3,100-3,300 years. This temporal disorder implies that many shells were displaced vertically by ~1 m. Absolute and proportional abundance of the bivalve Gouldia minima strongly increases towards the top of the both cores. We hypothesize that such increase in abundance, when coupled with depth-declining reworking, can explain stratigraphic disorder because numerically abundant young shells from the top of the core were more likely buried to larger sediment depths than less frequent shells at intermediate sediment depths.

Diagnosis of Vitality in Skin Wounds in the Ligature Marks Resulting From Suicide Hanging.

PubMed

Legaz Pérez, Isabel; Falcón, Maria; Gimenez, M; Diaz, F Martínez; Pérez-Cárceles, M D; Osuna, E; Nuno-Vieira, D; Luna, A

2017-09-01

Ascertaining the vital origin of skin wounds is one of the most challenging problems in forensic pathology. The forensic literature describes biomarkers and methods for differentiating vital and postmortem wounds, although no clear conclusions have been reached. The aim of this study was to characterize human vital wounds by analyzing the concentrations of metallic ions and the expression of P-selectin and cathepsin D in skin wounds in the ligature marks in a cohort of suicidal hangings for which vitality was previously demonstrated.A total of 71 skin wounds were analyzed within a postmortem interval of 19 to 36 hours. The concentration of Fe, Zn, Mg, and Ca and the expression of P-selectin and cathepsin D were analyzed together and separately. The majority of autopsied suicidal hangings were men (86%) with complete hanging mode (60.7%) in which there was a high frequency of subcutaneous injuries (78.3%). High concentrations of Ca and Mg compared with Fe and Zn were found. Ca and Zn concentrations decreased, and Fe concentration increased with the seriousness of the injury. A high percentage of moderately negative expression of both proteins was correlated with subcutaneous injury and low or medium concentrations of Fe.In conclusion, the joint study of metallic ions and proteins allows to characterize and to differentiate an injured vital wound of noninjured skin, especially when the damage in the tissue affects to the majority of the structures of the skin, but these results will need to be complemented with other biomarkers in time-controlled samples to further help in the differentiation of vital and postmortem wounds.

Metabolic half-life of somatostatin and peptidase activities are altered in Alzheimer's disease.

PubMed

Weber, S J; Louis, R B; Trombley, L; Bissette, G; Davies, P; Davis, T P

1992-01-01

Several reports have described decreased immunoreactive somatostatin levels in specific regions of post-mortem brain tissue from patients diagnosed with senile dementia of the Alzheimer type (SDAT). In an attempt to determine if the metabolism of somatostatin is also altered as a result of SDAT, we examined the regional metabolic half-life of somatostatin-28 (SS-28) and somatostatin-14 (SS-14). The activity of the following peptidases was also determined: neutral endopeptidase E.C. 3.4.24.11; metalloendopeptidase E.C. 3.4.24.15; carboxypeptidase E (E.C. 3.4.17.10); and trypsin-like serine protease. The metabolic half-life of SS-28 was significantly reduced in post-mortem Brodmann Area 22 of SDAT tissue. This decrease in SS-28 metabolic half-life was correlated with a significant increase in trypsin-like serine protease activity in the same SDAT brain region. The formation rate of SS-14 from SS-28 incubated with Brodmann Area 22 homogenates was also increased in SDAT tissues as compared to controls. A regional variation in neutral endopeptidase E.C. 3.4.24.11 was also noted in both controls and SDAT samples. Although postmortem intervals of samples varied significantly, no effect was seen on any biochemical parameter measured. Results from this study provide evidence that a correlation can be made between changes in metabolic half-life somatostatin and alterations in neuropeptidase activities due to SDAT. As these data show alterations in both proteolytic metabolism and peptidase activities, many other biologically active peptide substrates could also be affected in SDAT.

Detection of Metabolism Function of Microbial Community of Corpses by Biolog-Eco Method.

PubMed

Jiang, X Y; Wang, J F; Zhu, G H; Ma, M Y; Lai, Y; Zhou, H

2016-06-01

To detect the changes of microbial community functional diversity of corpses with different postmortem interval （PMI） and to evaluate forensic application value for estimating PMI. The cultivation of microbial community from the anal swabs of a Sus scrofa and a human corpse placed in field environment from 0 to 240 h after death was performed using the Biolog-Eco Microplate and the variations of the absorbance values were also monitored. Combined with the technology of forensic pathology and flies succession, the metabolic characteristics and changes of microbial community on the decomposed corpse under natural environment were also observed. The diversity of microbial metabolism function was found to be negatively correlated with the number of maggots in the corpses. The freezing processing had the greatest impact on average well color development value at 0 h and the impact almost disappeared after 48 h. The diversity of microbial metabolism of the samples became relatively unstable after 192 h. The principal component analysis showed that 31 carbon sources could be consolidated for 5 principal components （accumulative contribution ratio >90%）.The carbon source tsquare-analysis showed that N -acetyl- D -glucosamine and L -serine were the dominant carbon sources for estimating the PMI （0=240 h） of the Sus scrofa and human corpse. The Biolog-Eco method can be used to reveal the metabolic differences of the carbon resources utilization of the microbial community on the corpses during 0-240 h after death, which could provide a new basis for estimating the PMI. Copyright© by the Editorial Department of Journal of Forensic Medicine

Assessment of the bacterial impact on the post-mortem formation of zinc protoporphyrin IX in pork meat.

PubMed

Ghadiri Khozroughi, Amin; Kroh, Lothar W; Schlüter, Oliver; Rawel, Harshadrai

2018-08-01

The post-mortem accumulation of the heme biosynthesis metabolite zinc protoporphyrin IX (ZnPP) in porcine muscle is associated with both a meat-inherent and a bacterial enzymatic reaction during meat storage. To estimate the bacterial impact on ZnPP formation, meat and meat-like media were investigated by HPLC-FLD (and MALDI-TOF-MS) after inoculation with a representative microorganism (P. fluorescens). Results indicate the principal ability of meat-inherent bacteria to form ZnPP in meat extracts and meat-like media, but not on the meat muscle. Thus it was concluded that the ZnPP formation in meat is due to a meat-inherent enzymatic reaction induced by porcine ferrochelatase (FECH), while the bacterial (FECH) induced reaction seems to be not significant. Copyright © 2018. Published by Elsevier Ltd.

Characterization and microbial analysis of first recorded observation of Conicera similis Haliday (Diptera: Phoridae) in forensic decomposition study in Romania.

PubMed

Iancu, Lavinia; Junkins, Emily N; Purcarea, Cristina

2018-05-03

The identification of necrophagous insect diversity and dynamics has forensic significance for postmortem interval estimation specific to burial. Few studies regarding the necrophagous entomofauna from buried remains have been performed to date. In contrast to the exposed carcasses, the accessibility of soil to insects is limited due to burial depth and is dependent on soil type. This study highlights the colonization behavior of Conicera similis (Haliday 1833) (Diptera: Phoridae) during carcass decomposition, a previously unobserved taxon in Romania. Adult and larvae specimens were collected from rat (Rattus norvegicus) carcasses buried at 40 cm depth in an urban park environment in June 2016 during active decomposition and their presence and activity period was correlated with the environmental parameters variation. Bacterial diversity from C. similis female adult and larvae specimens was determined via 16S rRNA gene Illumina sequencing to further characterize these commonly encountered and forensically important necrophagous insects. This report signals the easternmost geographical location in Europe (Bucharest, Romania) of C. similis to date. Copyright © 2018 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Cadaver wrapping and arrival performance of adult flies in an oil palm plantation in northern Peninsular Malaysia.

PubMed

Ahmad, Azwani; Ahmad, Abu Hassan; Dieng, Hamady; Satho, Tomomitsu; Ahmad, Hamdan; Aziz, Al Thbyani; Boots, Michael

2011-11-01

There is accumulating evidence that criminals wrap dead bodies in an attempt to conceal evidence. To anticipate the forensic implications of this phenomenon, we examined whether flies that are naturally associated with cadavers exhibit a delay in attendance or differ in species composition and abundance patterns because of the presence of wrapping material. Wrapped and exposed carcasses of dead monkeys placed in an oil plantation in Kedah, Malaysia, were visited over 50 d. On daily visits to each of the six carcasses, visiting adult flies were sampled using hand nets. Flies of 12 families were encountered. Calliphoridae (Chrysomya rufifacies Macquart and C. megacephala (F.) was the most prevalent family, followed by Sphaeroceridae. Some families tended to be more abundant in WRCs (i.e., Calliphoridae, Muscidae, and Phoridae), whereas others (i.e., Piophilidae, Sepsidae, and Psychodidae) were more prevalent in exposed carcasses. Wrapping delayed the arrival of all fly species encountered, with delays varying from 1 to 13 d depending on species. Wrapping did not affect species composition of flies, but prolong the occurrence of some species. The results of the current study emphasize the need to take into consideration the presence of a wrap when estimating postmortem interval.

Description of Larval Instars To Fill a Gap in Forensic Entomology: The Larvae of Paralucilia pseudolyrcea (Diptera: Calliphoridae).

PubMed

Da Silva, S M; Vairo, K P; Moura, M O

2018-05-04

A fundamental assumption of forensic entomology for estimating the postmortem interval is that insect species are accurately identified, which depends on diagnostic morphological characters. Larvae of the blow fly Paralucilia pseudolyrcea (Mello, 1969) (Diptera: Calliphoridae) were sampled from four corpses in the state of Paraná, Brazil, but despite the forensic importance of this species, morphological data for the identification of its larval instars are lacking, limiting its usefulness in such cases. Thus, the main goal of this study was to describe the larval instars of P. pseudolyrcea. The material was obtained from a colony established by larvae collected from a corpse of a murder case. Overall, the distribution of spines is a key character for identifying this species in the first, second and third instars. Other characteristics, such as the presence of an accessory oral sclerite, the small cirri, the number of lobes of the anterior spiracle and the morphology of posterior spiracles, separates P. pseudolyrcea from other necrophagous blow flies. The detailed morphological description provided here facilitates the identification of larval instars of P. pseudolyrcea and their differentiation from those of other calliphorid species.

Dipteran Diversity and Ecological Succession on Dead Pigs in Contrasting Mountain Habitats of Chiapas, Mexico.

PubMed

Mañas-Jordá, Saray; León-Cortés, Jorge L; García-García, María D; Caballero, Ubaldo; Infante, Francisco

2018-01-10

A comparative study of Diptera communities associated with pig carcasses was carried out in urban and natural settings in tropical mountain habitats of Southern Mexico. Schoenly-type traps were used to set out pig carcasses during 68 d of sampling effort. In total, 1,703 adult Diptera specimens were collected in both localities combined, and recording a total of 30 (morpho) species and 19 families. Compared to natural habitats, a significantly greater diversity in urban habitats, as well as a faster decomposition process of carcasses, was detected. Significant differences were also detected for the composition and structure of Dipteran communities between urban and natural sites. Dominant species of Calliphoridae for natural and urban habitats were represented by Compsomyiops spp. and Cochliomyia macellaria (Fabricius; Diptera: Calliphoridae), respectively. The properties of indicator species for urban and natural sites are discussed. Twenty Dipteran species were significantly associated to different decomposition stages. Such affinity would allow for estimating the post-mortem interval (PMI) in comparable situations. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Decomposition and dipteran succession in pig carrion in central Argentina: ecological aspects and their importance in forensic science.

PubMed

Horenstein, M Battán; Linhares, A Xavier; De Ferradas, B Rosso; García, D

2010-03-01

Data on the insect species associated with corpse decomposition are particularly important for estimation of the post-mortem interval (PMI) in forensic science because the PMI is based on the lifecycle and behaviour of necrophagous insects, among other measures. To determine the dipteran succession on pig carrion, four experiments, one in each season, were carried out during 2004 in a rural area of Córdoba, central Argentina. Two pigs (Sus scrofa L.) were used in each of the four experiments. At each time-point one pig was placed in the shade and the other under direct sunlight. Insects were collected daily during the first 4 weeks and thereafter every 2 or 3 days. Five stages of decomposition were observed and a total of 24 710 adult specimens were collected, belonging to the following eight families of Diptera: Calliphoridae; Muscidae; Sarcophagidae; Phoridae; Piophilidae; Fanniidae; Sphaeroceridae, and Anthomyiidae. All Calliphoridae collected in this study were considered to be of potential forensic importance because of their necrophagous behaviour and because their immature stages use carrion as a food source. Other species, such as Musca domestica L. and Ophyra aenescens (Wiedemann), were also considered to represent potential forensic indicators.

Effects of temperature and diet on black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae), development.

PubMed

Harnden, Laura M; Tomberlin, Jeffery K

2016-09-01

The black soldier fly, Hermetia illucens, is recognised for its use in a forensic context as a means for estimating the time of colonisation and potentially postmortem interval of decomposing remains. However, little data exist on this species outside of its use in waste management. This study offers a preliminary assessment of the development, and subsequent validation, of H. illucens. Larvae of H. illucens were reared at three temperatures (24.9°C, 27.6°C and 32.2°C) at 55% RH on beef loin muscle, pork loin muscle and a grain-based diet (control). Each of the temperatures and diets were found to significantly (P<0.05) affect all stages of immature growth except for pupation time. Overall, those reared on the pork diet required on average ≈23.1% and ≈139.7% more degree hours to complete larval development than those reared on the beef and grain-based diets, respectively. Larvae reared at 27.6°C and 32.2°C required on average ≈8.7% more degree hours to complete development and had a final larval weight ≈30% greater than larvae reared at 24.9°C. The validity of the laboratory larval length and weight data sets was assessed via estimating the age of field-reared larvae. Grain-diet data lacked accuracy when used to estimate larval age in comparison to estimates made with beef and pork-diet data, which were able to predict larval age for ≈55.6% and ≈88.9% of sampling points, respectively, when length and weight data were used in conjunction. Field-reared larval sizes exceeded the maximum observed under laboratory conditions in almost half of the samples, which reduced estimate accuracy. Future research should develop additional criteria for identifying development of each specific instar, which may aid in improving the accuracy and precision of larval age estimates for this species. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Perinatal postmortems: what is important to parents and how do they decide?

PubMed

Breeze, Andrew C G; Statham, Helen; Hackett, Gerald A; Jessop, Flora A; Lees, Christoph C

2012-03-01

Falling consent rates for postmortems, regardless of age of death, have been widely reported in recent years. The aim of this study was to explore parental attitudes to, and decision-making about, a perinatal postmortem after termination for fetal abnormality, late miscarriage, or stillbirth. A prospective self-completion questionnaire was given to 35 women and their partners. The participants had experienced second or third trimester pregnancy loss in a single fetal medicine and delivery unit in the United Kingdom and were making decisions about having a postmortem. They were asked to complete a questionnaire about their attitudes to, and expectations of, a perinatal postmortem. Thirty-one questionnaires were received from parents of 17 babies (49% of those asked; 16 from mothers, 15 from fathers). Parents of nine babies (53%) said they would agree to a full postmortem, of three babies to a limited postmortem, and of four babies to an external examination only; one couple were undecided. The most important issues for the parents in this study that related to their decisions about a postmortem centered on the need for information, both for future planning and about what had happened. Moderately important issues related to altruism, which is, improving medical knowledge and helping other parents experiencing similar bereavement. Among the lowest scoring issues were potential barriers, such as concerns about cultural or religious acceptability of a postmortem, funeral delays, and what would happen to the baby's body. Bereaved parents who participated in this study, where postmortem consent rates were relatively high, thought that their need for knowledge eclipsed assumed barriers when deciding whether or not to have a postmortem for their baby. © 2012, Copyright the Authors. Journal compilation © 2012, Wiley Periodicals, Inc.

Forensic applications of 14C at CIRCE

NASA Astrophysics Data System (ADS)

Marzaioli, F.; Fiumano, V.; Capano, M.; Passariello, I.; Cesare, N. De.; Terrasi, F.

2011-12-01

The decreasing trend of the radiocarbon pulse produced during the atmospheric tests of nuclear weapons (bomb-carbon) coupled with high sensitivity accelerator mass spectrometry (AMS) measurements, drastically increased the precision of radiocarbon age determinations since the second part of the sixties, allowing the application of radiocarbon AMS to a wide range of studies previously not directly involving conventional radiocarbon dating (i.e. food authenticity, forensic, biochemistry). In the framework of authenticity evaluation of artworks, high precision radiocarbon ( 14C) AMS measurements (Δ R/ R < 0.3%) reduce the conventional uncertainty of the dating to few decades, allowing precise age estimation of materials containing carbon (C). The Centre for Isotopic Research on Cultural and Environmental heritage (CIRCE) during its activity on AMS 14C dating achieved high precision measurements opening the opportunity to these kinds of applications. This paper presents the main results obtained from radiocarbon measurements on a set of bone samples analyzed for the determination of the post-mortem interval in the framework of an unsolved case investigated by the Rome prosecutor office. The chronological characterization of the wooden support of the "Acerenza portrait" is also presented with the aim to evaluate its age and to further investigate the possibility to attribute this artwork to Leonardo da Vinci. Bomb- 14C dating on the lipid and collagen fractions of bones allows the evaluation of the year of the death of the individuals by means of ad hoc calibration data sheet with the typical few years precision and difference between collagen apparent age and the year of death appeared in agreement with the age of one individual estimated by dating of tooth collagen. Conventional radiocarbon dating on both wood and wood extracted cellulose leads to an estimation of the portrait wood board age (2σ) of 1459-1524 AD (57% relative probability), 1571-1631 AD interval (42% relative probability).and 1559-1563 AD (1% relative probability). These results attribute with the highest relative probability an age comprised within the life span of Leonardo (1452-1519) to the support.

9 CFR 381.76 - Post-mortem inspection, when required; extent; traditional, Streamlined Inspection System (SIS...

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Post-mortem inspection, when required... INSPECTION REGULATIONS Post Mortem Inspection; Disposition of Carcasses and Parts § 381.76 Post-mortem...) Inspection System and the New Turkey Inspection (NTI) System; rate of inspection. (a) A post-mortem...

9 CFR 381.76 - Post-mortem inspection, when required; extent; traditional, Streamlined Inspection System (SIS...

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Post-mortem inspection, when required... INSPECTION REGULATIONS Post Mortem Inspection; Disposition of Carcasses and Parts § 381.76 Post-mortem...) Inspection System and the New Turkey Inspection (NTI) System; rate of inspection. (a) A post-mortem...

9 CFR 381.76 - Post-mortem inspection, when required; extent; traditional, Streamlined Inspection System (SIS...

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Post-mortem inspection, when required... INSPECTION REGULATIONS Post Mortem Inspection; Disposition of Carcasses and Parts § 381.76 Post-mortem...) Inspection System and the New Turkey Inspection (NTI) System; rate of inspection. (a) A post-mortem...

9 CFR 381.76 - Post-mortem inspection, when required; extent; traditional, Streamlined Inspection System (SIS...

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Post-mortem inspection, when required... INSPECTION REGULATIONS Post Mortem Inspection; Disposition of Carcasses and Parts § 381.76 Post-mortem...) Inspection System and the New Turkey Inspection (NTI) System; rate of inspection. (a) A post-mortem...

Human decomposition and the reliability of a 'Universal' model for post mortem interval estimations.

PubMed

Cockle, Diane L; Bell, Lynne S

2015-08-01

Human decomposition is a complex biological process driven by an array of variables which are not clearly understood. The medico-legal community have long been searching for a reliable method to establish the post-mortem interval (PMI) for those whose deaths have either been hidden, or gone un-noticed. To date, attempts to develop a PMI estimation method based on the state of the body either at the scene or at autopsy have been unsuccessful. One recent study has proposed that two simple formulae, based on the level of decomposition humidity and temperature, could be used to accurately calculate the PMI for bodies outside, on or under the surface worldwide. This study attempted to validate 'Formula I' [1] (for bodies on the surface) using 42 Canadian cases with known PMIs. The results indicated that bodies exposed to warm temperatures consistently overestimated the known PMI by a large and inconsistent margin for Formula I estimations. And for bodies exposed to cold and freezing temperatures (less than 4°C), then the PMI was dramatically under estimated. The ability of 'Formulae II' to estimate the PMI for buried bodies was also examined using a set of 22 known Canadian burial cases. As these cases used in this study are retrospective, some of the data needed for Formula II was not available. The 4.6 value used in Formula II to represent the standard ratio of time that burial decelerates the rate of decomposition was examined. The average time taken to achieve each stage of decomposition both on, and under the surface was compared for the 118 known cases. It was found that the rate of decomposition was not consistent throughout all stages of decomposition. The rates of autolysis above and below the ground were equivalent with the buried cases staying in a state of putrefaction for a prolonged period of time. It is suggested that differences in temperature extremes and humidity levels between geographic regions may make it impractical to apply formulas developed in one region to any other region. These results also suggest that there are other variables, apart from temperature and humidity that may impact the rate of human decomposition. These variables, or complex of variables, are considered regionally specific. Neither of the Universal Formulae performed well, and our results do not support the proposition of Universality for PMI estimation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Time of death of victims found in cold water environment.

PubMed

Karhunen, Pekka J; Goebeler, Sirkka; Winberg, Olli; Tuominen, Markku

2008-04-07

Limited data is available on the application of post-mortem temperature methods to non-standard conditions, especially in problematic real life cases in which the body of the victim is found in cold water environment. Here we present our experience on two cases with known post-mortem times. A 14-year-old girl (rectal temperature 15.5 degrees C) was found assaulted and drowned after a rainy cold night (+5 degrees C) in wet clothing (four layers) at the bottom of a shallow ditch, lying in non-flowing water. The post-mortem time turned out to be 15-16 h. Four days later, at the same time in the morning, after a cold (+/- 0 degrees C) night, a young man (rectal temperature 10.8 degrees C) was found drowned in a shallow cold drain (+4 degrees C) wearing similar clothing (four layers) and being exposed to almost similar environmental and weather conditions, except of flow (7.7 l/s or 0.3 m/s) in the drain. The post-mortem time was deduced to be 10-12 h. We tested the applicability of five practical methods to estimate time of death. Henssge's temperature-time of death nomogram method with correction factors was the most versatile and gave also most accurate results, although there is limited data on choosing of correction factors. In the first case, the right correction factor was close to 1.0 (recommended 1.1-1.2), suggesting that wet clothing acted like dry clothing in slowing down body cooling. In the second case, the right correction factor was between 0.3 and 0.5, similar to the recommended 0.35 for naked bodies in flowing water.

The Accuracy of Estimated Total Test Statistics. Final Report.

ERIC Educational Resources Information Center

Kleinke, David J.

In a post-mortem study of item sampling, 1,050 examinees were divided into ten groups 50 times. Each time, their papers were scored on four different sets of item samples from a 150-item test of academic aptitude. These samples were selected using (a) unstratified random sampling and stratification on (b) content, (c) difficulty, and (d) both.…

Prevalence and financial effects of hydatidosis in cattle slaughtered in Birre-Sheleko and Dangila Abattoirs, Northwestern Ethiopia.

PubMed

Kebede, N; Gebre-Egziabher, Z; Tilahun, G; Wossene, A

2011-02-01

A cross-sectional survey of bovine hydatidosis was carried out on local zebu cattle slaughtered at Birre-Sheleko and Dangila Abattoirs from August 2007 to July 2008 to determine the prevalence and to estimate financial loss caused by the disease. Postmortem examination, hydatid cyst characterization and direct and indirect financial loss estimations were conducted. Out of the total of 521 animals examined (255 Birre-Sheleko and 266 Dangila), 79 (15.2%) were found harbouring one or more hydatid cyst. The prevalence of the disease between the two abattoirs was not significantly different (P > 0.05). The result obtained from postmortem examination indicated that a total of 112 visceral organs were found harbouring one or more hydatid cysts. The involvement of lung, liver, spleen and kidney was found to be 70.5%, 21.4%, 6.3% and 1.8% respectively. From the total of 224 cysts counted, 147 (65.6%), 29 (12.9%), 3 (1.3%) and 45 (20.1%) were small, medium, large and calcified cysts respectively, and 114 (50.9%) and 65 (29%) were sterile and fertile cysts respectively. Viability rate of 47.7%, all from the lungs, and higher liver calcification rate were observed. The annual financial loss from organ condemnation and carcass weight loss due to bovine hydatidosis at Birre-Sheleko and Dangila abattoirs were estimated to be $18911.6. © 2009 Blackwell Verlag GmbH.

Retrospective comparison of thromboelastography results to postmortem evidence of thrombosis in critically ill dogs: 39 cases (2005-2010).

PubMed

Thawley, Vincent J; Sánchez, Melissa D; Drobatz, Kenneth J; King, Lesley G

2016-05-01

To determine whether there is an association between thromboelastography (TEG) data and necropsy evidence of thrombosis in a cohort of critically ill dogs. Retrospective study (2005-2010). University teaching hospital. Thirty-nine client-owned critically ill dogs for which TEG was performed within 7 days of complete necropsy. None. Thrombi were found in 26 (67%) dogs. Spayed females (n = 20) were significantly more likely to have thrombosis (P = 0.0127). No significant association was found between presence of thrombosis and any TEG parameter, the calculated coagulation index, results of coagulation testing, type of vascular access, or clinical diagnosis. D-dimers were significantly higher in dogs with thrombosis (P = 0.0207) and a weak positive correlation was found between D-dimer value and number of sites of thrombosis (ρ = 0.18, P = 0.0045). Dogs with WBC > 16 × 10(3) /μL were more likely to have thrombosis compared to others (odds ratio 5.56, 95% confidence interval 1.2-25.7, P = 0.025). This study found no association between any TEG parameter and the presence of thrombosis on postmortem examination. © Veterinary Emergency and Critical Care Society 2016.

Lung aeration on post-mortem magnetic resonance imaging is a useful marker of live birth versus stillbirth.

PubMed

Barber, Joy L; Sebire, Neil J; Chitty, Lyn S; Taylor, Andrew M; Arthurs, Owen J

2015-05-01

Aim of this study was to investigate whether lung assessment on post-mortem magnetic resonance imaging (PMMR) can reliably differentiate between live birth and stillbirth. We retrospectively assessed PMMR imaging features of a group of late foetal terminations following fetocide and stillbirths (without witnessed breathing) and early infant deaths (breathed spontaneously before death). PMMR images were reviewed for evidence of lung aeration and other features, blinded to the clinical and autopsy data. Nineteen infant deaths (mean age 3.0 ± 6.5 post-natal weeks) and 23 foetal terminations or stillbirths (mean age 32.6 ± 10.2-week gestation) were compared. Subjective appearances of lung aeration on PMMR were the best indicator of live birth, with a sensitivity of 89.5% (95% confidence interval 68.6, 97.1%) and specificity of 95.6% (79.0, 99.2%) and positive and negative predictive values of 94.4% and 91.7%, respectively. Lung aeration on PMMR appears to have high overall accuracy for confirmation of live birth versus intrauterine foetal death but now requires validating in a larger cohort of perinatal deaths.

Prevalence and distribution of Baylisascaris procyonis in urban raccoons (Procyon lotor) in Winnipeg, Manitoba.

PubMed

Sexsmith, Jennifer L; Whiting, Terry L; Green, Chris; Orvis, Sheldon; Berezanski, Dean J; Thompson, Amy B

2009-08-01

The prevalence of Baylisascaris procyonis was estimated in the urban raccoon population of Winnipeg through the fecal flotation of raccoon feces collected at active latrines and through gross postmortem and fecal flotation of samples collected from nuisance raccoons. Fecal flotation of latrine-collected feces was positive in 33 of 89 samples and, of 52 latrines identified, 26 were positive on 1 or more occasions. Trapped individual raccoons subjected to postmortem examination were positive in 57 of 114 animals captured. Comparing a single fecal flotation to the gold standard of finding adult worms in the small intestine had a sensitivity of 78.9% and specificity of 92.9%. This study suggests that carriage of Baylisascaris procyonis is widespread in raccoons in the Winnipeg urban ecosystem. Raccoon latrines in Winnipeg should be treated as infectious sites and efforts should be made to limit access of pets and people at risk to those sites.

[Post-mortem examination prior to cremation--an instrument to verify the quality of medical post-mortems and uncover non-natural deaths?].

PubMed

Germerott, Tanja; Todt, Melanie; Bode-Jänisch, Stefanie; Albrecht, Knut; Breitmeier, Dirk

2012-01-01

The external post-mortem examination, its deficient quality and possible causes have been the subject of numerous political and professional discussions. The external post-mortem examination is the basis for the decision whether further criminal investigations are required to clarify the cause of death. It is thus an essential instrument to ensure legal certainty. Before cremation, a second external post-mortem examination is performed by a public medical officer to make sure that errors of the first post-mortem are corrected. In the present study, cases were retrospectively analyzed in which a forensic autopsy had been ordered on the basis of the results of the post-mortem examination performed before cremation. The entries on the death certificate regarding the manner and cause of death were compared with the autopsy results. Between 1998 and 2007, 387 autopsies were ordered after external examination before cremation. In 55 cases (14.2%), the autopsy revealed a non-natural death, although a natural death had been attested on the death certificate. In descending order, a wrong manner of death was attested by clinicians, general practitioners and emergency physicians. With regard to the place where the first external post-mortem had been performed the lowest error rate was seen in nursing homes. Concerning the cause of death, discrepancies between the first post-mortem and autopsy were found in 59.4% of the cases. In this respect, general practitioners and clinicians were ranking first, whereas in nursing homes the cause of death was wrongly assessed in over 70% of cases. At present, the medical post-mortem does not meet the required quality standards, especially with regard to legal certainty. Determination of the cause of death on the basis of the external post-mortem examination is a challenging task even for the experienced medical examiner. As to the categorization of the manner of death it has to be stated that non-natural deaths are often not recognized or that the possibility to certify a death as unclear is not sufficiently used. As a result, it seems important to demand intensive, qualified, additional training in external post-mortem examinations for physicians.

Strengthen forensic entomology in court--the need for data exploration and the validation of a generalised additive mixed model.

PubMed

Baqué, Michèle; Amendt, Jens

2013-01-01

Developmental data of juvenile blow flies (Diptera: Calliphoridae) are typically used to calculate the age of immature stages found on or around a corpse and thus to estimate a minimum post-mortem interval (PMI(min)). However, many of those data sets don't take into account that immature blow flies grow in a non-linear fashion. Linear models do not supply a sufficient reliability on age estimates and may even lead to an erroneous determination of the PMI(min). According to the Daubert standard and the need for improvements in forensic science, new statistic tools like smoothing methods and mixed models allow the modelling of non-linear relationships and expand the field of statistical analyses. The present study introduces into the background and application of these statistical techniques by analysing a model which describes the development of the forensically important blow fly Calliphora vicina at different temperatures. The comparison of three statistical methods (linear regression, generalised additive modelling and generalised additive mixed modelling) clearly demonstrates that only the latter provided regression parameters that reflect the data adequately. We focus explicitly on both the exploration of the data--to assure their quality and to show the importance of checking it carefully prior to conducting the statistical tests--and the validation of the resulting models. Hence, we present a common method for evaluating and testing forensic entomological data sets by using for the first time generalised additive mixed models.

Bayesian networks for evaluation of evidence from forensic entomology.

PubMed

Andersson, M Gunnar; Sundström, Anders; Lindström, Anders

2013-09-01

In the aftermath of a CBRN incident, there is an urgent need to reconstruct events in order to bring the perpetrators to court and to take preventive actions for the future. The challenge is to discriminate, based on available information, between alternative scenarios. Forensic interpretation is used to evaluate to what extent results from the forensic investigation favor the prosecutors' or the defendants' arguments, using the framework of Bayesian hypothesis testing. Recently, several new scientific disciplines have been used in a forensic context. In the AniBioThreat project, the framework was applied to veterinary forensic pathology, tracing of pathogenic microorganisms, and forensic entomology. Forensic entomology is an important tool for estimating the postmortem interval in, for example, homicide investigations as a complement to more traditional methods. In this article we demonstrate the applicability of the Bayesian framework for evaluating entomological evidence in a forensic investigation through the analysis of a hypothetical scenario involving suspect movement of carcasses from a clandestine laboratory. Probabilities of different findings under the alternative hypotheses were estimated using a combination of statistical analysis of data, expert knowledge, and simulation, and entomological findings are used to update the beliefs about the prosecutors' and defendants' hypotheses and to calculate the value of evidence. The Bayesian framework proved useful for evaluating complex hypotheses using findings from several insect species, accounting for uncertainty about development rate, temperature, and precolonization. The applicability of the forensic statistic approach to evaluating forensic results from a CBRN incident is discussed.

The comparative performance of PMI estimation in skeletal remains by three methods (C-14, luminol test and OHI): analysis of 20 cases.

PubMed

Cappella, Annalisa; Gibelli, Daniele; Muccino, Enrico; Scarpulla, Valentina; Cerutti, Elisa; Caruso, Valentina; Sguazza, Emanuela; Mazzarelli, Debora; Cattaneo, Cristina

2015-01-27

When estimating post-mortem interval (PMI) in forensic anthropology, the only method able to give an unambiguous result is the analysis of C-14, although the procedure is expensive. Other methods, such as luminol tests and histological analysis, can be performed as preliminary investigations and may allow the operators to gain a preliminary indication concerning PMI, but they lack scientific verification, although luminol testing has been somewhat more accredited in the past few years. Such methods in fact may provide some help as they are inexpensive and can give a fast response, especially in the phase of preliminary investigations. In this study, 20 court cases of human skeletonized remains were dated by the C-14 method. For two cases, results were chronologically set after the 1950s; for one case, the analysis was not possible technically. The remaining 17 cases showed an archaeological or historical collocation. The same bone samples were also screened with histological examination and with the luminol test. Results showed that only four cases gave a positivity to luminol and a high Oxford Histology Index (OHI) score at the same time: among these, two cases were dated as recent by the radiocarbon analysis. Thus, only two false-positive results were given by the combination of these methods and no false negatives. Thus, the combination of two qualitative methods (luminol test and microscopic analysis) may represent a promising solution to cases where many fragments need to be quickly tested.

Genetic correlation of longevity with growth, post-mortem, docility and some morphological traits in the Pirenaica beef cattle breed.

PubMed

Varona, L; Moreno, C; Altarriba, J

2012-06-01

Survival or longevity is an economically relevant trait in cattle. However, it is not currently included in cattle selection criteria because of the delayed recording of phenotypic data and the high computational demand of survival techniques under proportional hazard models. The identification of longevity-correlated traits that can be early registered in lifetime would therefore be very useful for beef cattle selection processes. The aim of this study was to estimate the genetic correlation of survival (SURV) with: growth - birth weight (BW), weight at 120 days (W120), weight at 210 days (W210); carcass - cold carcass weight (CCW), conformation (CON), fatness (FAT) and meat colour (COL); teat morphology - teat thickness (TT), teat length (TL) and udder depth (UD); leg morphology - forward (FL) and backward legs (BL); milk production (MILK) and docility (DOC). In the statistical analysis, SURV was measured in discrete-time intervals and modelled via a sequential threshold model. A series of independent bivariate Bayesian analyses between cow survival and each recorded trait were carried out. The posterior mean estimates (and posterior standard deviation) for the heritability of SURV was 0.05 (0.01); and for the relevant genetic correlations with SURV were 0.07 (0.04), 0.12 (0.05), 0.10 (0.05), 0.15 (0.05), -0.18 (0.06), 0.33 (0.06) and 0.27 (0.15) for BW, W120, W210, CCW, CON, FAT and COL, respectively.

Stability of 26 Sedative Hypnotics in Six Toxicological Matrices at Different Storage Conditions.

PubMed

Mata, Dani C

2016-10-01

Forensic laboratories are challenged with backlogs that produce turnaround times that vary from days to months. Therefore, drug stability is important for interpretation in both antemortem (blood and urine) and postmortem (blood, brain, liver, stomach contents) cases. In this study, 23 benzodiazepines (2-hydroxyethylflurazepam, 7-aminoclonazepam, 7-aminoflunitrazepam, α-hydroxyalprazolam, α-hydroxytriazolam, alprazolam, bromazepam, chlordiazepoxide, clonazepam, demoxepam, desalkylflurazepam, diazepam, estazolam, flunitrazepam, flurazepam, lorazepam, midazolam, nitrazepam, nordiazepam, oxazepam, phenazepam, temazepam and triazolam) and three sedative hypnotics (zaleplon, zopiclone and zolpidem) were spiked into the six matrices at two different concentrations for each drug. The samples were stored in either a refrigerator (4°C) or freezer (-20°C) and analyzed in triplicate at various time intervals over an 8-month period using an SWGTOX validated method. The concentrations decreased over time regardless of the initial spiked concentration, and the storage conditions had little effect on the decrease of most drugs. Conversion from drug to metabolite was difficult to determine since all 26 drugs were present in each sample. Zopiclone and phenazepam were the least stable drugs; zopiclone was the only drug that completely disappeared in any matrix (both antemortem and postmortem blood). Urine was the most stable matrix with only phenazepam, 7-aminoclonazepam, 7-aminoflunitrazepam, 2-hydroxyethylflurazepam, and zopiclone decreasing >20% over the 8 months in either storage condition. Postmortem blood, the least stable matrix, had only two drugs, zolpidem and bromazepam, decreasing <20% in the 8-month time period. Further experiments on stability of these drugs should be undertaken to remove the freeze-thaw cycle effect and more thoroughly examining drug-metabolite conversion. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Pulmonary and cardiac pathology in sudden unexpected death in epilepsy (SUDEP).

PubMed

Nascimento, Fábio A; Tseng, Zian H; Palmiere, Cristian; Maleszewski, Joseph J; Shiomi, Takayuki; McCrillis, Aileen; Devinsky, Orrin

2017-08-01

To review studies on structural pulmonary and cardiac changes in SUDEP cases as well as studies showing pulmonary or cardiac structural changes in living epilepsy patients. We conducted electronic literature searches using the PubMed database for articles published in English, regardless of publication year, that included data on cardiac and/or pulmonary structural abnormalities in SUDEP cases or in living epilepsy patients during the postictal period. Fourteen postmortem studies reported pulmonary findings in SUDEP cases. Two focused mainly on assessing lung weights in SUDEP cases versus controls; no group difference was found. The other 12 reported descriptive autopsy findings. Among all SUDEP cases with available descriptive postmortem pulmonary examination, 72% had pulmonary changes, most often pulmonary edema/congestion, and, less frequently, intraalveolar hemorrhage. Eleven studies reported on cardiac pathology in SUDEP. Cardiac abnormalities were found in approximately one-fourth of cases. The most common findings were myocyte hypertrophy and myocardial fibrosis of various degrees. Among living epilepsy patients, postictal pulmonary pathology was the most commonly reported pulmonary abnormality and the most common postictal cardiac abnormality was transient left ventricular dysfunction - Takotsubo or neurogenic stunned myocardium. Cardiac and pulmonary pathological abnormalities are frequent among SUDEP cases, most commonly pulmonary edema/congestion and focal interstitial myocardial fibrosis. Most findings are not quantified, with subjective elements and undefined interobserver reliability, and lack of controls such as matched epilepsy patients who died from other causes. Further, studies have not systematically evaluated potential confounding factors, including postmortem interval to autopsy, paramedic resuscitation and IV fluids administration, underlying heart/lung disease, and risk factors for cardiac or pulmonary disease. Prospective studies with controls are needed to define the heart and lung changes in SUDEP and understand their potential relationship to mechanisms of death in SUDEP. Copyright © 2017 Elsevier Inc. All rights reserved.

Maintenance of arytenoid abduction following carbon dioxide laser debridement of the articular cartilage and joint capsule of the cricoarytenoid joint combined with prosthetic laryngoplasty in horses: an in vivo and in vitro study.

PubMed

Hawkins, J F; Couetil, L; Miller, M A

2014-02-01

The objective was to evaluate CO2 laser debridement of the cricoarytenoid joint (CAJ) combined with prosthetic laryngoplasty to prevent post-operative loss of arytenoid abduction in seven horses. Horses were assigned to either laser debridement of the left CAJ and laryngoplasty (laser treated, n=5) or control laryngoplasty (sham, n=2), and were evaluated with endoscopic examinations and measurement of right to left angle quotients (RLQ) to assess maintenance of arytenoid abduction. The animals were euthanased at intervals after surgery and larynges were harvested for post-mortem testing, including determination of translaryngeal flow, pressure, impedance and RLQ. Measurements were obtained under increasing vacuum-generated negative pressure with laryngoplasty sutures intact and with the knot/crimp of the laryngoplasty sutures removed. Following post-mortem testing the cricoarytenoid joints were examined histologically. Post-operative endoscopic examinations revealed no significant differences between RLQ measurements calculated for day 1 following surgery to the termination date of the study for the seven horses. Post-mortem RLQ at airflows of 10 and 60 L/s was significantly higher in sham than in laser treated horses both before and after knot/crimp removal. Translaryngeal impedance at 10 and 60 L/s was not statistically different between groups. Histopathology revealed necrosis and loss of articular cartilage in the laser treated horses. The lymphoid cell infiltration subsided but joint capsule and periarticular fibrosis increased over the course of the study. Post-operative loss of arytenoid abduction after laryngoplasty can be minimized with CO2 laser debridement of the CAJ joint. Copyright © 2013 Elsevier Ltd. All rights reserved.

