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At least 19 recordsLinked to original sources

[Roentgen identification of unknown cadavers with advanced postmortem changes].

The postmortem changes in the bodies of two individuals were so advanced that the usual identification methods could not be applied; one had drowned and the other died by burning. Antemortem roentgenograms--up to 10 years old--and postmortem X-ray plates were compared and the bodies thus identified. This was possible because the skeleton shows individual, highly specific markers that do not change during life or after death.

Adult↗

[About postmortem changes in the pancreas].

Postmortem changes in the pancreas of 23 patients who had died of cardiovascular and tumor pathology were studied with light microscopy and histochemical methods. Pancreatic tissue was obtained within 1, 2, 4, 6, 12, 24 hours after biological death. General features of postmortem changes were established and also some special aspects relevant to intravital and terminal period were defined. The results of the examination allow to make the conclusion on possibility of postmortem studying of the pancreas on the material of early autopsies.

Humans↗

X-ray diffraction measurements of postmortem changes in the myofilament lattice of pork.

Postmortem changes in the lateral spacing between filaments of the longissimus muscle in pork were examined by small-angle x-ray diffraction. Samples that were fixed in glutaraldehyde as soon as they were collected showed a rapid decrease in filament spacing from 1 h to 3 h and then a further, slower decrease to 24 h. Samples that were examined immediately or were kept prior to examination in buffered Ringer's solutions at pH values similar to those expected in the carcass showed a rapid decrease in filament spacing from 1 h to 3 h and then little further change to 24 h. In contrast, samples taken at various times postmortem and stored in Ringer's solutions at pH 7.2 for several hours before examination showed little postmortem change in lattice spacing. Fixed samples showed similar changes to those of unfixed samples, but the lattice spacing always was less in fixed than in unfixed samples. These results support the classic theory that much of the water that may be lost by drip and evaporation from meat originates from the spaces between the filaments. The major factor that caused shrinkage of the filament lattice and loss of water from the fibrils was pH.

Actin Cytoskeleton↗

An experimental methodology for the study of postmortem changes in toxic concentrations of drugs, using secobarbital as an example.

Postmortem changes in alcohol and drug concentrations are well known today. The authors used an HPLC assay of barbiturates in postmortem tissue, and developed a rat model in order to evidence postmortem changes in toxics concentrations. Postmortem changes in secobarbital concentrations were evidenced using a rat-secobarbital model. This work emphasizes the difficulty of postmortem toxicology, as concentrations found at the time of autopsy may be different from concentrations at the time of death.

Animals↗

Histology of postmortem changes in rat livers to ascertain hour of death.

Postmortem changes in hepatic tissues of male rats kept at 3 different temperatures after death (room temperature at 23 degrees C, body temperature at 37.5 degrees C, and cool temperature at 5 degrees C) were examined in relation to the hour of death. The time of occurrence and the degree of histological postmortem changes in the liver were found to differ depending on the temperature at which the body was kept (5 degrees C < 23 degrees C < 37.5 degrees C). There was a reduced stainability of erythrocytes, atrophy of hepatocytes, sinusoidal dilatation and karyopyknosis of endothelial or Kupffer cells, after 48 h at 5 degrees C. These observations were made after 3-5 h in tissues of rats kept at 37.5 degrees C, as compared to 12 h at 23 degrees C. Atrophy of hepatocytes and sinusoidal dilatation were prominent in the subcapsular region. In epithelia of the interlobular bile ducts (IBD), swelling of nuclei and karyopyknosis with an eosinophilic cytoplasm were evident. Electron microscopy revealed that the former change was heterogeneity of nucleoplasm and peripheral localization of nuclear chromatin with coagulative cytoplasmic organelles, and the latter was atrophy of nuclei with cytoplasm, including disruption and disappearance of organelles. The time course of these findings in dead rats kept at different temperatures suggests that postmortem changes of epithelial nuclei of IBD progressed from swelling to karyorrhexis (disappearance) via karyopyknosis. The frequency of karyopyknosis with an eosinophilic cytoplasm of IBD epithelia (positive cells) at 37.5 degrees C increased rapidly up to 5 h after death, and decreased extensively after 12 h. At 37.5 degrees C, the frequency of positive cells increased constantly up to 24 h, in accordance with hour of death. At 5 degrees C, the frequency of positive cells increased slowly up to 48 h, and the majority of epithelia showed positive changes at 72 h. The frequency of cells positive for karyopyknosis and eosinophilic cytoplasm can serve as one marker for estimating the hour of death.

