PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Postmortem Changes”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 451 records · Page 25Linked to original sources
PubMed2002

Preliminary study of the effect of acute antemortem haemorrhage on postmortem abdominal impedance in rats.

Studies over many years have revealed a consistent, inverse relationship between extracellular impedance of the rat abdomen and postmortem interval (PMI). Recent studies have shown that this relationship can be improved by correcting measured impedances to their theoretically predicted values at an arbitrarily chosen temperature of 40 degrees C, thus rendering them independent of the tissues' temperature at the time of impedance measurement. The present study, undertaken as a part of an ongoing effort to identify variables which might influence postmortem rate of change in abdominal impedance, was aimed at studying the possible effect of acute antemortem haemorrhage on abdominal impedance. Sudden loss of approximately 30% of the total blood volume, immediately prior to the death was without statistically significant effect on the pattern of postmortem change in abdominal impedance. Thus, in the control and experimental rats, respectively, impedance decreased progressively from 58.7 +/- 1.8 and 68.0 +/- 11.3 omega, 1 h postmortem, to 31.5 +/- 2.2 and 33.7 +/- 4.7 omega at a postmortem interval of 120 h (n = 6 in each group). In both groups, the relationship between impedance and postmortem interval was either linear or curvilinear. These findings are believed to mitigate in favour of continued effort to examine the potential usefulness of abdominal impedance, as an index of postmortem interval, under conditions encountered in routine forensic investigation.

Abdomen↗
PubMed2005

Postmortem stability of pituitary hormones in the human adenohypophysis.

The hypophysis is embedded in the fossa at the base of skull, having important functions in the hormonal system. The present study investigated its postmortem morphological changes and the stability of adenohypopyseal hormones. The pituitaries were collected at autopsy 6 h to 20 days postmortem and were studied by histology, immunohistochemistry and electron microscopy. To avoid the influence of prolonged brain hypoxia or swelling, subjects who survived not longer than 12 h were examined. Histological changes were seen in the nucleus 6 h after death, followed by cytoplasmic changes, and the cell shapes were hardly identifiable 7 days postmortem. Electron microscopy revealed evident ultra-structural changes 6 h postmortem, involving rough endoplasmic reticulum, Golgi complexes, mitochondria, nuclei and cell membranes. However, secretory granules remained well preserved 7 days postmortem. Immunostaining showed positivities for growth hormone, prolactin, adenocorticotropic hormone, luteinizing hormone and thyroid-stimulating hormone up to 15 days after death. These findings suggest the usefulness of immunohistochemical investigation of the adenohypophysis for estimating the time of death and endocrinologic evaluation in decomposed cadavers.

Adolescent↗
PubMed2003

Cannabis-sensitive dopaminergic markers in postmortem central nervous system: changes in schizophrenia.

BACKGROUND: This study investigated if changes in pre-synaptic markers on dopaminergic neurons (dopamine transporter [DAT], tyrosine hydroxylase [TH]) were present in the caudate from subjects with schizophrenia who had Delta(9)(-)tetrahydrocannabinol (THC) in their blood at autopsy. These changes were posited because animal studies show that treatment with THC decreases dopamine uptake and TH in the striatum. METHODS: Studies utilized caudate, obtained postmortem, from 14 schizophrenic and 14 control subjects. [(3)H]mazindol binding to caudate, measured using autoradiography, was taken as a measure of DAT; TH levels were estimated using an antihuman TH antibody and Western blotting. RESULTS: There was decreased [(3)H]mazindol binding to DAT in the caudate from the schizophrenic subjects with no detectable blood THC levels (THC(-)) compared with THC(-) control subjects (mean +/- SEM: 240 +/- 19 vs. 296 +/- 14 fmol/mg estimated tissue equivalents, p =.01). There were no significant differences between levels of DAT in the caudate from schizophrenic and control subjects that had THC in their blood. Tyrosine hydroxylase was not different in any diagnostic cohort. CONCLUSIONS: Our data suggests that DAT is decreased in the caudate from THC(-) subjects with schizophrenia, a change that may be reversed by ingesting THC from cannabis.

Adult↗
PubMedDate not supplied

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

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%.

Body Temperature↗
PubMed1984

Postmortem metabolism of short-finned squid muscle (Illex illecebrosus).

Postmortem biochemical changes were examined in the mantle muscle of the short-finned squid (Illex illecebrosus) in relation to the physical events associated with rigor. Unlike mammalian muscle, the major muscle phosphagen is arginine phosphate rather than creatine phosphate. Arginine phosphate levels did not change dramatically during the progress of rigor development. ATP depletion was found to be closely related to glycogen depletion as is often observed in mammalian muscle. The postmortem accumulation of octopine was related to the initial muscle glycogen content at death but a significant lag in its production was observed. The postmortem conversion of glucose to glucose-6-phosphate appeared to be the rate-limiting step in the overall conversion of glycogen to octopine. The intermediates found in the postmortem catabolism of squid muscle ATP were ADP, AMP, IMP Ino and Hx. Unlike most vertebrate fishes, AMP was found to accumulate in squid before conversion to IMP whereas accumulations of IMP and Ino were less than those normally found in vertebrate muscle.