When a death apparently associated to sexual assault is instead a natural death due to idiopathic hypereosinophilic syndrome: The importance of gamma-hydroxybutyric acid analysis in vitreous humor.

PubMed

Busardò, Francesco Paolo; Portelli, Francesca; Montana, Angelo; Rotolo, Maria Concetta; Pichini, Simona; Maresi, Emiliano

2017-05-01

We here report a case involving a 21-year-old female, found dead in a central square of a city in the south of Italy. Initial evidences and circumstances were suggestive of a death associated with a sexual assault. Two peripheral blood and two vitreous humor samples were collected for the purpose of gamma-hydroxybutyric acid (GHB) testing from the dead body at two different post-mortem intervals (PMIs): approximately 2 (t 0 ) and 36 (t 1 ) hours. The obtained results showed that, between t 0 and t 1, there was an increase of GHB concentrations in peripheral blood and vitreous humor of 66.3% and 8.1%, respectively. This case was the first evidence of GHB post mortem production in a dead body and not in vitro, showing that vitreous humor is less affected than peripheral blood in GHB post-mortem production. The value detected at t 1 in peripheral blood (53.4µg/mL) exceeded the proposed cut-off and if interpreted alone would have led to erroneous conclusions. This was not the case of vitreous humor GHB, whose post-mortem increase was minimal and it allowed to exclude a GHB exposure. Only after a broad forensic investigation including a complete autopsy, serological, histological, toxicological and haematology analyses, a diagnosis of idiopathic hypereosinophilic syndrome, a myeloproliferative disorder characterized by persistent eosinophilia associated with damage to multiple organs, was made and the cause of death was due to a pulmonary eosinophilic vasculitis responsible for an acute respiratory failure. Copyright © 2017 Elsevier B.V. All rights reserved.

Pork Quality Traits According to Postmortem pH and Temperature in Berkshire

PubMed Central

Kim, Tae Wan; Kim, Chul Wook; Yang, Mi Ra; No, Gun Ryoung; Kim, Il-Suk

2016-01-01

This study was performed to investigate the role of pH and temperature postmortem, and to demonstrate the importance of these factors in determining meat quality. Postmortem pH45min (pH at 45 min postmortem or initial pH) via analysis of Pearson’s correlation showed high positive correlation with pH change pHc24 (pH change from pH45min to pH24h postmortem). However, postmortem pH after 24 h (pH24h or ultimate pH) had a high negative correlation with pH change, pHc24, CIE L*, and protein content. Initial temperature postmortem (T1h ) was positively associated with a change in temperature from 45 min to 24 h postmortem (Tc24) and cooking loss, but negatively correlated with water holding capacity. Temperature at 24 h postmortem (T24h) was negatively associated with Tc24. Collectively, these results indicate that higher initial pH was associated with higher pHc24, T1h, and Tc24. However, higher initial pH was associated with a reduction in carcass weight, backfat thickness, CIE a* and b*, water holding capacity, collagen and fat content, drip loss, and cooking loss as well as decreased shear force. In contrast, CIE a* and b*, drip loss, cooking loss, and shear force in higher ultimate pH was showed by a similar pattern to higher initial pH, whereas pHc24, carcass weight, backfat thickness, water holding capacity, fat content, moisture content, protein content, T1h, T24h, and Tc24 were exhibited by completely differential patterns (p<0.05). Therefore, we suggest that initial pH, ultimate pH, and temperatures postmortem are important factors in determining the meat quality of pork. PMID:27499661

Successive bacterial colonisation of pork and its implications for forensic investigations.

PubMed

Handke, Jessica; Procopio, Noemi; Buckley, Michael; van der Meer, Dieudonne; Williams, Graham; Carr, Martin; Williams, Anna

2017-12-01

Bacteria are considered one of the major driving forces of the mammalian decomposition process and have only recently been recognised as forensic tools. At this point, little is known about their potential use as 'post-mortem clocks'. This study aimed to establish the proof of concept for using bacterial identification as post-mortem interval (PMI) indicators, using a multi-omics approach. Pieces of pork were placed in the University's outdoor facility and surface swabs were taken at regular intervals up to 60 days. Terminal restriction fragment length polymorphism (T-RFLP) of the 16S rDNA was used to identify bacterial taxa. It succeeded in detecting two out of three key contributors involved in decomposition and represents the first study to reveal Vibrionaceae as abundant on decomposing pork. However, a high fraction of present bacterial taxa could not be identified by T-RFLP. Proteomic analyses were also performed at selected time points, and they partially succeeded in the identification of precise strains, subspecies and species of bacteria that colonized the body after different PMIs. T-RFLP is incapable of reliably and fully identifying bacterial taxa, whereas proteomics could help in the identification of specific strains of bacteria. Nevertheless, microbial identification by next generation sequencing might be used as PMI clock in future investigations and in conjunction with information provided by forensic entomologists. To the best of our knowledge, this work represents the first attempt to find a cheaper and easily accessible, culture-independent alternative to high-throughput techniques to establish a 'microbial clock', in combination with proteomic strategies to address this issue. Copyright © 2017 Elsevier B.V. All rights reserved.

Adverse events, toxicity and post-mortem data on duloxetine: case reports and literature survey.

PubMed

Vey, Eric L; Kovelman, Inna

2010-05-01

Duloxetine, a dual acting norepinephrine serotonin reuptake inhibitor, is a relatively new pharmacologic agent utilized in the treatment of depression, as well as diabetic neuropathic pain, fibromyalgia, and female stress urinary incontinence. This expanding scope of usage will inevitably lead to its eventual appearance during routine post-mortem toxicologic assays. Currently there is a paucity of post-mortem toxicologic data concerning duloxetine. The current report provides six additional case reports of post-mortem duloxetine levels, along with a review of duloxetine's pharmacokinetics, and the toxicologic manifestations which have been reported in the literature. The post-mortem levels reported, including the highest level recorded to date, are integrated with previously published reports to generate a foundation for a nascent guide to the interpretation of post-mortem duloxetine levels that could be encountered during routine post-mortem toxicologic analyses, and establish a basis upon which the establishment of toxic and lethal thresholds for this compound can be further elucidated with greater clarity. Copyright (c) 2010 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Long-term bowhead whale abundance data collected near Point Barrow Alaska (1978-2011) and postmortem examination data (1974-2012)

NASA Astrophysics Data System (ADS)

George, J.; Suydam, R.

2012-12-01

Primarily in response to concerns about the sustainability of the subsistence bowhead whale harvest along the Alaskan coast, population surveys were initiated by NOAA in 1978, and were conducted by the North Slope Borough from 1981 to present. The surveys of migrating bowhead whales were made from pressure ridges on the landfast sea ice margin in the vicinity of Point Barrow, Alaska. Surveys were conducted 24 hr/day from about 15 April and 1 June depending on weather and ice conditions. Specific observation data include: (for each whale sighting) date, time, location, whale group size, species, migration speed and direction, (every 2 hrs) ice floe speed and direction (surrogate for current data), weather, pressure ridge height, bird observations and other data. Full-time acoustic surveillance during the survey has been conducted from 1984 to present. A statistically significant positive trend (3.5% year; 95% CI=2.2-4.8%) in bowhead whale population size is evident over this time period. The more recent abundance estimate was 12,631 (CV 0.2442) whales for year 2004. Over a more extensive time period, postmortem examinations of bowhead whales landed by Inupiat Eskimos have been made at Barrow and other whale hunting villages. We have detailed whale examination data from 1974-present with sporadic harvest data dating to the 1800s. The older records lack the detail of current examinations. These "harvest data" are connected with estimates of Yankee commercial whaling takes from 1848 to 1915 compiled by other researchers. Together they provide a continuous record of anthropogenic takes of bowhead whales for more than 150 years. These datasets have been essential in estimating sustainable harvest levels by the International Whaling Commission Scientific Committee, NOAA and the Alaska Eskimo Whaling Commission. The records are also used for modeling environmental effects on bowheads, oil and gas leasing decisions, and many other scientific projects and policy matters. The postmortem examinations provide an important means to monitor the general health condition of bowhead whales regarding long-term trends in body condition, parasite loads, contaminate loads and many other health parameters.

Radioactive isotope analyses of skeletal materials in forensic science: a review of uses and potential uses.

PubMed

Cook, Gordon T; MacKenzie, Angus B

2014-07-01

A review of information that can be provided from measurements made on natural and anthropogenic radionuclide activities in human skeletal remains has been undertaken to establish what reliable information of forensic anthropological use can be obtained regarding years of birth and death (and hence post-mortem interval (PMI)). Of the anthropogenic radionuclides that have entered the environment, radiocarbon ((14)C) can currently be used to generate the most useful and reliable information. Measurements on single bones can indicate whether or not the person died during the nuclear era, while recent research suggests that measurements on trabecular bone may, depending on the chronological age of the remains, provide estimates of year of death and hence PMI. Additionally, (14)C measurements made on different components of single teeth or on teeth formed at different times can provide estimates of year of birth to within 1-2 years of the true year. Of the other anthropogenic radionuclides, (90)Sr shows some promise but there are problems of (1) variations in activities between individuals, (2) relatively large analytical uncertainties and (3) diagenetic contamination. With respect to natural series radionuclides, it is concluded that there is no convincing evidence that (210)Pb dating can be used in a rigorous, quantitative fashion to establish a PMI. Similarly, for daughter/parent pairs such as (210)Po/(210)Pb (from the (238)U decay series) and (228)Th/(228)Ra (from the (232)Th decay series), the combination of analytical uncertainty and uncertainty in activity ratios at the point of death inevitably results in major uncertainty in any estimate of PMI. However, observation of the disequilibrium between these two daughter/parent pairs could potentially be used in a qualitative way to support other forensic evidence.

Hematocrit Measurement with R2* and Quantitative Susceptibility Mapping in Postmortem Brain.

PubMed

Walsh, A J; Sun, H; Emery, D J; Wilman, A H

2018-05-24

Noninvasive venous oxygenation quantification with MR imaging will improve the neurophysiologic investigation and the understanding of the pathophysiology in neurologic diseases. Available MR imaging methods are limited by sensitivity to flow and often require assumptions of the hematocrit level. In situ postmortem imaging enables evaluation of methods in a fully deoxygenated environment without flow artifacts, allowing direct calculation of hematocrit. This study compares 2 venous oxygenation quantification methods in in situ postmortem subjects. Transverse relaxation (R2*) mapping and quantitative susceptibility mapping were performed on a whole-body 4.7T MR imaging system. Intravenous measurements in major draining intracranial veins were compared between the 2 methods in 3 postmortem subjects. The quantitative susceptibility mapping technique was also applied in 10 healthy control subjects and compared with reference venous oxygenation values. In 2 early postmortem subjects, R2* mapping and quantitative susceptibility mapping measurements within intracranial veins had a significant and strong correlation ( R 2 = 0.805, P = .004 and R 2 = 0.836, P = .02). Higher R2* and susceptibility values were consistently demonstrated within gravitationally dependent venous segments during the early postmortem period. Hematocrit ranged from 0.102 to 0.580 in postmortem subjects, with R2* and susceptibility as large as 291 seconds -1 and 1.75 ppm, respectively. Measurements of R2* and quantitative susceptibility mapping within large intracranial draining veins have a high correlation in early postmortem subjects. This study supports the use of quantitative susceptibility mapping for evaluation of in vivo venous oxygenation and postmortem hematocrit concentrations. © 2018 by American Journal of Neuroradiology.

Application of contrast media in post-mortem imaging (CT and MRI).

PubMed

Grabherr, Silke; Grimm, Jochen; Baumann, Pia; Mangin, Patrice

2015-09-01

The application of contrast media in post-mortem radiology differs from clinical approaches in living patients. Post-mortem changes in the vascular system and the absence of blood flow lead to specific problems that have to be considered for the performance of post-mortem angiography. In addition, interpreting the images is challenging due to technique-related and post-mortem artefacts that have to be known and that are specific for each applied technique. Although the idea of injecting contrast media is old, classic methods are not simply transferable to modern radiological techniques in forensic medicine, as they are mostly dedicated to single-organ studies or applicable only shortly after death. With the introduction of modern imaging techniques, such as post-mortem computed tomography (PMCT) and post-mortem magnetic resonance (PMMR), to forensic death investigations, intensive research started to explore their advantages and limitations compared to conventional autopsy. PMCT has already become a routine investigation in several centres, and different techniques have been developed to better visualise the vascular system and organ parenchyma in PMCT. In contrast, the use of PMMR is still limited due to practical issues, and research is now starting in the field of PMMR angiography. This article gives an overview of the problems in post-mortem contrast media application, the various classic and modern techniques, and the issues to consider by using different media.

Interpretation of postmortem change in cadavers in Spain.

PubMed

Prieto, José L; Magaña, Concepción; Ubelaker, Douglas H

2004-09-01

Estimating time since death is especially difficult in the examination of poorly preserved cadavers and depends on the experience of the examiner and comparison with previously documented cases showing similar characteristics. The present study reports on information obtained over the past ten years through the work of the Laboratorio de Antropología y Odontología Forense (LAF) of the Instituto Anatómico Forense de Madrid, Spain, in particular evaluating how the type of fracture influences postmortem change. From the original 225 forensic cases examined between 1992 and 2002 in the LAF, a sample of 29 cases were selected from various regions of the Spanish mainland. A data collection protocol was established to reflect factors which the existing specialized literature, documenting the relation existing in the sample analyzed between time since death and the extent of postmortem change, which in the environments examined are distributed into the following phases: Phase 1 (putrefaction): one week to one month on the surface and two months in water. Phase 2 (initial skeletonization): two months on the surface and five to six months in water. Phase 3 (advanced skeltonization): six months to 1.5 years on the surface and 2.5 years buried. Phase 4 (complete skeletonization): about one year on the surface and three years buried. This paper also provide useful information on the impact of carrion insect activity, location, climate, seasonality, and predator.

Immune involvement in the pathogenesis of schizophrenia: a meta-analysis on postmortem brain studies

PubMed Central

van Kesteren, C F M G; Gremmels, H; de Witte, L D; Hol, E M; Van Gool, A R; Falkai, P G; Kahn, R S; Sommer, I E C

2017-01-01

Although the precise pathogenesis of schizophrenia is unknown, genetic, biomarker and imaging studies suggest involvement of the immune system. In this study, we performed a systematic review and meta-analysis of studies investigating factors related to the immune system in postmortem brains of schizophrenia patients and healthy controls. Forty-one studies were included, reporting on 783 patients and 762 controls. We divided these studies into those investigating histological alterations of cellular composition and those assessing molecular parameters; meta-analyses were performed on both categories. Our pooled estimate on cellular level showed a significant increase in the density of microglia (P=0.0028) in the brains of schizophrenia patients compared with controls, albeit with substantial heterogeneity between studies. Meta-regression on brain regions demonstrated this increase was most consistently observed in the temporal cortex. Densities of macroglia (astrocytes and oligodendrocytes) did not differ significantly between schizophrenia patients and healthy controls. The results of postmortem histology are paralleled on the molecular level, where we observed an overall increase in expression of proinflammatory genes on transcript and protein level (P=0.0052) in patients, while anti-inflammatory gene expression levels were not different between schizophrenia and controls. The results of this meta-analysis strengthen the hypothesis that components of the immune system are involved in the pathogenesis of schizophrenia. PMID:28350400

[Conceiling the cadaver in masonry and cement].

PubMed

Madea, Burkhard; Cremer, Ulrich; Schiwy-Bochat, Karl Heinz

2003-01-01

Encasing with concrete and/or bricks are relatively rare forms of hiding or disposing of a body; criminologically, cases of this kind are often treated as "matters involving a missing person" at first. The article describes the circumstances and findings of 2 cases in which bodies were encased with concrete. Under the aspects of reconstruction it is of importance that bodies may be preserved quite well in concrete, which allows not only identification of the victim but also determination of the cause of death even after a prolonged post-mortem interval, the more so as occasionally tools used for committing the offense are also encased together with the body.

A novel approach to determine post mortem interval using neutron radiography.

PubMed

Bilheux, Hassina Z; Cekanova, Maria; Vass, Arpad A; Nichols, Trent L; Bilheux, Jean C; Donnell, Robert L; Finochiarro, Vincenzo

2015-06-01

One of the most difficult challenges in forensic research is to objectively determine the post-mortem interval (PMI). The accuracy of PMI is critical for determining the timeline of events surrounding a death. Most PMI techniques rely on gross morphological changes of cadavers that are highly sensitive to taphonomic factors. Recent studies have demonstrated that even exhumed individuals exposed to the same environmental conditions with similar PMIs can present different stages of decomposition. After death, tissue undergoes sequential changes consisting of organic and inorganic phase variations, as well as a gradual reduction of tissue water content. Hydrogen (H) is the primary contributor to neutron radiography (NR) contrast in biological specimens because (1) it is the most abundant element in biological tissues and (2) its nucleus scatters thermal and cold neutrons more strongly than any other atomic nucleus. These contrast differences can be advantageous in a forensic context to determine small changes in hydrogen concentrations. Neutron radiography of decaying canine tissues was performed to evaluate the PMI by measuring the changes in H content. In this study, dog cadavers were used as a model for human cadavers. Canine tissues and cadavers were exposed to controlled (laboratory settings, at the University of Tennessee, College of Veterinary Medicine) and uncontrolled (University of Tennessee Anthropology Research Facility) environmental conditions, respectively. Neutron radiographs were supplemented with photographs and histology data to assess the decompositional stages of cadavers. Results demonstrated that the increase in neutron transmission likely corresponded to a decrease in hydrogen content in the tissue, which was correlated with the decay time of the tissue. Tissues depleted in hydrogen were brighter in the neutron transmission radiographs of skeletal muscles, lung, and bone, under controlled conditions. Over a period of 10 days, changes in neutron transmission through lung and muscle were found to be higher than bone by 8.3%, 7.0%, and 2.0%, respectively. Results measured during uncontrolled conditions were more difficult to assess and further studies are necessary. In conclusion, neutron radiography may be used to detect changes in hydrogen abundance that can be correlated with the post-mortem interval. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Combining Architecture-Centric Engineering with the Team Software Process

DTIC Science & Technology

2010-12-01

colleagues from Quarksoft and CIMAT have re- cently reported on their experiences in “Introducing Software Architecture Development Methods into a TSP...Postmortem Lessons, new goals, new requirements, new risk , etc. Business and technical goals Estimates, plans, process, commitment Work products...architecture to mitigate the risks unco- vered by the ATAM. At the end of the iteration, version 1.0 of the architec- ture is available. Implement a second

Post-mortem clinical pharmacology

PubMed Central

Ferner, R E

2008-01-01

Clinical pharmacology assumes that deductions can be made about the concentrations of drugs from a knowledge of the pharmacokinetic parameters in an individual; and that the effects are related to the measured concentration. Post-mortem changes render the assumptions of clinical pharmacology largely invalid, and make the interpretation of concentrations measured in post-mortem samples difficult or impossible. Qualitative tests can show the presence of substances that were not present in life, and can fail to detect substances that led to death. Quantitative analysis is subject to error in itself, and because post-mortem concentrations vary in largely unpredictable ways with the site and time of sampling, as a result of the phenomenon of post-mortem redistribution. Consequently, compilations of ‘lethal concentrations’ are misleading. There is a lack of adequate studies of the true relationship between fatal events and the concentrations that can be measured subsequently, but without such studies, clinical pharmacologists and others should be wary of interpreting post-mortem measurements. PMID:18637886

The difficult task of assessing perimortem and postmortem fractures on the skeleton: a blind text on 210 fractures of known origin.

PubMed

Cappella, Annalisa; Amadasi, Alberto; Castoldi, Elisa; Mazzarelli, Debora; Gaudio, Daniel; Cattaneo, Cristina

2014-11-01

The distinction between perimortem and postmortem fractures is an important challenge for forensic anthropology. Such a crucial task is presently based on macro-morphological criteria widely accepted in the scientific community. However, several limits affect these parameters which have not yet been investigated thoroughly. This study aims at highlighting the pitfalls and errors in evaluating perimortem or postmortem fractures. Two trained forensic anthropologists were asked to classify 210 fractures of known origin in four skeletons (three victims of blunt force trauma and one natural death) as perimortem, postmortem, or dubious, twice in 6 months in order to assess intraobserver error also. Results show large errors, ranging from 14.8 to 37% for perimortem fractures and from 5.5 to 14.8% for postmortem ones; more than 80% of errors concerned trabecular bone. This supports the need for more objective and reliable criteria for a correct assessment of peri- and postmortem bone fractures. © 2014 American Academy of Forensic Sciences.

Co-registration of In-Vivo Human MRI Brain Images to Postmortem Histological Microscopic Images

PubMed Central

Singh, M.; Rajagopalan, A.; Kim, T.-S.; Hwang, D.; Chui, H.; Zhang, X.-L.; Lee, A.-Y.; Zarow, C.

2009-01-01

Certain features such as small vascular lesions seen in human MRI are detected reliably only in postmortem histological samples by microscopic imaging. Co-registration of these microscopically detected features to their corresponding locations in the in-vivo images would be of great benefit to understanding the MRI signatures of specific diseases. Using non-linear Polynomial transformation, we report a method to co-register in-vivo MRIs to microscopic images of histological samples drawn off the postmortem brain. The approach utilizes digital photographs of postmortem slices as an intermediate reference to co-register the MRIs to microscopy. The overall procedure is challenging due to gross structural deformations in the postmortem brain during extraction and subsequent distortions in the histological preparations. Hemispheres of the brain were co-registered separately to mitigate these effects. Approaches relying on matching single-slices, multiple-slices and entire volumes in conjunction with different similarity measures suggested that using four slices at a time in combination with two sequential measures, Pearson correlation coefficient followed by mutual information, produced the best MRI-postmortem co-registration according to a voxel mismatch count. The accuracy of the overall registration was evaluated by measuring the 3D Euclidean distance between the locations of microscopically identified lesions on postmortem slices and their MRI-postmortem co-registered locations. The results show a mean 3D displacement of 5.1 ± 2.0 mm between the in-vivo MRI and microscopically determined locations for 21 vascular lesions in 11 subjects. PMID:19169415

DNA-Based Identification of Forensically Important Blow Flies (Diptera: Calliphoridae) From India.

PubMed

Bharti, Meenakshi; Singh, Baneshwar

2017-09-01

Correct species identification is the first and the most important criteria in entomological evidence-based postmortem interval (PMI) estimation. Although morphological keys are available for species identification of adult blow flies, keys for immature stages are either lacking or are incomplete. In this study, cytochrome oxidase subunit 1 (COI) reference data were developed from nine species (belonging to three subfamilies, namely, Calliphorinae, Luciliinae, and Chrysomyinae) of blow flies from India. Seven of the nine species included in this study were found suitable for DNA-based identification using COI gene, because they showed nonoverlapping intra- (0.0-0.3%) and inter-(1.96-18.14%) specific diversity, and formed well-supported monophyletic clade in phylogenetic analysis. The remaining two species (i.e., Chrysomya megacephala (Fabricius) and Chrysomya chani Kurahashi) cannot be distinguished reliably using our database because they had a very low interspecific diversity (0.11%), and Ch. megacephala was paraphyletic with respect to Ch. chani in the phylogenetic analysis. We conclude that the COI gene is a useful marker for DNA-based identification of blow flies from India. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Using the Developmental Gene Bicoid to Identify Species of Forensically Important Blowflies (Diptera: Calliphoridae)

PubMed Central

Park, Seong Hwan; Park, Chung Hyun; Zhang, Yong; Piao, Huguo; Chung, Ukhee; Kim, Seong Yoon; Ko, Kwang Soo; Yi, Cheong-Ho; Jo, Tae-Ho; Hwang, Juck-Joon

2013-01-01

Identifying species of insects used to estimate postmortem interval (PMI) is a major subject in forensic entomology. Because forensic insect specimens are morphologically uniform and are obtained at various developmental stages, DNA markers are greatly needed. To develop new autosomal DNA markers to identify species, partial genomic sequences of the bicoid (bcd) genes, containing the homeobox and its flanking sequences, from 12 blowfly species (Aldrichina grahami, Calliphora vicina, Calliphora lata, Triceratopyga calliphoroides, Chrysomya megacephala, Chrysomya pinguis, Phormia regina, Lucilia ampullacea, Lucilia caesar, Lucilia illustris, Hemipyrellia ligurriens and Lucilia sericata; Calliphoridae: Diptera) were determined and analyzed. This study first sequenced the ten blowfly species other than C. vicina and L. sericata. Based on the bcd sequences of these 12 blowfly species, a phylogenetic tree was constructed that discriminates the subfamilies of Calliphoridae (Luciliinae, Chrysomyinae, and Calliphorinae) and most blowfly species. Even partial genomic sequences of about 500 bp can distinguish most blowfly species. The short intron 2 and coding sequences downstream of the bcd homeobox in exon 3 could be utilized to develop DNA markers for forensic applications. These gene sequences are important in the evolution of insect developmental biology and are potentially useful for identifying insect species in forensic science. PMID:23586044

Lucilia silvarum Meigen, 1826 (Diptera: Calliphoridae)--a new species of interest for forensic entomology in Europe.

PubMed

Fremdt, Heike; Szpila, Krzysztof; Huijbregts, Johannes; Lindström, Anders; Zehner, Richard; Amendt, Jens

2012-10-10

In Europe, the blowfly genus Lucilia is represented in Forensic Entomology mainly by the species L. ampullacea, L. caesar, L. illustris and L. sericata. In the US, Lucilia silvarum is rarely recorded as a carrion breeding species but usually as a more or less exclusive parasite of frogs and toads. We present three forensic cases from different European countries reporting, for the first time, L. silvarum on human bodies that were found close to lakes, wetlands, or riversides. To use this species for post-mortem interval estimations, thermal development data is needed. The first step is accurate identification by morphological and molecular means. Therefore, we analysed a 611 bp part of the mitochondrial COI region for 23 specimens of L. silvarum from 9 different geographical regions, all of which give the same haplotype. Differences within the haplotype varied by up to 0.2%. Comparison between the haplotype found and those published on GenBank showed up to 1.2% variance. Moreover, we present an updated key for the morphological identification of the third larval instars of European Lucilia spp. of forensic importance, adding not only L. silvarum, but also L. cuprina which was recorded in Europe for the first time about 20 years ago. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Chemotaxonomic Profile and Intraspecific Variation in the Blow Fly of Forensic Interest Chrysomya megacephala (Diptera: Calliphoridae).

PubMed

Paula, Michele C; Antonialli-Junior, William F; Mendonça, Angélica; Michelutti, Kamylla B; Eulalio, Aylson D M M; Cardoso, Claudia A L; de Lima, Thiago; Von Zuben, Cláudio J

2017-01-01

Necrophagous insects such as blow flies (Diptera: Calliphoridae) are considered crucial in forensic entomology. Identification at species level and determination of larval stage are the basis for estimation of postmortem interval (PMI). Insect evidence can also be used in the determination of crime scenes, since body displacement is common. The aim of this study was to determine the chemotaxonomic profile and intraspecific variability of the forensically important blow fly Chrysomya megacephala (F. 1794). Adults were collected in the municipalities of Dourados-MS (Brazil) and Rio Claro-SP (Brazil), and then transferred to the laboratory for oviposition and development of the immature stages. Chemical analysis of cuticular compounds was performed by gas chromatography. Cuticular chemical profiles varied significantly between the two populations, as well as between developmental stages, supporting the use of these compounds as a complementary tool to help identify the species and its stages, along with geographical variability. This could greatly accelerate forensic investigations, eliminating the need to allow the fly larvae to develop until adult stage in order to confirm the species identity and sample origin. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Are the evidences of forensic entomology preserved in ethanol suitable for SEM studies?

PubMed

López-Esclapez, Raquel; García, María-Dolores; Arnaldos, María-Isabel; Presa, Juan José; Ubero-Pascal, Nicolás

2014-07-01

In forensic practice, the use of arthropod evidences to estimate the postmortem interval is a very good approach when the elapsed time from death is long, but it requires the correct identification of the specimens. This is a crucial step, not always easy to achieve, in particular when dealing with immature specimens. In this case, scanning electronic microscopy (SEM) can be useful, but the techniques used to preserve specimens in forensic practice are usually different from those used to prepare specimens for SEM studies. To determine whether forensic evidences preserving techniques are also compatible with SEM analysis, we have compared specimens of all the immature stages of Calliphora vicina Robineau-Desvoidy, 1830 (Diptera, Calliphoridae) preserved in 70% ethanol, with others prepared with aldehydic fixative techniques that are more appropriate for SEM studies. At the same time, two drying techniques have also been compared with both fixative techniques, the critical point drying and air-drying following with hexamethyldisilizane treatment (HMDS). Our results indicate that there are not basis against recommending the use of ethanol to preserve forensic entomological evidences and that both drying methods appear to offer good results for second and third instar larvae, although HMDS behaves better with eggs and pupae. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparing Species Composition of Passive Trapping of Adult Flies with Larval Collections from the Body during Scene-Based Medicolegal Death Investigations

PubMed Central

Sanford, Michelle R.

2017-01-01

Collection of insects at the scene is one of the most important aspects of forensic entomology and proper collection is one of the biggest challenges for any investigator. Adult flies are highly mobile and ubiquitous at scenes, yet their link to the body and the time of colonization (TOC) and post-mortem interval (PMI) estimates is not well established. Collection of adults is widely recommended for casework but has yet to be rigorously evaluated during medicolegal death investigations for its value to the investigation. In this study, sticky card traps and immature collections were compared for 22 cases investigated by the Harris County Institute of Forensic Sciences, Houston, TX, USA. Cases included all manner of death classifications and a range of decomposition stages from indoor and outdoor scenes. Overall, the two methods successfully collected at least one species in common only 65% of the time, with at least one species unique to one of the methods 95% of the time. These results suggest that rearing of immature specimens collected from the body should be emphasized during training to ensure specimens directly associated with the colonization of the body can be identified using adult stages if necessary. PMID:28338605

Genomic regions underlying susceptibility to bovine tuberculosis in Holstein-Friesian cattle.

PubMed

Raphaka, Kethusegile; Matika, Oswald; Sánchez-Molano, Enrique; Mrode, Raphael; Coffey, Mike Peter; Riggio, Valentina; Glass, Elizabeth Janet; Woolliams, John Arthur; Bishop, Stephen Christopher; Banos, Georgios

2017-03-23

The significant social and economic loss as a result of bovine tuberculosis (bTB) presents a continuous challenge to cattle industries in the UK and worldwide. However, host genetic variation in cattle susceptibility to bTB provides an opportunity to select for resistant animals and further understand the genetic mechanisms underlying disease dynamics. The present study identified genomic regions associated with susceptibility to bTB using genome-wide association (GWA), regional heritability mapping (RHM) and chromosome association approaches. Phenotypes comprised de-regressed estimated breeding values of 804 Holstein-Friesian sires and pertained to three bTB indicator traits: i) positive reactors to the skin test with positive post-mortem examination results (phenotype 1); ii) positive reactors to the skin test regardless of post-mortem examination results (phenotype 2) and iii) as in (ii) plus non-reactors and inconclusive reactors to the skin tests with positive post-mortem examination results (phenotype 3). Genotypes based on the 50 K SNP DNA array were available and a total of 34,874 SNPs remained per animal after quality control. The estimated polygenic heritability for susceptibility to bTB was 0.26, 0.37 and 0.34 for phenotypes 1, 2 and 3, respectively. GWA analysis identified a putative SNP on Bos taurus autosomes (BTA) 2 associated with phenotype 1, and another on BTA 23 associated with phenotype 2. Genomic regions encompassing these SNPs were found to harbour potentially relevant annotated genes. RHM confirmed the effect of these genomic regions and identified new regions on BTA 18 for phenotype 1 and BTA 3 for phenotypes 2 and 3. Heritabilities of the genomic regions ranged between 0.05 and 0.08 across the three phenotypes. Chromosome association analysis indicated a major role of BTA 23 on susceptibility to bTB. Genomic regions and candidate genes identified in the present study provide an opportunity to further understand pathways critical to cattle susceptibility to bTB and enhance genetic improvement programmes aiming at controlling and eradicating the disease.

Portraying the Dead.

ERIC Educational Resources Information Center

Ruby, Jay

1989-01-01

Explores custom of post-mortem photography. Describes practice of post-mortem photography in 19th century America and traces changes in post-mortem photography in the 20th century. Discusses value of photographs in mourning process and suggests more thorough examination of the place of death-related photographs in grief management. (Author/NB)

[Post-mortem microbiology analysis].

PubMed

Fernández-Rodríguez, Amparo; Alberola, Juan; Cohen, Marta Cecilia

2013-12-01

Post-mortem microbiology is useful in both clinical and forensic autopsies, and allows a suspected infection to be confirmed. Indeed, it is routinely applied to donor studies in the clinical setting, as well as in sudden and unexpected death in the forensic field. Implementation of specific sampling techniques in autopsy can minimize the possibility of contamination, making interpretation of the results easier. Specific interpretation criteria for post-mortem cultures, the use of molecular diagnosis, and its fusion with molecular biology and histopathology have led to post-mortem microbiology playing a major role in autopsy. Multidisciplinary work involving microbiologists, pathologists, and forensic physicians will help to improve the achievements of post-mortem microbiology, prevent infectious diseases, and contribute to a healthier population. Crown Copyright © 2012. Published by Elsevier Espana. All rights reserved.

The Relationship Between the Changes in Local Stiffness of Chicken Myofibril and the Tenderness of Muscle During Postmortem Aging

NASA Astrophysics Data System (ADS)

Iwasaki, T.; Hasegawa, Y.; Yamamoto, K.; Nakamura, K.

We have investigated that the relationship between the stiffness of myofibrils and the tenderness of muscle during postmortem aging. The stiffness (elasticity) of A and I bands as well as Z-line of chicken myofibrils during postmortem aging were measured by atomic force microscope. The stiffness of all regions increased till 12 hr of postmortem, then it decreased to 96 hr. This tendency was the same as the changes of shear force value of whole muscle during postmortem aging. The elasticity of the Z-line of chicken myofibrils treated with calcium ions in the presence of protease inhibitor decreased with treating time. This indicates that the nonenzymatic structural changes of myofibrils is one of the causes of meat tenderization.

The impact of antemortem computed tomographic scanning on postmortem examination rate and frequency of missed diagnosis: A retrospective analysis of postmortem examination data.

PubMed

Liisanantti, Janne Henrik; Ala-Kokko, Tero Ilmari

2015-12-01

The present study was conducted to explore the impact of computed tomographic (CT) scanning on the diagnostic discrepancy rate. This single-center, retrospective study reviewed postmortem examination results, clinical diagnoses, and radiologic imaging data for patients admitted to the intensive care unit (ICU) in 2008 to 2013. The Goldman criteria were used to classify diagnostic discrepancies. The data of 577 patients who died during their ICU stay were retrieved. The postmortem examination rate was 42.9% (n=248). Significant diagnostic discrepancies (Goldman I and II) were recorded in 24 cases (9.7%). The postmortem examination rate decreased significantly from the first half (n=143; 51.1%) to the second half (n=105; 35.4%) of the study period (P<.0001). Among those with postmortem examinations, the use of antemortem body CT scans increased significantly from the first half (n=59; 41.3%) to the second half (n=64; 51.0%; P=.002) of the study period. The significant diagnostic discrepancy rate did not change with time (8.4% vs 11.4%, respectively; P=.424). The postmortem examination rate has decreased, whereas antemortem CT scans has increased. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparing interval estimates for small sample ordinal CFA models

PubMed Central

Natesan, Prathiba

2015-01-01

Robust maximum likelihood (RML) and asymptotically generalized least squares (AGLS) methods have been recommended for fitting ordinal structural equation models. Studies show that some of these methods underestimate standard errors. However, these studies have not investigated the coverage and bias of interval estimates. An estimate with a reasonable standard error could still be severely biased. This can only be known by systematically investigating the interval estimates. The present study compares Bayesian, RML, and AGLS interval estimates of factor correlations in ordinal confirmatory factor analysis models (CFA) for small sample data. Six sample sizes, 3 factor correlations, and 2 factor score distributions (multivariate normal and multivariate mildly skewed) were studied. Two Bayesian prior specifications, informative and relatively less informative were studied. Undercoverage of confidence intervals and underestimation of standard errors was common in non-Bayesian methods. Underestimated standard errors may lead to inflated Type-I error rates. Non-Bayesian intervals were more positive biased than negatively biased, that is, most intervals that did not contain the true value were greater than the true value. Some non-Bayesian methods had non-converging and inadmissible solutions for small samples and non-normal data. Bayesian empirical standard error estimates for informative and relatively less informative priors were closer to the average standard errors of the estimates. The coverage of Bayesian credibility intervals was closer to what was expected with overcoverage in a few cases. Although some Bayesian credibility intervals were wider, they reflected the nature of statistical uncertainty that comes with the data (e.g., small sample). Bayesian point estimates were also more accurate than non-Bayesian estimates. The results illustrate the importance of analyzing coverage and bias of interval estimates, and how ignoring interval estimates can be misleading. Therefore, editors and policymakers should continue to emphasize the inclusion of interval estimates in research. PMID:26579002

Comparing interval estimates for small sample ordinal CFA models.

PubMed

Natesan, Prathiba

2015-01-01

Robust maximum likelihood (RML) and asymptotically generalized least squares (AGLS) methods have been recommended for fitting ordinal structural equation models. Studies show that some of these methods underestimate standard errors. However, these studies have not investigated the coverage and bias of interval estimates. An estimate with a reasonable standard error could still be severely biased. This can only be known by systematically investigating the interval estimates. The present study compares Bayesian, RML, and AGLS interval estimates of factor correlations in ordinal confirmatory factor analysis models (CFA) for small sample data. Six sample sizes, 3 factor correlations, and 2 factor score distributions (multivariate normal and multivariate mildly skewed) were studied. Two Bayesian prior specifications, informative and relatively less informative were studied. Undercoverage of confidence intervals and underestimation of standard errors was common in non-Bayesian methods. Underestimated standard errors may lead to inflated Type-I error rates. Non-Bayesian intervals were more positive biased than negatively biased, that is, most intervals that did not contain the true value were greater than the true value. Some non-Bayesian methods had non-converging and inadmissible solutions for small samples and non-normal data. Bayesian empirical standard error estimates for informative and relatively less informative priors were closer to the average standard errors of the estimates. The coverage of Bayesian credibility intervals was closer to what was expected with overcoverage in a few cases. Although some Bayesian credibility intervals were wider, they reflected the nature of statistical uncertainty that comes with the data (e.g., small sample). Bayesian point estimates were also more accurate than non-Bayesian estimates. The results illustrate the importance of analyzing coverage and bias of interval estimates, and how ignoring interval estimates can be misleading. Therefore, editors and policymakers should continue to emphasize the inclusion of interval estimates in research.

A novel approach to determine post mortem interval using neutron radiography

DOE PAGES

Bilheux, Hassina Z.; Cekanova, Maria; Vass, Arpad Alexander; ...

2015-03-06

In this study, neutron radiography (NR) is used non-destructively to measure changes in hydrogen (H) content in decaying tissues as a mean to estimate post-mortem invertal (PMI). After death, tissue undergoes sequential changes consisting of organic and inorganic phase variations, as well as a gradual reduction of tissue water content. H is the primary contributor to NR contrast in biological specimens because (1) it is the most abundant element in biological tissues and (2) its nucleus scatter thermal and cold neutrons more strongly than any other atomic nucleus. These contrast differences can be advantageous in a forensic context to determinemore » small changes in hydrogen concentrations. Dog cadavers were used as a model for human cadavers. Canine tissues and cadavers were exposed to controlled (laboratory settings) and uncontrolled (University of Tennessee Anthropology Research Facility) environmental conditions during putefraction, respectively. Neutron radiographs were supplemented with photographs and histology data to assess the decomposition stage of cadavers. Results demonstrated that the increase in neutron transmission likely corresponded to a decrease in hydrogen content in the tissue, which was correlated with the time of decay of the tissue. Tissues depleted in hydrogen are brighter in the neutron transmission radiographs of skeletal muscles, lung, and bone, under controlled conditions. Over a period of 10 days, changes in neutron transmission through lung and muscle were found to be higher than bone by 8.3%, 7.0 %, and 2.0 %, respectively. Estimation of the PMI was calculated from a natural logarithmic fitting of the NR data. Under controlled conditions, estimation of the PMI was 70% and 63.9 % accurate for bone and lung tissues, while being 1.4% accurate for muscle tissue. All results underestimated the true PMI. In conclusion, neutron radiography can be used for detection of hydrogen changes in decaying tissues to estimate PMI.« less

Hydrocarbon profiles throughout adult Calliphoridae aging: A promising tool for forensic entomology.