Animals↗

Postmortem changes in brain catecholamine enzymes.

Postmortem changes in the activities of tyrosine hydroxylase, dopa decarboxylase, and dopamine-beta-hydroxylase were examined in various areas of rat brain. Tyrosine hydroxylase activity decreased in an exponential fashion with a half-time of two to four hours in caudate-putamen, substantia nigra, and locus ceruleus. Dopa decarboxylase activity remained within 20% of control values at five hours in these areas, but then decreased precipitously. Dopamine-beta-hydroxylase activity remained within 20% of control for at least 20 hours after death.

Animals↗

Experimental study of postmortem change under field conditions: effects of freezing, thawing, and mechanical injury.

Understanding the processes of postmortem change in biologic systems is important to the forensic sciences. Previous experimental studies of postmortem change in animals under field conditions made use of animal carcasses that had been incidentally exposed to the effects of freezing and thawing or mechanical damage, or both, and were limited to gross observations. The current study was designed to document intrinsic processes of postmortem change, and the effects of freezing-thawing and mechanical injury, under controlled conditions in the field, using histologic and microbiologic techniques, as well as gross observation. Insect and microbiologic succession sequences, and patterns of decomposition and disarticulation, were observable over time. Previously frozen-thawed animals showed predominantly decay (aerobic decomposition) in the field, while freshly killed animals showed predominantly putrefaction (anaerobic decomposition). Previously frozen animals showed the same sequence, but accelerated rates, of disarticulation. Mechanically injured tissues showed accelerated rates of decomposition. These findings have implications for the interpretation of results of previous studies, as well as the interpretation of human and animal remains subjected to freezing and thawing.

Animals↗

Pharmacokinetics and postmortem changes of cimetidine in body tissues.

Cimetidine concentrations in body tissues were pharmacokinetically examined, together with their postmortem changes, to assess the toxicological effect of this drug from the aspect of forensic medicine. For the pharmacokinetic study, rats were pithed at 0.5, 1.0, 2.0, 4.0 or 8.0 hours after an intravenous injection of the drug (33.3 mg/kg), and their tissue samples were immediately collected to be analyzed by high-performance liquid chromatography (HPLC). The concentrations of cimetidine in the blood and muscle decreased below the lower detection limit at 8 hours after the injection, while the drug could still be detected in the brain, lung, liver, kidney, spleen and adipose tissue. The ratios of the cimetidine concentrations in the muscle, lung and spleen to that in the blood were nearly constant until 4 hours after the injection, while those in the liver, kidney and adipose tissue increased as time elapsed. Postmortem changes of cimetidine concentrations were examined using the tissue samples collected 0, 1 and 2 days after death. There was no statistical significance in the postmortem changes in cimetidine concentrations in the body tissues over the two-day period of examination. The experimental results indicated that the muscle, lung and spleen together can serve as samples for toxicological analysis to evaluate the effect of cimetidine, regardless of various postmortem factors, including the availability of blood.

Animals↗

Ultrastructural postmortem changes in chicken kidneys at 27 C.

