[The specific features of corpse putrification under the influence of necrobiome enzymatic systems]

The objective of the present study was to characterize the specific features of corpse putrification under the influence of necrobiome enzymatic systems depending on the duration of the post-mortem period. We present the results of investigations into the enzymatic activity of the dominant species of microorganisms making up the post-mortem microbiome. The domestic pork carcasses weighing 50-70 kg were used as an experimental putrification model. The study revealed the characteristic features of protein decomposition under the influence of proteolytic enzymes of pseudomonads, bacilli, and clostridia, such as alteration in the amount of necrobionts producing proteases in the entire carcass and its fragments during biodegradation in the air over 30 and 136 days of the post-mortem period. A series of experiments designed to evaluate the effectiveness of protein hydrolysis by necrobionts have demonstrated the dependence of the rate of biodegradation on the environmental temperature, duration of the putrification pocess, and the species composition of the necrobiome.

A Comparison of Rapid Bovine Spongiform Encephalopathy Testing Methods on Autolyzed Bovine Brain Tissue

In 1999, the European Union (EU) approved 3 rapid methods for the testing of bovine brain samples for the presence of bovine spongiform encephalopathy (BSE). The evaluation that led to the approval did not include an analysis of autolyzed material. Member states of the EU have active surveillance programs for BSE, which target fallen stock as well as other categories of cattle. Autolysis is a common feature of fallen stock samples because there can be a considerable delay between death and collection of samples. Therefore, it is important to know whether these tests perform optimally on autolyzed samples. The Veterinary Laboratories Agency (VLA) selected 250 positive fallen stock samples. These had been detected during routine testing using the Prionics®-Check Western blot and confirmed as BSE cases by immunohistochemistry or electron microscopy. Samples were graded according to the degree of autolysis and then tested by the 3 methods: Prionics®-Check Western blot, Platelia test, and Enfer test. All 3 methods correctly classified the samples as positive BSE cases, therefore alleviating doubt about their ability to do so. Subsequent EU validation exercises, such as those conducted in 2002–2003, have included the testing of autolyzed material. It is important that all new methods be evaluated on autolyzed tissue before approval for official use.

[Dynamics of postmortem autolysis of cardiomyocytes]

Dynamics of postmortem autolysis of cardiocytes was evaluated using cells and tissues obtained from the patients who died from acute forms of ischemic heart disease, such as acute coronary insufficiency and acute myocardial infarction in the pre-necrotic phase. The studies were carried out at a temperature of 7, 20, and 37 degrees C. It was shown that autolysis of cardiac muscular fibers proceeds through three successive stages. A rise in temperature from 7 to 20 degrees C accelerated autolysis by one third while further elevation of the temperature up to 37 degrees C was associated with a 9-fold decrease in the duration of autolysis.

Paleohistopathology of bone: a new approach to the study of ancient diseases

Light microscopy, particularly the use of polarized light, has such a high value for the differential diagnosis of dry bones that it can no longer be neglected. Alterations caused intra vitam by disease or other living conditions can clearly be differentiated by this technique from changes due to postmortem reactions (e.g., pseudopathology). As a reliable diagnosis is the basis not only of the study of case reports but also of the etiology and epidemiology of diseases in ancient populations, paleopathologists would be well-advised to employ histological analysis for their research, to avoid false diagnoses. The necessary basis for such research is the knowledge of the general histology, histogenesis, and growth as well as pathophysiology of bone. Some new techniques which facilitate the practical use of microscopic analysis, such as the preparation of thin-ground sections from undecalcified bone samples and nonrehydrated mummified soft tissues, are described. Selected examples of mechanisms of pathological bone changes, particularly the determination of vestiges of diseases in macerated bones by microscopy, are presented. Emphasis is placed on the differential diagnoses of proliferative reactions (e.g., periosteal processes of long bones and the skull). In this context, the importance of meningeal reactions on the endocranial lamina of the skull for morbidity and mortality in ancient populations is demonstrated. Furthermore, porotic hyperostosis of the skull vault and the orbital roof, i.e., the cribra cranii externa and cribra orbitalia, is discussed. Selected examples of the etiology and epidemiology of ancient diseases are presented (e.g., anemia, scurvy, rickets, and meningeal diseases), and ideas on living conditions and their implications for the origin and the spread of disease are given to establish a better understanding of deficiency and infectious diseases in the past.

Hypoxic changes in Purkinje cells of the human cerebellum

The significance of both Purkinje cell numbers and various neuronal changes for the diagnosis and timing of hypoxic-induced brain lesions was investigated in tissue samples from the cerebellar cortex of 52 individuals with a history of acute or prolonged cerebral hypoxia/ischemia before death. Furthermore, the area of the Purkinje cell somata (PC size) was measured using an automatic image processing and analysis system (LEICA QWin). Significantly reduced numbers of Purkinje cells (<6 cells/unit length of 1 mm) and a decreased portion (<50%) of intact Purkinje cells could be detected in individuals with a period of resuscitation of at least 2 h after acute circulatory arrest. Average cell numbers of less than 4 cells/unit were found in individuals who suffered from diffuse brain swelling and were ventilated for at least 3 days, as well as in individuals who died of brain death. Moreover, the Purkinje cells in these cases exhibited shrunken somata compared to the controls. Specimens that were stored at room temperature up to 30 h after removal at autopsy showed no significant autolytic changes of the Purkinje cells. After 46 h, however, reduced Purkinje cell numbers and shrunken cell bodies were found.