PubMed

Pechal, Jennifer L; Moore, Hannah; Drijfhout, Falko; Benbow, M Eric

2014-12-01

Blow flies (Diptera: Calliphoridae) are typically the first insects to arrive at human remains and carrion. Predictable succession patterns and known larval development of necrophagous insects on vertebrate remains can assist a forensic entomologist with estimates of a minimum post-mortem interval (PMImin) range. However, adult blow flies are infrequently used to estimate the PMImin, but rather are used for a confirmation of larval species identification. Cuticular hydrocarbons have demonstrated potential for estimating adult blow fly age, as hydrocarbons are present throughout blow fly development, from egg to adult, and are stable structures. The goal of this study was to identify hydrocarbon profiles associated with the adults of a North American native blow fly species, Cochliomyia macellaria (Fabricius) and a North American invasive species, Chrysomya rufifacies (Macquart). Flies were reared at a constant temperature (25°C), a photoperiod of 14:10 (L:D) (h), and were provided water, sugar and powdered milk ad libitum. Ten adult females from each species were collected at day 1, 5, 10, 20, and 30 post-emergence. Hydrocarbon compounds were extracted and then identified using gas chromatography-mass spectrometry (GC-MS) analysis. A total of 37 and 35 compounds were detected from C. macellaria and Ch. rufifacies, respectively. There were 24 and 23 n-alkene and methyl-branched alkane hydrocarbons from C. macellaria and Ch. rufifacies, respectively (10 compounds were shared between species), used for statistical analysis. Non-metric multidimensional scaling analysis and permutational multivariate analysis of variance were used to analyze the hydrocarbon profiles with significant differences (P<0.001) detected among post-emergence age cohorts for each species, and unique hydrocarbon profiles detected as each adult blow fly species aged. This work provides empirical data that serve as a foundation for future research into improving PMImin estimates made by forensic practitioners and potentially increase the use of adult insects during death investigations. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

A novel approach to determine post mortem interval using neutron radiography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bilheux, Hassina Z.; Cekanova, Maria; Vass, Arpad Alexander

In this study, neutron radiography (NR) is used non-destructively to measure changes in hydrogen (H) content in decaying tissues as a mean to estimate post-mortem invertal (PMI). After death, tissue undergoes sequential changes consisting of organic and inorganic phase variations, as well as a gradual reduction of tissue water content. H is the primary contributor to NR contrast in biological specimens because (1) it is the most abundant element in biological tissues and (2) its nucleus scatter thermal and cold neutrons more strongly than any other atomic nucleus. These contrast differences can be advantageous in a forensic context to determinemore » small changes in hydrogen concentrations. Dog cadavers were used as a model for human cadavers. Canine tissues and cadavers were exposed to controlled (laboratory settings) and uncontrolled (University of Tennessee Anthropology Research Facility) environmental conditions during putefraction, respectively. Neutron radiographs were supplemented with photographs and histology data to assess the decomposition stage of cadavers. Results demonstrated that the increase in neutron transmission likely corresponded to a decrease in hydrogen content in the tissue, which was correlated with the time of decay of the tissue. Tissues depleted in hydrogen are brighter in the neutron transmission radiographs of skeletal muscles, lung, and bone, under controlled conditions. Over a period of 10 days, changes in neutron transmission through lung and muscle were found to be higher than bone by 8.3%, 7.0 %, and 2.0 %, respectively. Estimation of the PMI was calculated from a natural logarithmic fitting of the NR data. Under controlled conditions, estimation of the PMI was 70% and 63.9 % accurate for bone and lung tissues, while being 1.4% accurate for muscle tissue. All results underestimated the true PMI. In conclusion, neutron radiography can be used for detection of hydrogen changes in decaying tissues to estimate PMI.« less

Distribution of kerosene components in rats following dermal exposure.

PubMed

Tsujino, Y; Hieda, Y; Kimura, K; Eto, H; Yakabe, T; Takayama, K; Dekio, S

2002-08-01

The systemic distribution of kerosene components in blood and tissues was analysed in rats following dermal exposure. Four types of trimethylbenzenes (TMBs) and aliphatic hydrocarbons (AHCs) with carbon numbers 9-16 (C(9)-C(16)) were analysed as major kerosene components by capillary gas chromatography/mass spectrometry (GC/MS). The kerosene components were detected in blood and all tissues after a small piece of cotton soaked with kerosene was applied to the abdominal skin. The amounts of TMBs detected were higher than those of AHCs. Greater increases in TMB levels were found in adipose tissue in an exposure duration-dependent manner. The amounts of TMBs detected were only at trace levels following post-mortem dermal exposure to kerosene. These findings suggest that kerosene components were absorbed percutaneously and distributed to various organs via the blood circulation. Post-mortem or ante-mortem exposure to kerosene could be distinguished when the exposure duration was relatively long. Adipose tissue would seem to be the most useful for estimating the degree of kerosene exposure.

Seasonal necrophagous insect community assembly during vertebrate carrion decomposition.

PubMed

Benbow, M E; Lewis, A J; Tomberlin, J K; Pechal, J L

2013-03-01

Necrophagous invertebrates have been documented to be a predominant driver of vertebrate carrion decomposition; however, very little is understood about the assembly of these communities both within and among seasons. The objective of this study was to evaluate the seasonal differences in insect taxa composition, richness, and diversity on carrion over decomposition with the intention that such data will be useful for refining error estimates in forensic entomology. Sus scrofa (L.) carcasses (n = 3-6, depending on season) were placed in a forested habitat near Xenia, OH, during spring, summer, autumn, and winter. Taxon richness varied substantially among seasons but was generally lower (1-2 taxa) during early decomposition and increased (3-8 taxa) through intermediate stages of decomposition. Autumn and winter showed the highest richness during late decomposition. Overall, taxon richness was higher during active decay for all seasons. While invertebrate community composition was generally consistent among seasons, the relative abundance of five taxa significantly differed across seasons, demonstrating different source communities for colonization depending on the time of year. There were significantly distinct necrophagous insect communities for each stage of decomposition, and between summer and autumn and summer and winter, but the communities were similar between autumn and winter. Calliphoridae represented significant indicator taxa for summer and autumn but replaced by Coleoptera during winter. Here we demonstrated substantial variability in necrophagous communities and assembly on carrion over decomposition and among seasons. Recognizing this variation has important consequences for forensic entomology and future efforts to provide error rates for estimates of the postmortem interval using arthropod succession data as evidence during criminal investigations.

Postmortem ventilation in cases of penetrating gunshot and stab wounds to the chest.

PubMed

Germerott, Tanja; Preiss, Ulrich S; Ross, Steffen G; Thali, Michael J; Flach, Patricia M

2013-11-01

We sought to determine the effect of postmortem ventilation in combination with a suction pump in cases showing penetrating trauma to the chest with haemo- and/or pneumothorax, for better evaluation of the lungs in postmortem computed tomography (PMCT). The study included 6 subjects (1 female, 5 male; age 32-67years) with a penetrating gunshot or stab wound to the chest and consecutive pneumo- and/or haemothorax. The pneumo- and haemothorax were evacuated by a suction pump, and postmortem ventilation was applied using a home care ventilator. PMCT images with and without postmortem ventilation were compared, as well as the autopsy results. In three cases haemo- and pneumothorax was clearly reduced. Postmortem ventilation led to distinct re-expansion of the lungs in two cases, and to re-expansion of single lung lobes in two cases with shotgun injuries. No visible effect was seen in the remaining two cases, because of extensive destruction of lung tissue and blood aspiration. In two cases the injuries sustained in the individual lung lobes were successfully located during postmortem ventilation. The bullet channel was apparent in one case; in another case, injury of the pericardium became visible by generating pneumopericardium. The present method is capable of improving evaluation of the postmortem lung in the presence of single stab or gunshot wounds and if there is no severe destruction of the respiratory system and aspiration. Forensic autopsy should still be considered as the gold standard, although in some cases the present method might be helpful, especially where no autopsy is required. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Effect of postmortem aging on marination performance of broiler breast pectoralis major categorized by color lightness

USDA-ARS?s Scientific Manuscript database

The objective was to evaluate the effect of postmortem aging on marinade uptake and retention by early-deboned chicken breast fillets with different color lightness. Effects of marination on product yield and muscle shear force were also determined. Early deboned (2 h postmortem) broiler butterflies...

42 CFR 35.16 - Autopsies and other post-mortem operations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 1 2014-10-01 2014-10-01 false Autopsies and other post-mortem operations. 35.16 Section 35.16 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICAL CARE AND EXAMINATIONS HOSPITAL AND STATION MANAGEMENT General § 35.16 Autopsies and other post-mortem...

42 CFR 35.16 - Autopsies and other post-mortem operations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 1 2011-10-01 2011-10-01 false Autopsies and other post-mortem operations. 35.16 Section 35.16 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICAL CARE AND EXAMINATIONS HOSPITAL AND STATION MANAGEMENT General § 35.16 Autopsies and other post-mortem...

42 CFR 35.16 - Autopsies and other post-mortem operations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 1 2013-10-01 2013-10-01 false Autopsies and other post-mortem operations. 35.16 Section 35.16 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICAL CARE AND EXAMINATIONS HOSPITAL AND STATION MANAGEMENT General § 35.16 Autopsies and other post-mortem...

42 CFR 35.16 - Autopsies and other post-mortem operations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Autopsies and other post-mortem operations. 35.16 Section 35.16 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICAL CARE AND EXAMINATIONS HOSPITAL AND STATION MANAGEMENT General § 35.16 Autopsies and other post-mortem...

42 CFR 35.16 - Autopsies and other post-mortem operations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 1 2012-10-01 2012-10-01 false Autopsies and other post-mortem operations. 35.16 Section 35.16 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICAL CARE AND EXAMINATIONS HOSPITAL AND STATION MANAGEMENT General § 35.16 Autopsies and other post-mortem...

9 CFR 355.41 - Antemortem and postmortem inspection for mules.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Animal Food, Mule Meat By-Product § 355.41 Antemortem and postmortem inspection for mules. (a)(1) An... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Antemortem and postmortem inspection for mules. 355.41 Section 355.41 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...

Virtopsy: postmortem imaging of laryngeal foreign bodies.

PubMed

Oesterhelweg, Lars; Bolliger, Stephan A; Thali, Michael J; Ross, Steffen

2009-05-01

Death from corpora aliena in the larynx is a well-known entity in forensic pathology. The correct diagnosis of this cause of death is difficult without an autopsy, and misdiagnoses by external examination alone are common. To determine the postmortem usefulness of modern imaging techniques in the diagnosis of foreign bodies in the larynx, multislice computed tomography, magnetic resonance imaging, and postmortem full-body computed tomography-angiography were performed. Three decedents with a suspected foreign body in the larynx underwent the 3 different imaging techniques before medicolegal autopsy. Multislice computed tomography has a high diagnostic value in the noninvasive localization of a foreign body and abnormalities in the larynx. The differentiation between neoplasm or soft foreign bodies (eg, food) is possible, but difficult, by unenhanced multislice computed tomography. By magnetic resonance imaging, the discrimination of the soft tissue structures and soft foreign bodies is much easier. In addition to the postmortem multislice computed tomography, the combination with postmortem angiography will increase the diagnostic value. Postmortem, cross-sectional imaging methods are highly valuable procedures for the noninvasive detection of corpora aliena in the larynx.

[External post-mortem examination].

PubMed

Hartwig, S

2016-09-01

The external post-mortem examination in Germany is a non-delegable medical duty for determination of death, identity of the deceased, cause of death, manner of death, time of death and notifiable infectious diseases. Within the framework of rescue service missions the physician is limited to ascertaining that death has occurred. The determination of death must be reliable and is automatically followed by a complete external post-mortem examination of the body, if necessary by another physician. The certain signs of death are livor mortis, rigor mortis and putrefaction. Reliable features for the occurrence of death are injuries which are not compatible with life and brain death. The external post-mortem examination is the basis for the decision on whether further criminal investigations are necessary. The external post-mortem examination and the accompanying death certification must always be meticulously carried out.

Sarcomere length influences postmortem proteolysis of excised bovine semitendinosus muscle.

PubMed

Weaver, A D; Bowker, B C; Gerrard, D E

2008-08-01

The interaction between sarcomere length and postmortem proteolysis as related to meat tenderness is not clear. The extent of thick and thin filament overlap alters actomyosin binding and may alter substrate availability during aging-induced tenderization. The objective of this study was to determine the influence of sarcomere length on proteolytic degradation in beef. Strips from bovine semitendinosus were either stretched 40% and restrained or allowed to shorten unrestrained in an ice bath. After rigor completion, 0.6-cm cross sections were fabricated and were randomly assigned to 2, 4, 7, or 10 d of aging treatments. Myofibrils were isolated for sarcomere length determination. Samples were collected and frozen for shear force analysis, and muscle proteins were extracted for SDS-PAGE and Western blotting analyses to determine troponin T (TnT) proteolysis. Sarcomere length was greater (P < 0.01) in stretched muscle samples compared with shortened samples (2.57 vs. 1.43 microm, respectively). Correspondingly, shear force values were greater (P < 0.05) in shortened samples than stretched samples. Western blots revealed the presence of 3 major intact TnT bands that diminished with time postmortem and 4 bands (TnT degradation products) that accumulated during postmortem storage. Quantification of intact TnT showed increased (P < 0.05) proteolysis at 4 and 7 d postmortem in samples with long sarcomeres. By 10 d, only traces of the greatest molecular weight intact TnT band were evident in both shortened and stretched samples, suggesting this TnT band may be more susceptible to proteolysis than other intact TnT bands. Degradation products of TnT appeared earlier postmortem in samples with long sarcomeres. The 30-kDa TnT fragment appeared after 7 d of postmortem storage in samples with long sarcomeres but not until 10 d in muscle containing short sarcomeres. Collectively, these data show that postmortem TnT proteolysis is sarcomere length-dependent and suggest that thick and thin filament overlap may influence the postmortem aging process in beef.

Digital image processing of vascular angiograms

NASA Technical Reports Server (NTRS)

Selzer, R. H.; Beckenbach, E. S.; Blankenhorn, D. H.; Crawford, D. W.; Brooks, S. H.

1975-01-01

The paper discusses the estimation of the degree of atherosclerosis in the human femoral artery through the use of a digital image processing system for vascular angiograms. The film digitizer uses an electronic image dissector camera to scan the angiogram and convert the recorded optical density information into a numerical format. Another processing step involves locating the vessel edges from the digital image. The computer has been programmed to estimate vessel abnormality through a series of measurements, some derived primarily from the vessel edge information and others from optical density variations within the lumen shadow. These measurements are combined into an atherosclerosis index, which is found in a post-mortem study to correlate well with both visual and chemical estimates of atherosclerotic disease.

Survival and re-operation rates after neurosurgical procedures in Scotland: implications for targeted surveillance of sub-clinical variant Creutzfeldt-Jakob disease.

PubMed

Bird, Sheila M; Merrall, Elizabeth L C; Ward, Hester J T; Will, Robert G

2009-01-01

To assess the feasibility of post-mortem surveillance for subclinical variant Creutzfeldt-Jakob disease (vCJD) at least 5 years after neurosurgical procedures. Using Scottish record linkage, we estimated 5-year survival and re-operation rates after 4 neurosurgical procedures performed during 1993-2001 and identified as high or medium risk for transmitting vCJD: [B] drainage of extra- or subdural haematoma, [E] primary or revisional decompression operations and [H] creation of other ventricular shunts were classified as high risk; [C] operations on cerebral aneurysm (clipping) were classified as medium risk. Fatality rate at 1 year depended strongly on procedure, weakly or not at all on sex and era, and increased with age. Procedure rates differed by sex. The rate of subsequent neurosurgical operations was highest for procedure [H] (sole: 21%; multiple: 28%). Each year, the UK has a new cohort of some 5,000 5-year survivors after a high- or medium-risk neurosurgical procedure, whose subsequent annual mortality is at least 3%. Even if half the surviving 5-year survivors of neurosurgery since 1996 gave consent-in-life for vCJD-informative testing at post-mortem, there would be too few relevant post-mortems in 2008-2010 (around 1,600) for 'nil detections' to exclude a 1 in 1,000 subclinical vCJD rate. Autopsy surveillance beyond 2010, or among 5-year survivors of non-neurosurgical at-risk operations, would be needed. (c) 2009 S. Karger AG, Basel.

Causes and manners of death among users of heroin, methadone, amphetamine, and cannabis in relation to postmortem chemical tests for illegal drugs.

PubMed

Eksborg, Staffan; Rajs, Jovan

2008-01-01

A 12-year medicolegal investigation of deceased illegal drug users (ILDU) in Stockholm, Sweden, classified on the basis of postmortem chemical tests, showed noticeable variations in causes and manners of death as well as in the distribution of suicide methods. This study offers objective information about connection between the postmortem findings of illegal drugs and the causes and manners of death of their users. However, further studies, comparing prevalence of drug use in general population and at the postmortem tests, are needed for more detailed elucidation of this connection.

Running a postmortem service--a business case and clinical experience.

PubMed

Cohen, Marta C; Whitby, Elspeth; Fink, Michelle A; Collett, Jacquelene M; Offiah, Amaka C

2015-04-01

The purpose of the postmortem examination is to offer answers to explain the cause and manner of death. In the case of perinatal, infant and paediatric postmortem examinations, the goal is to identify unsuspected associated features, to describe pathogenic mechanisms and new conditions, and to evaluate the clinical management and diagnosis. Additionally, the postmortem examination is useful to counsel families regarding the probability of recurrence in future pregnancies and to inform family planning. Worldwide the rate of paediatric autopsy examinations has significantly declined during the last few decades. Religious objections to postmortem dissection and organ retention scandals in the United Kingdom provided some of the impetus for a search for non-invasive alternatives to the traditional autopsy; however, until recently, imaging studies remained an adjunct to, rather than a replacement for, the traditional autopsy. In 2012, Sheffield Children's Hospital National Health Service Foundation Trust set up the service provision of minimally invasive fetal, perinatal and neonatal autopsy, while a postmortem imaging service has been running in Melbourne, Australia, since 2008. Here we summarise the essentials of a business case and practical British and Australian experiences in terms of the pathological and radiologic aspects of setting up a minimally invasive clinical service in the United Kingdom and of developing a clinical postmortem imaging service as a complementary tool to the traditional autopsy in Australia.

[The theory of postmortem rigidity: the history and an original concept].

PubMed

Kil'diushov, E M; Tumanov, É V; Sokolova, Z Iu

2012-01-01

The original theory of postmortem rigidity has been developed and substantiated based on the concept of postmortem muscular contracture. It is postulated that the unrestricted growth of Ca2+ concentration in myoplasm of contractile cells during the immediate postmortal period brings the actin-myosine complex to the force generation state without subsequent relaxation.

Postmortem aging and freezing and thawing storage enhance ability of early deboned chicken pectoralis major muscle to hold added salt water

USDA-ARS?s Scientific Manuscript database

The effects of postdeboning aging and frozen storage on water-holding capacity (WHC) of chicken breast pectoralis major muscle were investigated. Broiler breast muscle was removed from carcasses either early postmortem (2 h) or later postmortem (24 h). Treatments included: no postdeboning aging; 1-...

Distribution of \\0x03949-Tetrahydrocannabinol and 11-Nor-9-Carboxy-\\0x03949-Tetrahydrocannabinol acid in postmortem biological fluids and tissues from pilots fatally injured in aviation accidents.

DOT National Transportation Integrated Search

2013-12-01

Despite a long history of research on the pharmacology of 9-tetrahydrocannabinol (THC), the primary active cannabinoid in marijuana, little is known of its distribution in postmortem fluids and tissues. This study presents postmortem fluid and tiss...

[Postmortem CT examination in a case of alleged drowning--a case report].

PubMed

Woźniak, Krzysztof; Urbanik, Andrzej; Rzepecka-Woźniak, Ewa; Moskała, Artur; Kłys, Małgorzata

2009-01-01

The authors present an analysis of postmortem CT examination in a case of drowning in fresh water of a young male. Both the results of conventional forensic autopsy and radiologic examination have been compared. The analysis is illustrated by two-dimensional and three-dimensional reconstructions based on the DICOM files obtained during postmortem CT examination.

[DNA Extraction from Old Bones by AutoMate Express™ System].

PubMed

Li, B; Lü, Z

2017-08-01

To establish a method for extracting DNA from old bones by AutoMate Express™ system. Bones were grinded into powder by freeze-mill. After extraction by AutoMate Express™, DNA were amplified and genotyped by Identifiler®Plus and MinFiler™ kits. DNA were extracted from 10 old bone samples, which kept in different environments with the postmortem interval from 10 to 20 years, in 3 hours by AutoMate Express™ system. Complete STR typing results were obtained from 8 samples. AutoMate Express™ system can quickly and efficiently extract DNA from old bones, which can be applied in forensic practice. Copyright© by the Editorial Department of Journal of Forensic Medicine

Nocturnal Oviposition Behavior of Forensically Important Diptera in Central England.

PubMed

Barnes, Kate M; Grace, Karon A; Bulling, Mark T

2015-11-01

Timing of oviposition on a corpse is a key factor in entomologically based minimum postmortem interval (mPMI) calculations. However, there is considerable variation in nocturnal oviposition behavior of blow flies reported in the research literature. This study investigated nocturnal oviposition in central England for the first time, over 25 trials from 2011 to 2013. Liver-baited traps were placed in an urban location during control (diurnal), and nocturnal periods and environmental conditions were recorded during each 5-h trial. No nocturnal activity or oviposition was observed during the course of the study indicating that nocturnal oviposition is highly unlikely in central England. © 2015 American Academy of Forensic Sciences.

[Forensic entomology exemplified by a homicide. A combined stain and postmortem time analysis].

PubMed

Benecke, M; Seifert, B

1999-01-01

The combined analysis of both ant and blow fly evidence recovered from a corpse, and from the boot of a suspect, suggested that an assumed scenario in a high profile murder case was likely to be true. The ants (Lasius fuliginous) were used as classical crime scene stains that linked the suspect to the scene. Blow fly maggots (Calliphora spec.) helped to determine the post mortem interval (PMI) with the calculated PMI overlapping with the assumed time of the killing. In the trial, the results of the medico-legal analysis of the insects was understood to be crucial scientific evidence, and the suspect was sentenced to 8 years in prison.

Qualification of serological infectious disease assays for the screening of samples from deceased tissue donors.

PubMed

Kitchen, A D; Newham, J A

2011-05-01

Whilst some of the assays used for serological screening of post-mortem blood samples from deceased tissue donors in some countries have been specifically validated by the manufacturer for this purpose, a significant number of those currently in use globally have not. Although specificity has previously been considered a problem in the screening of such samples, we believe that ensuring sensitivity is more important. The aim of this study was to validate a broader range of assays for the screening of post-mortem blood samples from deceased tissue donors. Six microplate immunoassays currently in use within National Health Service Blood and Transplant (NHSBT) for the screening of blood, tissue and stem cell donations were included. Representative samples from confirmed positive donors were titrated in screen negative post-mortem samples in parallel with normal pooled negative serum to determine if there was any inhibition with the post-mortem samples. There were no significant differences seen (P < 0.005) between the dilution curves obtained for the positive samples diluted in post-mortem samples and normal pooled sera. Although small numbers of samples were studied, it can be surmised that the post-mortem blood samples from deceased tissue donors, collected according to United Kingdom guidelines, are a suitable substrate for the assays evaluated. No diminution of reactivity was seen when dilution with sera from deceased donors was compared to dilution using pooled serum from live donors. In the absence of genuine low titre positive post-mortem samples, the use of samples spiked with various levels of target material provides a means of qualifying serological screening assays used by NHSBT for the screening of post-mortem blood samples from deceased tissue donors.

Meat quality and rigor mortis development in broiler chickens with gas-induced anoxia and postmortem electrical stimulation.

PubMed

Sams, A R; Dzuik, C S

1999-10-01

This study was conducted to evaluate the combined rigor-accelerating effects of postmortem electrical stimulation (ES) and argon-induced anoxia (Ar) of broiler chickens. One hundred broilers were processed in the following treatments: untreated controls, ES, Ar, or Ar with ES (Ar + ES). Breast fillets were harvested at 1 h postmortem for all treatments or at 1 and 6 h postmortem for the control carcasses. Fillets were sampled for pH and ratio of inosine to adenosine (R-value) and were then individually quick frozen (IQF) or aged on ice (AOI) until 24 h postmortem. Color was measured in the AOI fillets at 24 h postmortem. All fillets were then cooked and evaluated for Allo-Kramer shear value. The Ar treatment accelerated the normal pH decline, whereas the ES and AR + ES treatments yielded even lower pH values at 1 h postmortem. The Ar + ES treatment had a greater R-value than the ES treatment, which was greater than either the Ar or 1-h controls, which, in turn, were not different from each other. The ES treatment had the lowest L* value, and ES, Ar, and Ar + ES produced significantly higher a* values than the 1-h controls. For the IQF fillets, the ES and Ar + ES treatments were not different in shear value but were lower than Ar, which was lower than the 1-h controls. The same was true for the AOI fillets except that the ES and the Ar treatments were not different. These results indicated that although ES and Ar had rigor-accelerating and tenderizing effects, ES seemed to be more effective than Ar; there was little enhancement when Ar was added to the ES treatment and fillets were deboned at 1 h postmortem.

Whole brain analysis of postmortem density changes of grey and white matter on computed tomography by statistical parametric mapping.

PubMed

Nishiyama, Yuichi; Kanayama, Hidekazu; Mori, Hiroshi; Tada, Keiji; Yamamoto, Yasushi; Katsube, Takashi; Takeshita, Haruo; Kawakami, Kazunori; Kitagaki, Hajime

2017-06-01

This study examined the usefulness of statistical parametric mapping (SPM) for investigating postmortem changes on brain computed tomography (CT). This retrospective study included 128 patients (23 - 100 years old) without cerebral abnormalities who underwent unenhanced brain CT before and after death. The antemortem CT (AMCT) scans and postmortem CT (PMCT) scans were spatially normalized using our original brain CT template, and postmortem changes of CT values (in Hounsfield units; HU) were analysed by the SPM technique. Compared with AMCT scans, 58.6 % and 98.4 % of PMCT scans showed loss of the cerebral sulci and an unclear grey matter (GM)-white matter (WM) interface, respectively. SPM analysis revealed a significant decrease in cortical GM density within 70 min after death on PMCT scans, suggesting cytotoxic brain oedema. Furthermore, there was a significant increase in the density of the WM, lenticular nucleus and thalamus more than 120 min after death. The SPM technique demonstrated typical postmortem changes on brain CT scans, and revealed that the unclear GM-WM interface on early PMCT scans is caused by a rapid decrease in cortical GM density combined with a delayed increase in WM density. SPM may be useful for assessment of whole brain postmortem changes. • The original brain CT template achieved successful normalization of brain morphology. • Postmortem changes in the brain were independent of sex. • Cortical GM density decreased rapidly after death. • WM and deep GM densities increased following cortical GM density change. • SPM could be useful for assessment of whole brain postmortem changes.

Differences in sampling techniques on total post-mortem tryptase.

PubMed

Tse, R; Garland, J; Kesha, K; Elstub, H; Cala, A D; Ahn, Y; Stables, S; Palmiere, C

2018-05-01

The measurement of mast cell tryptase is commonly used to support the diagnosis of anaphylaxis. In the post-mortem setting, the literature recommends sampling from peripheral blood sources (femoral blood) but does not specify the exact sampling technique. Sampling techniques vary between pathologists, and it is unclear whether different sampling techniques have any impact on post-mortem tryptase levels. The aim of this study is to compare the difference in femoral total post-mortem tryptase levels between two sampling techniques. A 6-month retrospective study comparing femoral total post-mortem tryptase levels between (1) aspirating femoral vessels with a needle and syringe prior to evisceration and (2) femoral vein cut down during evisceration. Twenty cases were identified, with three cases excluded from analysis. There was a statistically significant difference (paired t test, p < 0.05) between mean post-mortem tryptase by aspiration (10.87 ug/L) and by cut down (14.15 ug/L). The mean difference between the two methods was 3.28 ug/L (median, 1.4 ug/L; min, - 6.1 ug/L; max, 16.5 ug/L; 95% CI, 0.001-6.564 ug/L). Femoral total post-mortem tryptase is significantly different, albeit by a small amount, between the two sampling methods. The clinical significance of this finding and what factors may contribute to it are unclear. When requesting post-mortem tryptase, the pathologist should consider documenting the exact blood collection site and method used for collection. In addition, blood samples acquired by different techniques should not be mixed together and should be analyzed separately if possible.

Search for fungi-specific metabolites of four model drugs in postmortem blood as potential indicators of postmortem fungal metabolism.

PubMed

Martínez-Ramírez, Jorge A; Strien, Juliane; Walther, Grit; Peters, Frank T

2016-05-01

Fungi colonizing cadavers are capable of drug metabolism and may thus change the metabolite pattern or concentration of drugs in forensic postmortem samples. The purpose of this study was to check for the presence of such changes by searching fungi-specific metabolites of four model drugs (amitriptyline, metoprolol, mirtazapine, and zolpidem) in decomposed postmortem blood samples from 33 cases involving these drugs. After isolation and identification of fungal strains present in the samples, each isolate was incubated in Sabouraud medium at 25°C for up to 120h with each model drug. One part of the supernatants was directly analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), another after liquid-liquid extraction with chlorobutane and concentration. From 21 out of 33 decomposed postmortem blood samples (64%) a total of 30 different strains could be isolated, one from the class of Ascomycete and the rest belonging to 15 species from 8 different genera (number of species): Aspergillus (2), Botrytis (1), Candida (8), Fusarium (1), Mucor (1), Penicillium (1), and Rodothorula (1). In the in vitro studies, these microorganisms were found capable of N-demethylation and N-oxidation of amitriptyline and mirtazapine, O-demethylation followed by side chain oxidation of metoprolol as well as hydroxylation of all four-model drugs. In two of the postmortem blood samples, from which the fungi Aspergillus jensenii, Candida parapsilosis. and Mucor circinelloides had been isolated, a fungi-specific hydroxy zolpidem metabolite was detected. The presence of this metabolite in postmortem samples likely indicates postmortem fungal biodegradation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Postmortem examination of Australian sea snakes ( Hydrophiinae): Anatomy and common pathologic conditions.

PubMed

Gillett, Amber K; Ploeg, Richard; Flint, Mark; Mills, Paul C

2017-09-01

There is limited published information about disease in wild sea snakes and no standardized guideline for postmortem examination of sea snakes. Identifying causes of morbidity and mortality of marine vertebrate species has been pivotal to understanding disease factors implicated in stranding events and assisting with the formulation of conservation plans. Additionally, postmortem findings can provide valuable information on life history traits and the ecology of these reclusive species. Sick, moribund, or dead sea snakes are intermittently washed ashore along Australian and international beaches and provide an opportunity to examine a subset of the population and identify causes of population decline. We present an illustrated description of sea snake anatomy and describe a systematic approach to postmortem examination of sea snakes. We describe common pathologic conditions identified from clinical and postmortem examinations of stranded Australian sea snakes from southeast Queensland. Notable pathologic conditions include traumatic injury, inflammatory conditions, parasitic infections, and neoplasia.

Postmortem aging can significantly enhance water-holding capacity of broiler pectoralis major muscle measured by the salt-induced swelling/centrifuge method

USDA-ARS?s Scientific Manuscript database

Water-holding capacity (WHC) is one of the most important functional properties of fresh meat and can be significantly affected by postmortem muscle changes. Two experiments were carried out to evaluate the effects of postmortem aging on WHC of broiler pectoralis (p.) major muscle indicated with % s...

Analysis of Sertraline in Postmortem Fluids and Tissues in 11 Aviation Accident Victims

DTIC Science & Technology

2012-11-01

likely undergoes significant postmortem redistribution. 17. Key Words 18. Distribution Statement Forensic Toxicology , Sertraline, Norsertraline... Toxicology .. Forensic Sci Int,.142:.75-100.(2004) . 29 .. Skopp,.G ..Postmortem.Toxicology .. Forensic Sci Med Pathol,.6:.314-25.(2010) . ... toxicological . analysis. on. specimens.from.….aircraft.accident.fatalities”.and.“in- vestigate.….general.aviation.and.air.carrier.accidents. and. search

Cardiac mesenchymal progenitors from postmortem cardiac tissues retained cellular characterization.

PubMed

Kami, D; Kitani, T; Nakata, M; Gojo, S

2014-05-01

Currently, cells for transplantation in regenerative medicine are derived from either autologous or allogeneic tissue. The former has the drawbacks that the quality of donor cells may depend on the condition of the patient, while the quantity of the cells may also be limited. To solve these problems, we investigated the potential of allogeneic cardiac mesenchymal progenitors (CMPs) derived from postmortem hearts, which may be immunologically privileged similar to bone marrow-derived mesenchymal progenitors. We examined whether viable CMPs could be isolated from C57/B6 murine cardiac tissues harvested at 24 hours postmortem. After 2- to 3-week propagation with a high dose of basic fibroblast growth factor, we performed cellular characteristics analyses, which included proliferation and differentiation property flow cytometry and microarray analyses. Postmortem CMPs had a longer lag phase after seeding than CMPs obtained from living tissues, but otherwise had similar characteristics in all the analyses. In addition, global gene expression analysis by microarray showed that cells derived from postmortem and living tissues had similar characteristics. These results indicate that allogeneic postmortem CMPs have potential for cell transplantation because they circumvent the issue of both the quality and quantity of donor cells. Copyright © 2014 Elsevier Inc. All rights reserved.

Utilization of bone impedance for age estimation in postmortem cases.

PubMed

Ishikawa, Noboru; Suganami, Hideki; Nishida, Atsushi; Miyamori, Daisuke; Kakiuchi, Yasuhiro; Yamada, Naotake; Wook-Cheol, Kim; Kubo, Toshikazu; Ikegaya, Hiroshi

2015-11-01

In the field of Forensic Medicine the number of unidentified cadavers has increased due to natural disasters and international terrorism. The age estimation is very important for identification of the victims. The degree of sagittal closure is one of such age estimation methods. However it is not widely accepted as a reliable method for age estimation. In this study, we have examined whether measuring impedance value (z-values) of the sagittal suture of the skull is related to the age in men and women and discussed the possibility to use bone impedance for age estimation. Bone impedance values increased with aging and decreased after the age of 64.5. Then we compared age estimation through the conventional visual method and the proposed bone impedance measurement technique. It is suggested that the bone impedance measuring technique may be of value to forensic science as a method of age estimation. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Prevention of abnormal pulmonary mechanics in the postmortem guinea pig lung.

PubMed

Reynolds, A M; McEvoy, R D

1988-04-01

Severe postmortem bronchoconstriction has been shown previously in guinea pig lungs and linked to pulmonary blood loss during exsanguination (Lai et al., J. Appl. Physiol. 56: 308-314, 1984). To reexamine this phenomenon we measured postmortem airway function in anesthetized open-chest guinea pigs after sudden circulatory arrest. Animals were divided into 4 groups of 10 and ventilated for 15 min postmortem with different gases: 1) room air, 2) conditioned air, 3) dry 5% CO2-21% O2-74% N2, and 4) conditioned 5% CO2-21% O2-74% N2. In room air-ventilated lungs there was a 50% decrease in dynamic compliance (Cdyn) by 15 min and marked gas trapping compared with control lungs. Conditioning the room air did not attenuate these changes, but when 5% CO2 was added to the conditioned postmortem inspirate, gas trapping was eliminated and the fall in Cdyn was almost abolished. Ventilation with a dry 5% CO2 gas mixture at room temperature resulted in a 31% fall in Cdyn at 15 min but no gas trapping. We conclude that marked abnormalities of airway function occur postmortem in room air-ventilated guinea pig lungs in the absence of pulmonary blood loss. The changes are mainly due to airway hypocarbia, a known cause of bronchoconstriction, but a reduction in Cdyn can also occur if there is marked airway cooling and drying. Acute postmortem airway dysfunction can be prevented in the guinea pig by maintaining normal airway gas composition.

Conceptual modeling of postmortem evaluation findings to describe dairy cow deaths.

PubMed

McConnel, C S; Garry, F B; Hill, A E; Lombard, J E; Gould, D H

2010-01-01

Dairy cow mortality levels in the United States are excessive and increasing over time. To better define cause and effect and combat rising mortality, clearer definitions of the reasons that cows die need to be acquired through thorough necropsy-based postmortem evaluations. The current study focused on organizing information generated from postmortem evaluations into a monitoring system that is based on the fundamentals of conceptual modeling and that will potentially be translatable into on-farm relational databases. This observational study was conducted on 3 high-producing, commercial dairies in northern Colorado. Throughout the study period a thorough postmortem evaluation was performed by veterinarians on cows that died on each dairy. Postmortem data included necropsy findings, life-history features (e.g., birth date, lactation number, lactational and reproductive status), clinical history and treatments, and pertinent aspects of operational management that were subject to change and considered integral to the poor outcome. During this study, 174 postmortem evaluations were performed. Postmortem evaluation results were conceptually modeled to view each death within the context of the web of factors influencing the dairy and the cow. Categories were formulated describing mortality in terms of functional characteristics potentially amenable to easy performance evaluation, management oversight, and research. In total, 21 death categories with 7 category themes were created. Themes included specific disease processes with variable etiologies, failure of disease recognition or treatment, traumatic events, multifactorial failures linked to transition or negative energy balance issues, problems with feed management, miscellaneous events not amenable to prevention or treatment, and undetermined causes. Although postmortem evaluations provide the relevant information necessary for framing a cow's death, a restructuring of on-farm databases is needed to integrate this level of detail into useful monitoring systems. Individual operations can focus on combating mortality through the use of employee training related to postmortem evaluations, detailed forms for capturing necropsy particulars and other relevant information related to deaths, and standardized nomenclature and categorization schemes. As much as anything, the simple act of recognizing mortality as a problem might be the most fundamental step toward controlling its progression. Copyright 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Relationship between water-holding capacity and protein denaturation in broiler breast meat.

PubMed

Bowker, B; Zhuang, H

2015-07-01

The objective of this study was to determine the relationship between water-holding capacity (WHC) attributes and protein denaturation in broiler breast meat. Boneless skinless breast fillets (n = 72) were collected from a commercial processing plant at 2 h postmortem and segregated into low-WHC and high-WHC groups based on muscle pH and color (L*a*b*). At 6 and 24 h postmortem, brine uptake (%), cooking loss (%), and protein solubility (sarcoplasmic and myofibrillar) were measured and protein fractions were analyzed using SDS-PAGE. Drip loss accumulation (%) was measured after storage for 2 and 7 days postmortem. High-WHC fillets exhibited lower L*-lightness values and greater pH values at 2 and 24 h postmortem than low-WHC fillets. High-WHC fillets had greater brine uptake and less cooking loss at both 6 and 24 h postmortem compared to low-WHC fillets. Aging from 6 to 24 h postmortem increased brine uptake in high-WHC fillets, but did not affect cooking loss in either low-WHC or high-WHC fillets. Drip loss accumulation was greater in low-WHC fillets at both 2 and 7 days postmortem. Myofibrillar protein solubility decreased with postmortem time but was not different between low-WHC and high-WHC fillets. Sarcoplasmic protein solubility increased with postmortem time and was greater in high-WHC fillets. SDS-PAGE analysis indicated that low-WHC fillets exhibited more glycogen phosphorylase denaturation than high-WHC fillets as evidenced by a more extensive shift of the protein from the sarcoplasmic to the myofibrillar protein fraction. Correlation analysis revealed that overall protein solubility measurements were not related to WHC attributes but that the degree of glycogen phosphorylase denaturation was significantly correlated (|r| = 0.52 to 0.80) to measures of WHC. Data indicated that WHC differences in broiler breast fillets were not due to differences in myofibrillar protein denaturation and suggested that the denaturation of sarcoplasmic proteins onto myofibrils may influence WHC in breast meat. © 2015 Poultry Science Association Inc.

Postmortem computed tomography and magnetic resonance imaging facilitates forensic autopsy in a fatal case of poisoning with formic acid, diphenhydramine, and ethanol.

PubMed

Berger, Florian; Steuer, Andrea E; Rentsch, Katharina; Gascho, Dominic; Stamou, Stamatios; Schärli, Sarah; Thali, Michael J; Krämer, Thomas; Flach, Patricia M

2016-09-01

A case of fatal poisoning by ingesting formic acid, diphenhydramine, and ethanol by a 25-year-old woman who committed suicide is presented. Prior to autopsy, postmortem computed tomography and postmortem magnetic resonance tomography were performed and revealed severe damage to the stomach, the left thoracic wall, and parts of the liver. Imaging detected acid-induced fluid-fluid level within the thoracic cavity (fat-equivalent fluid and necrotic pleural effusion). This case report illustrates that postmortem cross-sectional imaging may facilitate dissection of severely damaged or complex regions, and may provide additional information compared to autopsy and toxicological examinations alone.

Detection of the source of hemorrhage using postmortem computerized tomographic angiography in a case of a giant juvenile nasopharyngeal angiofibroma after surgical treatment.