Ultrastructural postmortem changes of glomeruli, proximal tubules (PT), distal tubules (DT), and cortical collecting ducts (CD) were studied in adult chickens held at 27 C for 0, 1, 5, 10, 30, 60, or 360 minutes. There were marked ultrastructural alterations in tissues considered normal by light microscopy. The earliest changes, evident in immediately fixed samples, consisted of apical cell swelling of PT and DT epithelium and formation of smaller projections from glomerular capillary endothelium. Swelling increased with time, and gaps in cell membranes of tubular cytoplasmic blebs were evident by 10 minutes postmortem. The urinary space also contained cellular debris in immediately fixed samples and was filled by swollen epithelial cells by 10 minutes postmortem. Organelle changes were pronounced by 5 minutes in PT epithelium and by 10 minutes in DT epithelium. These initial changes consisted of dilation of mitochondrial and endoplasmic reticulum. Flocculent mitochondrial matrix densities were present by 5 minutes in PT epithelium and enlarged and appeared in other tubular segments as the time postmortem increased. Nuclear chromatin margination occurred first in 10-minute samples of PT and DT, and it was present by 30 minutes in glomerular epithelial cells. Chromatin clumping was present in PT and DT epithelium at 30 minutes and was followed by pyknosis and karyorrhexis at 360 minutes. These latter nuclear changes were not found in glomerular cells during the study. Nuclei of CD showed little change during the periods studied. The glomerular basement membrane appeared as a single hyaline membrane by 30 minutes postmortem, but this membrane and podocyte foot processes showed little further change by 360 minutes postmortem.

Animals↗

[Relationship between postmortem change and biological reaction].

In the adipocere which is one of postmortem changes, some specific fatty acids possessing higher melting points together with soap play an important role in the formation of adipocere. These fatty acids were clarified to be mainly 10-hydroxystearic and 10-hydroxypalmitic acids. Moreover, slight amounts of 10-oxostearic and 10-oxopalmitic acids, which have higher melting points than those of hydroxy fatty acids, exist in the adipocere as well. The substantial adipocere is formed and stabilized by these specific fatty acids together with the soap. The hydroxy fatty acid (OHFA) and oxo fatty acid (OXOFA) are biosynthesized by some enzymes from bacteria. Various aerobic and anaerobic bacteria are involved in the formation of adipocere. For example, microbial conversion of various unsaturated fatty acids to 10-OHFA by Micrococcus luteus was investigated. As a result, 10-OHFA was synthesized only from fatty acids possessing cis-9-unsaturation. It was also clarified that 10-OHFAs were converted to the corresponding 10-OXOFAs but the 10-OXO compounds were inactive as substrates. Furthermore, the enzyme preparations from Flavobacterium meningosepticum solubilized by sonication catalyzed not only hydration of oleic acid to produce 10-hydroxystearic acid but also dehydrogenation of this product in the presence of deuterium. On the other hand, we found out that there was 10-hydroxy-12-octadecenoic acid (10-OHLA) from linoleic acid in some kinds of adipocere. 10-OHFA existing in adipocere has been thought not to exist in a living body. However, recently 10-epoxy-12-octadecenoic acid (leukotoxin, LTx) which is one of lipid peroxides was found not only in rice plants but in polymorphonuclear leukocytes. It was also clarified that these polymorphonuclear leukocytes produced the same 10-OHLA as the compound found in adipocere. Since LTx was found from leukocytes related to inflammatory response, it has been interested in involvement of not only the basic mechanism of biological defense but also the mechanism of shock as a vasoactive substance. A postmortem change itself is little associated with a phenomenon on a living body. However, 10-OHLA found in adipocere existed also in polymorphonuclear leukocytes, suggesting that this compound metabolized from LTx is closely related to a biological reaction.

Adipose Tissue↗

Postmortem changes of triazolam concentrations in body tissues.

Postmortem changes of triazolam concentrations in body tissues were examined using rats, in order to find the most suitable tissue samples for toxicological analysis. Triazolam was orally given to rats (5 mg/kg), and then the rats were sacrificed 1 hour after administration. Tissue samples were collected 0, 1 and 2 days after storage at 22-24 degrees C, and the triazolam concentration in each sample was measured using gas chromatography with a nitrogen phosphorus detector. Triazolam concentrations were markedly increased in the spleen, the abdominal muscle, the liver and the kidney, and were slightly increased in the blood and the lung. On the other hand, no changes were observed in the thigh muscle or the brain, and the value in the thigh muscle was similar to those in the blood samples collected immediately after death. The results indicate that triazolam diffuses into the surrounding tissues through the stomach wall after death, so that the thigh muscle and the brain have to be analyzed as well as the blood for a correct diagnosis of triazolam ingestion.