Adenine Nucleotides↗
PubMed1981

Postmortem wound dehiscence: a medicolegal masquerade.

Postmortem artifactual changes associated with decomposition have been well reported throughout the forensic literature. The recognition and correct interpretation of these artifactual changes are of paramount importance in determining if injuries were sustained before or after death. Presented is a case of surgical wound dehiscence associated with bloating in the postmortem decomposition state. Previously undescribed in the current forensic science literature, this entity can present difficulties in interpretation. The artifact is described and the methods used in its identification are discussed.

Adult↗
PubMed2006

Changes in caspase activity during the postmortem conditioning period and its relationship to shear force in porcine longissimus muscle.

The objective of this study was to investigate the protease family caspases in skeletal muscle and their potential contribution to postmortem proteolysis and meat tenderization. Ten Large White gilts were slaughtered, and samples of LM were taken at 0, 2, 4, 8, 16, 32, and 192 h after slaughter and immediately snap frozen in liquid nitrogen. Samples were subsequently analyzed for caspase 3/7 and caspase 9 activity, protein levels of known caspase substrates, alpha II spectrin and poly (ADP-ribose) polymerase (PARP), as well as, at 192 h, shear force. Specific degradation products of alpha II spectrin and PARP, which are known indicators of caspase activity, and apoptosis were detected on immunoblots of muscle samples taken over the postmortem period. The relationships between the changes observed in caspase activities and protein levels of PARP and spectrin across the entire postmortem conditioning period were investigated (n = 70). Protein levels of alpha II spectrin cleavage products across the conditioning period were found to correlate positively to caspase 3/7 activity (r = 0.38, P = 0.003) and caspase 9 activity (r = 0.32, P = 0.012), indicating that caspase-mediated cleavage was occurring in situ. There was a negative relationship between shear force and the 0 to 32 h ratio of caspase 3/7 (r = -0.62, P = 0.053) and caspase 9 activities (r = -0.68, P = 0.044). In addition, there was also a negative relationship between shear force and the level of the caspase-generated alpha II spectrin 120 kDa degradation product (r = -0.75, P = 0.012). The findings of this study indicate that changes in caspase activity and caspase-mediated cleavage take place in muscle during the conditioning period, and this could be associated with the development of tender meat.

Animals↗
PubMedDate not supplied

Linear rate of change in the product of erythrocyte water content and potassium concentration during the 0-120-hour postmortem period in the rat.

An accurate and reproducible technique was employed for measurement of water content (RBCH2O) and potassium concentration (RBCK) in rat erythrocytes post mortem. Coefficients of variation for determination of RBCH2O and RBCK, as estimated from the results of duplicate analyses (n = 36), were 1.21% and 1.17%, respectively. Erythrocyte water content and RBCK were directly and linearly related (r = +0.93 (P less than 0.001], while the product of RBCH2O and RBCK varied linearly and inversely (r = -0.89 (P less than 0.001] with postmortem interval (PMI) over the 0-120-h postmortem period. In addition, the standard deviations of the data points for (RBCH2O X RBCK) remained relatively constant and independent of PMI. Attention is drawn to the possibility of determining time elapsed since death from (sequential) measurements of (RBCH2O X RBCK) in individual cadavers.

Animals↗
PubMed1999

Postmortem evaluation of morphologic changes in the infarcted myocardium that predict ventricular septal rupture in acute anteroseptal infarction.

Although thinning of the ventricular wall due to infarct expansion (septal aneurysm) may contribute to ventricular septal rupture (VSR), spatial factors predisposing to this mechanical complication have not been fully demonstrated. To identify the morphologic predictors of VSR, a retrospective postmortem study was performed on 17 hearts with acute anteroseptal myocardial infarction, comprising 7 with VSR and 10 without rupture. Infarct size and the extent of wall thinning were quantified. Wall thinning was defined as a decrease of less than 50% of thickness of the noninfarcted wall. The total infarct size did not differ among the groups. In the free wall (FW), the infarct was smaller in hearts with VSR than in those with a ruptured FW (p<0.05) or no rupture (p<0.01). The septal involvement was more extensive in patients with VSR than in those with FW rupture (p<0.05). Septal thinning was more extensive in hearts with VSR than in those with FW rupture (p<0.05) or non-rupture (p<0.05). A combination of a small infarct of the FW and a large septal infarct may contribute to the formation of septal aneurysm, which is believed to predispose to VSR. The presence of a small infarct of the anterior septum may be another setting for postinfarction septal rupture.