PubMed

do Nascimento, Felipe Barjud Pereira; dos Santos, Glaucia Aparecida Bento; Melo, Nelson Almeida d'Ávila; Damasceno, Eduarda Bittencourt; Mauad, Thais

2015-09-01

Postmortem computerized tomographic angiography (PMCTA) has been increasingly used in forensic medicine to detect and locate the source of bleeding in cases of fatal acute hemorrhage. In this paper, we report a case of postoperative complication in a patient with a giant juvenile nasopharyngeal angiofibroma in which the source of bleeding was detected by PMCTA. A case description and evaluations of the pre- and postoperative exams, postmortem CT angiogram, and conventional autopsy results are provided. The source of bleeding was identified by postmortem CT angiography but not by conventional autopsy. The established protocol, injecting contrast medium into the femoral artery, was effective in identifying the source of bleeding. Postoperative bleeding is a rare and frequently fatal complication of juvenile nasopharyngeal angiofibroma. As a complement to conventional autopsy, postmortem angiography is a valuable tool for the detection of lethal acute hemorrhagic foci, and establishing a routine procedure for PMCTA may improve its efficiency.

Crack propagation in teeth: a comparison of perimortem and postmortem behavior of dental materials and cracks.

PubMed

Hughes, Cris E; White, Crystal A

2009-03-01

This study presents a new method for understanding postmortem heat-induced crack propagation patterns in teeth. The results demonstrate that patterns of postmortem heat-induced crack propagation differ from perimortem and antemortem trauma-induced crack propagation patterns. Dental material of the postmortem tooth undergoes dehydration leading to a shrinking and more brittle dentin material and a weaker dentin-enamel junction. Dentin intertubule tensile stresses are amplified by the presence of the pulp cavity, and initiates crack propagation from the internal dentin, through the dentin-enamel junction and lastly the enamel. In contrast, in vivo perimortem and antemortem trauma-induced crack propagation initiates cracking from the external surface of the enamel toward the dentin-enamel junction where the majority of the energy of the crack is dissipated, eliminating the crack's progress into the dentin. These unique patterns of crack propagation can be used to differentiate postmortem taphonomy-induced damage from antemortem and perimortem trauma in teeth.

Fatal fentanyl patch misuse in a hospitalized patient with a postmortem increase in fentanyl blood concentration.

PubMed

Moore, Philip W; Palmer, Robert B; Donovan, Joseph Ward

2015-01-01

Opioid-related mortality happens, even in healthcare settings. We describe serial postmortem fentanyl blood concentrations in a hospital inpatient who fatally abused transdermal fentanyl. This is a single-patient case report. A 42-year-old man with lymphoma was started on transdermal fentanyl therapy while hospitalized for chronic abdominal pain. The patient was last seen awake 1.3 h prior to being found apneic and cyanotic. During the resuscitation attempt, a small square-shaped film was removed from the patient's oropharynx. Femoral blood was collected 0.5 and 2 h postmortem, and the measured fentanyl concentration increased from 1.6 to 14 ng/mL. Study limitations include potential laboratory or collection errors and missing data. (i) Providers must be vigilant for signs of fentanyl patch abuse. (ii) Postmortem blood concentrations are not static postmortem, likely secondary to decreasing pH, increased aqueous solubility, and tissue redistribution, and are therefore unlikely to accurately represent antemortem blood concentrations. © 2014 American Academy of Forensic Sciences.

Postmortem clinical examination by experienced clinical geneticists as an alternative to conventional autopsy for assessment of fetal and perinatal deaths in countries with limited resources.

PubMed

Abdalla, Ebtesam M; El Desouky, Lubna M; Hassanein, Nargues M

2015-01-01

The aim of this study was to investigate the usefulness of postmortem external examination performed by an experienced clinical geneticist as an alternative to autopsy in countries with limited resources. We studied a consecutive cohort of couples seeking genetic counseling for fetal loss or perinatal death over a period of 3 years. The study involved 230 couples; only 57 of them submitted a fetus or dead neonate, for whom a meticulous postmortem clinical examination was performed by an experienced clinical geneticist. The diagnosis rate for the group of cases subjected to postmortem examination (57.9%) was much higher than that of the group that comprised cases for which diagnosis was made through evaluation of medical records (27.2%). Whenever fetal or neonatal autopsy is refused or is not feasible, a comprehensive fetal or perinatal postmortem external examination by an experienced clinical geneticist may be a reasonable substitute.

Mortality Patterns in Patients with Multiple Trauma: A Systematic Review of Autopsy Studies

PubMed Central

Pfeifer, Roman; Teuben, Michel; Andruszkow, Hagen; Barkatali, Bilal M.; Pape, Hans-Christoph

2016-01-01

Purpose A high percentage (50%-60%) of trauma patients die due to their injuries prior to arrival at the hospital. Studies on preclinical mortality including post-mortem examinations are rare. In this review, we summarized the literature focusing on clinical and preclinical mortality and studies included post-mortem examinations. Methods A literature search was conducted using PubMed/Medline database for relevant medical literature in English or German language published within the last four decades (1980–2015). The following MeSH search terms were used in different combinations: “multiple trauma”, “epidemiology”, “mortality “, “cause of death”, and “autopsy”. References from available studies were searched as well. Results Marked differences in demographic parameters and injury severity between studies were identified. Moreover, the incidence of penetrating injuries has shown a wide range (between 4% and 38%). Both unimodal and bimodal concepts of trauma mortality have been favored. Studies have shown a wide variation in time intervals used to analyze the distribution of death. Thus, it is difficult to say which distribution is correct. Conclusions We have identified variable results indicating bimodal or unimodal death distribution. Further more stundardized studies in this field are needed. We would like to encourage investigators to choose the inclusion criteria more critically and to consider factors affecting the pattern of mortality. PMID:26871937

[Excessive use of fentanyl patches as the only means of suicide].

PubMed

Wiesbrock, Urs O; Rochholz, Gertrud; Franzelius, Cornelia; Schwark, Thorsten; Grellner, Wolfgang

2008-01-01

Due to the increasing prescription there are more and more cases of abuse and accidents related to fentanyl patches. The use of fentanyl patches (e.g. Durogesic) for committing suicide is rare, however. In our case, we describe a suicide with an amount of fentanyl patches never mentioned in the literature before. A depressive 63-year-old man was found dead in his apartment. On the body of the decedent 20 nearly symmetrically arranged fentanyl patches (Durogesic) of different strength with a total dose of 1350 microg/h were found. According to the results of the police the fentanyl patches were part of the pain therapy of his late wife, who had died one year before. Neither the autopsy nor the histological examinations revealed a cause of death. The chemical-toxicological investigation showed the following fentanyl concentrations: 94.9 ng/g (femoral vein blood), 45.9 ng/g (blood of the left heart), 74.8 ng/g (blood of the right heart), 101 ng/mL (urine), 468 ng/mL (bile), 745 ng/mL (stomach contents), 78.4 ng/mL (cerebrospinal fluid), 133 ng/mL (vitreous humor). The blood concentrations were in the upper range of the concentrations found in similar cases published. Hints for a postmortem increase of the fentanyl concentration because of the long postmortem interval of nearly 8 days were found.

Postmortem Concentrations of Tramadol and O-Desmethyltramadol in 11 Aviation Accident Fatalities

DTIC Science & Technology

2010-12-01

Crump University of Central Oklahoma Edmond, OK 73034 December 2010 Final Report Postmortem Concentrations of Tramadol and O-Desmethyltramadol in...Subtitle 5. Report Date Postmortem Concentrations of Tramadol and O-Desmethyltramadol in 11 Aviation Accident Fatalities December 2010 6. Performing...This work was accomplished under the approved task AM-B-10-TOX-204. 16. Abstract Tramadol is a centrally acting analgesic used to treat moderate

Postmortem computed tomography findings in suicide victims.

PubMed

Garetier, M; Deloire, L; Dédouit, F; Dumousset, E; Saccardy, C; Ben Salem, D

2017-02-01

Suicide is the eighth cause of mortality in France and the leading cause in people aged between 25 and 34 years. The most common methods of suicide are hanging, self-poisoning with medicines and firearms. Postmortem computed tomography (CT) is a useful adjunct to autopsy to confirm suicide and exclude other causes of death. At autopsy, fractures of the hyoid bone or thyroid cartilage, or both, are found in more than 50% of suicidal hangings. Cervical vertebra fractures are rare and only seen in suicide victims jumping from a great height. Three-dimensional reconstructions from CT data are useful to visualize the ligature mark on the neck. In suicides by firearm, postmortem CT shows entry and exit wounds, parenchymal lesions along the bullet path, as well as projectiles in case of penetrating trauma. However, in the chest and abdomen it is more difficult to identify the path of the projectile. Postmortem CT also shows specific features of suicide by drowning or stabbing, but its use is limited in cases of self-poisoning. The use of postmortem CT is also limited by decomposition and change of body position. This article presents the imaging features seen on postmortem CT according to the method of suicide. Copyright © 2016 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

Influence of porcine circovirus type 2 vaccination on the probability and severity of pneumonia detected postmortem.

PubMed

Raith, J; Kuchling, S; Schleicher, C; Schobesberger, H; Köfer, J

2015-01-31

To evaluate the influence of porcine circovirus type 2 vaccination (PCV-2) on the probability and severity of pneumonia, postmortem findings of 247,505 pigs slaughtered between 2008 and 2011 were analysed by applying a cumulative link mixed model. Three major effects could be observed: (1) PCV-2 vaccination significantly (P<0.01) reduced the odds (coefficient: -0.05) of postmortem findings of mild, moderate and severe pneumonia for vaccinated pigs. (2) Pigs from fattening farms were less likely (coefficient: -0.44; P<0.05) to exhibit signs of pneumonia at slaughter than pigs from farrow-to-finish farms. (3) When vaccinated, the odds of detecting postmortem signs showed an even more pronounced reduction (coefficient: -0.19; P<0.001) for pigs from fattening farms. Combining PCV-2 vaccination, farm type and interaction effects between these two factors, a pig vaccinated against PCV-2 from a fattening farm had only half the chance (OR 0.51) of pneumonia being detected at postmortem than a non-vaccinated pig from a farrow-to-finish farm. The study demonstrates the benefit of a vaccination programme against PCV-2 as an important tool to reduce the risk of postmortem pneumonia findings and the severity of pneumonia in pigs at slaughter. British Veterinary Association.

Influence of porcine circovirus type 2 vaccination on the probability and severity of pneumonia detected postmortem

PubMed Central

Raith, J.; Kuchling, S.; Schleicher, C.; Schobesberger, H.; Köfer, J.

2015-01-01

To evaluate the influence of porcine circovirus type 2 vaccination (PCV-2) on the probability and severity of pneumonia, postmortem findings of 247,505 pigs slaughtered between 2008 and 2011 were analysed by applying a cumulative link mixed model. Three major effects could be observed: (1) PCV-2 vaccination significantly (P<0.01) reduced the odds (coefficient: −0.05) of postmortem findings of mild, moderate and severe pneumonia for vaccinated pigs. (2) Pigs from fattening farms were less likely (coefficient: −0.44; P<0.05) to exhibit signs of pneumonia at slaughter than pigs from farrow-to-finish farms. (3) When vaccinated, the odds of detecting postmortem signs showed an even more pronounced reduction (coefficient: −0.19; P<0.001) for pigs from fattening farms. Combining PCV-2 vaccination, farm type and interaction effects between these two factors, a pig vaccinated against PCV-2 from a fattening farm had only half the chance (OR 0.51) of pneumonia being detected at postmortem than a non-vaccinated pig from a farrow-to-finish farm. The study demonstrates the benefit of a vaccination programme against PCV-2 as an important tool to reduce the risk of postmortem pneumonia findings and the severity of pneumonia in pigs at slaughter. PMID:25413158

Reliability of postmortem fentanyl concentrations in determining the cause of death.

PubMed

Gill, James R; Lin, Peter T; Nelson, Lewis

2013-03-01

Transdermal fentanyl, an opioid used for management of marked pain, also is abused and may cause death. We reviewed medical examiner reports of 92 decedents who had one or more fentanyl transdermal patches on their body and had fentanyl detected in their postmortem toxicology analysis. The manners of death included 40 accidents, 36 natural, 8 suicides, 5 therapeutic complications, and 3 undetermined deaths. Among the accidental fentanyl intoxication deaths, 32 of 37 involved substance abuse. The majority (95 %) of the 37 accidental deaths involving fentanyl were multi-drug intoxications. The substance abuse deaths had a mean fentanyl blood concentration (26.4 ng/ml or μg/L) that was over twice that of the natural group (11.8 ng/ml). Our analysis suggests a relationship between total patch dosage and mean postmortem fentanyl concentration up to the 100-μg/h dose. The very wide and overlapping ranges of postmortem fentanyl concentrations effectively nullify the utility of correlating the dose and expected postmortem concentration for any particular death. Based on the variable relationship between dose and blood concentration, the antemortem dose cannot be reliably predicted based on the postmortem concentration. This does not, however, render the medical examiner/coroner unable to determine the cause and manner of death because the toxicology results are only one datum point among several that are considered. Although there was a weakly positive relationship between body mass index and fentanyl concentration, further research is needed to determine whether adipose tissue represents a significant depot for postmortem release of fentanyl.

Prescription opioid abuse based on representative postmortem toxicology.

PubMed

Häkkinen, Margareeta; Vuori, Erkki; Ojanperä, Ilkka

2014-12-01

Opioids are important medications for pain and opioid maintenance treatment. Increasing use and abuse of prescription opioids has, however, caused worldwide concern. Our aim was to estimate the ratio between prescription opioid abuse and total use, based on representative postmortem toxicology. Our material included all the medico-legally examined deaths in Finland during 2010-2011 involving positive findings involving buprenorphine, codeine, fentanyl, methadone, oxycodone, or tramadol. We studied drug abuse by age group, with "abuse" meaning licit opioids used illicitly as narcotics. Drug-abuse history, drug injecting, or laboratory findings of illicit drugs defined an abuser case. We then compared abuser cases and other opioid-related cases between the opioids with the number of fatal poisonings, accidents, suicides, alcohol findings, concomitant opioid use, and median postmortem blood opioid concentrations. Opioid findings numbered 2499 in 2088 cases. Drug abuse involved 545 opioid-positive cases, which in Finland represented 0.5% of those deceased. The proportion of abuser cases among all opioid-related cases for buprenorphine was 85.5%, for methadone 82.4%, for tramadol 29.4%, for codeine 16.3%, for fentanyl 14.5%, and for oxycodone 6.9%. Abuse in age-groups >60 was rare. Concomitant other opioid findings were more frequent in abuser- than in other cases for codeine, oxycodone, and tramadol, whereas alcohol findings were more frequent in buprenorphine, codeine, and fentanyl abuse. Buprenorphine and methadone were most often related to drug abuse. Every other opioid studied involved some abuse, and especially tramadol. Abuse and fatal poisonings were concentrated in men aged 20-49. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Variation in polyp size estimation among endoscopists and impact on surveillance intervals.

PubMed

Chaptini, Louis; Chaaya, Adib; Depalma, Fedele; Hunter, Krystal; Peikin, Steven; Laine, Loren

2014-10-01

Accurate estimation of polyp size is important because it is used to determine the surveillance interval after polypectomy. To evaluate the variation and accuracy in polyp size estimation among endoscopists and the impact on surveillance intervals after polypectomy. Web-based survey. A total of 873 members of the American Society for Gastrointestinal Endoscopy. Participants watched video recordings of 4 polypectomies and were asked to estimate the polyp sizes. Proportion of participants with polyp size estimates within 20% of the correct measurement and the frequency of incorrect surveillance intervals based on inaccurate size estimates. Polyp size estimates were within 20% of the correct value for 1362 (48%) of 2812 estimates (range 39%-59% for the 4 polyps). Polyp size was overestimated by >20% in 889 estimates (32%, range 15%-49%) and underestimated by >20% in 561 (20%, range 4%-46%) estimates. Incorrect surveillance intervals because of overestimation or underestimation occurred in 272 (10%) of the 2812 estimates (range 5%-14%). Participants in a private practice setting overestimated the size of 3 or of all 4 polyps by >20% more often than participants in an academic setting (difference = 7%; 95% confidence interval, 1%-11%). Survey design with the use of video clips. Substantial overestimation and underestimation of polyp size occurs with visual estimation leading to incorrect surveillance intervals in 10% of cases. Our findings support routine use of measurement tools to improve polyp size estimates. Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Re-establishment of rigor mortis: evidence for a considerably longer post-mortem time span.

PubMed

Crostack, Chiara; Sehner, Susanne; Raupach, Tobias; Anders, Sven

2017-07-01

Re-establishment of rigor mortis following mechanical loosening is used as part of the complex method for the forensic estimation of the time since death in human bodies and has formerly been reported to occur up to 8-12 h post-mortem (hpm). We recently described our observation of the phenomenon in up to 19 hpm in cases with in-hospital death. Due to the case selection (preceding illness, immobilisation), transfer of these results to forensic cases might be limited. We therefore examined 67 out-of-hospital cases of sudden death with known time points of death. Re-establishment of rigor mortis was positive in 52.2% of cases and was observed up to 20 hpm. In contrast to the current doctrine that a recurrence of rigor mortis is always of a lesser degree than its first manifestation in a given patient, muscular rigidity at re-establishment equalled or even exceeded the degree observed before dissolving in 21 joints. Furthermore, this is the first study to describe that the phenomenon appears to be independent of body or ambient temperature.

Veterinary Forensics: Firearms and Investigation of Projectile Injury.

PubMed

Bradley-Siemens, N; Brower, A I

2016-09-01

Projectile injury represents an estimated 14% of reported animal cruelty cases in the United States. Cases involving projectiles are complicated by gross similarities to other common types of injury, including bite wounds and motor vehicle injuries, by weapons and ammunition not commonly recognized or understood by veterinary medical professionals, and by required expertise beyond that employed in routine postmortem examination. This review describes the common types of projectile injuries encountered within the United States, as well as firearms and ammunition associated with this form of injury. The 3 stages of ballistics-internal, external, and terminal-and wounding capacity are discussed. A general understanding of firearms, ammunition, and ballistics is necessary before pursuing forensic projectile cases. The forensic necropsy is described, including gunshot wound examination, projectile trajectories, different imaging procedures, collection and storage of projectile evidence, and potential advanced techniques for gunpowder analysis. This review presents aspects of projectile injury investigation that must be considered in tandem with standard postmortem practices and procedures to ensure reliable conclusions are reached for medicolegal as well as diagnostic purposes. © The Author(s) 2016.

Morphology and developmental rate of blowflies Chrysomya megacephala and Chrysomya rufifacies in Thailand: application in forensic entomology.

PubMed

Sukontason, Kom; Piangjai, Somsak; Siriwattanarungsee, Sirisuda; Sukontason, Kabkaew L

2008-05-01

The larval morphology and developmental rate of Chrysomya megacephala (F.) and Chrysomya rufifacies (Macquart), the two most forensically important blowfly species in Thailand, are presented. Morphological comparison of the third instar of both species revealed different characteristics (e.g., body appearance, cephalopharyngeal skeleton, dorsal cuticular spines between the prothorax and mesothorax, and feature of the posterior spiracle), thereby, allowing correct identification. A data analysis was conducted in Chiang Mai province, Northern Thailand during 2000-2001 on the developmental rate of both flies under natural ambient temperature and a natural light-dark photoperiod. The results indicated that larvae of C. megacephala developed more rapidly in April, pupariation initiated at 84 h at temperatures averaging 31.4 degrees C, and the larvae grew slower in the rainy season and winter. Similarly, rapid development of C. rufifacies larvae appeared in the summer, with a pupariation period as short as 96 h in June (average temperature 27.4 degrees C). Analysis of the median body length of C. megacephala and C. rufifacies larvae in different seasons of the years 2000-2001 in Thailand revealed that both species developed rapidly in the summer; pupariation of C. rufifacies initiated at 144 h, while C. megacephala initiated pupariation at 156 h. This information is potentially useful for estimating the postmortem interval of a corpse in forensic investigations, where the corpse becomes infesting with these fly species.

Publication Bias in Meta-Analysis: Confidence Intervals for Rosenthal's Fail-Safe Number.

PubMed

Fragkos, Konstantinos C; Tsagris, Michail; Frangos, Christos C

2014-01-01

The purpose of the present paper is to assess the efficacy of confidence intervals for Rosenthal's fail-safe number. Although Rosenthal's estimator is highly used by researchers, its statistical properties are largely unexplored. First of all, we developed statistical theory which allowed us to produce confidence intervals for Rosenthal's fail-safe number. This was produced by discerning whether the number of studies analysed in a meta-analysis is fixed or random. Each case produces different variance estimators. For a given number of studies and a given distribution, we provided five variance estimators. Confidence intervals are examined with a normal approximation and a nonparametric bootstrap. The accuracy of the different confidence interval estimates was then tested by methods of simulation under different distributional assumptions. The half normal distribution variance estimator has the best probability coverage. Finally, we provide a table of lower confidence intervals for Rosenthal's estimator.

Publication Bias in Meta-Analysis: Confidence Intervals for Rosenthal's Fail-Safe Number

PubMed Central

Fragkos, Konstantinos C.; Tsagris, Michail; Frangos, Christos C.

2014-01-01

The purpose of the present paper is to assess the efficacy of confidence intervals for Rosenthal's fail-safe number. Although Rosenthal's estimator is highly used by researchers, its statistical properties are largely unexplored. First of all, we developed statistical theory which allowed us to produce confidence intervals for Rosenthal's fail-safe number. This was produced by discerning whether the number of studies analysed in a meta-analysis is fixed or random. Each case produces different variance estimators. For a given number of studies and a given distribution, we provided five variance estimators. Confidence intervals are examined with a normal approximation and a nonparametric bootstrap. The accuracy of the different confidence interval estimates was then tested by methods of simulation under different distributional assumptions. The half normal distribution variance estimator has the best probability coverage. Finally, we provide a table of lower confidence intervals for Rosenthal's estimator. PMID:27437470

Nonconsumptive Effects of Predatory Chrysomya rufifacies (Diptera: Calliphoridae) Larval Cues on Larval Cochliomyia macellaria (Diptera: Calliphoridae) Growth and Development.

PubMed

Flores, Micah; Crippen, Tawni L; Longnecker, Michael; Tomberlin, Jeffery K

2017-09-01

Forensic entomologists often rely on development data associated with a given species to estimate when it colonized human or other vertebrate remains. In most instances, these development studies are based on single species reared in isolation in the laboratory. This study examined the impact of excretions and secretions (ES) associated with third-instar Chrysomya rufifacies (Macquart), a predator, on the development of its prey, Cochliomyia macellaria (F.). Not surprisingly, Ch. rufifacies ES did not impact the development of first- or second-instar C. macellaria, which are typically not preyed on by Ch. rufifacies. However, development of third-instar C. macellaria, which do experience predation, was impacted. First, larvae were longer than those in the control (deionized water, dH2O). Filtering the ES and removing the associated bacteria and byproducts >0.2 µm dampened the previous impact observed by the unfiltered ES on third-instar C. macellaria. Second, third-instar C. macellaria treated with unfiltered ES completed pupariation 8 h quicker than the controls. Filtering the ES lessened this effect by 50%. And finally, third-instar C. macellaria treated with filtered or unfiltered Ch. rufifacies ES reached adulthood ∼5 h faster than controls treated with dH2O. In summary, these data have large ramifications for forensic entomology, as multiple species being present on decomposing remains is not uncommon. Understanding the impact of associated ES produced by interspecific cohorts on associated development could lead to more precise estimates of the minimum postmortem interval for forensic investigation of decomposing remains. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Investigating the impact of fasciolosis on cattle carcase performance.

PubMed

Sanchez-Vazquez, Manuel J; Lewis, Fraser I

2013-03-31

Liver fluke is a manifestation of bovine fasciolosis and its presence is compulsorily investigated as part of routine official abattoir inspections. It is known that the presence of fasciolosis negatively influences beef production, interfering with weight gain and fertility. Recent reports suggest increased occurrence of this parasite worldwide. This paper aims to investigate the impact of fasciolosis on beef cattle performance by examining the association of liver fluke with carcase characteristics and its value. Cattle slaughtered between 2005 and 2010 (328, 137 cattle (of which 12.6% were positive to liver fluke) sourced from 2278 farms) are analysed adjusting for the effect of gender, age, breed, season and year. Carcases with liver fluke have lower cold weight than those carcases free of fluke, estimated coefficient -0.63 kg (95% confidence intervals (CI) -0.93, -0.33). Carcases with liver fluke have lower price than those carcases free of fluke, estimated coefficient -£1.5 (95% CI -2.24, -0.74). The presence of liver fluke is associated with lower carcase conformation scores compared to carcases with fluke absence, proportional odds ratio (POR) 0.89 (95% CI 0.87-0.91). Similarly, the presence of liver fluke is associated with lower levels of fat in the carcase compared to carcases with fluke absence, POR 0.97 (95% CI 0.95-0.99). These results indicate a potential negative effect of the parasitism on carcase performance. The downgrading of the carcase impacts its value and therefore the price paid to the farmer. Both farmers and abattoir operators share a common interest in the control of fasciolosis in order to optimise the profitability of beef production. This study shows the utility of abattoir post-mortem inspection as a tool to monitoring animal health and production. Copyright © 2012 Elsevier B.V. All rights reserved.

Breast density quantification using magnetic resonance imaging (MRI) with bias field correction: A postmortem study

PubMed Central

Ding, Huanjun; Johnson, Travis; Lin, Muqing; Le, Huy Q.; Ducote, Justin L.; Su, Min-Ying; Molloi, Sabee

2013-01-01

Purpose: Quantification of breast density based on three-dimensional breast MRI may provide useful information for the early detection of breast cancer. However, the field inhomogeneity can severely challenge the computerized image segmentation process. In this work, the effect of the bias field in breast density quantification has been investigated with a postmortem study. Methods: T1-weighted images of 20 pairs of postmortem breasts were acquired on a 1.5 T breast MRI scanner. Two computer-assisted algorithms were used to quantify the volumetric breast density. First, standard fuzzy c-means (FCM) clustering was used on raw images with the bias field present. Then, the coherent local intensity clustering (CLIC) method estimated and corrected the bias field during the iterative tissue segmentation process. Finally, FCM clustering was performed on the bias-field-corrected images produced by CLIC method. The left–right correlation for breasts in the same pair was studied for both segmentation algorithms to evaluate the precision of the tissue classification. Finally, the breast densities measured with the three methods were compared to the gold standard tissue compositions obtained from chemical analysis. The linear correlation coefficient, Pearson's r, was used to evaluate the two image segmentation algorithms and the effect of bias field. Results: The CLIC method successfully corrected the intensity inhomogeneity induced by the bias field. In left–right comparisons, the CLIC method significantly improved the slope and the correlation coefficient of the linear fitting for the glandular volume estimation. The left–right breast density correlation was also increased from 0.93 to 0.98. When compared with the percent fibroglandular volume (%FGV) from chemical analysis, results after bias field correction from both the CLIC the FCM algorithms showed improved linear correlation. As a result, the Pearson's r increased from 0.86 to 0.92 with the bias field correction. Conclusions: The investigated CLIC method significantly increased the precision and accuracy of breast density quantification using breast MRI images by effectively correcting the bias field. It is expected that a fully automated computerized algorithm for breast density quantification may have great potential in clinical MRI applications. PMID:24320536

Breast density quantification using magnetic resonance imaging (MRI) with bias field correction: a postmortem study.

PubMed

Ding, Huanjun; Johnson, Travis; Lin, Muqing; Le, Huy Q; Ducote, Justin L; Su, Min-Ying; Molloi, Sabee

2013-12-01

Quantification of breast density based on three-dimensional breast MRI may provide useful information for the early detection of breast cancer. However, the field inhomogeneity can severely challenge the computerized image segmentation process. In this work, the effect of the bias field in breast density quantification has been investigated with a postmortem study. T1-weighted images of 20 pairs of postmortem breasts were acquired on a 1.5 T breast MRI scanner. Two computer-assisted algorithms were used to quantify the volumetric breast density. First, standard fuzzy c-means (FCM) clustering was used on raw images with the bias field present. Then, the coherent local intensity clustering (CLIC) method estimated and corrected the bias field during the iterative tissue segmentation process. Finally, FCM clustering was performed on the bias-field-corrected images produced by CLIC method. The left-right correlation for breasts in the same pair was studied for both segmentation algorithms to evaluate the precision of the tissue classification. Finally, the breast densities measured with the three methods were compared to the gold standard tissue compositions obtained from chemical analysis. The linear correlation coefficient, Pearson's r, was used to evaluate the two image segmentation algorithms and the effect of bias field. The CLIC method successfully corrected the intensity inhomogeneity induced by the bias field. In left-right comparisons, the CLIC method significantly improved the slope and the correlation coefficient of the linear fitting for the glandular volume estimation. The left-right breast density correlation was also increased from 0.93 to 0.98. When compared with the percent fibroglandular volume (%FGV) from chemical analysis, results after bias field correction from both the CLIC the FCM algorithms showed improved linear correlation. As a result, the Pearson's r increased from 0.86 to 0.92 with the bias field correction. The investigated CLIC method significantly increased the precision and accuracy of breast density quantification using breast MRI images by effectively correcting the bias field. It is expected that a fully automated computerized algorithm for breast density quantification may have great potential in clinical MRI applications.

Comparative assessment of 6-[18 F]fluoro-L-m-tyrosine and 6-[18 F]fluoro-L-dopa to evaluate dopaminergic presynaptic integrity in a Parkinson's disease rat model.

PubMed

Becker, Guillaume; Bahri, Mohamed Ali; Michel, Anne; Hustadt, Fabian; Garraux, Gaëtan; Luxen, André; Lemaire, Christian; Plenevaux, Alain

2017-05-01

Because of the progressive loss of nigro-striatal dopaminergic terminals in Parkinson's disease (PD), in vivo quantitative imaging of dopamine (DA) containing neurons in animal models of PD is of critical importance in the preclinical evaluation of highly awaited disease-modifying therapies. Among existing methods, the high sensitivity of positron emission tomography (PET) is attractive to achieve that goal. The aim of this study was to perform a quantitative comparison of brain images obtained in 6-hydroxydopamine (6-OHDA) lesioned rats using two dopaminergic PET radiotracers, namely [ 18 F]fluoro-3,4-dihydroxyphenyl-L-alanine ([ 18 F]FDOPA) and 6-[ 18 F]fluoro-L-m-tyrosine ([ 18 F]FMT). Because the imaging signal is theoretically less contaminated by metabolites, we hypothesized that the latter would show stronger relationship with behavioural and post-mortem measures of striatal dopaminergic deficiency. We used a within-subject design to measure striatal [ 18 F]FMT and [ 18 F]FDOPA uptake in eight partially lesioned, eight fully lesioned and ten sham-treated rats. Animals were pretreated with an L-aromatic amino acid decarboxylase inhibitor. A catechol-O-methyl transferase inhibitor was also given before [ 18 F]FDOPA PET. Quantitative estimates of striatal uptake were computed using conventional graphical Patlak method. Striatal dopaminergic deficiencies were measured with apomorphine-induced rotations and post-mortem striatal DA content. We observed a strong relationship between [ 18 F]FMT and [ 18 F]FDOPA estimates of decreased uptake in the denervated striatum using the tissue-derived uptake rate constant K c . However, only [ 18 F]FMT K c succeeded to discriminate between the partial and the full 6-OHDA lesion and correlated well with the post-mortem striatal DA content. This study indicates that the [ 18 F]FMT could be more sensitive, with respect of [ 18 F]FDOPA, to investigate DA terminals loss in 6-OHDA rats, and open the way to in vivo L-aromatic amino acid decarboxylase activity targeting in future investigations on progressive PD models. © 2017 International Society for Neurochemistry.

Characterisation of the metabolome of ocular tissues and post-mortem changes in the rat retina.

PubMed

Tan, Shi Z; Mullard, Graham; Hollywood, Katherine A; Dunn, Warwick B; Bishop, Paul N

2016-08-01

Time-dependent post-mortem biochemical changes have been demonstrated in donor cornea and vitreous, but there have been no published studies to date that objectively measure post-mortem changes in the retinal metabolome over time. The aim of the study was firstly, to investigate post-mortem, time-dependent changes in the rat retinal metabolome and secondly, to compare the metabolite composition of healthy rat ocular tissues. To study post-mortem changes in the rat retinal metabolome, globes were enucleated and stored at 4 °C and sampled at 0, 2, 4, 8, 24 and 48 h post-mortem. To study the metabolite composition of rat ocular tissues, eyes were dissected immediately after culling to isolate the cornea, lens, vitreous and retina, prior to storing at -80 °C. Tissue extracts were subjected to Gas Chromatograph Mass Spectrometry (GC-MS) and Ultra High Performance Liquid Chromatography Mass Spectrometry (UHPLC-MS). Generally, the metabolic composition of the retina was stable for 8 h post-mortem when eyes were stored at 4 °C, but showed increasing changes thereafter. However, some more rapid changes were observed such as increases in TCA cycle metabolites after 2 h post-mortem, whereas some metabolites such as fatty acids only showed decreases in concentration from 24 h. A total of 42 metabolites were identified across the ocular tissues by GC-MS (MSI level 1) and 2782 metabolites were annotated by UHPLC-MS (MSI level 2) according to MSI reporting standards. Many of the metabolites detected were common to all of the tissues but some metabolites showed partitioning between different ocular structures with 655, 297, 93 and 13 metabolites being uniquely detected in the retina, lens, cornea and vitreous respectively. Only a small percentage (1.6%) of metabolites found in the vitreous were only detected in the retina and not other tissues. In conclusion, mass spectrometry-based techniques have been used for the first time to compare the metabolic composition of different ocular tissues. The metabolite composition of the retina stored at 4 °C post-mortem is mostly stable for at least 8 h. Copyright © 2016 Elsevier Ltd. All rights reserved.

Post-mortem quetiapine concentrations in hair segments of psychiatric patients - Correlation between hair concentration, dose and concentration in blood.

PubMed

Günther, Kamilla Nyborg; Johansen, Sys Stybe; Nielsen, Marie Katrine Klose; Wicktor, Petra; Banner, Jytte; Linnet, Kristian

2018-04-01

Drug analysis in hair is useful when seeking to establish drug intake over a period of months to years. Segmental hair analysis can also document whether psychiatric patients are receiving a stable intake of antipsychotics. This study describes segmental analysis of the antipsychotic drug quetiapine in post-mortem hair samples from long-term quetiapine users by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis. The aim was to obtain more knowledge on quetiapine concentrations in hair and to relate the concentration in hair to the administered dose and the post-mortem concentration in femoral blood. We analyzed hair samples from 22 deceased quetiapine-treated individuals, who were divided into two groups: natural hair colour and dyed/bleached hair. Two to six 1cm long segments were analyzed per individual, depending on the length of the hair, with 6cm corresponding to the last six months before death. The average daily quetiapine dose and average concentration in hair for the last six months prior to death were examined for potential correlation. Estimated doses ranged from 45 to 1040mg quetiapine daily over the period, and the average concentration in hair ranged from 0.18 to 13ng/mg. A significant positive correlation was observed between estimated daily dosage of quetiapine and average concentration in hair for individuals with natural hair colour (p=0.00005), but statistical significance was not reached for individuals with dyed/bleached hair (p=0.31). The individual coefficient of variation (CV) of the quetiapine concentrations between segments ranged from 3 to 34% for individuals with natural hair colour and 22-62% for individuals with dyed/bleached hair. Dose-adjusted concentrations in hair were significantly lower in females with dyed/bleached hair than in individuals with natural hair colour. The quetiapine concentrations in post-mortem femoral blood and in the proximal hair segment, segment 1 (S1), representing the last month before death were also investigated for correlation. A significant positive correlation was observed between quetiapine concentrations in blood at the time of death and concentrations in S1 for individuals with natural hair colour (p=0.003) but not for individuals with dyed/bleached hair (p=0.31). The blood concentrations of quetiapine ranged from 0.006 to 1.9mg/kg, and the quetiapine concentrations in S1 ranged from 0.22 to 24ng/mg. The results of this study suggest a positive correlation of quetiapine between both concentrations in hair and doses, and between proximal hair (S1) and blood concentrations, when conditions such as hair treatments are taken into consideration. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of probiotics feeding on meat quality of chicken breast during postmortem storage.

PubMed

Kim, H W; Yan, F F; Hu, J Y; Cheng, H W; Kim, Y H B

2016-06-01

This study evaluated the effects of dietary probiotic supplement and postmortem storage on meat quality of chicken breast during retail display. A total of 35 birds were randomly obtained from 3 feeding groups (control without probiotic supplement, 250 ppm Sporulin, and 500 ppm PoultryStar). The probiotic supplement had no influence on feed conversion ratio and body weight gain, as well as body weight at 29 and 44 d (P > 0.05). After slaughter, each side of the breast muscles (M. Pectoralis major) was assigned to either one d or 5 d of postmortem storage. Probiotic supplement had no influence on the rate of pH decline of chicken breast muscles during the initial 6 h postmortem (P > 0.05). No interactions between probiotic supplement and postmortem storage on meat quality were found (P > 0.05). Postmortem storage decreased drip loss from 25.30 to 18.05% (P < 0.05). Probiotics-fed chicken groups, particularly PoultryStar treatment, had a higher myofibrillar fragmentation index than the control group (P < 0.05). However, shear force values were not affected by the probiotic treatments. Decreases in color and lipid stabilities of breast muscles were found during display (P < 0.05), but were not affected by the probiotic supplement (P > 0.05). Our result suggests that probiotic supplement had no adverse impacts on proteolysis and oxidative changes during 5 d postmortem display storage. Published by Oxford University Press on behalf of Poultry Science Association 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Nitrobenzodiazepines: Postmortem brain and blood reference concentrations.

PubMed

Skov, Louise; Holm, Karen Marie Dollerup; Linnet, Kristian

2016-11-01

Reference concentrations are needed to evaluate postmortem toxicology results and usually femoral blood is the specimen of choice. However, brain tissue has been suggested as a viable alternative specimen, since postmortem blood concentrations can be difficult to interpret due to postmortem redistribution, among other factors. Here we present reference concentrations of postmortem brain and femoral blood of the nitrobenzodiazepines clonazepam, flunitrazepam, and nitrazepam that are of particular interest since they commonly are converted to their corresponding 7-aminometabolites in the postmortem situation. The drugs and metabolites were quantified in both matrices using LC-MS-MS in 69 cases. In 63 cases the compounds were judged not to have been of significance for the death (C cases), whereas they were considered to have been a contributing factor in 6 cases (B cases). No cases were observed with a nitrobenzodiazepine being the sole cause of death (A cases). The brain-blood ratios for clonazepam and nitrazepam were 5.5 and 4.7, respectively, while the brain-blood ratios for the 7-aminometabolites ranged from 0.4 to 0.5. Flunitrazepam only occurred as the 7-aminometabolite. A positive correlation between brain and blood concentrations was found with Spearman's rank correlation coefficients (r s ) ranging from 0.77 to 0.96. The measured femoral blood concentrations agree with literature values, but only few brain concentrations were available for comparison. The drug-metabolite ratios for clonazepam and nitrazepam were 10-12 times higher in brain than in blood. The pre-analytical variation in brain of 5.9% was fairly low, suggesting that brain tissue is a useful alternative to blood. The reported brain and femoral blood concentrations serve as reference values in postmortem investigations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The social life of the dead: The role of post-mortem examinations in medical student socialisation.

PubMed

Goodwin, Dawn; Machin, Laura; Taylor, Adam

2016-07-01

Dissection has held a privileged position in medical education although the professional values it inculcates have been subject to intense debate. Claims vary from it generating a dehumanising level of emotional detachment, to promotion of rational and dispassionate decision-making, even to being a positive vehicle for ethical education. Social scientists have positioned dissection as a critical experience in the emotional socialisation of medical students. However, curricular revision has provoked debate about the style and quantity of anatomy teaching thus threatening this 'rite of passage' of medical students. Consequently, some UK medical schools do not employ dissection at all. In its place, observation of post-mortem examinations - a long established, if underutilised, practice - has re-emerged in an attempt to recoup aspects of anatomical knowledge that are arguably lost when dissection is omitted. Bodies for post-mortem examinations and bodies for dissection, however, have striking differences, meaning that post-mortem examinations and dissection cannot be considered comparable opportunities to learn anatomy. In this article, we explore the distinctions between dissection and post-mortem examinations. In particular, we focus on the absence of a discourse of consent, concerns about bodily integrity, how the body's shifting ontology, between object and person, disrupts students' attempts to distance themselves, and how the observation of post-mortem examinations features in the emotional socialisation of medical students. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of fast pH decline during the early postmortem period on calpain activity and cytoskeletal protein degradation of broiler M. pectoralis major.