Administration, Oral↗

Microscopic postmortem changes in adrenal glands of the domestic fowl.

Eighty-four male white leghorn chickens were killed by CO2 gas to determine the type, rate, and sequence of microscopic postmortem changes in the adrenal glands of dry and wet intact carcasses. They were held at 29 or 18 C with 50% relative humidity for different times postmortem. The sequence of microscopic postmortem changes was similar in all chickens except at 18 C, when karyorrhexis of cortical and medullary cells was observed. Cellular changes occurred earlier at 29 C than at 18 C and in dry chickens but not in chickens wet with detergent solution before storage, although slight quantitative and qualitative differences between wet and dry chickens were noted. Medullary cells underwent postmortem changes earlier than cortical cells. Nuclei of medullary cells decreased in size, with chromatin clumping leading to pyknosis, followed by cytoplasmic vacuolation, cellular shrinkage, and finally karyolysis and cell dissociation. Cortical cells had nuclear chromatin marginated, nuclei reduced in size initially, and some nuclear fading, followed by pyknosis and karyolysis. Karyorrhexis was not a prominent feature of cortical and medullary cells, although it occasionally occurred before pyknosis. Cytoplasm of cortical cells remained eosinophilic, granular, and vacuolated, but vacuoles became finer later. Pyknotic medullary cells with vacuolated cytoplasm were observed as early as 3 hr postmortem, regardless of the temperature. Diffuse pyknosis of medullary cells was noted at 18 hr in chickens held at 29 C and at 48 hr in chickens held at 18 C. Marked cortical pyknosis was noted only at 36 hr in wet chickens held at 29 C, when bacterial invasion started. Dry chickens held 36 hr at 29 C had diffuse cellular dissociation, karyolysis and cytoplasmic acidophilia, and marked bacterial invasion. Erythrocytes were pyknotic and had cytoplasmolysis. It was concluded that adrenal glands may still be useful for histopathological examination before 18 hr at 29 C and before 48 hr at 18 C.

Adrenal Cortex↗

Estimation of early postmortem intervals by a multiple regression analysis using rectal temperature and non-temperature based postmortem changes.

Five general methods based on rectal temperature and a multiple regression analysis using rectal temperature and non-temperature based postmortem changes were applied to 212 postmortem cases of within 24h postmortem (PM) intervals. Non-temperature based postmortem changes of rigidity, hypostasis and corneal turbidity were numerically categorized and used with rectal temperatures as four statistical variables in the multiple regression analysis. The correlation coefficient values between true and calculated postmortem intervals were 0.78-0.82 in the five general methods based on rectal temperature. The multiple regression analysis produced a multiple correlation coefficient value of 0.89 and according to the error ranges of the PM intervals, 72% of the cases were estimated within the error of +/-1.0 h and 92% within +/-5.0 h. Although assessments of non-temperature based PM changes are mostly subjective and have a wide variation, the present study demonstrated a usefulness of non-temperature based PM changes in the estimation of PM intervals.

Adolescent↗

Effects of ion channel blockers on rapid postmortem changes in extracellular dopamine and serotonin levels in the rat nucleus accumbens.