Aged↗
PubMed2006

Trends in postmortem aging in fish: understanding of proteolysis and disorganization of the myofibrillar structure.

Postmortem tenderization is caused by enzymatic degradation of key structural proteins in myofibrils as well as in extracellular matrix, and of proteins involved in intermyofibrillar linkages and linkages between myofibrils and the sarcolemma. The function of these proteins is to maintain the structural integrity of myofibrils. Current data indicate that calpains and cathepsins may be responsible for degradation of these proteins. Other phenomena occurring in cells postmortem (pH drop, sarcoplasmic Ca2+ increase, osmotic pressure rise, oxidative processes) may act in synergy with proteases. Our understanding of the underlying mechanisms of muscle degradation should be improved for an accurate evaluation of the postmortem muscle changes and consequently of the fish quality.

Animals↗
PubMed1994

Prerigor and postrigor changes in tenderness of ovine longissimus muscle.

A novel approach was used to measure the tenderness of prerigor ovine longissimus thoracis et lumborum by avoiding the confounding effects of heat-induced shortening resulting from cooking prerigor meat. The objective was to determine the tenderness of the muscle at the time of slaughter and to monitor changes in tenderness during rigor development and postmortem aging. Nine Romanov and 12 Finnsheep rams were slaughtered at 49.3 kg live weight. Samples of longissimus thoracis et lumborum were removed at 0, 3, 6, 9, 12, 24, 72, or 336 h after exsanguination. Five of the eight sample times were represented in each carcass and all carcasses were sampled at 0, 12, and 24 h. Prerigor muscle samples (0, 3, 6, 9, and 12 h) were clamped between two metal plates before excision to prevent shortening. The samples were frozen at -30 degrees C then stored at -5 degrees C for 10 d to allow glycolysis to proceed to completion, and thus ultimate pH and complete rigor mortis were attained. The longissimus thoracis et lumborum was then cut into chops and cooked and shear force was determined. Sarcomere length decreased through 24 h postmortem, then increased slightly through 336 h postmortem. Warner-Bratzler shear force values were 5.1 kg at 0 and 3 h, increased to 8.3 kg from 3 to 9 h, and then declined to 3.1 kg from 24 to 336 h postmortem. These data imply that longissimus thoracis et lumborum at slaughter is intermediate in tenderness, rigor shortening toughens the meat, and proteolysis tenderizes the meat, resulting in more tender meat after 14 d of aging than at slaughter.

Animals↗
PubMed1999

The extent of postmortem drug redistribution in a rat model.

The aim of this study was to investigate the postmortem redistribution of several drugs in a rat model and to examine if any of the pharmacological properties was related to the extent of this phenomenon. One of the following drugs: phenobarbital (phenobarbitone), acetaminophen (paracetamol), carbamazepine, codeine, verapamil, amphetamine, mianserin, trimeprazine (alimemazine) or chloroquine was administered together with nortriptyline orally to rats 90 min prior to sacrifice. Heart blood was sampled immediately before sacrifice and after 2 h postmortem, as it has previously been shown that this is sufficient time for postmortem concentration changes to occur in heart blood. Blood was also sampled from the clamped abdominal inferior vena cava (representing peripheral blood) and tissue samples were taken from lungs, myocardium, liver, kidney, thigh muscle, forebrain, and vitreous humor together with a specimen from the minced carcass. Drugs were analyzed by high performance liquid or gas chromatography. For phenobarbital, acetaminophen and carbamazepine the postmortem to antemortem blood drug concentration ratios were close to 1.0 and tissue concentrations were low. The postmortem to antemortem heart blood drug concentration ratio for chloroquine (6.9 +/- 1.5) was higher than for nortriptyline (3.5 +/- 0.3), and the remaining drugs (codeine, verapamil, amphetamine, mianserin, and trimeprazine) showed ratios of the same magnitude as nortriptyline. The postmortem to antemortem blood drug concentration ratios for both heart blood and blood from the vena cava and also the lung to antemortem blood drug concentration ratio were closely related to the apparent volume of distribution for the drugs studied (p < 0.001). Accordingly, an apparent volume of distribution of more than 3-4 L/kg is a good predictor that a drug is liable to undergo postmortem redistribution with significant increments in blood levels. The postmortem drug concentration in blood from vena cava was closely related to the antemortem blood level, confirming that among the postmortem samples, the peripheral blood sample was the most representative for the antemortem blood concentration.

Animals↗
PubMed1996

Postmortem distribution and redistribution of morphine in man.