PubMed

Huang, J C; Yang, J; Huang, F; Huang, M; Chen, K J; Xu, X L; Zhou, G H

2016-10-01

The objective of this study was to determine the effects of fast pH decline during the early postmortem period on calpain activity and the degradation of cytoskeletal proteins in broilers. Eighty broilers were randomly categorized into two groups: physical restraint (PR) and free struggle (FS). M. pectoralis major (PM) was used for determination of calpain activity, shear value, ultrastructure of myofibrils, and the degradation of desmin, titin, nebulin, and troponin-T. The pH (6.05) of FS group is significantly low than PR group (6.38) at 0.3 h postmortem. Fast pH decline during the early postmortem period led to a decrease of μ/m-calpain activities at 0.3 and 3 h postmortem (P < 0.05), but did not affect the ultimate μ/m-calpain activity. An initial fast decrease in pH increased the degradation of desmin, titin, nebulin, and increased the 30 kDa degradation fragments of troponin-T. Therefore, the fast pH decline during the early postmortem period decreased the μ/m-calpain activity and increased the degradation of cytoskeletal proteins in broiler muscle. It is possible that the fast pH decline experienced an earlier activation of calpains that resulted in earlier protein degradation and ultimately lower shear force. © 2016 Poultry Science Association Inc.

Consensus recommendations for the postmortem diagnosis of Alzheimer's disease. The National Institute on Aging, and Reagan Institute Working Group on Diagnostic Criteria for the Neuropathological Assessment of Alzheimer's Disease.

PubMed

1997-01-01

This report summarizes the consensus recommendations of a panel of neuropathologists from the United States and Europe to improve the postmortem diagnostic criteria for Alzheimer's disease. The recommendations followed from a two-day workshop sponsored by the National Institute on Aging (NIA) and the Ronald and Nancy Reagan Institute of the Alzheimer's Association to reassess the original NIA criteria for the postmortem diagnosis of Alzheimer's disease published in 1985. The consensus recommendations for improving the neuropathological criteria for the postmortem diagnosis of Alzheimer's disease are reported here, and the "position papers" by members of the Working Group that accompany this report elaborate on the research findings and concepts upon which these recommendations were based. Further, commentaries by other experts in the field also are included here to provide additional perspectives on these recommendations. Finally, it is anticipated that future meetings of the Working Group will reassess these recommendations and the implementation of postmortem diagnostic criteria for Alzheimer's disease.

When does the lung die? Kfc, cell viability, and adenine nucleotide changes in the circulation-arrested rat lung.

PubMed

Jones, D R; Becker, R M; Hoffmann, S C; Lemasters, J J; Egan, T M

1997-07-01

Lungs harvested from cadaveric circulation-arrested donors may increase the donor pool for lung transplantation. To determine the degree and time course of ischemia-reperfusion injury, we evaluated the effect of O2 ventilation on capillary permeability [capillary filtration coefficient (Kfc)], cell viability, and total adenine nucleotide (TAN) levels in in situ circulation-arrested rat lungs. Kfc increased with increasing postmortem ischemic time (r = 0.88). Lungs ventilated with O2 1 h postmortem had similar Kfc and wet-to-dry ratios as controls. Nonventilated lungs had threefold (P < 0.05) and sevenfold (P < 0.0001) increases in Kfc at 30 and 60 min postmortem compared with controls. Cell viability decreased in all groups except for 30-min postmortem O2-ventilated lungs. TAN levels decreased with increasing ischemic time, particularly in nonventilated lungs. Loss of adenine nucleotides correlated with increasing Kfc values (r = 0.76). This study indicates that lungs retrieved 1 h postmortem may have normal Kfc with preharvest O2 ventilation. The relationship between Kfc and TAN suggests that vascular permeability may be related to lung TAN levels.

An Introduction to Confidence Intervals for Both Statistical Estimates and Effect Sizes.

ERIC Educational Resources Information Center

Capraro, Mary Margaret

This paper summarizes methods of estimating confidence intervals, including classical intervals and intervals for effect sizes. The recent American Psychological Association (APA) Task Force on Statistical Inference report suggested that confidence intervals should always be reported, and the fifth edition of the APA "Publication Manual"…

Lower Leg Injury Reference Values and Risk Curves from Survival Analysis for Male and Female Dummies: Meta-analysis of Postmortem Human Subject Tests.

PubMed

Yoganandan, Narayan; Arun, Mike W J; Pintar, Frank A; Banerjee, Anjishnu

2015-01-01

Derive lower leg injury risk functions using survival analysis and determine injury reference values (IRV) applicable to human mid-size male and small-size female anthropometries by conducting a meta-analysis of experimental data from different studies under axial impact loading to the foot-ankle-leg complex. Specimen-specific dynamic peak force, age, total body mass, and injury data were obtained from tests conducted by applying the external load to the dorsal surface of the foot of postmortem human subject (PMHS) foot-ankle-leg preparations. Calcaneus and/or tibia injuries, alone or in combination and with/without involvement of adjacent articular complexes, were included in the injury group. Injury and noninjury tests were included. Maximum axial loads recorded by a load cell attached to the proximal end of the preparation were used. Data were analyzed by treating force as the primary variable. Age was considered as the covariate. Data were censored based on the number of tests conducted on each specimen and whether it remained intact or sustained injury; that is, right, left, and interval censoring. The best fits from different distributions were based on the Akaike information criterion; mean and plus and minus 95% confidence intervals were obtained; and normalized confidence interval sizes (quality indices) were determined at 5, 10, 25, and 50% risk levels. The normalization was based on the mean curve. Using human-equivalent age as 45 years, data were normalized and risk curves were developed for the 50th and 5th percentile human size of the dummies. Out of the available 114 tests (76 fracture and 38 no injury) from 5 groups of experiments, survival analysis was carried out using 3 groups consisting of 62 tests (35 fracture and 27 no injury). Peak forces associated with 4 specific risk levels at 25, 45, and 65 years of age are given along with probability curves (mean and plus and minus 95% confidence intervals) for PMHS and normalized data applicable to male and female dummies. Quality indices increased (less tightness-of-fit) with decreasing age and risk level for all age groups and these data are given for all chosen risk levels. These PMHS-based probability distributions at different ages using information from different groups of researchers constituting the largest body of data can be used as human tolerances to lower leg injury from axial loading. Decreasing quality indices (increasing index value) at lower probabilities suggest the need for additional tests. The anthropometry-specific mid-size male and small-size female mean human risk curves along with plus and minus 95% confidence intervals from survival analysis and associated IRV data can be used as a first step in studies aimed at advancing occupant safety in automotive and other environments.

Usefulness and limitations of postmortem computed tomography in forensic analysis of gunshot injuries: Three case reports.

PubMed

Usui, Akihito; Kawasumi, Yusuke; Hosokai, Yoshiyuki; Kozakai, Masataka; Saito, Haruo; Funayama, Masato

2016-01-01

Gunshot injury has always been an important field of investigation in postmortem forensic radiology. The localization and retrieval of the bullet and of potentially important fragments are vital to these cases. Using postmortem multidetector-row computed tomography (MDCT) prior to forensic autopsy, we sought to illustrate the importance of this modality in the noninvasive characterization of gunshot wounds. We obtained and analyzed MDCT images in three cases of gunshot wounds (accidental close-range shotgun shooting, suicidal contact gunshot to the head and accidental long-range buckshot shooting). We discuss the value of postmortem MDCT findings in gunshot wound cases by comparing with forensic autopsy findings in Japan, a developing country with miserably low autopsy rate. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Examination of forensic entomology evidence using computed tomography scanning: case studies and refinement of techniques for estimating maggot mass volumes in bodies.

PubMed

Johnson, Aidan; Archer, Melanie; Leigh-Shaw, Lyndie; Pais, Mike; O'Donnell, Chris; Wallman, James

2012-09-01

A new technique has recently been developed for estimating the volume of maggot masses on deceased persons using post-mortem CT scans. This allows volume to be measured non-invasively and factored into maggot mass temperature calculations for both casework and research. Examination of admission scans also allows exploration of entomological evidence in anatomical areas not usually exposed by autopsy (e.g. nasal cavities and facial sinuses), and before autopsy disrupts the maggot distribution on a body. This paper expands on work already completed by providing the x-ray attenuation coefficient by way of Hounsfield unit (HU) values for various maggot species, maggot masses and human tissue adjacent to masses. Specifically, this study looked at the HU values for four forensically important blowfly larvae: Lucilia cuprina, L. sericata, Calliphora stygia and C. vicina. The Calliphora species had significantly lower HU values than the Lucilia species. This might be explained by histological analysis, which revealed a non-significant trend, suggesting that Calliphora maggots have a higher fat content than the Lucilia maggots. It is apparent that the variation in the x-ray attenuation coefficient usually precludes its use as a tool for delineating the maggot mass from human tissue and that morphology is the dominant method for delineating a mass. This paper also includes three case studies, which reveal different applications for interpreting entomological evidence using post-mortem CT scans.

Simpler and equitable allocation of kidneys from postmortem donors primarily based on full HLA-DR compatibility.

PubMed

Doxiadis, Ilias I N; de Fijter, Johan W; Mallat, Marko J K; Haasnoot, Geert W; Ringers, Jan; Persijn, Guido G; Claas, Frans H J

2007-05-15

The introduction of human leukocyte antigen (HLA)-matching in nonliving kidney transplantation has resulted into a better graft outcome, but also in an increase of waiting time, especially for patients with rare HLA phenotypes. We addressed the question of the differential influence of HLA-DR-matching versus HLA-A,B in clinical kidney transplantation. We used Kaplan-Meier product limit method to estimate survival rates, and Cox proportional hazard regression for the estimation of relative risks (Hazard-ratios) for different variables. A single center study (n=456 transplants, performed between 1985 and 1999) showed that full HLA-DR compatibility leads to a lower incidence of biopsy confirmed acute rejections in the first 180 posttransplantation days. These results were substantiated using the Eurotransplant database (n=39,205 transplants performed between 1985 and 2005) where graft survival in the full HLA-DR compatible group was significantly better than in the incompatible. An additional positive effect of HLA-A,B matching was only found in the full HLA-DR compatible group. In both studies, the introduction of a single HLA-DR incompatibility eliminates the HLA-A,B matching effect. We propose to allocate postmortem kidneys only to patients with full HLA-DR compatibility, and use HLA-A,B compatibility as an additional selection criterion. All patients, irrespective of their ethnic origin, will profit since the polymorphism of HLA-DR is by far lower than that of HLA-A,B. Excessive kidney travel and cold ischemia time will be significantly reduced.

Interval Estimation of Seismic Hazard Parameters

NASA Astrophysics Data System (ADS)

Orlecka-Sikora, Beata; Lasocki, Stanislaw

2017-03-01

The paper considers Poisson temporal occurrence of earthquakes and presents a way to integrate uncertainties of the estimates of mean activity rate and magnitude cumulative distribution function in the interval estimation of the most widely used seismic hazard functions, such as the exceedance probability and the mean return period. The proposed algorithm can be used either when the Gutenberg-Richter model of magnitude distribution is accepted or when the nonparametric estimation is in use. When the Gutenberg-Richter model of magnitude distribution is used the interval estimation of its parameters is based on the asymptotic normality of the maximum likelihood estimator. When the nonparametric kernel estimation of magnitude distribution is used, we propose the iterated bias corrected and accelerated method for interval estimation based on the smoothed bootstrap and second-order bootstrap samples. The changes resulted from the integrated approach in the interval estimation of the seismic hazard functions with respect to the approach, which neglects the uncertainty of the mean activity rate estimates have been studied using Monte Carlo simulations and two real dataset examples. The results indicate that the uncertainty of mean activity rate affects significantly the interval estimates of hazard functions only when the product of activity rate and the time period, for which the hazard is estimated, is no more than 5.0. When this product becomes greater than 5.0, the impact of the uncertainty of cumulative distribution function of magnitude dominates the impact of the uncertainty of mean activity rate in the aggregated uncertainty of the hazard functions. Following, the interval estimates with and without inclusion of the uncertainty of mean activity rate converge. The presented algorithm is generic and can be applied also to capture the propagation of uncertainty of estimates, which are parameters of a multiparameter function, onto this function.

Forensic dental age estimation by measuring root dentin translucency area using a new digital technique.

PubMed

Acharya, Ashith B

2014-05-01

Dentin translucency measurement is an easy yet relatively accurate approach to postmortem age estimation. Translucency area represents a two-dimensional change and may reflect age variations better than length. Manually measuring area is challenging and this paper proposes a new digital method using commercially available computer hardware and software. Area and length were measured on 100 tooth sections (age range, 19-82 years) of 250 μm thickness. Regression analysis revealed lower standard error of estimate and higher correlation with age for length than for area (R = 0.62 vs. 0.60). However, test of regression formulae on a control sample (n = 33, 21-85 years) showed smaller mean absolute difference (8.3 vs. 8.8 years) and greater frequency of smaller errors (73% vs. 67% age estimates ≤ ± 10 years) for area than for length. These suggest that digital area measurements of root translucency may be used as an alternative to length in forensic age estimation. © 2014 American Academy of Forensic Sciences.

Estimation of flood discharges at selected recurrence intervals for streams in New Hampshire.

DOT National Transportation Integrated Search

2008-01-01

This report provides estimates of flood discharges at selected recurrence intervals for streamgages in and adjacent to New Hampshire and equations for estimating flood discharges at recurrence intervals of 2-, 5-, 10-, 25-, 50-, 100-, and 500-years f...

Communicating with families about post-mortems: practice guidance.

PubMed

Henderson, Nicola

2006-02-01

In January 2001 the Chief Medical Officer announced the Public Inquiry (Redfern Report) into post-mortem practice at Alder Hey Hospital in Liverpool. It was expected that this inquiry report would influence post-mortem practice in general and communication with parents in particular and in May 2003 a code of practice for clinical staff was produced by the Department of Health (DH) (2003a). This article discusses the code of practice Families and Post Mortems and explores the relevance of these recommendations to neonatal and children's nurses.

Investigation of Post-mortem Tissue Effects Using Long-time Decorrelation Ultrasound

NASA Astrophysics Data System (ADS)

Csány, Gergely; Balogh, Lajos; Gyöngy, Miklós

Decorrelation ultrasound is being increasingly used to investigate long-term biological phenomena. In the current work, ultrasound image sequences of mice who did not survive anesthesia (in a separate investigation) were analyzed and post-mortem tissue effects were observed via decorrelation calculation. A method was developed to obtain a quantitative parameter characterizing the rate of decorrelation. The results show that ultrasound decorrelation imaging is an effective method of observing post-mortem tissue effects and point to further studies elucidating the mechanism behind these effects.

On Some Confidence Intervals for Estimating the Mean of a Skewed Population

ERIC Educational Resources Information Center

Shi, W.; Kibria, B. M. Golam

2007-01-01

A number of methods are available in the literature to measure confidence intervals. Here, confidence intervals for estimating the population mean of a skewed distribution are considered. This note proposes two alternative confidence intervals, namely, Median t and Mad t, which are simple adjustments to the Student's t confidence interval. In…

Confidence Intervals for Proportion Estimates in Complex Samples. Research Report. ETS RR-06-21

ERIC Educational Resources Information Center

Oranje, Andreas

2006-01-01

Confidence intervals are an important tool to indicate uncertainty of estimates and to give an idea of probable values of an estimate if a different sample from the population was drawn or a different sample of measures was used. Standard symmetric confidence intervals for proportion estimates based on a normal approximation can yield bounds…

Estimation of population divergence times from non-overlapping genomic sequences: examples from dogs and wolves.

PubMed

Skoglund, Pontus; Götherström, Anders; Jakobsson, Mattias

2011-04-01

Despite recent technological advances in DNA sequencing, incomplete coverage remains to be an issue in population genomics, in particular for studies that include ancient samples. Here, we describe an approach to estimate population divergence times for non-overlapping sequence data that is based on probabilities of different genealogical topologies under a structured coalescent model. We show that the approach can be adapted to accommodate common problems such as sequencing errors and postmortem nucleotide misincorporations, and we use simulations to investigate biases involved with estimating genealogical topologies from empirical data. The approach relies on three reference genomes and should be particularly useful for future analysis of genomic data that comprise of nonoverlapping sets of sequences, potentially from different points in time. We applied the method to shotgun sequence data from an ancient wolf together with extant dogs and wolves and found striking resemblance to previously described fine-scale population structure among dog breeds. When comparing modern dogs to four geographically distinct wolves, we find that the divergence time between dogs and an Indian wolf is smallest, followed by the divergence times to a Chinese wolf and a Spanish wolf, and a relatively long divergence time to an Alaskan wolf, suggesting that the origin of modern dogs is somewhere in Eurasia, potentially southern Asia. We find that less than two-thirds of all loci in the boxer and poodle genomes are more similar to each other than to a modern gray wolf and that--assuming complete isolation without gene flow--the divergence time between gray wolves and modern European dogs extends to 3,500 generations before the present, corresponding to approximately 10,000 years ago (95% confidence interval [CI]: 9,000-13,000). We explicitly study the effect of gene flow between dogs and wolves on our estimates and show that a low rate of gene flow is compatible with an even earlier domestication date ∼30,000 years ago (95% CI: 15,000-90,000). This observation is in agreement with recent archaeological findings and indicates that human behavior necessary for domestication of wild animals could have appeared much earlier than the development of agriculture.

Rabies Situation in Cambodia

PubMed Central

Ly, Sowath; Buchy, Philippe; Heng, Nay Yim; Ong, Sivuth; Chhor, Nareth; Bourhy, Hervé; Vong, Sirenda

2009-01-01

Background Rabies, a fatal but preventable zoonosis, is a major public health problem in developing countries. In Cambodia the disease burden is largely underestimated because patients with encephalitis following dog bites are rarely hospitalized and die at home. Since 1998 Institut Pasteur in Cambodia (IPC), Phnom Penh has been the only source of free post-exposure prophylaxis (PEP) and post-mortem diagnosis. Methods The 1998–2007 data compiled by IPC was analyzed to describe all treated patients for PEP, results of human testing and confirmed rabies cases, and results of animal testing. From dog bites' characteristics, we defined a suspected rabid dog bite injury (SRDBI) in humans as a bite that was unprovoked, from a dog that died spontaneously, or from a dog that was reported sick. We applied a deterministic probability model to estimate 2007 rabies human mortality nationwide from the estimated incidence of rabid dog bites, the body distribution of bite wounds, and the probability of PEP access. Results During 1998–2007, 124,749 patients received PEP at IPC (average 12,470; range 8,907–14,475), and 63 fatal human cases presenting with encephalitis following a dog bite were reported, in which 73% were confirmed positive for rabies by direct immunofluorescence assay or by reverse-transcriptase polymerase chain reaction. During 1998–2007, IPC tested 1,255 animal brain samples; 1,214 (97%) were from dogs including 610 (49%) positive samples. In 2007, 14,475 patients received PEP (100 PEP/100,000 people in Cambodia) including 95% who resided in Phnom Penh (615 PEP/100,000) or five neighboring provinces. The predictive model estimated 810 human rabies deaths would occur in 2007 (95%confidence interval [CI] 394–1,607), an incidence of 5.8/100,000 (95% CI 2.8–11.5). Conclusions Access to PEP is only sufficient for Phnom Penh residents. In 2007, the estimated rabies related mortality exceeded that of malaria and that of dengue. A national rabies control program is needed to improve surveillance and access to PEP, and to initiate vaccination campaigns in dogs. PMID:19907631

Skeletal height estimation from regression analysis of sternal lengths in a Northwest Indian population of Chandigarh region: a postmortem study.

PubMed

Singh, Jagmahender; Pathak, R K; Chavali, Krishnadutt H

2011-03-20

Skeletal height estimation from regression analysis of eight sternal lengths in the subjects of Chandigarh zone of Northwest India is the topic of discussion in this study. Analysis of eight sternal lengths (length of manubrium, length of mesosternum, combined length of manubrium and mesosternum, total sternal length and first four intercostals lengths of mesosternum) measured from 252 male and 91 female sternums obtained at postmortems revealed that mean cadaver stature and sternal lengths were more in North Indians and males than the South Indians and females. Except intercostal lengths, all the sternal lengths were positively correlated with stature of the deceased in both sexes (P < 0.001). The multiple regression analysis of sternal lengths was found more useful than the linear regression for stature estimation. Using multivariate regression analysis, the combined length of manubrium and mesosternum in both sexes and the length of manubrium along with 2nd and 3rd intercostal lengths of mesosternum in males were selected as best estimators of stature. Nonetheless, the stature of males can be predicted with SEE of 6.66 (R(2) = 0.16, r = 0.318) from combination of MBL+BL_3+LM+BL_2, and in females from MBL only, it can be estimated with SEE of 6.65 (R(2) = 0.10, r = 0.318), whereas from the multiple regression analysis of pooled data, stature can be known with SEE of 6.97 (R(2) = 0.387, r = 575) from the combination of MBL+LM+BL_2+TSL+BL_3. The R(2) and F-ratio were found to be statistically significant for almost all the variables in both the sexes, except 4th intercostal length in males and 2nd to 4th intercostal lengths in females. The 'major' sternal lengths were more useful than the 'minor' ones for stature estimation The universal regression analysis used by Kanchan et al. [39] when applied to sternal lengths, gave satisfactory estimates of stature for males only but female stature was comparatively better estimated from simple linear regressions. But they are not proposed for the subjects of known sex, as they underestimate the male and overestimate female stature. However, intercostal lengths were found to be the poor estimators of stature (P < 0.05). And also sternal lengths exhibit weaker correlation coefficients and higher standard errors of estimate. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Classifying serial killers.

PubMed

Promish, D I; Lester, D

1999-11-08

We attempted to match the appearance and demeanor of 27 serial killers to the postmortem 'signatures' found on their victims' bodies. Our results suggest that a link may exist between postmortem signatures and two complementary appearance-demeanor types.

Differences between postmortem computed tomography and conventional autopsy in a stabbing murder case

PubMed Central

Zerbini, Talita; da Silva, Luiz Fernando Ferraz; Ferro, Antonio Carlos Gonçalves; Kay, Fernando Uliana; Junior, Edson Amaro; Pasqualucci, Carlos Augusto Gonçalves; do Nascimento Saldiva, Paulo Hilario

2014-01-01

OBJECTIVE: The aim of the present work is to analyze the differences and similarities between the elements of a conventional autopsy and images obtained from postmortem computed tomography in a case of a homicide stab wound. METHOD: Comparison between the findings of different methods: autopsy and postmortem computed tomography. RESULTS: In some aspects, autopsy is still superior to imaging, especially in relation to external examination and the description of lesion vitality. However, the findings of gas embolism, pneumothorax and pulmonary emphysema and the relationship between the internal path of the instrument of aggression and the entry wound are better demonstrated by postmortem computed tomography. CONCLUSIONS: Although multislice computed tomography has greater accuracy than autopsy, we believe that the conventional autopsy method is fundamental for providing evidence in criminal investigations. PMID:25518020

Effects of tea polyphenols on the post-mortem integrity of large yellow croaker (Pseudosciaena crocea) fillet proteins.

PubMed

Zhao, Jin; Lv, Weijin; Wang, Jinlin; Li, Jianrong; Liu, Xiaoxiang; Zhu, Junli

2013-12-01

Tea polyphenols (TP) are known to be important for the post-mortem deterioration of fish muscle and can enhance food quality. To shed light on the influence of TP on the status of large yellow croaker muscle proteins, control and treated fillets (0.1% TP, 0.2% TP and 0.3% TP, w/v) were analysed periodically for myofibrillar protein functional properties (Ca(2+)-ATPase activity, surface hydrophobicity, total sulfhydryl content, emulsion stability index and rheological behaviour). Degradation of the myofibrillar protein myosin could be clearly observed; several proteins were also observed to vary in abundance following post-mortem storage for 25 days. The present study offers new evidence that TP have an effective impact on muscle protein integrity post-mortem. Copyright © 2013 Elsevier Ltd. All rights reserved.

Unusual injury pattern in a case of postmortem animal depredation by a domestic German shepherd.

PubMed

Tsokos, M; Schulz, F; Püschel, K

1999-09-01

A case is presented of a 38-year-old woman with skeletization of the head, neck, and collar region and a circumscribed 26-cm x 19-cm defect on the left chest with sole removal of the heart through the opened pericardium but undamaged mediastinum and lungs. The injuries showed V-shaped puncture wounds and superficial claw-induced scratches adjacent to the wound margins that have been described as typical for postmortem animal depredation of carnivore origin and derived from postmortem animal damage by the woman's domestic German shepherd. The circumscribed destruction of the left chest with unusual opening of the pericardium is explained by the physiognomy of the muzzle of the German shepherd and differs from previous reports. Any case presented as postmortem animal mutilation should be viewed with skepticism and undergo a full autopsy.

[Current macro-diagnostic trends of forensic medicine in the Czech Republic].

PubMed

Frišhons, Jan; Kučerová, Štěpánka; Jurda, Mikoláš; Sokol, Miloš; Vojtíšek, Tomáš; Hejna, Petr

2017-01-01

Over the last few years, advanced diagnostic methods have penetrated in the realm of forensic medicine in addition to standard autopsy techniques supported by traditional X-ray examination and macro-diagnostic laboratory tests. Despite the progress of imaging methods, the conventional autopsy has remained basic and essential diagnostic tool in forensic medicine. Postmortem computed tomography and magnetic resonance imaging are far the most progressive modern radio diagnostic methods setting the current trend of virtual autopsies all over the world. Up to now, only two institutes of forensic medicine have available postmortem computed tomography for routine diagnostic purposes in the Czech Republic. Postmortem magnetic resonance is currently unattainable for routine diagnostic use and was employed only for experimental purposes. Photogrammetry is digital method focused primarily on body surface imaging. Recently, the most fruitful results have been yielded from the interdisciplinary cooperation between forensic medicine and forensic anthropology with the implementation of body scanning techniques and 3D printing. Non-invasive and mini-invasive investigative methods such as postmortem sonography and postmortem endoscopy was unsystematically tested for diagnostic performance with good outcomes despite of limitations of these methods in postmortem application. Other futuristic methods, such as the use of a drone to inspect the crime scene are still experimental tools. The authors of the article present a basic overview of the both routinely and experimentally used investigative methods and current macro-diagnostic trends of the forensic medicine in the Czech Republic.

Effects of postmortem aging and USDA quality grade on Warner-Bratzler shear force values of seventeen individual beef muscles.

PubMed

Gruber, S L; Tatum, J D; Scanga, J A; Chapman, P L; Smith, G C; Belk, K E

2006-12-01

Forty USDA Select and 40 upper two-thirds USDA Choice beef carcasses were used to determine the effects of postmortem aging on tenderness of 17 individual beef muscles. Biceps femoris-long head, complexus, gluteus medius, infraspinatus, longissimus dorsi, psoas major, rectus femoris, semimembranosus, semitendinosus, serratus ventralis, spinalis dorsi, supraspinatus, tensor fasciae latae, teres major, triceps brachii-long head, vastus lateralis, and vastus medialis muscles were removed from each carcass. Seven steaks (2.54-cm thick) were cut from every muscle, and each steak was assigned to one of the following postmortem aging periods: 2, 4, 6, 10, 14, 21, or 28 d postmortem. After completion of the designated aging period, steaks were removed from storage (2 degrees C, never frozen), cooked to a peak internal temperature of 71 degrees C, and evaluated using Warner-Bratzler shear force (WBSF). Analysis of WBSF revealed a 3-way interaction (P = 0.004) among individual muscle, USDA quality grade, and postmortem aging period. With the exception of the Select teres major, WBSF of all muscles (both quality grades) decreased with increasing time of postmortem storage. Nonlinear regression was used to characterize the extent (aging response) and rate of decrease in WBSF from 2 through 28 d postmortem for each muscle within each quality grade. In general, WBSF of upper two-thirds Choice muscles decreased more rapidly from 2 to 10 d postmortem than did corresponding Select muscles. Muscles that had greater aging responses generally had greater 2-d WBSF values. The upper two-thirds Choice psoas major, serratus ventralis, and vastus lateralis muscles required similar aging times to complete a majority of the aging response (< or =0.1 kg of aging response remaining) compared with analogous Select muscles. The upper two-thirds Choice complexus, gluteus medius, semitendinosus, triceps brachii-long head, and vastus medialis muscles required 4 to 6 d less time to complete a majority of the aging response than did comparable Select muscles. Aging times for Select biceps femoris-long head, infraspinatus, longissimus dorsi, rectus femoris, semimembranosus, spinalis dorsi, supraspinatus, and tensor fasciae latae muscles were > or =7 d longer than those for corresponding upper two-thirds Choice muscles. Results from this study suggest that muscle-to-muscle tenderness differences depend on quality grade and aging time and that postmortem aging should be managed with respect to individual muscle and USDA quality grade.

Technical note: validation of a model for online classification of US Select beef carcasses for longissimus tenderness using visible and near-infrared reflectance spectroscopy.

PubMed

Shackelford, S D; Wheeler, T L; Koohmaraie, M

2012-03-01

The present experiment was conducted to provide a validation of a previously developed model for online classification of US Select carcasses for LM tenderness based on visible and near-infrared (VISNIR) spectroscopy and to determine if the accuracy of VISNIR-based tenderness classification could be enhanced by making measurements after postmortem aging. Spectroscopy was conducted online, during carcass grading, at a large-scale commercial fed beef-processing facility, and the strip loin was obtained from the left side of US Select carcasses (n = 467). Slice shear force (SSF) was measured on fresh steaks at 2 and 14 d postmortem. Online VISNIR tenderness classes differed in mean SSF values at both 2 d (29.4 vs. 33.6 kg) and 14 d (18.0 vs. 21.2 kg) postmortem (P < 10(-7)). Online VISNIR tenderness classes differed in both the percentage of carcasses with LM SSF values greater than 40 kg at 2 d postmortem (5.1 vs. 21.0%; P < 10(-6)) and the percentage of carcasses with LM SSF values greater than 25 kg at 14 d postmortem (6.8 vs. 23.2%; P < 10(-5)). Whereas 15.0% of the carcasses sampled for this experiment had LM SSF values greater than 25 kg at 14 d postmortem, only 6.8% of the carcasses classified as tender by VISNIR had LM SSF values greater than 25 kg. All the carcasses sampled that had LM SSF values greater than 35 kg at 14 d postmortem were accurately classified as tough by VISNIR. Before measurement of SSF on d 14, VISNIR spectroscopy was conducted on the SSF steak. Tenderness classes based on d 14 VISNIR spectra differed both in mean SSF value at 14 d postmortem (17.7 vs. 21.6 kg; P < 10(-11)) and the percentage of carcasses with LM SSF values greater than 25 kg at 14 d postmortem (7.3 vs. 22.7%; P < 10(-5)). These data support our previous work showing that VISNIR spectroscopy can be used to classify US Select carcasses noninvasively for LM tenderness, and the results establish that this technology could also be applied to aged US Select strip loins. This technology would allow packing companies and other segments of the beef marketing chain to identify US Select carcasses or strip loins that excel in LM tenderness for use in branded beef programs.

Postmortem distribution of guaifenesin concentrations reveals a lack of potential for redistribution.

PubMed

McIntyre, Iain M; Navarrete, Aylmer; Mena, Othon

2014-12-01

Therapeutic (or non-toxic) postmortem guaifenesin blood and liver concentrations have not been previously described. Peripheral blood guaifenesin concentrations were compared to central blood and liver concentrations in eight medical examiner cases. Specimens were initially screened for alcohol and simple volatiles, drugs of abuse, alkaline, and acid/neutral drugs. Guaifenesin, when detected by the acid/neutral drug screen, was subsequently confirmed and quantified by a high performance liquid chromatography procedure. Data suggest that postmortem guaifenesin peripheral blood concentrations may be considered non-toxic to at least 5.4mg/L with liver concentrations to at least 7.0mg/kg. Overall, guaifenesin concentrations ranged from 1.9 to 40mg/L in peripheral blood, 2.2-150mg/L in central blood, and 2.6-36mg/kg in liver. The median guaifenesin central blood to peripheral blood ratio was 1.1 (N=8). Similarly, liver to peripheral blood ratios showed a median value of 0.9L/kg (N=5). Given that a liver to peripheral blood ratio less than 5L/kg is consistent with little to no propensity for postmortem redistribution, these data suggest that guaifenesin is not prone to substantial postmortem redistribution. Published by Elsevier Ireland Ltd.

Microglial dystrophy in the aged and Alzheimer's disease brain is associated with ferritin immunoreactivity.

PubMed

Lopes, Kryslaine O; Sparks, D Larry; Streit, Wolfgang J

2008-08-01

Degeneration of microglial cells may be important for understanding the pathogenesis of aging-related neurodegeneration and neurodegenerative diseases. In this study, we analyzed the morphological characteristics of microglial cells in the nondemented and Alzheimer's disease (AD) human brain using ferritin immunohistochemistry. The central hypothesis was that expression of the iron storage protein ferritin increases the susceptibility of microglia to degeneration, particularly in the aged brain since senescent microglia might become less efficient in maintaining iron homeostasis and free iron can promote oxidative damage. In a primary set of 24 subjects (age range 34-97 years) examined, microglial cells immunoreactive for ferritin were found to constitute a subpopulation of the larger microglial pool labeled with an antibody for HLA-DR antigens. The majority of these ferritin-positive microglia exhibited aberrant morphological (dystrophic) changes in the aged and particularly in the AD brain. No spatial correlation was found between ferritin-positive dystrophic microglia and senile plaques in AD tissues. Analysis of a secondary set of human postmortem brain tissues with a wide range of postmortem intervals (PMI, average 10.94 +/- 5.69 h) showed that the occurrence of microglial dystrophy was independent of PMI and consequently not a product of tissue autolysis. Collectively, these results suggest that microglial involvement in iron storage and metabolism contributes to their degeneration, possibly through increased exposure of the cells to oxidative stress. We conclude that ferritin immunohistochemistry may be a useful method for detecting degenerating microglia in the human brain. (c) 2008 Wiley-Liss, Inc.

Isoproterenol reduces ischemia-reperfusion lung injury despite beta-blockade.

PubMed

Takashima, Seiki; Schlidt, Scott A; Koukoulis, Giovanna; Sevala, Mayura; Egan, Thomas M

2005-06-01

If lungs could be retrieved from non-heart-beating donors (NHBDs), the shortage of lungs for transplantation could be alleviated. The use of lungs from NHBDs is associated with a mandatory warm ischemic interval, which results in ischemia-reperfusion injury upon reperfusion. In an earlier study, rat lungs retrieved 2-h postmortem from NHBDs had reduced capillary leak measured by filtration coefficient (Kfc) when reperfused with isoproterenol (iso), associated with an increase in lung tissue levels of cyclic AMP (cAMP). The objective was to determine if this decrease in Kfc was because of beta-stimulation, or would persist despite beta-blockade. Donor rats were treated intraperitoneally with beta-blockade (propranolol or pindolol) or carrier, sacrificed, and lungs were retrieved immediately or 2 h postmortem. The lungs were reperfused with or without iso and the beta-blockers in the reperfusate. Outcome measures were Kfc, wet:dry weight ratio (W/D), lung levels of adenine nucleotides and cAMP. Lungs retrieved immediately after death had normal Kfc and W/D. After 2 h of ischemia, Kfc and W/D were markedly elevated in controls (no drug) and lungs reperfused with beta-blockers alone. Isoproterenol-reperfusion decreased Kfc and W/D significantly (P < 0.01) even in the presence of beta-blockade. Lung cAMP levels were increased only with iso in the absence of beta-blockade. The attenuation of ischemia-reperfusion injury because of iso occurs even in the presence of beta-blockade, and may not be a result of beta-stimulated increased cAMP.

14. VIEW IN THE WEST OPERATING GALLERY OF POSTMORTEM CELL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. VIEW IN THE WEST OPERATING GALLERY OF POST-MORTEM CELL WORK STATION AND MANIPULATOR ARMS. - Nevada Test Site, Engine Maintenance Assembly & Disassembly Facility, Area 25, Jackass Flats, Mercury, Nye County, NV

Distribution of Delta 9-Tetrahydrocannabinol and 11-Nor-9-Carboxy-Delta 9-Tetrahydrocannabinol Acid in Postmortem Biological Fluids and Tissues From Pilots Fatally Injured in Aviation Accidents

DTIC Science & Technology

2013-12-01

classified as current marijuana ( Cannabis sativa) users in the United States and 5.4 million people aged 12 and older used marijuana on a daily or almost...report from the European Union, cannabis use is common in many parts of the world.3 As a result of such widespread marijuana use and its well...knowledge regarding the postmortem distribution of cannabi - noids in humans primarily because cannabinoid testing is not routine in many postmortem

Weighted regression analysis and interval estimators

Treesearch

Donald W. Seegrist

1974-01-01

A method for deriving the weighted least squares estimators for the parameters of a multiple regression model. Confidence intervals for expected values, and prediction intervals for the means of future samples are given.

Sample size planning for composite reliability coefficients: accuracy in parameter estimation via narrow confidence intervals.

PubMed

Terry, Leann; Kelley, Ken

2012-11-01

Composite measures play an important role in psychology and related disciplines. Composite measures almost always have error. Correspondingly, it is important to understand the reliability of the scores from any particular composite measure. However, the point estimates of the reliability of composite measures are fallible and thus all such point estimates should be accompanied by a confidence interval. When confidence intervals are wide, there is much uncertainty in the population value of the reliability coefficient. Given the importance of reporting confidence intervals for estimates of reliability, coupled with the undesirability of wide confidence intervals, we develop methods that allow researchers to plan sample size in order to obtain narrow confidence intervals for population reliability coefficients. We first discuss composite reliability coefficients and then provide a discussion on confidence interval formation for the corresponding population value. Using the accuracy in parameter estimation approach, we develop two methods to obtain accurate estimates of reliability by planning sample size. The first method provides a way to plan sample size so that the expected confidence interval width for the population reliability coefficient is sufficiently narrow. The second method ensures that the confidence interval width will be sufficiently narrow with some desired degree of assurance (e.g., 99% assurance that the 95% confidence interval for the population reliability coefficient will be less than W units wide). The effectiveness of our methods was verified with Monte Carlo simulation studies. We demonstrate how to easily implement the methods with easy-to-use and freely available software. ©2011 The British Psychological Society.

Relationship between clinical signs and postmortem test status in cattle experimentally infected with the bovine spongiform encephalopathy agent

PubMed Central

2010-01-01

Background Various clinical protocols have been developed to aid in the clinical diagnosis of classical bovine spongiform encephalopathy (BSE), which is confirmed by postmortem examinations based on vacuolation and accumulation of disease-associated prion protein (PrPd) in the brain. The present study investigated the occurrence and progression of sixty selected clinical signs and behaviour combinations in 513 experimentally exposed cattle subsequently categorised postmortem as confirmed or unconfirmed BSE cases. Appropriate undosed or saline inoculated controls were examined similarly and the data analysed to explore the possible occurrence of BSE-specific clinical expression in animals unconfirmed by postmortem examinations. Results Based on the display of selected behavioural, sensory and locomotor changes, 20 (67%) orally dosed and 17 (77%) intracerebrally inoculated pathologically confirmed BSE cases and 21 (13%) orally dosed and 18 (6%) intracerebrally inoculated but unconfirmed cases were considered clinical BSE suspects. None of 103 controls showed significant signs and were all negative on diagnostic postmortem examinations. Signs indicative of BSE suspects, particularly over-reactivity and ataxia, were more frequently displayed in confirmed cases with vacuolar changes in the brain. The display of several BSE-associated signs over time, including repeated startle responses and nervousness, was significantly more frequent in confirmed BSE cases compared to controls, but these two signs were also significantly more frequent in orally dosed cattle unconfirmed by postmortem examinations. Conclusions The findings confirm that in experimentally infected cattle clinical abnormalities indicative of BSE are accompanied by vacuolar changes and PrPd accumulation in the brainstem. The presence of more frequently expressed signs in cases with vacuolar changes is consistent with this pathology representing a more advanced stage of disease. That BSE-like signs or sign combinations occur in inoculated animals that were not confirmed as BSE cases by postmortem examinations requires further study to investigate the potential causal relationship with prion disease. PMID:21143919

Venous air embolism: An under-recognised entity in blunt-force trauma and the importance of radiology.

PubMed

du Plessis, Marna; du Toit-Prinsloo, Lorraine

2017-04-01

Air embolism (AE) is considered a rare event and can be either iatrogenic or traumatic. Various post-mortem methods to detect AE exist, of which radiology is preferred. The presence of air in the heart can be demonstrated using special dissection techniques where the heart is opened under water or by needle puncture from a water-filled syringe. Three cases of blunt-force head injury are presented herein, with AE being diagnosed by conventional radiography using a Lodox Statscan® full-body digital X-ray machine in all cases. This case series demonstrates that AE due to blunt-force trauma to the head and sinuses might be under-recognised in the forensic post-mortem setting. It also highlights the importance of radiology in diagnosing AE post-mortem, especially where the results of post-mortem techniques might be unsatisfactory.

Storm-Related Postmortem Damage to Skeletal Remains.