In the present study, we used in vivo brain microdialysis to examine the effects of ion channel blockers tetrodotoxin (TTX), EGTA-free Ca2+ and verapamil on rapid postmortem changes in extracellular levels of dopamine (DA), serotonin (5-HT) and their metabolites dihydroxyphenylacetic acid (DOPAC) and 5-hydroxyindoleacetic acid (5-HIAA) in the ACC of freely moving rats. Extracellular ACC DA levels decreased following the perfusion of the three ion channel blockers in freely moving rats, and then, at death by cervical dislocation, maximum respective 220-, 60- and 90-fold increases were observed in the extracellular output of DA in animals treated with EGTA, verapamil and TTX, respectively. Also, ACC 5-HT decreased following perfusion with the three blockers in the freely moving rats, and then maximum increases of 80-, 30- and 45-fold in the extracellular output of 5-HT were observed at death in animals treated with EGTA, verapamil and TTX, respectively, compared to the baseline. Cervical dislocation-induced rapid postmortem changes were inhibited markedly by perfusion with CSF containing the CA2+ entry blocker verapamil. These observations suggested that rapid postmortem changes in ACC DA and 5-HT release were associated with the action of calcium ion channels and/or voltage gated channels in the CNS.

Animals↗

Postmortem changes in catecholamines, indoleamines, and their metabolites in rat brain regions: prevention with 10-kW microwave irradiation.

Postmortem changes in catecholamines, indoleamines, and their metabolites in rat brain regions following decapitation were determined by LCEC. In the three regions studied neurotransmitter levels declined after decapitation, whereas the metabolite levels increased. Microwave irradiation at 10 kW rapidly inactivated brain enzymes and thus prevented the postmortem changes.

3,4-Dihydroxyphenylacetic Acid↗

A preliminary investigation into postmortem changes in skinfold impedance during the early postmortem period in rats.

A highly accurate and reproducible technique was used to measure the electrical impedance (1 kHz) of a lateral abdominal skinfold, in each of eight rat cadavers stored at 9.0 +/- 0.7 degrees C, during the early postmortem period. Impedance increased exponentially between 1 and 120 h post mortem. Whether or not similar changes occur during the human postmortem period, and their potential value as a means of objective estimation of postmortem interval (PMI), remains to be established.

Animals↗

Postmortem changes in tissue concentrations of triazolam and diazepam in rats.

The aim of this study was to investigate the postmortem changes of concentrations of triazolam and diazepam in the rat model and to confirm the factor causing the phenomenon. We administered triazolam or diazepam orally to rats and then sacrificed them 1 h after administration. Abdominal tissues including stomach content and small intestine, thigh muscle and heart blood were collected at 0, 12, 24 h after death, and postmortem changes of the two drug concentrations were compared. Drug concentrations in the samples were analyzed by a selected ion monitoring of gas chromatography/mass spectrometry. Gastrointestinal postmortem concentrations of triazolam and diazepam decreased. On the other hand, the drug concentrations in the liver and kidney increased markedly, and those in lung and heart blood increased slightly during postmortem periods by diffusion from the gastrointestinal tract. The patterns of both drug concentration changes were similar. However, the extent of the triazolam increase tended to be larger than that of diazepam. This difference may be accounted for by lower triazolam concentrations before death. The postmortem drug concentrations of thigh muscle did not change when administered with triazolam and diazepam. For both triazolam and diazepam, a significant correlation was observed in the drug concentration between the small intestine and the kidney at 24 h after death, indicating that major cause of the change in the drug concentration in the kidney was diffusion from the small intestine up to 24 h after death. The results in this study indicate that diazepam as well as triazolam diffuses from the gastrointestinal tract into the surrounding tissues after death and suggest that the diffusion is influenced by their pharmaceutical properties before death.

Animals↗

Sequential postmortem changes of glomeruli. Their detection by scanning electron microscopy.

Postmortem changes were studied by scanning electron microscopy (SEM) in renal tissue from five species of animals. Specimens were collected at intervals up to 24 hours after death. Six distinct morphological alterations were identified in the renal glomerulus, including capillary loop constriction, changes in microvillus morphologic features, podocyte surface blebs, swelling or fusion of pedicels, podocytes erosion, and retraction or loss of pedicels. Glomerular size remained nearly constant in all five species. The results of these studies demonstrate that pathologic evaluation by SEM of tissue specimens from the kidney is acceptable up to 60 minutes post mortem.

Animals↗