This study evaluated both site dependent differences and time dependent changes in postmortem morphine concentrations in man. In 32 deaths involving morphine, left ventricular blood, femoral blood, and cisternal cerebrospinal fluid, were collected as soon after death as possible (T1), and collected again together with iliac blood at the time of autopsy (T2). Samples were analyzed for morphine by radioimmunoassay. No evidence was found for changes in morphine concentration with respect to time at either central or peripheral sites, or in the cerebrospinal fluid. Ventricular blood morphine concentrations were however consistently higher than those in the peripheral compartment, represented by either femoral or iliac blood. This was particularly true when the ventricular morphine concentration exceeded 0.300 mg/L. At peripheral sites, femoral and iliac blood morphine concentrations were well correlated with each other, making either an appropriate site for collection of peripheral blood for toxicological testing.

Adult↗
PubMed2006

[Relationship between the postmortem interval and nuclear DNA changes of heart muscular cells in mice].

OBJECTIVE: To study the changes of DNA degradation in cells of rats and its relationship with the postmortem interval. METHOD: 8 parameters of cell nuclear (including the tail length, the head radius, the percentage of head DNA, the percentage of tail DNA, the tail moment, the olive moment, the head area and the tail area) were chosen to study their changes in the procedure of DNA degradation in myocardium cells in 111 rats at different postmortem interval from 0 to 72 h by using single-cell gel electrophoresis (SCGE) technology and fluorescent microscope combined with auto-analysis-image system method. RESULTS: An evident comet tailing was observed in DNA of myocardium cells after electrophoresis, and their changes in all these 8 parameters of cell nuclear were greatly associated with the extension of postmortem interval, which indicate the degradation rate and degree of DNA in the nuclear has a close relationship with postmortem interval in the periods from 0 to 72 h in rats and significant difference were found with those groups (P < 0.001). CONCLUSION: The equations, which were concluded from our study, indicate the close relationship of degradation rate and degree of DNA in the nuclear with postmortem interval from 0 to 72 h, and provide an objective and exact new way to estimate the postmortem interval.

Animals↗
PubMed1997

Pulmonary and serum surfactant phospholipids and serum catecholamines in strangulation. An experimental study on rats.

Elevations of phospholipid and catecholamine concentrations in the blood are regarded as the vital reactions in asphyxial deaths, which leave few or no morphological signs in the body. These vital reactions were tested here, under strict experimental conditions, employing rapid asphyxia. Rats anaesthetized with barbiturate were strangled with a rope 2 mm thick tightened with a force of 29.4 N (3 kp). The main surfactant components, phosphatidyl choline and phosphatidyl ethanol amine, were measured in serum and lung samples, and catecholamines in the serum. The lungs were also investigated histologically. The serum phospholipid concentration in the strangulated rats was 1.36 +/- 0.32 g/l, versus 1.04 +/- 0.17 g/l in the controls (barbiturate intoxication), P < 0.001, but no change in their content was observed in the lungs (26.21 +/- 4.04 mg/g vs. 25.15 +/- 3.64 mg/g dry weight). Histologically, focal emphysema and tiny haemorrhages were seen in the lungs of both groups with similar frequency. Mean serum noradrenaline (NA) and adrenaline (A) concentrations were significantly higher in the strangulation group (NA = 5.4 +/- 2.6 ng/ml vs. 2.8 +/- 0.1 ng/ml, P < 0.001 and A = 6.0 +/- 3.4 ng/ml vs. 3.8 +/- 3.0 ng/ml, P < 0.05). The results support the notion that phospholipid and catecholamine concentrations are increased in the blood upon suffocation and could thus be taken as indicators of hypoxia. Further investigations into postmortem phospholipid change or stability are needed. There are reports that phospholipid concentration remain quite stable for two days post mortem, whereas catecholamine concentrations tend to rise quite soon after death.

Animals↗
PubMed2002

Circumstances and macropathologic findings in 1590 consecutive cases of bodies found in water.

The diagnosis of drowning relies primarily on critical examination of the subject's individual characteristics, circumstances, and postmortem macropathologic changes. In this retrospective study, based on 1590 consecutive cases of bodies found in water and undergoing autopsy at the Department of Forensic Medicine, University of Helsinki, from 1976 to 1998, the frequency of circumstantial data and macropathologic changes crucial for the diagnosis of drowning were determined. The fatal events were eyewitnessed in 403 cases (25.3%), and suicide notes were found in 83 cases (5.2%). External foam, frothy fluid in airways, and overlap of the anterior margins of lungs were found in 275 (17.3%), 739 (46.5%), and 669 (42.1%) of the cases, respectively, but no one of these changes, tested against dry-land controls, were specific for drowning. The association of external foam and overlap of the lung margins was exclusive of drowning but was observed in only 176 cases (11.1%). After cross-analysis, 964 (60.6%) of the cases had no circumstantial data or macromorphologic pathologic findings that allowed a definite diagnosis of drowning. The diagnostic problems in putative drowning cases, based on this study sample, have not been overrated. Studies to investigate and improve the reliability of complementary methods for the diagnosis of drowning are warranted.

Adolescent↗