PubMed

Maijanen, Heli; Wilson-Taylor, Rebecca J; Jantz, Lee Meadows

2016-05-01

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. © 2016 American Academy of Forensic Sciences.

[The expressions of HSP 70 mRNA and c-fos mRNA in the skeletal muscle and cardiac muscle of rabbits by electrocuted].

PubMed

Wang, Ye; Liu, Min; Cheng, Wei-bo; He, Gui-qiong; Li, Fan; Liao, Zhi-gang

2008-08-01

To study the changes of HSP 70 mRNA and c-fos mRNA expression and to find a method to differentiate antemortem from postmortem electrocution. Fifteen New Zealand rabbits were randomly divided into three groups, the antemortem electrocution group, the postmortem electrocution group, and the control group. Each group consists of five rabbits. The levels of HSP 70 mRNA and c-fos mRNA in skeletal muscle and cardiac muscle were examined with quantitative fluorescent RT-PCR. The levels of HSP 70 mRNA and c-fos mRNA in the antemortem electrocution group increased significantly (P<0.05), compared with that of the postmortem electrocution group. The changes of HSP 70 mRNA and c-fos mRNA expression in skeletal muscle and cardiac muscle can be used as an indicator to distinguish antemortem from postmortem electrocution.

Maximum likelihood estimates, from censored data, for mixed-Weibull distributions

NASA Astrophysics Data System (ADS)

Jiang, Siyuan; Kececioglu, Dimitri

1992-06-01

A new algorithm for estimating the parameters of mixed-Weibull distributions from censored data is presented. The algorithm follows the principle of maximum likelihood estimate (MLE) through the expectation and maximization (EM) algorithm, and it is derived for both postmortem and nonpostmortem time-to-failure data. It is concluded that the concept of the EM algorithm is easy to understand and apply (only elementary statistics and calculus are required). The log-likelihood function cannot decrease after an EM sequence; this important feature was observed in all of the numerical calculations. The MLEs of the nonpostmortem data were obtained successfully for mixed-Weibull distributions with up to 14 parameters in a 5-subpopulation, mixed-Weibull distribution. Numerical examples indicate that some of the log-likelihood functions of the mixed-Weibull distributions have multiple local maxima; therefore, the algorithm should start at several initial guesses of the parameter set.

Dead in the water--are we killing the hospital autopsy with poor consent practices?

PubMed

Henry, Jaimie; Nicholas, Nick

2012-07-01

It is now a recognized fact that the practice of conducting a consent (or hospital) post-mortem examination is in decline. There have been many reasons put forth to explain this demise, but the quality of the consenting process is frequently cited as having a high impact. This article focuses on consent practices for post-mortem examinations in England and Wales, and considers if our consent techniques are adversely affecting post-mortem examination uptake. We examine the regulatory compliance of trusts with their statutory obligations by analyzing the Human Tissue Authority's compliance and inspection reports. We further analyze 21 publicly available NHS Trust policies on post-mortem examination consent procedures, and consider whether these are fit for the purpose of meeting the dual needs of clinicians and the bereaved. Despite more Human Tissue Authority inspections, there is a disproportionate rise in enforcement actions, with up to 48% of sampled Trusts exhibiting shortcomings in their legal duties. Additionally, only 52.4% of sampled trusts follow the Human Tissue Authority best-practice model, with 23.8% having no documented procedures. Despite the well founded evidence base for best-practice models, consent practices for post-mortem examinations remains poor and is likely to have a gross adverse effect on the rate of post-mortem examinations. We recommend that NHS Trusts rigorously review their protocols and introduce a team-approach between clinicians and trained bereavement staff in core-consent teams, as the Human Tissue Authority suggests, whilst at the same time placing a strong emphasis on education for junior and senior colleagues alike.

Effect of animal mixing as a stressor on biomarkers of autophagy and oxidative stress during pig muscle maturation.

PubMed

Rubio-González, A; Potes, Y; Illán-Rodríguez, D; Vega-Naredo, I; Sierra, V; Caballero, B; Fàbrega, E; Velarde, A; Dalmau, A; Oliván, M; Coto-Montes, A

2015-07-01

The objective of this work was to study the postmortem evolution of potential biomarkers of autophagy (Beclin 1, LC3-II/LC3-I ratio) and oxidative stress (total antioxidant activity, TAA; superoxide dismutase activity, SOD and catalase activity, CAT) in the Longissimus dorsi muscle of entire male ((Large White×Landrace)×Duroc) pigs subjected to different management treatments that may promote stress, such as mixing unfamiliar animals at the farm and/or during transport and lairage before slaughter. During the rearing period at the farm, five animals were never mixed after the initial formation of the experimental groups (unmixed group at the farm, UF), whereas 10 animals were subjected to a common routine of being mixed with unfamiliar animals (mixed group at the farm, MF). Furthermore, two different treatments were used during the transport and lairage before slaughter: 10 pigs were not mixed (unmixed group during transport and lairage, UTL), whereas five pigs were mixed with unfamiliar animals on the lorry and during lairage (mixed group during transport and lairage, MTL). These mixing treatments were then combined into three pre-slaughter treatments - namely, UF-UTL, MF-UTL and MF-MTL. The results show that MF-UTL and MF-MTL increased significantly the muscle antioxidant defense (TAA, SOD and CAT) at short postmortem times (4 and 8 h; P<0.001), followed by an earlier depletion of the antioxidant activity at 24 h postmortem (P<0.05). We also found that mixing unfamiliar animals, both at the farm and during transport and lairage, triggers postmortem muscle autophagy, which showed an earlier activation (higher expression of Beclin 1 and LC3-II/LC3-I ratio at 4 h postmortem followed by a decreasing pattern of this ratio along first 24 h postmortem) in the muscle tissues of animals from the MF-UTL and MF-MTL groups, as an adaptive strategy of the muscle cells for counteracting induced stress. From these results, we propose that monitoring the evolution of the main biomarkers of autophagy (Beclin 1, LC3-II/LC3-I ratio) and muscle antioxidant defense (TAA, SOD, CAT) in the muscle tissue within the first 24 h postmortem may help the detection of animal stress and its potential effect on the postmortem muscle metabolism.

Cross-cultural estimation of the human generation interval for use in genetics-based population divergence studies.

PubMed

Fenner, Jack N

2005-10-01

The length of the human generation interval is a key parameter when using genetics to date population divergence events. However, no consensus exists regarding the generation interval length, and a wide variety of interval lengths have been used in recent studies. This makes comparison between studies difficult, and questions the accuracy of divergence date estimations. Recent genealogy-based research suggests that the male generation interval is substantially longer than the female interval, and that both are greater than the values commonly used in genetics studies. This study evaluates each of these hypotheses in a broader cross-cultural context, using data from both nation states and recent hunter-gatherer societies. Both hypotheses are supported by this study; therefore, revised estimates of male, female, and overall human generation interval lengths are proposed. The nearly universal, cross-cultural nature of the evidence justifies using these proposed estimates in Y-chromosomal, mitochondrial, and autosomal DNA-based population divergence studies.

Dating human skeletal remains using a radiometric method: biogenic versus diagenetic 90Sr and 210Pb in vertebrae.

PubMed

Schrag, Bettina; Uldin, Tanya; Mangin, Patrice; Froidevaux, Pascal

2012-07-10

In forensic science, there is a strong interest in determining the post-mortem interval (PMI) of human skeletal remains up to 50 years after death. Currently, there are no reliable methods to resolve PMI, the determination of which relies almost exclusively on the experience of the investigating expert. Here we measured (90)Sr and (210)Pb ((210)Po) incorporated into bones through a biogenic process as indicators of the time elapsed since death. We hypothesised that the activity of radionuclides incorporated into trabecular bone will more accurately match the activity in the environment and the food chain at the time of death than the activity in cortical bone because of a higher remodelling rate. We found that determining (90)Sr can yield reliable PMI estimates as long as a calibration curve exists for (90)Sr covering the studied area and the last 50 years. We also found that adding the activity of (210)Po, a proxy for naturally occurring (210)Pb incorporated through ingestion, to the (90)Sr dating increases the reliability of the PMI value. Our results also show that trabecular bone is subject to both (90)Sr and (210)Po diagenesis. Accordingly, we used a solubility profile method to determine the biogenic radionuclide only, and we are proposing a new method of bone decontamination to be used prior to (90)Sr and (210)Pb dating. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Assessing Interval Estimation Methods for Hill Model ...

EPA Pesticide Factsheets

The Hill model of concentration-response is ubiquitous in toxicology, perhaps because its parameters directly relate to biologically significant metrics of toxicity such as efficacy and potency. Point estimates of these parameters obtained through least squares regression or maximum likelihood are commonly used in high-throughput risk assessment, but such estimates typically fail to include reliable information concerning confidence in (or precision of) the estimates. To address this issue, we examined methods for assessing uncertainty in Hill model parameter estimates derived from concentration-response data. In particular, using a sample of ToxCast concentration-response data sets, we applied four methods for obtaining interval estimates that are based on asymptotic theory, bootstrapping (two varieties), and Bayesian parameter estimation, and then compared the results. These interval estimation methods generally did not agree, so we devised a simulation study to assess their relative performance. We generated simulated data by constructing four statistical error models capable of producing concentration-response data sets comparable to those observed in ToxCast. We then applied the four interval estimation methods to the simulated data and compared the actual coverage of the interval estimates to the nominal coverage (e.g., 95%) in order to quantify performance of each of the methods in a variety of cases (i.e., different values of the true Hill model paramet

Forensic postmortem computed tomography: volumetric measurement of the heart and liver.

PubMed

Jakobsen, Lykke Schrøder; Lundemose, Sissel; Banner, Jytte; Lynnerup, Niels; Jacobsen, Christina

2016-12-01

The purpose of this study was to investigate the utility of postmortem computed tomography (PMCT) images in estimating organ sizes and to examine the use of the cardiothoracic ratio (CTR). We included 45 individuals (19 females), who underwent a medico-legal autopsy. Using the computer software program Mimics ® , we determined in situ heart and liver volumes derived from linear measurements (width, height and depth) on a whole body PMCT-scan, and compared the volumes with ex vivo volumes derived by CT-scan of the eviscerated heart and liver. The ex vivo volumes were also compared with the organ weights. Further, we compared the CTR with the ex vivo heart volume and a heart weight-ratio (HWR). Intra- and inter-observer analyses were performed. We found no correlation between the in situ and ex vivo volumes of the heart and liver. However, a highly significant correlation was found between the ex vivo volumes and weights of the heart and liver. No correlations between CTR and the ex vivo heart volume nor with HWR was found. Concerning cardiomegaly, we found no agreement between the CTR and HWR. The intra- and inter-observer analyses showed no significant differences. Noninvasive in situ PMCT methods for organ measuring, as performed in this study, are not useful tools in forensic pathology. The best method to estimate organ volume is a CT-scan of the eviscerated organ. PMCT-determined CTR seems to be useless for ascertaining cardiomegaly, as it neither correlated with the ex vivo heart volume nor with the HWR.

Neuropathology of White Matter Lesions, Blood-Brain Barrier Dysfunction, and Dementia.

PubMed

Hainsworth, Atticus H; Minett, Thais; Andoh, Joycelyn; Forster, Gillian; Bhide, Ishaan; Barrick, Thomas R; Elderfield, Kay; Jeevahan, Jamuna; Markus, Hugh S; Bridges, Leslie R

2017-10-01

We tested whether blood-brain barrier dysfunction in subcortical white matter is associated with white matter abnormalities or risk of clinical dementia in older people (n=126; mean age 86.4, SD: 7.7 years) in the MRC CFAS (Medical Research Council Cognitive Function and Ageing Study). Using digital pathology, we quantified blood-brain barrier dysfunction (defined by immunohistochemical labeling for the plasma marker fibrinogen). This was assessed within subcortical white matter tissue samples harvested from postmortem T 2 magnetic resonance imaging (MRI)-detected white matter hyperintensities, from normal-appearing white matter (distant from coexistent MRI-defined hyperintensities), and from equivalent areas in MRI normal brains. Histopathologic lesions were defined using a marker for phagocytic microglia (CD68, clone PGM1). Extent of fibrinogen labeling was not significantly associated with white matter abnormalities defined either by MRI (odds ratio, 0.90; 95% confidence interval, 0.79-1.03; P =0.130) or by histopathology (odds ratio, 0.93; 95% confidence interval, 0.77-1.12; P =0.452). Among participants with normal MRI (no detectable white matter hyperintensities), increased fibrinogen was significantly related to decreased risk of clinical dementia (odds ratio, 0.74; 95% confidence interval, 0.58-0.94; P =0.013). Among participants with histological lesions, increased fibrinogen was related to increased risk of dementia (odds ratio, 2.26; 95% confidence interval, 1.25-4.08; P =0.007). Our data suggest that some degree of blood-brain barrier dysfunction is common in older people and that this may be related to clinical dementia risk, additional to standard MRI biomarkers. © 2017 American Heart Association, Inc.

Circuit- and Diagnosis-Specific DNA Methylation Changes at γ-Aminobutyric Acid-Related Genes in Postmortem Human Hippocampus in Schizophrenia and Bipolar Disorder.

PubMed

Ruzicka, W Brad; Subburaju, Sivan; Benes, Francine M

2015-06-01

Dysfunction related to γ-aminobutyric acid (GABA)-ergic neurotransmission in the pathophysiology of major psychosis has been well established by the work of multiple groups across several decades, including the widely replicated downregulation of GAD1. Prior gene expression and network analyses within the human hippocampus implicate a broader network of genes, termed the GAD1 regulatory network, in regulation of GAD1 expression. Several genes within this GAD1 regulatory network show diagnosis- and sector-specific expression changes within the circuitry of the hippocampus, influencing abnormal GAD1 expression in schizophrenia and bipolar disorder. To investigate the hypothesis that aberrant DNA methylation contributes to circuit- and diagnosis-specific abnormal expression of GAD1 regulatory network genes in psychotic illness. This epigenetic association study targeting GAD1 regulatory network genes was conducted between July 1, 2012, and June 30, 2014. Postmortem human hippocampus tissue samples were obtained from 8 patients with schizophrenia, 8 patients with bipolar disorder, and 8 healthy control participants matched for age, sex, postmortem interval, and other potential confounds from the Harvard Brain Tissue Resource Center, McLean Hospital, Belmont, Massachusetts. We extracted DNA from laser-microdissected stratum oriens tissue of cornu ammonis 2/3 (CA2/3) and CA1 postmortem human hippocampus, bisulfite modified it, and assessed it with the Infinium HumanMethylation450 BeadChip (Illumina, Inc). The subset of CpG loci associated with GAD1 regulatory network genes was analyzed in R version 3.1.0 software (R Foundation) using the minfi package. Findings were validated using bisulfite pyrosequencing. Methylation levels at 1308 GAD1 regulatory network-associated CpG loci were assessed both as individual sites to identify differentially methylated positions and by sharing information among colocalized probes to identify differentially methylated regions. A total of 146 differentially methylated positions with a false detection rate lower than 0.05 were identified across all 6 groups (2 circuit locations in each of 3 diagnostic categories), and 54 differentially methylated regions with P < .01 were identified in single-group comparisons. Methylation changes were enriched in MSX1, CCND2, and DAXX at specific loci within the hippocampus of patients with schizophrenia and bipolar disorder. This work demonstrates diagnosis- and circuit-specific DNA methylation changes at a subset of GAD1 regulatory network genes in the human hippocampus in schizophrenia and bipolar disorder. These genes participate in chromatin regulation and cell cycle control, supporting the concept that the established GABAergic dysfunction in these disorders is related to disruption of GABAergic interneuron physiology at specific circuit locations within the human hippocampus.

Circuit- and Diagnosis-Specific DNA Methylation Changes at γ-Aminobutyric Acid–Related Genes in Postmortem Human Hippocampus in Schizophrenia and Bipolar Disorder

PubMed Central

Ruzicka, W. Brad; Subburaju, Sivan; Benes, Francine M.

2017-01-01

IMPORTANCE Dysfunction related to γ-aminobutyric acid (GABA)–ergic neurotransmission in the pathophysiology of major psychosis has been well established by the work of multiple groups across several decades, including the widely replicated downregulation of GAD1. Prior gene expression and network analyses within the human hippocampus implicate a broader network of genes, termed the GAD1 regulatory network, in regulation of GAD1 expression. Several genes within this GAD1 regulatory network show diagnosis- and sector-specific expression changes within the circuitry of the hippocampus, influencing abnormal GAD1 expression in schizophrenia and bipolar disorder. OBJECTIVE To investigate the hypothesis that aberrant DNA methylation contributes to circuit- and diagnosis-specific abnormal expression of GAD1 regulatory network genes in psychotic illness. DESIGN, SETTING, AND PARTICIPANTS This epigenetic association study targeting GAD1 regulatory network genes was conducted between July 1, 2012, and June 30, 2014. Postmortem human hippocampus tissue samples were obtained from 8patients with schizophrenia, 8 patients with bipolar disorder, and 8 healthy control participants matched for age, sex, postmortem interval, and other potential confounds from the Harvard Brain Tissue Resource Center, McLean Hospital, Belmont,Massachusetts. We extracted DNA from laser-microdissected stratum oriens tissue of cornu ammonis 2/3 (CA2/3) and CA1 postmortem human hippocampus, bisulfite modified it, and assessed it with the Infinium HumanMethylation450 BeadChip (Illumina, Inc). The subset of CpG loci associated with GAD1 regulatory network genes was analyzed in R version 3.1.0 software (R Foundation) using the minfi package. Findings were validated using bisulfite pyrosequencing. MAIN OUTCOMES AND MEASURES Methylation levels at 1308 GAD1 regulatory network–associated CpG loci were assessed both as individual sites to identify differentially methylated positions and by sharing information among colocalized probes to identify differentially methylated regions. RESULTS A total of 146 differentially methylated positions with a false detection rate lower than 0.05 were identified across all 6 groups (2 circuit locations in each of 3 diagnostic categories), and 54 differentially methylated regions with P < .01 were identified in single-group comparisons. Methylation changes were enriched in MSX1, CCND2, and DAXX at specific loci within the hippocampus of patients with schizophrenia and bipolar disorder. CONCLUSIONS AND RELEVANCE This work demonstrates diagnosis- and circuit-specific DNA methylation changes at a subset of GAD1 regulatory network genes in the human hippocampus in schizophrenia and bipolar disorder. These genes participate in chromatin regulation and cell cycle control, supporting the concept that the established GABAergic dysfunction in these disorders is related to disruption of GABAergic interneuron physiology at specific circuit locations within the human hippocampus. PMID:25738424

Pilot-Reported Beta-Blockers Identified by Forensic Toxicology Analysis of Postmortem Specimens

DOT National Transportation Integrated Search

2017-01-01

This study compared beta-blockers reported by pilots with the medications found by postmortem toxicology analysis of specimens received from fatal aviation accidents between 1999 and 2015. Several studies have compared drugs using the standard approa...

Post-mortem diagnosis of chronic Chagas's disease comparative evaluation of three serological tests on pericardial fluid.

PubMed

Lopes, E R; Chapadeiro, E; Batista, S M; Cunha, J G; Rocha, A; Miziara, L; Ribeiro, J U; Patto, R J

1978-01-01

In an attempt to improve the post-mortem diagnosis of Chagas's disease the authors performed haemagglutination tests (HAT), fluorescent Trypanosoma cruzi antibody tests (FAT), and complement fixation tests (CFT) on the pericardial fluid obtained at autopsy of 50 individuals with Chagas's heart disease, and 93 patients in whom this disease was not thought to be present. The results demonstrate that all three tests are efficient for the post-mortem diagnosis of Chagas's disease but suggest that their combined use would detect more cases than would one isolated reaction only.

Principles and procedures in forensic toxicology.

PubMed

Wyman, John F

2012-09-01

The principles and procedures employed in a modern forensic toxicology lab are detailed in this review. Aspects of Behavioral and Postmortem toxicology, including certification of analysts and accreditation of labs, chain of custody requirements, typical testing services provided, rationale for specimen selection, and principles of quality assurance are discussed. Interpretation of toxicology results in postmortem specimens requires the toxicologist and pathologist to be cognizant of drug-drug interactions, drug polymorphisms and pharmacogenomics, the gross signs of toxic pathology, postmortem redistribution, confirmation of systemic toxicity in suspected overdoses, the possibility of developed tolerance, and the effects of decomposition on drug concentration.

[Methodology of determination of the time of death and outlooks for the further development].

PubMed

Novikov, P I; Vlasov, A Iu; Shved, E F; Natsentov, E O; Korshunov, N V; Belykh, S A

2004-01-01

A methodological analysis of diagnosing the prescription of death coming (PDC) is described in the paper. Key philosophic fundamentals for further novel and more effective methods of PDC determination are elucidated. Main requirement applicable to postmortem diagnosis are defined. Different methods of modeling the postmortem process are demonstrated by the example of cadaver cooling, i.e. in real time, by analogue computer systems and by mathematic modeling. The traditional empiric and the adaptive approaches are comparatively analyzed in modeling the postmortem processes for the PDC diagnosis. A variety of promising trends for further related research is outlined.

Postmortem dynamic cerebral angiography for detecting aneurysm and bleeding sites in cases of subarachnoid hemorrhage.

PubMed

Inokuchi, Go; Yajima, Daisuke; Hayakawa, Mutsumi; Motomura, Ayumi; Chiba, Fumiko; Torimitsu, Suguru; Makino, Yohsuke; Iwase, Hirotaro

2014-12-01

One of the advantages of postmortem imaging is its ability to obtain diagnostic findings in a non-destructive manner when autopsy is either difficult or may destroy forensic evidence. In recent years, efforts have been made to incorporate computed tomography (CT) based postmortem angiography into forensic pathology; however, it is not currently clear how well the modality can determine sites of bleeding in cases of subarachnoid hemorrhage. Therefore, in this study, we investigated the utility of postmortem cerebral angiography using multi-detector row CT (MDCT) by injecting a contrast medium through a catheter inserted into the internal carotid and vertebral arteries of 10 subarachnoid hemorrhage cases. While postmortem MDCT angiography (PMCTA) was capable of detecting aneurysms in a non-destructive manner, it was sometimes difficult to identify the aneurysm and bleeding sites because of a large amount of contrast medium leaking into the extravascular space. To overcome this problem, we developed the novel contrast imaging method "dynamic cerebral angiography," which involves scanning the same area multiple times while injecting contrast medium to enable real-time observation of the contrasted vasculature. Using multiphase contrast images acquired by this method, we successfully captured the moment when contrast medium leaked from the hemorrhage site. This method will be useful for identifying exact bleeding sites on PMCTA.

Reference interval estimation: Methodological comparison using extensive simulations and empirical data.

PubMed

Daly, Caitlin H; Higgins, Victoria; Adeli, Khosrow; Grey, Vijay L; Hamid, Jemila S

2017-12-01

To statistically compare and evaluate commonly used methods of estimating reference intervals and to determine which method is best based on characteristics of the distribution of various data sets. Three approaches for estimating reference intervals, i.e. parametric, non-parametric, and robust, were compared with simulated Gaussian and non-Gaussian data. The hierarchy of the performances of each method was examined based on bias and measures of precision. The findings of the simulation study were illustrated through real data sets. In all Gaussian scenarios, the parametric approach provided the least biased and most precise estimates. In non-Gaussian scenarios, no single method provided the least biased and most precise estimates for both limits of a reference interval across all sample sizes, although the non-parametric approach performed the best for most scenarios. The hierarchy of the performances of the three methods was only impacted by sample size and skewness. Differences between reference interval estimates established by the three methods were inflated by variability. Whenever possible, laboratories should attempt to transform data to a Gaussian distribution and use the parametric approach to obtain the most optimal reference intervals. When this is not possible, laboratories should consider sample size and skewness as factors in their choice of reference interval estimation method. The consequences of false positives or false negatives may also serve as factors in this decision. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

13. VIEW OF EAST OPERATING GALLERY ALONG THE POSTMORTEM CELLS. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. VIEW OF EAST OPERATING GALLERY ALONG THE POST-MORTEM CELLS. A NUMBER OF MANIPULATOR ARMS COVERED WITH PLASTIC ARE ON THE LEFT WALL. - Nevada Test Site, Engine Maintenance Assembly & Disassembly Facility, Area 25, Jackass Flats, Mercury, Nye County, NV

Machine learning approaches for estimation of prediction interval for the model output.

PubMed

Shrestha, Durga L; Solomatine, Dimitri P

2006-03-01

A novel method for estimating prediction uncertainty using machine learning techniques is presented. Uncertainty is expressed in the form of the two quantiles (constituting the prediction interval) of the underlying distribution of prediction errors. The idea is to partition the input space into different zones or clusters having similar model errors using fuzzy c-means clustering. The prediction interval is constructed for each cluster on the basis of empirical distributions of the errors associated with all instances belonging to the cluster under consideration and propagated from each cluster to the examples according to their membership grades in each cluster. Then a regression model is built for in-sample data using computed prediction limits as targets, and finally, this model is applied to estimate the prediction intervals (limits) for out-of-sample data. The method was tested on artificial and real hydrologic data sets using various machine learning techniques. Preliminary results show that the method is superior to other methods estimating the prediction interval. A new method for evaluating performance for estimating prediction interval is proposed as well.

SINGLE-INTERVAL GAS PERMEABILITY ESTIMATION

EPA Science Inventory

Single-interval, steady-steady-state gas permeability testing requires estimation of pressure at a screened interval which in turn requires measurement of friction factors as a function of mass flow rate. Friction factors can be obtained by injecting air through a length of pipe...

Postmortem Brain and Blood Reference Concentrations of Alprazolam, Bromazepam, Chlordiazepoxide, Diazepam, and their Metabolites and a Review of the Literature.

PubMed

Skov, Louise; Holm, Karen Marie Dollerup; Johansen, Sys Stybe; Linnet, Kristian

2016-09-01

To interpret postmortem toxicology results, reference concentrations for non-toxic and toxic levels are needed. Usually, measurements are performed in blood, but because of postmortem redistribution phenomena this may not be optimal. Rather, measurement in the target organ of psychoactive drugs, the brain, might be considered. Here we present reference concentrations of femoral blood and brain tissue of selected benzodiazepines (BZDs). Using LC-MS/MS, we quantified alprazolam, bromazepam, chlordiazepoxide, diazepam, and the metabolites desmethyldiazepam, oxazepam and temazepam in postmortem femoral blood and brain tissue in 104 cases. BZDs were judged to be unrelated to the cause of death in 88 cases and contributing to death in 16 cases. No cases were found with cause of death solely attributed to BZD poisoning. All BZDs investigated tended to have higher concentrations in brain than in blood with median brain-blood ratios ranging from 1.1 to 2.3. A positive correlation between brain and blood concentrations was found with R(2) values from 0.51 to 0.95. Our reported femoral blood concentrations concur with literature values, but sparse information on brain concentration was available. Drug-metabolite ratios were similar in brain and blood for most compounds. Duplicate measurements of brain samples showed that the pre-analytical variation in brain (5.9%) was relatively low, supporting the notion that brain tissue is a suitable postmortem specimen. The reported concentrations in both brain and blood can be used as reference values when evaluating postmortem cases. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Postmortem evidence of cerebral inflammation in schizophrenia: a systematic review

PubMed Central

Trépanier, M O; Hopperton, K E; Mizrahi, R; Mechawar, N; Bazinet, R P

2016-01-01

Schizophrenia is a psychiatric disorder which has a lifetime prevalence of ~1%. Multiple candidate mechanisms have been proposed in the pathogenesis of schizophrenia. One such mechanism is the involvement of neuroinflammation. Clinical studies, including neuroimaging, peripheral biomarkers and randomized control trials, have suggested the presence of neuroinflammation in schizophrenia. Many studies have also measured markers of neuroinflammation in postmortem brain samples from schizophrenia patients. The objective of this study was to conduct a systematic search of the literature on neuroinflammation in postmortem brains of schizophrenia patients indexed in MEDLINE, Embase and PsycINFO. Databases were searched up until 20th March 2016 for articles published on postmortem brains in schizophrenia evaluating microglia, astrocytes, glia, cytokines, the arachidonic cascade, substance P and other markers of neuroinflammation. Two independent reviewers extracted the data. Out of 5385 articles yielded by the search, 119 articles were identified that measured neuroinflammatory markers in schizophrenic postmortem brains. Glial fibrillary acidic protein expression was elevated, lower or unchanged in 6, 6 and 21 studies, respectively, and similar results were obtained for glial cell densities. On the other hand, microglial markers were increased, lower or unchanged in schizophrenia in 11, 3 and 8 studies, respectively. Results were variable across all other markers, but SERPINA3 and IFITM were consistently increased in 4 and 5 studies, respectively. Despite the variability, some studies evaluating neuroinflammation in postmortem brains in schizophrenia suggest an increase in microglial activity and other markers such as SERPINA3 and IFITM. Variability across studies is partially explained by multiple factors including brain region evaluated, source of the brain, diagnosis, age at time of death, age of onset and the presence of suicide victims in the cohort. PMID:27271499

Downregulated Kynurenine 3-Monooxygenase Gene Expression and Enzyme Activity in Schizophrenia and Genetic Association With Schizophrenia Endophenotypes

PubMed Central

Wonodi, Ikwunga; Stine, O. Colin; Sathyasaikumar, Korrapati V.; Roberts, Rosalinda C.; Mitchell, Braxton D.; Hong, L. Elliot; Kajii, Yasushi; Thaker, Gunvant K.; Schwarcz, Robert

2013-01-01

Context Kynurenic acid, a metabolite of the kynurenine pathway of tryptophan degradation, is an antagonist at N-methyl-d-aspartate and α7 nicotinic acetylcholine receptors and modulates glutamate, dopamine, and acetylcholine signaling. Cortical kynurenic acid concentrations are elevated in the brain and cerebrospinal fluid of schizophrenia patients. The proximal cause may be an impairment of kynurenine 3-monooxygenase (KMO), a rate-limiting enzyme at the branching point of the kynurenine pathway. Objectives To examine KMO messenger RNA expression and KMO enzyme activity in postmortem tissue from the frontal eye field (FEF; Brodmann area 6) obtained from schizophrenia individuals compared with healthy control individuals and to explore the relationship between KMO single-nucleotide polymorphisms and schizophrenia oculomotor endophenotypes. Design Case-control postmortem and clinical study. Setting Maryland Brain Collection, outpatient clinics. Participants Postmortem specimens from schizophrenia patients (n=32) and control donors (n=32) and a clinical sample of schizophrenia patients (n=248) and healthy controls (n=228). Main Outcome Measures Comparison of quantitative KMO messenger RNA expression and KMO enzyme activity in postmortem FEF tissue between schizophrenia patients and controls and association of KMO single-nucleotide polymorphisms with messenger RNA expression in postmortem FEF and schizophrenia and oculomotor endophenotypes (ie, smooth pursuit eye movements and oculomotor delayed response). Results In postmortem tissue, we found a significant and correlated reduction in KMO gene expression and KMO enzyme activity in the FEF in schizophrenia patients. In the clinical sample, KMO rs2275163 was not associated with a diagnosis of schizophrenia but showed modest effects on predictive pursuit and visuospatial working memory endophenotypes. Conclusion Our results provide converging lines of evidence implicating reduced KMO activity in the etiopathophysiology of schizophrenia and related neurocognitive deficits. PMID:21727251

Downregulated kynurenine 3-monooxygenase gene expression and enzyme activity in schizophrenia and genetic association with schizophrenia endophenotypes.

PubMed

Wonodi, Ikwunga; Stine, O Colin; Sathyasaikumar, Korrapati V; Roberts, Rosalinda C; Mitchell, Braxton D; Hong, L Elliot; Kajii, Yasushi; Thaker, Gunvant K; Schwarcz, Robert

2011-07-01

Kynurenic acid, a metabolite of the kynurenine pathway of tryptophan degradation, is an antagonist at N-methyl-d-aspartate and α7 nicotinic acetylcholine receptors and modulates glutamate, dopamine, and acetylcholine signaling. Cortical kynurenic acid concentrations are elevated in the brain and cerebrospinal fluid of schizophrenia patients. The proximal cause may be an impairment of kynurenine 3-monooxygenase (KMO), a rate-limiting enzyme at the branching point of the kynurenine pathway. To examine KMO messenger RNA expression and KMO enzyme activity in postmortem tissue from the frontal eye field (FEF; Brodmann area 6) obtained from schizophrenia individuals compared with healthy control individuals and to explore the relationship between KMO single-nucleotide polymorphisms and schizophrenia oculomotor endophenotypes. Case-control postmortem and clinical study. Maryland Brain Collection, outpatient clinics. Postmortem specimens from schizophrenia patients (n = 32) and control donors (n = 32) and a clinical sample of schizophrenia patients (n = 248) and healthy controls (n = 228). Comparison of quantitative KMO messenger RNA expression and KMO enzyme activity in postmortem FEF tissue between schizophrenia patients and controls and association of KMO single-nucleotide polymorphisms with messenger RNA expression in postmortem FEF and schizophrenia and oculomotor endophenotypes (ie, smooth pursuit eye movements and oculomotor delayed response). In postmortem tissue, we found a significant and correlated reduction in KMO gene expression and KMO enzyme activity in the FEF in schizophrenia patients. In the clinical sample, KMO rs2275163 was not associated with a diagnosis of schizophrenia but showed modest effects on predictive pursuit and visuospatial working memory endophenotypes. Our results provide converging lines of evidence implicating reduced KMO activity in the etiopathophysiology of schizophrenia and related neurocognitive deficits.

Postmortem memantine concentration in a non-intoxication case, and the possibility of postmortem redistribution: A case report.

PubMed

Nagasawa, Sayaka; Yajima, Daisuke; Torimitsu, Suguru; Chiba, Fumiko; Iwase, Hirotaro

2015-12-01

In this case study, we measured the concentration of memantine in the heart blood, peripheral blood, urine, liver, thigh muscle, and subcutaneous fat of a 64-year-old woman who was prescribed memantine for early-onset Alzheimer's disease. She died in hospital after an altercation with her husband. Cause of death was clearly not drug intoxication or overdose, so we investigated the postmortem redistribution (PMR) of memantine in the various tissues and blood ratios of the postmortem samples. Memantine concentrations detected were 1.31 μg/mL in the peripheral blood, 3.95 μg/mL in central blood, 2.09 μg/mL in the urine, 25.54 μg/g in the liver, 1.16 μg/g in the thigh muscle and 2.13 μg/g in the subcutaneous fat. In all samples, the concentrations were higher than the accepted therapeutic range (which is approximately 0.09-0.15 μg/mL). The central blood to peripheral blood (C/P) memantine ratio was 3.01 while the liver to peripheral blood (L/P) ratio was 19.5. It is documented that a C/P ratio exceeding 2 and L/P ratio exceeding 20 highlight a propensity for significant PMR. Although this is a single case study, our data suggest that memantine exhibits PMR. Additionally, a lowered pH was found in peripheral blood (pH 6.2) and central blood (pH 6.1). This postmortem reduction in blood pH may also promote the PMR of memantine. Because there is very little available postmortem toxicological data on memantine, our case study will serve as a foundation to assist in future forensic investigations. Copyright © 2015. Published by Elsevier Ireland Ltd.

The activity ratio of 228Th to 228Ra in bone tissue of recently deceased humans: a new dating method in forensic examinations.

PubMed

Zinka, Bettina; Kandlbinder, Robert; Schupfner, Robert; Haas, Gerald; Wolfbeis, Otto S; Graw, Matthias

2012-01-01

Reliable determination of time since death in human skeletons or single bones often is limited by methodically difficulties. Determination of the specific activity ratio of natural radionuclides, in particular of 232Th (Thorium), 228Th and 228Ra (Radium) seems to be a new appropriate method to calculate the post mortem interval. These radionuclides are incorporated by any human being, mainly from food. So with an individual's death the uptake of radionuclides ends. But the decay of 232Th produces 228Ra and 228Th due to its decay series, whereas 228Th is continuously built up in the human's bones. Thus, it can be concluded that in all deceased humans at different times after death different activity ratios of 228Th to 228Ra will develop in bone. According to this fact it should be possible to calculate time since death of an individual by first analysing the specific activities of 228Th and 228Ra in bones of deceased and then determining the 228Th/228Ra activity ratio, which can be assigned to a certain post-mortem interval.

[Determination of death and post-mortem examination on the high seas].

PubMed

Buschmann, Claas T; Tsokos, Michael

2009-01-01

Usually death has to be determined by a physician. Deaths on board of ocean-going vessels confront the crew with special challenges, as on the high seas--especially in the container and cargo ship business--often no physician will be available and death has to be determined by medical laymen such as the captain or the medical officer. To document the determination of death, a "Provisional Certificate of Death on the High Seas" is presented. Moreover, an algorithm "Provisional Post-Mortem Examination on the High Seas" is presented to document the results and the practical performance of the external post-mortem examination by medical laymen on a ship. With the help of concrete procedural instructions medical laymen on board of sea-going vessels are to be enabled to determine the death of a human being beyond doubt, to perform a preliminary external post-mortem examination and to store the corpse according to forensic requirements until the ship reaches a port and the body is delivered to the harbour physician.

Fetal Cardiac Impairment in Nitrofen-Induced Congenital Diaphragmatic Hernia: Postmortem Microcomputed Tomography Imaging Study.

PubMed

Pelizzo, Gloria; Calcaterra, Valeria; Lombardi, Claudio; Bussani, Rossana; Zambelli, Vanessa; De Silvestri, Annalisa; Custrin, Ana; Belgrano, Manuel; Zennaro, Floriana

2017-08-01

We assessed the post-mortem micro-CT utility to evaluate fetal cardiac impairment in nitrofen-induced congenital diaphragmatic hernia (CDH). At 9.5d postconception (dpc), pregnant rats were exposed to nitrofen. At +18 and +21dpc, fetuses were harvested by cesarean section. Postmortem micro-CT and autopsy were performed. Fetuses were assigned to three experimental groups: Control group (C), Nitrofen group (N, exposition to nitrofen without CDH), CDH group. Cardio-pulmonary indices were evaluated. An accurate morphological evaluation of the lung and heart was obtained. Early cardiac impairment was present in the N and CDH groups. At term pregnancy, an increased maximum diameter and decreased minimum diameter of the ventricles and increased interventricular septal thickness were noted in CDH. Histology showed a myocardial "disarray" and an high density of mitotic myocytes in CDH at midgestation. The potential utility of post-mortem fetal micro-CT examination in CDH was introduced. The results highlighted the presence of cardiac adaptation in affected fetuses.

Involved in the Business of Death: The Social Work Role in Postmortem Care.

PubMed

Sefansky, Susan

2017-02-01

One way that hospitals address concerns about postmortem care is through an office of decedent affairs (ODA). Many hospitals use this office to collect death paperwork, release bodies to funeral homes, perform autopsies, or increase rates of autopsies and organ and tissue donations. It is not common for an ODA to report to the Department of Social Work rather than the Department of Pathology. Few offices put the emphasis on postmortem care for families or staff members. A comprehensive postmortem program needs many different components, including support to families (for example, viewing the dead, advising on next steps after a death, and providing bereavement support), consulting with and supporting multidisciplinary staffers, and coordinating with multiple medical center departments. This article examines a hospital's use of social work principles and clinical training to provide leadership to an ODA and describes the key elements and advantages of a successful program. © 2016 National Association of Social Workers.

Time estimation by patients with frontal lesions and by Korsakoff amnesics.

PubMed

Mimura, M; Kinsbourne, M; O'Connor, M

2000-07-01

We studied time estimation in patients with frontal damage (F) and alcoholic Korsakoff (K) patients in order to differentiate between the contributions of working memory and episodic memory to temporal cognition. In Experiment 1, F and K patients estimated time intervals between 10 and 120 s less accurately than matched normal and alcoholic control subjects. F patients were less accurate than K patients at short (< 1 min) time intervals whereas K patients increasingly underestimated durations as intervals grew longer. F patients overestimated short intervals in inverse proportion to their performance on the Wisconsin Card Sorting Test. As intervals grew longer, overestimation yielded to underestimation for F patients. Experiment 2 involved time estimation while counting at a subjective 1/s rate. F patients' subjective tempo, though relatively rapid, did not fully explain their overestimation of short intervals. In Experiment 3, participants produced predetermined time intervals by depressing a mouse key. K patients underproduced longer intervals. F patients produced comparably to normal participants, but were extremely variable. Findings suggest that both working memory and episodic memory play an individual role in temporal cognition. Turnover within a short-term working memory buffer provides a metric for temporal decisions. The depleted working memory that typically attends frontal dysfunction may result in quicker turnover, and this may inflate subjective duration. On the other hand, temporal estimation beyond 30 s requires episodic remembering, and this puts K patients at a disadvantage.

Severe whipworm (Trichuris spp.) infection in the dromedary (Camelus dromedarius).

PubMed

Eo, Kyung-Yeon; Kwak, Dongmi; Kwon, Oh-Deog

2014-03-01

One adult (13-yr-old) and two young (3-4-yr-old) male dromedary camels (Camelus dromedarius) from the Seoul Zoo displayed anorexia and chronic diarrhea for 2 wk. Direct fecal smear examination revealed Trichuris spp. infection. After confirmation of the infection, fenbendazole was orally administered as a suspension; this was repeated two times at 3-wk intervals. A high initial dose (20 mg/kg) was followed by administration at the recommended dose (10 mg/kg). Starting on the day following the first treatment, a large number of adult whipworms were discharged with the feces over a 3-day period. Two young male dromedary camels gradually recovered. However, the adult male dromedary camel developed continuous bloody mucoid diarrhea and died 2 days after treatment. Postmortem examination revealed that numerous whipworms were attached to the mucosa throughout the large intestine.

TECHNICAL BRIEF: Isolation of total DNA from postmortem human eye tissues and quality comparison between iris and retina

PubMed Central

Wang, Jay Ching Chieh; Wang, Aikun; Gao, Jiangyuan; Cao, Sijia; Samad, Idris; Zhang, Dean; Ritland, Carol; Cui, Jing Z.

2012-01-01

Background Recent genomic technologies have propelled our understanding of the mechanisms underlying complex eye diseases such as age-related macular degeneration (AMD). Genotyping postmortem eye tissues for known single nucleotide polymorphisms (SNPs) associated with AMD may prove valuable, especially when combined with information obtained through other methods such as immunohistochemistry, western blot, enzyme-linked immunosorbent assay (ELISA), and proteomics. Initially intending to genotype postmortem eye tissues for AMD-related SNPs, our group became interested in isolating and comparing the quality of DNA from the iris and retina of postmortem donor eyes. Since there is no previously published protocol in the literature on this topic, we present a protocol suitable for isolating high-quality DNA from postmortem eye tissues for genomic studies. Methods DNA from 33 retinal samples and 35 iris samples was extracted using the phenol-chloroform-isoamyl method from postmortem donor eye tissues. The quantity of DNA was measured with a spectrophotometer while the quality was checked using gel electrophoresis. The DNA samples were then amplified with PCR for the complement factor H (CFH) gene. The purified amplified products were then genotyped for the SNPs in the CFH gene. Results Regarding concentration, the retina yielded 936 ng/μl of DNA, while the iris yielded 78 ng/μl of DNA. Retinal DNA was also purer than iris DNA (260/280=1.78 vs. 1.46, respectively), and produced superior PCR results. Retinal tissue yielded significantly more DNA than the iris tissue per mg of sample (21.7 ng/μl/mg vs. 7.42 ng/μl/mg). Retinal DNA can be readily amplified with PCR, while iris DNA can also be amplified by adding bovine serum albumin. Overall, retinal tissues yielded DNA of superior quality, quantity, and suitability for genotyping and genomic studies. Conclusions The protocol presented here provides a clear and reliable method for isolating total DNA from postmortem eye tissues. Retinal tissue provides DNA of excellent quantity and quality for genotyping and downstream genomic studies. However, DNA isolated from iris tissues, and treated with bovine serum albumin, may also be a valuable source of DNA for genotyping and genomic studies. PMID:23288996

SU-F-I-36: In-Utero Dose Measurements Within Postmortem Subjects for Estimating Fetal Doses in Pregnant Patients Examined with Pulmonary Embolism, Trauma, and Appendicitis CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lipnharski, I; Quails, N; Carranza, C

Purpose: The imaging of pregnant patients is medically necessary in certain clinical situations. The purpose of this work was to directly measure uterine doses in a cadaver scanned with CT protocols commonly performed on pregnant patients in order to estimate fetal dose and assess potential risk. Method: One postmortem subject was scanned on a 320-slice CT scanner with standard pulmonary embolism, trauma, and appendicitis protocols. All protocols were performed with the scan parameters and ranges currently used in clinical practice. Exams were performed both with and without iterative reconstruction to highlight the dose savings potential. Optically stimulated luminescent dosimeters (OSLDs)more » were inserted into the uterus in order to approximate fetal doses. Results: In the pulmonary embolism CT protocol, the uterus is outside of the primary beam, and the dose to the uterus was under 1 mGy. In the trauma and appendicitis protocols, the uterus is in the primary beam, the fetal dose estimates were 30.5 mGy for the trauma protocol, and 20.6 mGy for the appendicitis protocol. Iterative reconstruction reduced fetal doses by 30%, with uterine doses at 21.3 for the trauma and 14.3 mGy for the appendicitis protocol. Conclusion: Fetal doses were under 1 mGy when exposed to scatter radiation, and under 50 mGy when exposed to primary radiation with the trauma and appendicitis protocols. Consistent with the National Council on Radiation Protection & Measurements (NCRP) and the International Commission on Radiological Protection (ICRP), these doses exhibit a negligible risk to the fetus, with only a small increased risk of cancer. Still, CT scans are not recommended during pregnancy unless the benefits of the exam clearly outweigh the potential risk. Furthermore, when possible, pregnant patients should be examined on CT scanners equipped with iterative reconstruction in order to keep patient doses as low as reasonable achievable.« less

Obtaining appropriate interval estimates for age when multiple indicators are used: evaluation of an ad-hoc procedure.

PubMed

Fieuws, Steffen; Willems, Guy; Larsen-Tangmose, Sara; Lynnerup, Niels; Boldsen, Jesper; Thevissen, Patrick

2016-03-01

When an estimate of age is needed, typically multiple indicators are present as found in skeletal or dental information. There exists a vast literature on approaches to estimate age from such multivariate data. Application of Bayes' rule has been proposed to overcome drawbacks of classical regression models but becomes less trivial as soon as the number of indicators increases. Each of the age indicators can lead to a different point estimate ("the most plausible value for age") and a prediction interval ("the range of possible values"). The major challenge in the combination of multiple indicators is not the calculation of a combined point estimate for age but the construction of an appropriate prediction interval. Ignoring the correlation between the age indicators results in intervals being too small. Boldsen et al. (2002) presented an ad-hoc procedure to construct an approximate confidence interval without the need to model the multivariate correlation structure between the indicators. The aim of the present paper is to bring under attention this pragmatic approach and to evaluate its performance in a practical setting. This is all the more needed since recent publications ignore the need for interval estimation. To illustrate and evaluate the method, Köhler et al. (1995) third molar scores are used to estimate the age in a dataset of 3200 male subjects in the juvenile age range.

A Case of Postmortem Canine Depredation.

PubMed

Chute, Dennis J; Bready, Robert J

2017-06-01

We report the case of postmortem animal depredation that produced initial confusion for investigators who responded to the scene. A decomposing elderly woman was found in her presumed home with bilateral upper extremity amputations and craniocerebral trauma. This raised suspicion of foul play. Subsequent investigations together with autopsy led the medical examiner to conclude that the cause of death was natural disease and that those injuries found on her body were produced by at least one of the dogs who shared the premises. We linked the canine culprit to the postmortem trauma and positively identified the remains by collecting material defecated by the animal and by using radiologic and dental comparison techniques.

Fatal Road Traffic Vehicle Collisions With Pedestrian Victims: Forensic Postmortem Computed Tomography and Autopsy Correlation.

PubMed

Chatzaraki, Vasiliki; Thali, Michael J; Ampanozi, Garyfalia; Schweitzer, Wolf

2018-06-01

Fatal car-to-pedestrian collisions regularly appear in the forensic pathologist's routine, particularly in places of extended urbanization. Postmortem computed tomography has gained an exceptional role to supplement autopsy worldwide, giving information that is supplementary or complimentary to conventional autopsy. In this retrospective study, a total number of 320 findings in a series of 21 pedestrians fatally hit by cars and trucks of both postmortem computed tomography and autopsy were correlated. According to our results, it is best to combine both methods to give well-founded answers to questions pertaining to both collision reconstruction and cause of death.

Computer-assisted virtual autopsy using surgical navigation techniques.

PubMed

Ebert, Lars Christian; Ruder, Thomas D; Martinez, Rosa Maria; Flach, Patricia M; Schweitzer, Wolf; Thali, Michael J; Ampanozi, Garyfalia

2015-01-01

OBJECTIVE; Virtual autopsy methods, such as postmortem CT and MRI, are increasingly being used in forensic medicine. Forensic investigators with little to no training in diagnostic radiology and medical laypeople such as state's attorneys often find it difficult to understand the anatomic orientation of axial postmortem CT images. We present a computer-assisted system that permits postmortem CT datasets to be quickly and intuitively resliced in real time at the body to narrow the gap between radiologic imaging and autopsy. Our system is a potentially valuable tool for planning autopsies, showing findings to medical laypeople, and teaching CT anatomy, thus further closing the gap between radiology and forensic pathology.

Estimating equivalence with quantile regression

USGS Publications Warehouse

Cade, B.S.

2011-01-01

Equivalence testing and corresponding confidence interval estimates are used to provide more enlightened statistical statements about parameter estimates by relating them to intervals of effect sizes deemed to be of scientific or practical importance rather than just to an effect size of zero. Equivalence tests and confidence interval estimates are based on a null hypothesis that a parameter estimate is either outside (inequivalence hypothesis) or inside (equivalence hypothesis) an equivalence region, depending on the question of interest and assignment of risk. The former approach, often referred to as bioequivalence testing, is often used in regulatory settings because it reverses the burden of proof compared to a standard test of significance, following a precautionary principle for environmental protection. Unfortunately, many applications of equivalence testing focus on establishing average equivalence by estimating differences in means of distributions that do not have homogeneous variances. I discuss how to compare equivalence across quantiles of distributions using confidence intervals on quantile regression estimates that detect differences in heterogeneous distributions missed by focusing on means. I used one-tailed confidence intervals based on inequivalence hypotheses in a two-group treatment-control design for estimating bioequivalence of arsenic concentrations in soils at an old ammunition testing site and bioequivalence of vegetation biomass at a reclaimed mining site. Two-tailed confidence intervals based both on inequivalence and equivalence hypotheses were used to examine quantile equivalence for negligible trends over time for a continuous exponential model of amphibian abundance. ?? 2011 by the Ecological Society of America.

The Design and Development of a Post-Mortem Room Complex

ERIC Educational Resources Information Center

Osborne, A. D.

1977-01-01

The design of a post-mortem room complex to serve the needs of three separate organizations on the campus of the University of Bristol's Veterinary Field Station is described. Comments are made on disadvantages that have become apparent during eight years of use. (Author/LBH)

Estimating fluvial wood discharge from timelapse photography with varying sampling intervals

NASA Astrophysics Data System (ADS)

Anderson, N. K.

2013-12-01

There is recent focus on calculating wood budgets for streams and rivers to help inform management decisions, ecological studies and carbon/nutrient cycling models. Most work has measured in situ wood in temporary storage along stream banks or estimated wood inputs from banks. Little effort has been employed monitoring and quantifying wood in transport during high flows. This paper outlines a procedure for estimating total seasonal wood loads using non-continuous coarse interval sampling and examines differences in estimation between sampling at 1, 5, 10 and 15 minutes. Analysis is performed on wood transport for the Slave River in Northwest Territories, Canada. Relative to the 1 minute dataset, precision decreased by 23%, 46% and 60% for the 5, 10 and 15 minute datasets, respectively. Five and 10 minute sampling intervals provided unbiased equal variance estimates of 1 minute sampling, whereas 15 minute intervals were biased towards underestimation by 6%. Stratifying estimates by day and by discharge increased precision over non-stratification by 4% and 3%, respectively. Not including wood transported during ice break-up, the total minimum wood load estimated at this site is 3300 × 800$ m3 for the 2012 runoff season. The vast majority of the imprecision in total wood volumes came from variance in estimating average volume per log. Comparison of proportions and variance across sample intervals using bootstrap sampling to achieve equal n. Each trial was sampled for n=100, 10,000 times and averaged. All trials were then averaged to obtain an estimate for each sample interval. Dashed lines represent values from the one minute dataset.

Fatty acid composition of the postmortem corpus callosum of patients with schizophrenia, bipolar disorder, or major depressive disorder.

PubMed

Hamazaki, K; Maekawa, M; Toyota, T; Dean, B; Hamazaki, T; Yoshikawa, T

2017-01-01

Studies investigating the relationship between n-3 polyunsaturated fatty acid (PUFA) levels and psychiatric disorders have thus far focused mainly on analyzing gray matter, rather than white matter, in the postmortem brain. In this study, we investigated whether PUFA levels showed abnormalities in the corpus callosum, the largest area of white matter, in the postmortem brain tissue of patients with schizophrenia, bipolar disorder, or major depressive disorder. Fatty acids in the phospholipids of the postmortem corpus callosum were evaluated by thin-layer chromatography and gas chromatography. Specimens were evaluated for patients with schizophrenia (n=15), bipolar disorder (n=15), or major depressive disorder (n=15) and compared with unaffected controls (n=15). In contrast to some previous studies, no significant differences were found in the levels of PUFAs or other fatty acids in the corpus callosum between patients and controls. A subanalysis by sex gave the same results. No significant differences were found in any PUFAs between suicide completers and non-suicide cases regardless of psychiatric disorder diagnosis. Patients with psychiatric disorders did not exhibit n-3 PUFAs deficits in the postmortem corpus callosum relative to the unaffected controls, and the corpus callosum might not be involved in abnormalities of PUFA metabolism. This area of research is still at an early stage and requires further investigation. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Effects of boning method and postmortem aging on meat quality characteristics of pork loin.

PubMed

Li, Chunbao; Wu, Juqing; Zhang, Nan; Zhang, Song; Liu, Juan; Li, Jinping; Li, Hongmin; Feng, Xianchao; Han, Yanqing; Zhu, Zhiyuan; Xu, Xinglian; Zhou, Guanghong

2009-10-01

This work investigated the effects of boning method and postmortem aging on pork loin color, shearing value and sensory attributes. Two experiments were assigned. In Experiment I, 30 Chinese native black pigs were slaughtered and their carcasses were divided into three groups: (i) hot-boning: carcasses were fabricated within 45 min postmortem just after dressing; (ii) cold boning at 24 h: carcasses were fabricated after chilling at 0 degrees C for 24 h; (iii) cold boning at 36 h: carcasses were fabricated after chilling at 0 degrees C for 36 h. In Experiment II, right sides of the second group in Experiment I were used and primal cuts were vacuum packed and aged for 1 day, 8 days and 16 days. Pork loins (Longissimus lumborum) were used for color measurement, shearing test, and sensory evaluation. Among three boning methods, cold-boning at 36 h postmortem had the advantages of giving muscles a better color, the lowest cooking loss and cooked shearing value, and the highest sensory tenderness, juiciness, flavor and overall liking. Postmortem aging could improve pork quality characteristics, but it is not the fact that the longer aging time is, the better pork quality would be. Eight days may be enough to obtain an acceptable sensory attribute. These results are meaningful for pork processing and pork consumption.

Caspase inhibitors increase the rate of recovery of neural stem/progenitor cells from post-mortem rat brains stored at room temperature.

PubMed

Hasegawa, Atsuko; Yamada, Chikako; Tani, Miho; Hirano, Shun-ichiro; Tokumoto, Yasuhito; Miyake, Jun

2009-06-01

To match the demand of regenerative medicine for nerve system, collection of stem cells from the post-mortem body is one of the most practical ways. In this study, the storage condition of the post-mortem body was examined. We prepared neural stem/progenitor cells (NSPCs) from post-mortem rat brains stored at different temperatures. When brains were stored at 4 degrees C, for one week, we were able to obtain neurospheres (a spheroid body containing NSPCs) by stimulation of cells with epidermal growth factor (EGF). Incremental increases in storage temperature decreased the rate of appearance of neurospheres. Within 48 h at 15 degrees C, 24 h at 25 degrees C, in both condition, we were able to recover NSPCs from post-mortem rat brains. At 15 degrees C, 90% of neurosphere-forming activity was lost within 24 h. However, even after 24 h at 25 degrees C, 2% neurosphere-forming activity remained. After 6 h of death, there was very little difference between the rates of NSPC recovery at 4 degrees C and 25 degrees C. Addition of caspase inhibitors to both the rat brain storage solution and the NSPC culture medium increased the rate of neurosphere-forming activity. In particular, an inhibitor of caspase-8 activity increased the NSPC recovery rate approximately three-fold, with no accompanying detrimental effects on neural differentiation in vitro.

Histological findings and immunohistochemical surfactant protein A (SP-A) expression in asphyxia: its application in the diagnosis of drowning.

PubMed

Pérez-Cárceles, M D; Sibón, A; Vizcaya, M A; Osuna, E; Gómez-Zapata, M; Luna, A; Martínez-Díaz, F

2008-09-01

The histopathological alterations that permit the diagnosis of death by asphyxia are very unspecific, although pulmonary alterations are of great importance in this respect. The postmortem diagnosis of drowning, particularly, continues to be one of the most difficult in forensic pathology. The aim of this study is to jointly evaluate microscopic findings and immunohistochemical surfactant protein A (SP-A) expression in the upper and lower lobes of lungs in different causes of death, and their possible application to the diagnosis of drowning. We studied 120 cadavers from subjects with a mean age of 48.73 years (SD 19.45; range 2-86 years), and with a mean post-mortem interval of 30 hours (SD 39.59; range 3-216 hours). According to the scene, cause and circumstances of death, and autopsy findings, cases were classified into groups as follows: (a) drowning (n=47); (b) other asphyxia (n=44) and (c) other causes (n=29). In the upper and lower lobes of lungs, histological studies of H&E staining and immunohistochemical surfactant protein A expression were made. The presence and severity of congestion, haemorrhage and oedema, together with immunohistochemical SP-A expression, may have a diagnostic value in differentiating asphyxia and drowning from other causes of death, and drowning from other types of asphyxia. Our findings suggest that both lobes should be investigated to establish the diagnosis, although the findings in the upper lobe might be the most important for differentiating the exact cause of death.

Drug concentrations in post-mortem femoral blood compared with therapeutic concentrations in plasma

PubMed Central

Launiainen, Terhi; Ojanperä, Ilkka

2014-01-01

Therapeutic drug concentrations measured in plasma are of limited value as reference intervals for interpretation in post-mortem (PM) toxicology. In this study, drug concentration distributions were studied in PM femoral venous blood from 57 903 Finnish autopsy cases representing all causes of death during an 11-year period. Cause-of-death information was obtained from death certificates issued by forensic pathologists. Median, mean, and upper percentile (90th, 95th, 97.5th) concentrations were calculated for 129 drugs. To illustrate how PM median concentrations relate to established therapeutic ranges in plasma, a PM blood/plasma relationship was calculated for each drug. Males represented 75% of the subjects and showed a lower median age (55 yrs) than females (59 yrs). In 43% of these cases, blood alcohol concentration was higher than 0.2‰, and the median was 1.8‰. Sixty-one (47%) of the 129 drugs showed a PM blood/plasma relationship of 1. For 22 drugs (17%), the relationship was <1, and for 46 drugs (35%), the relationship was >1. No marked correlation was found between the PM blood/plasma relationship and the volume of distribution (Vd). For 36 drugs, more than 10% of cases were fatal poisonings attributed to this drug as the main finding. These drug concentration distributions based on a large database provide a helpful reference not only to forensic toxicologists and pathologists but also to clinical pharmacologists in charge of interpreting drug concentrations in PM cases. © 2013 The Authors. Drug Testing and Analysis published by John Wiley & Sons, Ltd. PMID:23881890

Diagnostic accuracy and limitations of post-mortem MRI for neurological abnormalities in fetuses and children.

PubMed

Arthurs, O J; Thayyil, S; Pauliah, S S; Jacques, T S; Chong, W K; Gunny, R; Saunders, D; Addison, S; Lally, P; Cady, E; Jones, R; Norman, W; Scott, R; Robertson, N J; Wade, A; Chitty, L; Taylor, A M; Sebire, N J

2015-08-01

To compare the diagnostic accuracy of non-invasive cerebral post-mortem magnetic resonance imaging (PMMRI) specifically for cerebral and neurological abnormalities in a series of fetuses and children, compared to conventional autopsy. Institutional ethics approval and parental consent was obtained. Pre-autopsy cerebral PMMRI was performed in a sequential prospective cohort (n = 400) of fetuses (n = 277; 185 ≤ 24 weeks and 92 > 24 weeks gestation) and children <16 years (n = 123) of age. PMMRI and conventional autopsy findings were reported blinded and independently of each other. Cerebral PMMRI had sensitivities and specificities (95% confidence interval) of 88.4% (75.5 to 94.9), and 95.2% (92.1 to 97.1), respectively, for cerebral malformations; 100% (83.9 to 100), and 99.1% (97.2 to 99.7) for major intracranial bleeds; and 87.5% (80.1 to 92.4) and 74.1% (68 to 79.4) for overall brain pathology. Formal neuropathological examination was non-diagnostic due to maceration/autolysis in 43/277 (16%) fetuses; of these, cerebral PMMRI imaging provided clinically important information in 23 (53%). The sensitivity of PMMRI for detecting significant ante-mortem ischaemic injury was only 68% (48.4 to 82.8) overall. PMMRI is an accurate investigational technique for identifying significant neuropathology in fetuses and children, and may provide important information even in cases where autolysis prevents formal neuropathological examination; however, PMMRI is less sensitive at detecting hypoxic-ischaemic brain injury, and may not detect rarer disorders not encountered in this study. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

9 CFR 355.41 - Antemortem and postmortem inspection for mules.

Code of Federal Regulations, 2014 CFR

2014-01-01

... for mules. 355.41 Section 355.41 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...; INSPECTION, CERTIFICATION, AND IDENTIFICATION AS TO CLASS, QUALITY, QUANTITY, AND CONDITION Mule Meat and Animal Food, Mule Meat By-Product § 355.41 Antemortem and postmortem inspection for mules. (a)(1) An...

9 CFR 355.41 - Antemortem and postmortem inspection for mules.

Code of Federal Regulations, 2013 CFR

2013-01-01

... for mules. 355.41 Section 355.41 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...; INSPECTION, CERTIFICATION, AND IDENTIFICATION AS TO CLASS, QUALITY, QUANTITY, AND CONDITION Mule Meat and Animal Food, Mule Meat By-Product § 355.41 Antemortem and postmortem inspection for mules. (a)(1) An...

9 CFR 355.41 - Antemortem and postmortem inspection for mules.

Code of Federal Regulations, 2011 CFR

2011-01-01

... for mules. 355.41 Section 355.41 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...; INSPECTION, CERTIFICATION, AND IDENTIFICATION AS TO CLASS, QUALITY, QUANTITY, AND CONDITION Mule Meat and Animal Food, Mule Meat By-Product § 355.41 Antemortem and postmortem inspection for mules. (a)(1) An...

9 CFR 355.41 - Antemortem and postmortem inspection for mules.

Code of Federal Regulations, 2012 CFR

2012-01-01

... for mules. 355.41 Section 355.41 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...; INSPECTION, CERTIFICATION, AND IDENTIFICATION AS TO CLASS, QUALITY, QUANTITY, AND CONDITION Mule Meat and Animal Food, Mule Meat By-Product § 355.41 Antemortem and postmortem inspection for mules. (a)(1) An...

Alterations in the sarcoplasmic protein fraction of beef muscle with postmortem aging and hydrodynamic pressure processing

USDA-ARS?s Scientific Manuscript database

Capillary electrophoresis (CE) and reversed-phase high performance liquid chromatography (RP-HPLC) analysis were utilized to detect differences in the sarcoplasmic protein profiles of beef strip loins subjected to aging and hydrodynamic pressure processing (HDP) treatments. At 48 h postmortem, stri...

Precision Interval Estimation of the Response Surface by Means of an Integrated Algorithm of Neural Network and Linear Regression

NASA Technical Reports Server (NTRS)

Lo, Ching F.

1999-01-01

The integration of Radial Basis Function Networks and Back Propagation Neural Networks with the Multiple Linear Regression has been accomplished to map nonlinear response surfaces over a wide range of independent variables in the process of the Modem Design of Experiments. The integrated method is capable to estimate the precision intervals including confidence and predicted intervals. The power of the innovative method has been demonstrated by applying to a set of wind tunnel test data in construction of response surface and estimation of precision interval.

Potential confounding in the association between short birth intervals and increased neonatal, infant, and child mortality

PubMed Central

Perin, Jamie; Walker, Neff

2015-01-01

Background Recent steep declines in child mortality have been attributed in part to increased use of contraceptives and the resulting change in fertility behaviour, including an increase in the time between births. Previous observational studies have documented strong associations between short birth spacing and an increase in the risk of neonatal, infant, and under-five mortality, compared to births with longer preceding birth intervals. In this analysis, we compare two methods to estimate the association between short birth intervals and mortality risk to better inform modelling efforts linking family planning and mortality in children. Objectives Our goal was to estimate the mortality risk for neonates, infants, and young children by preceding birth space using household survey data, controlling for mother-level factors and to compare the results to those from previous analyses with survey data. Design We assessed the potential for confounding when estimating the relative mortality risk by preceding birth interval and estimated mortality risk by birth interval in four categories: less than 18 months, 18–23 months, 24–35 months, and 36 months or longer. We estimated the relative risks among women who were 35 and older at the time of the survey with two methods: in a Cox proportional hazards regression adjusting for potential confounders and also by stratifying Cox regression by mother, to control for all factors that remain constant over a woman's childbearing years. We estimated the overall effects for birth spacing in a meta-analysis with random survey effects. Results We identified several factors known for their associations with neonatal, infant, and child mortality that are also associated with preceding birth interval. When estimating the effect of birth spacing on mortality, we found that regression adjustment for these factors does not substantially change the risk ratio for short birth intervals compared to an unadjusted mortality ratio. For birth intervals less than 18 months, standard regression adjustment for confounding factors estimated a risk ratio for neonatal mortality of 2.28 (95% confidence interval: 2.18–2.37). This same effect estimated within mother is 1.57 (95% confidence interval: 1.52–1.63), a decline of almost one-third in the effect on neonatal mortality. Conclusions Neonatal, infant, and child mortality are strongly and significantly related to preceding birth interval, where births within a short interval of time after the previous birth have increased mortality. Previous analyses have demonstrated this relationship on average across all births; however, women who have short spaces between births are different from women with long spaces. Among women 35 years and older where a comparison of birth spaces within mother is possible, we find a much reduced although still significant effect of short birth spaces on child mortality. PMID:26562139

Potential confounding in the association between short birth intervals and increased neonatal, infant, and child mortality.

PubMed

Perin, Jamie; Walker, Neff

2015-01-01

Recent steep declines in child mortality have been attributed in part to increased use of contraceptives and the resulting change in fertility behaviour, including an increase in the time between births. Previous observational studies have documented strong associations between short birth spacing and an increase in the risk of neonatal, infant, and under-five mortality, compared to births with longer preceding birth intervals. In this analysis, we compare two methods to estimate the association between short birth intervals and mortality risk to better inform modelling efforts linking family planning and mortality in children. Our goal was to estimate the mortality risk for neonates, infants, and young children by preceding birth space using household survey data, controlling for mother-level factors and to compare the results to those from previous analyses with survey data. We assessed the potential for confounding when estimating the relative mortality risk by preceding birth interval and estimated mortality risk by birth interval in four categories: less than 18 months, 18-23 months, 24-35 months, and 36 months or longer. We estimated the relative risks among women who were 35 and older at the time of the survey with two methods: in a Cox proportional hazards regression adjusting for potential confounders and also by stratifying Cox regression by mother, to control for all factors that remain constant over a woman's childbearing years. We estimated the overall effects for birth spacing in a meta-analysis with random survey effects. We identified several factors known for their associations with neonatal, infant, and child mortality that are also associated with preceding birth interval. When estimating the effect of birth spacing on mortality, we found that regression adjustment for these factors does not substantially change the risk ratio for short birth intervals compared to an unadjusted mortality ratio. For birth intervals less than 18 months, standard regression adjustment for confounding factors estimated a risk ratio for neonatal mortality of 2.28 (95% confidence interval: 2.18-2.37). This same effect estimated within mother is 1.57 (95% confidence interval: 1.52-1.63), a decline of almost one-third in the effect on neonatal mortality. Neonatal, infant, and child mortality are strongly and significantly related to preceding birth interval, where births within a short interval of time after the previous birth have increased mortality. Previous analyses have demonstrated this relationship on average across all births; however, women who have short spaces between births are different from women with long spaces. Among women 35 years and older where a comparison of birth spaces within mother is possible, we find a much reduced although still significant effect of short birth spaces on child mortality.

Overconfidence in Interval Estimates: What Does Expertise Buy You?

ERIC Educational Resources Information Center

McKenzie, Craig R. M.; Liersch, Michael J.; Yaniv, Ilan

2008-01-01

People's 90% subjective confidence intervals typically contain the true value about 50% of the time, indicating extreme overconfidence. Previous results have been mixed regarding whether experts are as overconfident as novices. Experiment 1 examined interval estimates from information technology (IT) professionals and UC San Diego (UCSD) students…

Estimation of aquifer scale proportion using equal area grids: assessment of regional scale groundwater quality

USGS Publications Warehouse

Belitz, Kenneth; Jurgens, Bryant C.; Landon, Matthew K.; Fram, Miranda S.; Johnson, Tyler D.

2010-01-01

The proportion of an aquifer with constituent concentrations above a specified threshold (high concentrations) is taken as a nondimensional measure of regional scale water quality. If computed on the basis of area, it can be referred to as the aquifer scale proportion. A spatially unbiased estimate of aquifer scale proportion and a confidence interval for that estimate are obtained through the use of equal area grids and the binomial distribution. Traditionally, the confidence interval for a binomial proportion is computed using either the standard interval or the exact interval. Research from the statistics literature has shown that the standard interval should not be used and that the exact interval is overly conservative. On the basis of coverage probability and interval width, the Jeffreys interval is preferred. If more than one sample per cell is available, cell declustering is used to estimate the aquifer scale proportion, and Kish's design effect may be useful for estimating an effective number of samples. The binomial distribution is also used to quantify the adequacy of a grid with a given number of cells for identifying a small target, defined as a constituent that is present at high concentrations in a small proportion of the aquifer. Case studies illustrate a consistency between approaches that use one well per grid cell and many wells per cell. The methods presented in this paper provide a quantitative basis for designing a sampling program and for utilizing existing data.

Aspartic acid racemisation in purified elastin from arteries as basis for age estimation.

PubMed

Dobberstein, R C; Tung, S-M; Ritz-Timme, S

2010-07-01

Aspartic acid racemisation (AAR) results in an age-dependent accumulation of D: -aspartic acid in durable human proteins and can be used as a basis for age estimation. Routinely, age estimation based on AAR is performed by analysis of dentine. However, in forensic practise, teeth are not always available. Non-dental tissues for age estimation may be suitable for age estimation based on AAR if they contain durable proteins that can be purified and analysed. Elastin is such a durable protein. To clarify if purified elastin from arteries is a suitable sample for biochemical age estimation, AAR was determined in purified elastin from arteries from individuals of known age (n = 68 individuals, including n = 15 putrefied corpses), considering the influence of different stages of atherosclerosis and putrefaction on the AAR values. AAR was found to increase with age. The relationship between AAR and age was good enough to serve as basis for age estimation, but worse than known from dentinal proteins. Intravital and post-mortem degradation of elastin may have a moderate effect on the AAR values. Age estimation based on AAR in purified elastin from arteries may be a valuable additional tool in the identification of unidentified cadavers, especially in cases where other methods cannot be applied (e.g., no available teeth and body parts).

Fatal intoxication with synthetic cannabinoid MDMB-CHMICA.

PubMed

Adamowicz, Piotr

2016-04-01

MDMB-CHMICA is a synthetic cannabinoid that appeared on the European drug market in September 2014. This substance was found in Poland in the herbal mixture "Mocarz" ("Strongman"), which caused a large outbreak of intoxications at the beginning of July 2015. This paper describes the circumstances of death and toxicological findings in a fatal intoxication with MDMB-CHMICA (in combination with alcohol). Loss of consciousness and asystole occurred a few minutes after smoking the 'legal high'. The man died after 4 days of hospitalisation. The cause of death accepted by the medical examiner was multiple organ failure. MDMB-CHMICA was detected and quantified in blood (ante- and postmortem) and internal organs tissues. The samples were analysed using liquid chromatography with mass spectrometry (LC-MS/MS). The concentration of MDMB-CHMICA in antemortem blood was 5.6 ng/mL. Although the death occurred after 4 days from administration a relatively high concentration (2.6 ng/g) was estimated in the brain. Traces of this compound were also found in other postmortem materials (blood, stomach, liver, bile, and kidney). The presented case shows the health risks associated with MDMB-CHMICA use. The administration of this substance can lead to the number of organ failures, cardiac arrest and consequently death. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Immunohistochemistry of catecholamines in the hypothalamic-pituitary-adrenal system with special regard to fatal hypothermia and hyperthermia.

PubMed

Ishikawa, Takaki; Yoshida, Chiemi; Michiue, Tomomi; Perdekamp, Markus Grosse; Pollak, Stefan; Maeda, Hitoshi

2010-05-01

Catecholamines are involved in various stress responses. Previous studies have suggested applicability of the postmortem blood levels to investigations of physical stress responses or toxic/hyperthermic neuronal dysfunction during death process. The present study investigated cellular immunopositivity for adrenaline (Adr), noradrenaline (Nad) and dopamine (DA) in the hypothalamus, adenohypophysis and adrenal medulla with special regard to fatal hypothermia (cold exposure) and hyperthermia (heat stroke) to examine forensic pathological significance. Medicolegal autopsy cases (n=290, within 3 days postmortem) were examined. The proportions of catecholamine (Adr, Nad and DA)-positive cells (% positivity) in each tissue were quantitatively estimated using immunostaining. Hyperthermia cases (n=12) showed a lower neuronal DA-immunopositivity in the hypothalamus than hypothermia cases (n=20), while Nad- and DA-immunopositivities in the adrenal medulla were higher for hyperthermia than for hypothermia. Rates of Nad-immunopositivity in the adrenal medulla were very low for hypothermia. No such difference between hypothermia and hyperthermia was seen in the adenohypophysis. In hypothermia cases, cellular Nad-immunopositivity in the adrenal medulla correlated with the Nad level in cerebrospinal fluid (r=0.591, p<0.01). These observations suggest a characteristic immunohistochemical pattern of systemic stress response to fatal hypothermia and hyperthermia, involving the hypothalamus and adrenal medulla. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Numerical investigations on pressurized AL-composite vessel response to hypervelocity impacts: Comparison between experimental works and a numerical code

NASA Astrophysics Data System (ADS)

Mespoulet, Jérôme; Plassard, Fabien; Hereil, Pierre-Louis

2015-09-01

Response of pressurized composite-Al vessels to hypervelocity impact of aluminum spheres have been numerically investigated to evaluate the influence of initial pressure on the vulnerability of these vessels. Investigated tanks are carbon-fiber overwrapped prestressed Al vessels. Explored internal air pressure ranges from 1 bar to 300 bar and impact velocity are around 4400 m/s. Data obtained from experiments (Xray radiographies, particle velocity measurement and post-mortem vessels) have been compared to numerical results given from LS-DYNA ALE-Lagrange-SPH full coupling models. Simulations exhibit an under estimation in term of debris cloud evolution and shock wave propagation in pressurized air but main modes of damage/rupture on the vessels given by simulations are coherent with post-mortem recovered vessels from experiments. First results of this numerical work are promising and further simulation investigations with additional experimental data will be done to increase the reliability of the simulation model. The final aim of this crossed work is to numerically explore a wide range of impact conditions (impact angle, projectile weight, impact velocity, initial pressure) that cannot be explore experimentally. Those whole results will define a rule of thumbs for the definition of a vulnerability analytical model for a given pressurized vessel.

Assessment of cardiovascular disease in the donkey: clinical, echocardiographic and pathological observations.

PubMed

Roberts, S L; Dukes-McEwan, J

2016-10-15

The Donkey Sanctuary (DS) owns 3500-4000 donkeys, estimated to be about 35 per cent of the UK population. Although postmortem surveys suggest a high prevalence of cardiovascular disease in donkeys, there is sparse clinical information about cardiovascular examination findings and echocardiographic findings in health and disease. In this cross-sectional study, auscultation findings were recorded, and in a subset of donkeys, echocardiography was used to screen for structural and functional cardiac disease. 202 donkeys were examined; 117 geldings and 85 females. Heart sounds S1 and S2 were detected in all donkeys, but none had audible S3. S4 was detected in nine (4.5 per cent; significantly older than those without S4; P<0.001). A heart murmur was detected in four donkeys. Echocardiography identified these to be due to a ventricular septal defect in one, and aortic regurgitation in three. An additional 43 donkeys had echocardiography. A further 10 donkeys were identified to have aortic insufficiency, but no other valvular regurgitation. 76/202 donkeys subsequently underwent postmortem examination. Three showed degenerative aortic valve changes. One donkey had nodular lesions in the intima of proximal aorta and sinus of Valsalva. Histopathology showed multifocal chronic nodular eosinophilic arteritis, consistent with verminous arteritis. The DS pathology database identified other similar cases. British Veterinary Association.

Major causes of organ/carcass condemnation and financial loss estimation in animals slaughtered at two abattoirs in Bursa Province, Turkey.

PubMed

Yibar, Artun; Selcuk, Ozgur; Senlik, Bayram

2015-01-01

An abattoir survey was conducted from July 2012 to December 2012 to determine the major causes of organ and carcass condemnation and to estimate the associated direct financial loss at two abattoirs in Bursa Province in Turkey. A total of 22,872 sheeps and 5363 cattle were examined by postmortem inspection using standard inspection procedures. The total economic loss in two abattoirs was estimated from the summation of organ and carcass condemnation in six-month period. The retail prices of offal (lung, liver, kidney, heart, and spleen) and kg price of cattle and sheep carcasses were obtained from local markets. The results of postmortem examination indicated that a total of 658 (2.33%) offals and 93 (0.32%) carcasses were condemned. While the main causes of organ condemnation were hydatidosis and fasciolosis, carcasses were condemned mainly due to tuberculosis and jaundice. The total revenue in 2012 for all animals (164,080 sheeps and 56,035 cattle) slaughtered in 15 abattoirs in Bursa Province was 144,401,765 USD. This study showed that financial loss due to organ and carcass condemnations at two abattoirs in six-month period was 245,483 USD (0.17% of the total annual revenue of all slaughtered animals at 15 abattoirs). In sheep, six-month financial loss was estimated at 3281 USD and 4015 USD from organ condemnation due to fasciolosis and hydatidosis, respectively. In cattle, total loss was calculated as 4042 USD and 12,321 USD due to fasciolosis and hydatidosis, respectively. A common cause of carcass condemnation in cattle was tuberculosis, totalling 214,995 USD in losses, whereas condemnation due to tuberculosis was not determined in sheep. The current study also showed that six-month monetary losses from carcass condemnation of sheep and cattle due to jaundice were 8099 USD and 6026 USD, respectively. From the data obtained in this study, it can be concluded that bacterial and parasitic diseases remain common and cause considerable economic loss in Bursa Province, Turkey. The result of this abattoir study provided regional information on major causes of organ and carcass condemnation in sheep and cattle slaughtered at two abattoirs as well as giving an estimation of the direct financial losses. Copyright © 2014 Elsevier B.V. All rights reserved.

Optimal Measurement Interval for Emergency Department Crowding Estimation Tools.

PubMed

Wang, Hao; Ojha, Rohit P; Robinson, Richard D; Jackson, Bradford E; Shaikh, Sajid A; Cowden, Chad D; Shyamanand, Rath; Leuck, JoAnna; Schrader, Chet D; Zenarosa, Nestor R

2017-11-01

Emergency department (ED) crowding is a barrier to timely care. Several crowding estimation tools have been developed to facilitate early identification of and intervention for crowding. Nevertheless, the ideal frequency is unclear for measuring ED crowding by using these tools. Short intervals may be resource intensive, whereas long ones may not be suitable for early identification. Therefore, we aim to assess whether outcomes vary by measurement interval for 4 crowding estimation tools. Our eligible population included all patients between July 1, 2015, and June 30, 2016, who were admitted to the JPS Health Network ED, which serves an urban population. We generated 1-, 2-, 3-, and 4-hour ED crowding scores for each patient, using 4 crowding estimation tools (National Emergency Department Overcrowding Scale [NEDOCS], Severely Overcrowded, Overcrowded, and Not Overcrowded Estimation Tool [SONET], Emergency Department Work Index [EDWIN], and ED Occupancy Rate). Our outcomes of interest included ED length of stay (minutes) and left without being seen or eloped within 4 hours. We used accelerated failure time models to estimate interval-specific time ratios and corresponding 95% confidence limits for length of stay, in which the 1-hour interval was the reference. In addition, we used binomial regression with a log link to estimate risk ratios (RRs) and corresponding confidence limit for left without being seen. Our study population comprised 117,442 patients. The time ratios for length of stay were similar across intervals for each crowding estimation tool (time ratio=1.37 to 1.30 for NEDOCS, 1.44 to 1.37 for SONET, 1.32 to 1.27 for EDWIN, and 1.28 to 1.23 for ED Occupancy Rate). The RRs of left without being seen differences were also similar across intervals for each tool (RR=2.92 to 2.56 for NEDOCS, 3.61 to 3.36 for SONET, 2.65 to 2.40 for EDWIN, and 2.44 to 2.14 for ED Occupancy Rate). Our findings suggest limited variation in length of stay or left without being seen between intervals (1 to 4 hours) regardless of which of the 4 crowding estimation tools were used. Consequently, 4 hours may be a reasonable interval for assessing crowding with these tools, which could substantially reduce the burden on ED personnel by requiring less frequent assessment of crowding. Copyright © 2017 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

[Three good reasons to perform a postmortem examination in all cases of juvenile sudden death].

PubMed

d'Amati, Giulia; di Gioia, Cira R T; Silenzi, Paola F; Gallo, Pietro

2009-04-01

The aim of this review is to underline the reasons why a post-mortem examination has to be performed in all cases of juvenile sudden death. Sudden death in children and young adults can be caused by potentially heritable cardiovascular disorders and fatal outcome is often the first symptom in apparently healthy subjects. In these cases, a careful autopsy, performed according to a standardized protocol, becomes the sole diagnostic tool to guide clinical and molecular genetic family screening and to adopt the proper therapeutic and preventive strategies. Thus, a post-mortem examination is a fundamental part of a multidisciplinary approach to the issue of juvenile sudden death.

Postmortem aviation forensic toxicology: an overview.

PubMed

Chaturvedi, Arvind K

2010-05-01

An overview of the subtopic aviation combustion toxicology of the field of aerospace toxicology has been published. In a continuation of the overview, the findings associated with postmortem aviation forensic toxicology are being summarized in the present overview. A literature search for the period of 1960-2007 was performed. The important findings related to postmortem toxicology were evaluated. In addition to a brief introduction, this overview is divided into the sections of analytical methods; carboxyhemoglobin and blood cyanide ion; ethanol; drugs; result interpretation; glucose and hemoglobin A(1c); and references. Specific details of the subject matter were discussed. It is anticipated that this overview will be an outline source for aviation forensic toxicology within the field of aerospace toxicology.

Interval Timing Accuracy and Scalar Timing in C57BL/6 Mice

PubMed Central

Buhusi, Catalin V.; Aziz, Dyana; Winslow, David; Carter, Rickey E.; Swearingen, Joshua E.; Buhusi, Mona C.

2010-01-01

In many species, interval timing behavior is accurate—appropriate estimated durations—and scalar—errors vary linearly with estimated durations. While accuracy has been previously examined, scalar timing has not been yet clearly demonstrated in house mice (Mus musculus), raising concerns about mouse models of human disease. We estimated timing accuracy and precision in C57BL/6 mice, the most used background strain for genetic models of human disease, in a peak-interval procedure with multiple intervals. Both when timing two intervals (Experiment 1) or three intervals (Experiment 2), C57BL/6 mice demonstrated varying degrees of timing accuracy. Importantly, both at individual and group level, their precision varied linearly with the subjective estimated duration. Further evidence for scalar timing was obtained using an intraclass correlation statistic. This is the first report of consistent, reliable scalar timing in a sizable sample of house mice, thus validating the PI procedure as a valuable technique, the intraclass correlation statistic as a powerful test of the scalar property, and the C57BL/6 strain as a suitable background for behavioral investigations of genetically engineered mice modeling disorders of interval timing. PMID:19824777

Notes on testing equality and interval estimation in Poisson frequency data under a three-treatment three-period crossover trial.

PubMed

Lui, Kung-Jong; Chang, Kuang-Chao

2016-10-01

When the frequency of event occurrences follows a Poisson distribution, we develop procedures for testing equality of treatments and interval estimators for the ratio of mean frequencies between treatments under a three-treatment three-period crossover design. Using Monte Carlo simulations, we evaluate the performance of these test procedures and interval estimators in various situations. We note that all test procedures developed here can perform well with respect to Type I error even when the number of patients per group is moderate. We further note that the two weighted-least-squares (WLS) test procedures derived here are generally preferable to the other two commonly used test procedures in the contingency table analysis. We also demonstrate that both interval estimators based on the WLS method and interval estimators based on Mantel-Haenszel (MH) approach can perform well, and are essentially of equal precision with respect to the average length. We use a double-blind randomized three-treatment three-period crossover trial comparing salbutamol and salmeterol with a placebo with respect to the number of exacerbations of asthma to illustrate the use of these test procedures and estimators. © The Author(s) 2014.

[Estimation of the time of death based on the measurements of the eye temperature in comparison with other body sites].

PubMed

Kaliszan, Michał; Hauser, Roman

2007-01-01

A systematic two-stage study was conducted in pigs to verify the models of postmortem body temperature decrease currently employed in forensic medicine. During the investigations, temperature recordings were performed in four body sites (eyeballs, orbit soft tissues, muscles and rectums). The results of the study support the possible use of the eyeball and also the orbit soft tissues as temperature measuring sites at the early phase after death; they have narrowed the significance of rectum temperature measurements to the late stage of postmortem body temperature decrease, shown insignificant correlations between the body weight and the temperature decrease rate constant and illustrated the functional increase of the time of death estimation error as the body cools, expressed in the distinct tendency to overestimate the calculated time of death as compared to the actual one. In the second stage of the experiment, a lack of a plateau phase was demonstrated, at least from 30 min post mortem. It was also found that in the very early post mortem period, the kinetics of cooling of all the body sites studied was better described by the two-exponential model than the single exponential one. The study also showed that the weak airflow present in the experimental conditions did not practically affect the course of cooling of the investigated body sites. Eyeball temperature measurements with an infra-red laser thermometer performed during the experiment proved to be of no use for determination of the time of death. The experiments allowed for defining the so far unreported value of physiological temperature of pig eyeball as 38 degrees C.

Identification of genes and gene pathways associated with major depressive disorder by integrative brain analysis of rat and human prefrontal cortex transcriptomes

PubMed Central

Malki, K; Pain, O; Tosto, M G; Du Rietz, E; Carboni, L; Schalkwyk, L C

2015-01-01

Despite moderate heritability estimates, progress in uncovering the molecular substrate underpinning major depressive disorder (MDD) has been slow. In this study, we used prefrontal cortex (PFC) gene expression from a genetic rat model of MDD to inform probe set prioritization in PFC in a human post-mortem study to uncover genes and gene pathways associated with MDD. Gene expression differences between Flinders sensitive (FSL) and Flinders resistant (FRL) rat lines were statistically evaluated using the RankProd, non-parametric algorithm. Top ranking probe sets in the rat study were subsequently used to prioritize orthologous selection in a human PFC in a case–control post-mortem study on MDD from the Stanley Brain Consortium. Candidate genes in the human post-mortem study were then tested against a matched control sample using the RankProd method. A total of 1767 probe sets were differentially expressed in the PFC between FSL and FRL rat lines at (q⩽0.001). A total of 898 orthologous probe sets was found on Affymetrix's HG-U95A chip used in the human study. Correcting for the number of multiple, non-independent tests, 20 probe sets were found to be significantly dysregulated between human cases and controls at q⩽0.05. These probe sets tagged the expression profile of 18 human genes (11 upregulated and seven downregulated). Using an integrative rat–human study, a number of convergent genes that may have a role in pathogenesis of MDD were uncovered. Eighty percent of these genes were functionally associated with a key stress response signalling cascade, involving NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells), AP-1 (activator protein 1) and ERK/MAPK, which has been systematically associated with MDD, neuroplasticity and neurogenesis. PMID:25734512

Variations in clinical presentation and anatomical distribution of gross lesions of African swine fever in domestic pigs in the southern highlands of Tanzania: a field experience.

PubMed

Kipanyula, Maulilio John; Nong'ona, Solomon Wilson

2017-02-01

African swine fever is a contagious viral disease responsible for up to 100% mortality among domestic pigs. A longitudinal study was carried out to determine the clinical presentation and anatomical distribution of gross lesions in affected pigs in Mbeya region, Tanzania during the 2010 to 2014 outbreaks. Data were collected during clinical and postmortem examination by field veterinarians and using a structured questionnaire. A total of 118 respondents (100%) showed awareness about African swine fever. During previous outbreaks, the mortality rate was almost 100%, while in 2014 it was estimated to be less than 50%.The clinical picture of the 2010-2012 outbreaks was characterized by high fever, depression, inappetance, mucosal congestion, hemorrhages, erythematous lesions in different body parts, and abortion. Several internal organs including the kidneys, spleen, and liver were congested and edematous. During the 2014 outbreak, a number of pigs (49.7%) were asymptomatic when brought to slaughter slabs but were found to have African swine fever gross lesions at postmortem examination as compared to 12.3% in 2010-2012. Bluish discoloration, which is normally distributed on the non-hairy parts of the body, was not apparent in some pigs except at postmortem examination. Some pigs (36.1%) presented nasal and/or oral bloody discharges which were uncommon (9.1%) during previous outbreaks. Moreover, other gross features included enlarged dark red renal lymph nodes and spleen. Clinical signs such as anorexia, diarrhea, and pyrexia were mainly observed when affected pigs reached moribund stage. The majority of pregnant sows died without presenting abortions. In some litters, suckling piglets (3-6 weeks) survived from the disease. These findings indicated that in 2014, African swine fever outbreak in Mbeya region was characterized by a different clinical picture.

Functional and Structural Succession of Soil Microbial Communities below Decomposing Human Cadavers

PubMed Central

Cobaugh, Kelly L.; Schaeffer, Sean M.; DeBruyn, Jennifer M.

2015-01-01

The ecological succession of microbes during cadaver decomposition has garnered interest in both basic and applied research contexts (e.g. community assembly and dynamics; forensic indicator of time since death). Yet current understanding of microbial ecology during decomposition is almost entirely based on plant litter. We know very little about microbes recycling carcass-derived organic matter despite the unique decomposition processes. Our objective was to quantify the taxonomic and functional succession of microbial populations in soils below decomposing cadavers, testing the hypotheses that a) periods of increased activity during decomposition are associated with particular taxa; and b) human-associated taxa are introduced to soils, but do not persist outside their host. We collected soils from beneath four cadavers throughout decomposition, and analyzed soil chemistry, microbial activity and bacterial community structure. As expected, decomposition resulted in pulses of soil C and nutrients (particularly ammonia) and stimulated microbial activity. There was no change in total bacterial abundances, however we observed distinct changes in both function and community composition. During active decay (7 - 12 days postmortem), respiration and biomass production rates were high: the community was dominated by Proteobacteria (increased from 15.0 to 26.1% relative abundance) and Firmicutes (increased from 1.0 to 29.0%), with reduced Acidobacteria abundances (decreased from 30.4 to 9.8%). Once decay rates slowed (10 - 23 d postmortem), respiration was elevated, but biomass production rates dropped dramatically; this community with low growth efficiency was dominated by Firmicutes (increased to 50.9%) and other anaerobic taxa. Human-associated bacteria, including the obligately anaerobic Bacteroides, were detected at high concentrations in soil throughout decomposition, up to 198 d postmortem. Our results revealed the pattern of functional and compositional succession in soil microbial communities during decomposition of human-derived organic matter, provided insight into decomposition processes, and identified putative predictor populations for time since death estimation. PMID:26067226

Adult carrion arthropod community in a tropical rainforest of Malaysia: analysis on three common forensic entomology animal models.

PubMed

Azwandi, A; Nina Keterina, H; Owen, L C; Nurizzati, M D; Omar, B

2013-09-01

Decomposing carrion provides a temporary microhabitat and food source for a distinct community of organisms. Arthropods constitute a major part of this community and can be utilized to estimate the postmortem interval (PMI) of cadavers during criminal investigations. However, in Malaysia, knowledge of carrion arthropod assemblages and their succession is superficial. Therefore, a study on three types of forensic entomology animal model was conducted from 27 September 2010 to 28 October 2010 in a tropical rainforest at National University of Malaysia, Bangi, Selangor, Malaysia. Over one month collections of arthropods were made on nine animal carcasses: three laboratory rats (Rattus norvegicus, mean weight: 0.508 ± 0.027 kg), three rabbits (Oryctolagus cuniculus, mean weight: 2.538 ± 0.109 kg) and three long tailed macaque (Macaca fascicularis, mean weight: 5.750 ± 0.551 kg). A total of 31,433 arthropods belonging to eight orders and twenty-eight families were collected from all carcasses. Among 2924 of adults flies collected, approximately 19% were calliphorids with Chrysomya megacephala (Fabricius, 1794) being the most abundant. Arthropod taxon richness was lower on rat carcasses compared to that of rabbit and monkey carcasses, and this was more apparent during the first week of decomposition. However, there were no significant differences in Shannon-Weiner index (H'), Simpson dominance index (C) and Pielou's Evenness index (J) between different animal model. The arthropod assemblages associated to animal model were different significantly (p<0.05) while decomposition stage was a significant factor influencing insect assemblages (p<0.05). Analysis on the arthropods succession indicated that some taxa have a clear visitation period while the others, particularly Coleoptera, did not show a clear successional pattern thus require futher insect succession study. Although human bodies were not possible for the succession study, most of the arthropods collected are necrophagous, and will also possibly colonize human cadaver, and potentially be useful in assisting in estimates of PMI in future forensic cases in Malaysia.

Moisture can be the dominant environmental parameter governing cadaver decomposition in soil.

PubMed

Carter, David O; Yellowlees, David; Tibbett, Mark

2010-07-15

Forensic taphonomy involves the use of decomposition to estimate postmortem interval (PMI) or locate clandestine graves. Yet, cadaver decomposition remains poorly understood, particularly following burial in soil. Presently, we do not know how most edaphic and environmental parameters, including soil moisture, influence the breakdown of cadavers following burial and alter the processes that are used to estimate PMI and locate clandestine graves. To address this, we buried juvenile rat (Rattus rattus) cadavers (approximately 18 g wet weight) in three contrasting soils from tropical savanna ecosystems located in Pallarenda (sand), Wambiana (medium clay), or Yabulu (loamy sand), Queensland, Australia. These soils were sieved (2mm), weighed (500 g dry weight), calibrated to a matric potential of -0.01 megapascals (MPa), -0.05 MPa, or -0.3 MPa (wettest to driest) and incubated at 22 degrees C. Measurements of cadaver decomposition included cadaver mass loss, carbon dioxide-carbon (CO(2)-C) evolution, microbial biomass carbon (MBC), protease activity, phosphodiesterase activity, ninhydrin-reactive nitrogen (NRN) and soil pH. Cadaver burial resulted in a significant increase in CO(2)-C evolution, MBC, enzyme activities, NRN and soil pH. Cadaver decomposition in loamy sand and sandy soil was greater at lower matric potentials (wetter soil). However, optimal matric potential for cadaver decomposition in medium clay was exceeded, which resulted in a slower rate of cadaver decomposition in the wettest soil. Slower cadaver decomposition was also observed at high matric potential (-0.3 MPa). Furthermore, wet sandy soil was associated with greater cadaver decomposition than wet fine-textured soil. We conclude that gravesoil moisture content can modify the relationship between temperature and cadaver decomposition and that soil microorganisms can play a significant role in cadaver breakdown. We also conclude that soil NRN is a more reliable indicator of gravesoil than soil pH. (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Novel method for the determination of Sildenafil (Viagra) and its metabolite (UK-103,320) in postmortem specimens using LC/MS/MS and LC/MS/MS/MS.

DOT National Transportation Integrated Search

2000-05-01

During the investigation of aviation accidents, postmortem samples from victims are submitted to the FAAs : Civil Aeromedical Institute for drug analysis. Because new drugs are continually being released to the market, it : is our laboratorys r...

Relationship between Raw Breast Meat Color Lightness Values and Functionalities or Broiler Fillets Deboned Six to Eight Hours Postmortem

USDA-ARS?s Scientific Manuscript database

Relationship between Raw Breast Meat Color Lightness Values and Functionalities of Broiler Fillets Deboned Six to Eight Hours Postmortem H. Zhuang and E. M. Savage Quality Assessment Research Unit, USDA, Agricultural Research Service, Russell Research Center, P. O. Box 5677, Athens, Georgia 30604-56...

Effect of three postmortem electrical stimulation treatments on the quality of early-deboned broiler breast meat

USDA-ARS?s Scientific Manuscript database

Electrical stimulation (ES) of animal carcasses during postmortem has been commonly used by beef industry to enhance meat tenderness, and has been recently adapted for commercial use with poultry. Majority of published investigations of ES effects on the tenderness of early-deboned poultry breast m...

CE-TOF MS-based metabolomic profiling revealed characteristic metabolic pathways in postmortem porcine fast and slow type muscles.

PubMed

Muroya, Susumu; Oe, Mika; Nakajima, Ikuyo; Ojima, Koichi; Chikuni, Koichi

2014-12-01

To determine key compounds and metabolic pathways associated with meat quality, we profiled metabolites in postmortem porcine longissimus lumborum (LL) and vastus intermedius (VI) muscles with different aging times by global metabolomics using capillary electrophoresis-time of flight mass spectrometry. Loading analyses of the principal component analysis showed that hydrophilic amino acids and β-alanine-related compounds contributed to the muscle type positively and negatively, respectively, whereas glycolytic and ATP degradation products contributed to aging time. At 168h postmortem, LL samples were characterized by abundance of combinations of amino acids, dipeptides, and glycolytic products, whereas the VI samples were characterized by abundance of both sulfur-containing compounds and amino acids. The AMP and inosine contents in the VI were approx. 10 times higher than those in the LL at 4h postmortem, suggesting different rates of inosine 5'-monophosphate (IMP) accumulation by adenylate kinase 7 and 5'-nucleotidase, and subsequent different production levels of IMP and hypoxanthine between these two porcine muscles. Copyright © 2014 Elsevier Ltd. All rights reserved.

Interpretation of postmortem forensic toxicology results for injury prevention research.

PubMed

Drummer, Olaf H; Kennedy, Briohny; Bugeja, Lyndal; Ibrahim, Joseph Elias; Ozanne-Smith, Joan

2013-08-01

Forensic toxicological data provides valuable insight into the potential contribution of alcohol and drugs to external-cause deaths. There is a paucity of material that guides injury researchers on the principles that need to be considered when examining the presence and contribution of alcohol and drugs to these deaths. This paper aims to describe and discuss strengths and limitations of postmortem forensic toxicology sample selection, variations in analytical capabilities and data interpretation for injury prevention research. Issues to be considered by injury researchers include: the circumstances surrounding death (including the medical and drug use history of the deceased person); time and relevant historical factors; postmortem changes (including redistribution and instability); laboratory practices; specimens used; drug concentration; and attribution of contribution to death. This paper describes the range of considerations for testing and interpreting postmortem forensic toxicology, particularly when determining impairment or toxicity as possible causal factors in injury deaths. By describing these considerations, this paper has application to decisions about study design and case inclusion in injury prevention research, and to the interpretation of research findings.

On the appropriateness of applying chi-square distribution based confidence intervals to spectral estimates of helicopter flyover data

NASA Technical Reports Server (NTRS)

Rutledge, Charles K.

1988-01-01

The validity of applying chi-square based confidence intervals to far-field acoustic flyover spectral estimates was investigated. Simulated data, using a Kendall series and experimental acoustic data from the NASA/McDonnell Douglas 500E acoustics test, were analyzed. Statistical significance tests to determine the equality of distributions of the simulated and experimental data relative to theoretical chi-square distributions were performed. Bias and uncertainty errors associated with the spectral estimates were easily identified from the data sets. A model relating the uncertainty and bias errors to the estimates resulted, which aided in determining the appropriateness of the chi-square distribution based confidence intervals. Such confidence intervals were appropriate for nontonally associated frequencies of the experimental data but were inappropriate for tonally associated estimate distributions. The appropriateness at the tonally associated frequencies was indicated by the presence of bias error and noncomformity of the distributions to the theoretical chi-square distribution. A technique for determining appropriate confidence intervals at the tonally associated frequencies was suggested.

Partial-Interval Estimation of Count: Uncorrected and Poisson-Corrected Error Levels

ERIC Educational Resources Information Center

Yoder, Paul J.; Ledford, Jennifer R.; Harbison, Amy L.; Tapp, Jon T.

2018-01-01

A simulation study that used 3,000 computer-generated event streams with known behavior rates, interval durations, and session durations was conducted to test whether the main and interaction effects of true rate and interval duration affect the error level of uncorrected and Poisson-transformed (i.e., "corrected") count as estimated by…

Confidence Intervals for Effect Sizes: Applying Bootstrap Resampling

ERIC Educational Resources Information Center

Banjanovic, Erin S.; Osborne, Jason W.

2016-01-01

Confidence intervals for effect sizes (CIES) provide readers with an estimate of the strength of a reported statistic as well as the relative precision of the point estimate. These statistics offer more information and context than null hypothesis statistic testing. Although confidence intervals have been recommended by scholars for many years,…

Updated estimates of HAL n and RN- effects on pork quality: fresh and processed loin and ham.

PubMed

Cherel, P; Glénisson, J; Figwer, P; Pires, J; Damon, M; Franck, M; Le Roy, P

2010-12-01

A 1000-pig F2 intercross QTL detection experimental population was generated using two commercial sire lines. Independent carriers of HAL n and RN- mutations (10% and 14%, respectively) were included in this population as control genotypes. The effects of HAL n and RN- heterozygous genotypes on fresh and transformed loins and hams were estimated using a mixed model methodology. The results document the unfavorable effects of both mutations on meat quality. Smaller effects of HAL Nn genotype compared to HAL nn or RN-rn+ genotypes were estimated. Interestingly, effects of HAL Nn genotype on meat pH and loin color could be insignificant at 24-h postmortem, but translate into higher water losses on storage and cooking, and result in tougher cooked loin. Using the same methodology, significant effects of the PRKAG3 (RN) I199 allele on ultimate pH values but not on glycolytic potential were observed. Copyright © 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.

Rigor mortis development at elevated temperatures induces pale exudative turkey meat characteristics.

PubMed

McKee, S R; Sams, A R

1998-01-01

Development of rigor mortis at elevated post-mortem temperatures may contribute to turkey meat characteristics that are similar to those found in pale, soft, exudative pork. To evaluate this effect, 36 Nicholas tom turkeys were processed at 19 wk of age and placed in water at 40, 20, and 0 C immediately after evisceration. Pectoralis muscle samples were taken at 15 min, 30 min, 1 h, 2 h, and 4 h post-mortem and analyzed for R-value (an indirect measure of adenosine triphosphate), glycogen, pH, color, and sarcomere length. At 4 h, the remaining intact Pectoralis muscle was harvested, and aged on ice 23 h, and analyzed for drip loss, cook loss, shear values, and sarcomere length. By 15 min post-mortem, the 40 C treatment had higher R-values, which persisted through 4 h. By 1 h, the 40 C treatment pH and glycogen levels were lower than the 0 C treatment; however, they did not differ from those of the 20 C treatment. Increased L* values indicated that color became more pale by 2 h post-mortem in the 40 C treatment when compared to the 20 and 0 C treatments. Drip loss, cook loss, and shear value were increased whereas sarcomere lengths were decreased as a result of the 40 C treatment. These findings suggested that elevated post-mortem temperatures during processing resulted in acceleration of rigor mortis and biochemical changes in the muscle that produced pale, exudative meat characteristics in turkey.

Attitudes Concerning Postmortem Organ Donation: A Multicenter Survey in Various German Cohorts.

PubMed

Uhlig, Constantin E; Böhringer, Daniel; Hirschfeld, Gerrit; Seitz, Berthold; Schmidt, Hartmut

2015-10-13

The aim of this study was to characterize postmortem organ donation attitudes in various German cohorts. Employees of 2 German cities and 2 German university hospitals, employees of a German automobile enterprise, and members of a German Medical Society were administered a questionnaire about postmortem organ and tissue donation attitudes. Demographic data and general attitudes were questioned and focused on: I) willingness to donate organs, II) holding a donor card, and III) having discussed the topic with the family. Of 5291 participants, 65.2% reported favoring postmortem organ donation. Missing negative experiences, the idea that donation is helpful, a non-medical professional environment, excellent general health, gender, agreement with the brain-death paradigm, and age significantly influenced the participants' attitudes. Participants were more likely to possess donor cards and had discussed more often with family members if they agreed with the brain-death paradigm and considered donation to be helpful. Males and older participants were the most likely to neglect donor cards, and Catholics, Protestants, and participants with poor health were the least likely to donate organs. Interest in receiving more information was expressed by 38.1% and 50.6% of participants refusing donation of all or of specific organs, respectively, and suggested the internet (60.0%) and family doctors (35.0%) as preferred sources of information. Public campaigns in Germany should focus on males and older people as regards donor cards, and females, younger, and religiously affiliated persons as regards the general willingness to donate organs postmortem.

Impact of heart disease and calibration interval on accuracy of pulse transit time-based blood pressure estimation.

PubMed

Ding, Xiaorong; Zhang, Yuanting; Tsang, Hon Ki

2016-02-01

Continuous blood pressure (BP) measurement without a cuff is advantageous for the early detection and prevention of hypertension. The pulse transit time (PTT) method has proven to be promising for continuous cuffless BP measurement. However, the problem of accuracy is one of the most challenging aspects before the large-scale clinical application of this method. Since PTT-based BP estimation relies primarily on the relationship between PTT and BP under certain assumptions, estimation accuracy will be affected by cardiovascular disorders that impair this relationship and by the calibration frequency, which may violate these assumptions. This study sought to examine the impact of heart disease and the calibration interval on the accuracy of PTT-based BP estimation. The accuracy of a PTT-BP algorithm was investigated in 37 healthy subjects and 48 patients with heart disease at different calibration intervals, namely 15 min, 2 weeks, and 1 month after initial calibration. The results showed that the overall accuracy of systolic BP estimation was significantly lower in subjects with heart disease than in healthy subjects, but diastolic BP estimation was more accurate in patients than in healthy subjects. The accuracy of systolic and diastolic BP estimation becomes less reliable with longer calibration intervals. These findings demonstrate that both heart disease and the calibration interval can influence the accuracy of PTT-based BP estimation and should be taken into consideration to improve estimation accuracy.

Estimation of sojourn time in chronic disease screening without data on interval cases.

PubMed

Chen, T H; Kuo, H S; Yen, M F; Lai, M S; Tabar, L; Duffy, S W

2000-03-01

Estimation of the sojourn time on the preclinical detectable period in disease screening or transition rates for the natural history of chronic disease usually rely on interval cases (diagnosed between screens). However, to ascertain such cases might be difficult in developing countries due to incomplete registration systems and difficulties in follow-up. To overcome this problem, we propose three Markov models to estimate parameters without using interval cases. A three-state Markov model, a five-state Markov model related to regional lymph node spread, and a five-state Markov model pertaining to tumor size are applied to data on breast cancer screening in female relatives of breast cancer cases in Taiwan. Results based on a three-state Markov model give mean sojourn time (MST) 1.90 (95% CI: 1.18-4.86) years for this high-risk group. Validation of these models on the basis of data on breast cancer screening in the age groups 50-59 and 60-69 years from the Swedish Two-County Trial shows the estimates from a three-state Markov model that does not use interval cases are very close to those from previous Markov models taking interval cancers into account. For the five-state Markov model, a reparameterized procedure using auxiliary information on clinically detected cancers is performed to estimate relevant parameters. A good fit of internal and external validation demonstrates the feasibility of using these models to estimate parameters that have previously required interval cancers. This method can be applied to other screening data in which there are no data on interval cases.

Interpretation of Flow Logs from Nevada Test Site Boreholes to Estimate Hydraulic Conductivity Using Numerical Simulations Constrained by Single-Well Aquifer Tests

USGS Publications Warehouse

Garcia, C. Amanda; Halford, Keith J.; Laczniak, Randell J.

2010-01-01

Hydraulic conductivities of volcanic and carbonate lithologic units at the Nevada Test Site were estimated from flow logs and aquifer-test data. Borehole flow and drawdown were integrated and interpreted using a radial, axisymmetric flow model, AnalyzeHOLE. This integrated approach is used because complex well completions and heterogeneous aquifers and confining units produce vertical flow in the annular space and aquifers adjacent to the wellbore. AnalyzeHOLE simulates vertical flow, in addition to horizontal flow, which accounts for converging flow toward screen ends and diverging flow toward transmissive intervals. Simulated aquifers and confining units uniformly are subdivided by depth into intervals in which the hydraulic conductivity is estimated with the Parameter ESTimation (PEST) software. Between 50 and 150 hydraulic-conductivity parameters were estimated by minimizing weighted differences between simulated and measured flow and drawdown. Transmissivity estimates from single-well or multiple-well aquifer tests were used to constrain estimates of hydraulic conductivity. The distribution of hydraulic conductivity within each lithology had a minimum variance because estimates were constrained with Tikhonov regularization. AnalyzeHOLE simulated hydraulic-conductivity estimates for lithologic units across screened and cased intervals are as much as 100 times less than those estimated using proportional flow-log analyses applied across screened intervals only. Smaller estimates of hydraulic conductivity for individual lithologic units are simulated because sections of the unit behind cased intervals of the wellbore are not assumed to be impermeable, and therefore, can contribute flow to the wellbore. Simulated hydraulic-conductivity estimates vary by more than three orders of magnitude across a lithologic unit, indicating a high degree of heterogeneity in volcanic and carbonate-rock units. The higher water transmitting potential of carbonate-rock units relative to volcanic-rock units is exemplified by the large difference in their estimated maximum hydraulic conductivity; 4,000 and 400 feet per day, respectively. Simulated minimum estimates of hydraulic conductivity are inexact and represent the lower detection limit of the method. Minimum thicknesses of lithologic intervals also were defined for comparing AnalyzeHOLE results to hydraulic properties in regional ground-water flow models.

Understanding Early Post-Mortem Biochemical Processes Underlying Meat Color and pH Decline in the Longissimus thoracis Muscle of Young Blond d'Aquitaine Bulls Using Protein Biomarkers.

PubMed

Gagaoua, Mohammed; Terlouw, E M Claudia; Micol, Didier; Boudjellal, Abdelghani; Hocquette, Jean-François; Picard, Brigitte

2015-08-05

Many studies on color biochemistry and protein biomarkers were undertaken in post-mortem beef muscles after ≥24 hours. The present study was conducted on Longissimus thoracis muscles of 21 Blond d'Aquitaine young bulls to evaluate the relationships between protein biomarkers present during the early post-mortem and known to be related to tenderness and pH decline and color development. pH values at 45 min, 3 h, and 30 h post-mortem were correlated with three, seven, and six biomarkers, respectively. L*a*b* color coordinates 24 h post-mortem were correlated with nine, five, and eight protein biomarkers, respectively. Regression models included Hsp proteins and explained between 47 and 59% of the variability between individuals in pH and between 47 and 65% of the variability in L*a*b* color coordinates. Proteins correlated with pH and/or color coordinates were involved in apoptosis or had antioxidative or chaperone activities. The main results include the negative correlations between pH45 min, pH3 h, and pHu and Prdx6, which may be explained by the antioxidative and phospholipase activities of this biomarker. Similarly, inducible Hsp70-1A/B and μ-calpain were correlated with L*a*b* coordinates, due to the protective action of Hsp70-1A/B on the proteolytic activities of μ-calpain on structural proteins. Correlations existed further between MDH1, ENO3, and LDH-B and pH decline and color stability probably due to the involvement of these enzymes in the glycolytic pathway and, thus, the energy status of the cell. The present results show that research using protein indicators may increase the understanding of early post-mortem biological mechanisms involved in pH and beef color development.

Postmortem Fluid and Tissue Concentrations of THC, 11-OH-THC and THC-COOH.

PubMed

Saenz, Sunday R; Lewis, Russell J; Angier, Mike K; Wagner, Jarrad R

2017-07-01

Marijuana is the most commonly abused illicit drug worldwide. Marijuana is used for its euphoric and relaxing properties. However, marijuana use has been shown to result in impaired memory, cognitive skills and psychomotor function. The Federal Aviation Administration's Civil Aerospace Medical Institute conducts toxicological analysis on aviation fatalities. Due to severe trauma associated with aviation accidents, blood is not always available; therefore, the laboratory must rely on specimens other than blood for toxicological analysis in ~30-40% of cases. However, the postmortem distribution of cannabinoids has not been well characterized. The purpose of this research is to evaluate the distribution of Δ9-tetrahydrocannabinol (THC), and its metabolites, 11-hydroxy-tetrahydrocannabinol (11-OH-THC) and THC-COOH, in postmortem fluid and tissue specimens from 11 fatal aviation accident cases (2014-2015) previously found positive for cannabinoids. Specimens evaluated, when available, included: blood, urine, vitreous humor, liver, lung, kidney, spleen, muscle, brain, heart and bile. We developed and validated (following SWGTOX guidelines) a sensitive and robust method using solid-phase extraction and liquid chromatography-tandem mass spectrometry to identify and quantify THC, 11-OH-THC and THC-COOH in postmortem fluids and tissues. The method readily identified and quantified these cannabinoids in postmortem fluids and tissues below 1 ng/mL. Qualitative cannabinoid results within each case were comparable between blood and non-blood specimens. However, there was no consistent distribution of the cannabinoids between blood and any other fluids or tissues. Therefore, while quantitative interpretation of non-blood postmortem fluid and tissues samples is not prudent, a majority of the non-blood specimens tested could be suitable alternative/supplemental choices for qualitative cannabinoid detection. Published by Oxford University Press 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Clinical information has low sensitivity for postmortem diagnosis of heart valve disease.

PubMed

Coffey, Sean; Harper, Andrew R; Cairns, Benjamin J; Roberts, Ian Sd; Prendergast, Bernard D

2017-07-01

Accuracy of routinely collected information concerning cause of death is essential for public health and health systems planning. Since clinical examination has relatively low sensitivity for detection of valvular heart disease (VHD), mortality data based on clinical information alone might routinely underestimate the number of deaths due to VHD. We compared autopsy findings against premortem clinical information for 8198 consecutive adult postmortems (mean age 69.1 years, 61.3% men), performed in a single UK tertiary referral centre with on-site cardiac surgical facilities over a 10-year period (2004-2013) during which 21% of the adult population underwent postmortem examination. Following postmortem, VHD was the principal cause of death in 165 individuals (2.0%), a principal or contributory cause ('any cause') of death in 326 (4.0%) and an incidental (ie, non-causal) finding in a further 346 (4.2%). Clinical documentation of VHD before death was highly specific but relatively insensitive for postmortem identification of VHD as the principal (specificity 96.8%; 95% CI 96.4% to 97.2%; sensitivity 69.7%, 95% CI 62.1% to 76.6%) or any (specificity 98.1%; 95% CI 97.8% to 98.4%; sensitivity 68.4%, 95% CI 63.1% to 73.4%) cause of death. VHD (principally aortic stenosis, endocarditis and rheumatic heart disease) was newly noted at postmortem and listed as a cause of death in 142 individuals (1.7%). Clinical information recorded premortem is highly specific but relatively insensitive for the cause of death established at autopsy. Population-based mortality statistics that depend on premortem clinical information are likely to routinely underestimate the mortality burden of VHD. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Feather retention force in broilers ante-, peri-, and post-mortem as influenced by electrical and carbon dioxide stunning.

PubMed

Buhr, R J; Cason, J A; Rowland, G N

1997-11-01

Stunning and slaughter trials were conducted to evaluate the influence of stunning method (electrical 50 V alternating current, CO2 gas: 0 to 40% for 90 s or 40 to 60% for 30 s) on feather retention force (FRF) in commercial broilers. Feathers from the pectoral, sternal, and femoral feather tracts were sampled with a force gauge before stunning (ante-mortem) and contralaterally either after stunning (peri-mortem from 0.5 to 4 min) or after stunning and bleeding (post-mortem from 2 to 6 min). Prior to stunning, ante-mortem FRF values varied among assigned stunning methods only for the pectoral (7%) feather tract. After stunning, peri-mortem FRF values were higher only for the sternal tract (11% for 40 to 60% CO2 for 30 s); whereas after stunning and bleeding, post-mortem FRF values were lower than ante- or peri-mortem only for the sternal tract (10% lower for 40 to 60% CO2 for 30 s). Peri- and post-mortem FRF values did not differ among stunning methods for the pectoral and femoral feather tracts. Small changes in FRF values occurred from ante-mortem to peri-mortem (-1 to +12%), and from ante-mortem to post-mortem (-2 to +8%) across stunning methods. A significant increase was determined for only the pectoral tract (7%) from ante- to peri-mortem across stunning methods. Electrically stunned broilers that were not bled gained weight in excess of the 36 feathers removed (0.16%), apparently due to body surface water pickup during the brine-stunning process, whereas CO2-stunned broilers lost weight due to excretion of cloacal contents (-0.31 to -0.98%). The change in body weight among stunning methods was significant (P < 0.0233). Peri- and post-mortem FRF, in addition to bleed-out body weight loss, were not substantially influenced by electrical or CO2 stunning methods, and, therefore, carcass defeathering efficiency may not differ after scalding.

Postmortem brain MRI with selective tissue biopsy as an adjunct to autopsy following neonatal encephalopathy.

PubMed

Nicholl, R M; Balasubramaniam, V P; Urquhart, D S; Sellathurai, N; Rutherford, M A

2007-05-01

Following the death of a neonate it is essential that parents are given full and accurate information about the probable cause of death. Perinatal autopsy often adds new information or may even change the presumed diagnosis [Cartlidge PH, Dawson AT, Stewart JH, Vujanic GM. Value and quality of perinatal and infant postmortem examinations: cohort analysis of 400 consecutive deaths. Br Med J 1995;310(6973):155-8; Khong TY. Falling neonatal autopsy rates. Br Med J 2002;324(7340):749-50] informing decisions regarding the management of any future pregnancy. Autopsy can be considered the "gold standard" for the identification of antecedent events leading to a neonatal death. However, recent events in the UK have added to an already declining rate in neonatal autopsies [Brodlie M, Laing IA. Ten years of neonatal autopsies in tertiary referral centre: retrospective study. Br Med J 2002;324(7340):761-3]. To try and redress this balance the Chief Medical Officer has recommended that research should be commissioned into the use of non-invasive imaging to provide a similar standard of information [The Chief Medical Officer. The removal, retention and use of human organs and tissues from post mortem examination. London, England: The Stationary Office, Department of Health; 2001]. Previous publications on postmortem MRI have focused largely on investigation of the foetus and of still birth [Griffiths PD, Variend D, Evans M, Jones A, Wilkinson ID, Paley MNJ, et al. Postmortem MR imaging of the fetal and stillborn central nervous system. Am J Neuroradiol 2003;24(1):22-7; Whitby EH, Paley MN, Cohen M, GriffithsPD. Postmortem MR imaging of the fetus: an adjunct or a replacement for conventional autopsy? Semin Fetal Neonatal Med 2005;10(5):475-83]. We report our experience on the use of postmortem brain MRI combined with selective tissue biopsy, in six neonatal deaths in the setting of a large district general hospital.

The multi-factorial origins of Chronic Traumatic Encephalopathy (CTE) symptomology in post-career athletes: The athlete post-career adjustment (AP-CA) model.

PubMed

Gaetz, Michael

2017-05-01

CTE has two prominent components: the pathophysiology that is detected in the brain postmortem and the symptomology that is present in the interval between retirement and end of life. CTE symptomology has been noted to include memory difficulties, aggression, depression, explosivity, and executive dysfunction at early stages progressing to problems with attention, mood swings, visuospatial difficulties, confusion, progressive dementia, and suicidality (e.g. McKee et al. (2012), Omalu et al. (2010a-c), McKee et al. (2009)). There are a number of assumptions embedded within the current CTE literature: The first is the assumption that CTE symptomology reported by athletes and their families is the product of the pathophysiology change detected post-mortem (e.g. McKee et al. (2009)). At present, there is little scientific evidence to suggest that all CTE symptomology is the product of CTE pathophysiology. It has been assumed that CTE pathophysiology causes CTE symptomology (Meehan et al. (2015), Iverson et al. (2016)) but this link has never been scientifically validated. The purpose of the present work is to provide a multi-factorial theoretical framework to account for the symptomology reported by some athletes who sustain neurotrauma during their careers that will lead to a more systematic approach to understanding post-career symptomology. There is significant overlap between the case reports of athletes with post-mortem diagnoses of CTE, and symptom profiles of those with a history of substance use, chronic pain, and athlete career transition stress. The athlete post-career adjustment (AP-CA) model is intended to explain some of the symptoms that athletes experience at the end of their careers or during retirement. The AP-CA model consists of four elements: neurotrauma, chronic pain, substance use, and career transition stress. Based on the existing literature, it is clear that any one of the four elements of the AP-CA model can account for a significant number of CTE symptoms. In addition, depression can be a chronic lifelong co-morbid condition that may be present prior to an athletic career, or may be developed secondary to any of the model elements as shown in Fig. 1. Notably, neurotrauma is a necessary, but not a sufficient condition, for the development of CTE symptomology. Copyright © 2017 Elsevier Ltd. All rights reserved.