Diagnosis of Alzheimer's disease in an exhumed decomposed brain after twenty months of burial in a deep grave

After 20 months of interment in a deep grave, the decomposed body of the 81-year old testator of a will was exhumed to sustain the burden of proof that he lacked testamentary capacity when the will was rewritten two days prior to his death. The brain was mushy and pulverized with complete disappearance of the brainstem, cerebellum and subcortical ganglia. Small foci of relatively intact dorsal frontal neocortex were identified. Sections from these foci were stained with hematoxylin and eosin, bielchowsky silver stain and immunostains for beta amyloid peptide (betaA4), tau and alpha-synuclein. Despite severe autolysis and decomposition, the bielchowsky stain and the betaA4 immunostains showed preserved frequent neuritic amyloid plaques with very few residual neurofibrillary tangles. Cerebral Amyloid Angiopathy was present. At the present time this case represents the first documented and reported case of direct tissue diagnosis of Alzheimer's Disease pathology in a decomposed brain following long term burial in a deep grave.

Analysis of rugae in burn victims and cadavers to simulate rugae identification in cases of incineration and decomposition

The most challenging situations in Forensic Odonto-Stomatology are mass disasters, where the forensic dentist is usually confronted with charred human remains or heavily decomposed or fragmented bodies. This article determines the extent of preservation of palatal rugae for use as an alternative identification tool in such situations, using a study group comprising burn victims and cadavers simulating forensic cases of incineration and decomposition. The thermal effects and the decomposition changes on the palatal rugae of burn victims with panfacial third degree burns and human cadavers in storage were respectively assessed and graded on a new scale. Ninety three percent of burn victims and 77% of human cadavers had Grade 0 changes (normal). When changes were noted, they were less pronounced than the generalized body involvement of burns in burn victims and the generalized body decomposition of human cadavers.

Preanalytic aspects in postmortem toxicology

The preanalytic phase has been recognized to have a substantial role for the quality and reliability of analytical results, which very much depend on the type and quality of specimens provided. There are several unique challenges to select and collect specimens for postmortem toxicology investigation. Postmortem specimens may be numerous, and sample quality may be quite variable. An overview is given on specimens routinely collected as well as on alternative specimens that may provide additional information on the route of administration, a long term or a recent use/exposure to a drug or poison. Autolytic and putrefactive changes limit the selection and utility of specimens. Some data from case reports as well as experimental investigations on drug degradation and/or formation during putrefaction are discussed. Diffusion processes as well as postmortem degradation or formation may influence ethanol concentration in autopsy specimens. Formalin fixation of specimens or embalmment of the corpse may cause considerable changes of initial drug levels. These changes are due to alterations of the biological matrix as well as to dilution of a sample, release or degradation of the drug or poison. Most important seems a conversion of desmethyl metabolites to the parent drug. Some general requirements for postmortem sampling are given based on references about specimen collection issues, for a harmonized protocol for sampling in suspected poisonings or drug-related deaths does not exist. The advantages and disadvantages of specimen preservation are shortly discussed. Storage stability is another important issue to be considered. Instability can either derive from physical, chemical or metabolic processes. The knowledge on degradation mechanisms may enable the forensic toxicologist to target the right substance, which may be a major break down product in the investigation of highly labile compounds. Although it is impossible to eliminate all interfering factors or influences occurring during the preanalytic phase, their consideration should facilitate the assessment of sample quality and the analytical result obtained from that sample.

Ultrastructural changes during in situ early postmortem autolysis in kidney, pancreas, liver, heart and skeletal muscle of rats

Many morphological studies of the postmortem interval were carried out under conditions in which the tissue was incubated in vitro after extirpation. However, the extirpation affects cell viability. We examined the ultrastructural changes in the kidney, pancreas, liver, heart and skeletal muscle of male Wistar rats occurring postmortem in situ. In each organ, cell edema (cell swelling), appearance of amorphous dense deposits in the mitochondria, loss of glycogen granules, dilation of the endoplasmic reticulum, clumping and margination of nuclear chromatin, and/or condensation of nuclear chromatin were observed, but the duration of the period of ultrastructural change was organ specific. Most of the ultrastructural changes occurred earlier in kidney. In hepatocytes, the morphological degeneration occurred later than in the renal tubule epithelium and earlier than that in the myocardium. Of the five organs we examined, skeletal muscle showed the greatest delay in postmortem change. In the distal tubule epithelium and pancreatic acinar cells, two forms of nuclear change were seen: one resembled necrotic change and the other resembled apoptotic change. The effect of lysosomes and hydrolytic enzymes was not as great as previous findings.

A simple method for the prevention of endometrial autolysis in hysterectomy specimens

AIMS

Uteri are among the most common surgical pathology specimens. Assessment of the endometrium is often difficult because of pronounced tissue autolysis. This study describes a simple method to prevent endometrial autolysis and aid in interpretation of the endometrium.

METHODS

Sixty uteri were injected with formalin using a needle and syringe directed alongside a probe, which was inserted through the external cervical os into the endometrial cavity. Injection was performed on the same day as removal of the uterus. As controls, 60 uteri that were not injected with formalin were examined. The degree of endometrial autolysis was assessed on a four point scale (0-3), with a score of 0 representing no or minimal autolysis and a score of 3 representing extensive autolysis, such that histological interpretation of the endometrium was impossible.

RESULTS

In the injected group, the number of cases with scores of 0, 1, 2, and 3 was 42, 13, four, and one, respectively. The corresponding values for the control group were 17, 23, eight, and 12, respectively. This was highly significant (p < 0.001)

CONCLUSIONS

There was significantly less endometrial autolysis in uteri injected with formalin. The use of this simple procedure should be encouraged in hysterectomy specimens.

[A hopeless case?]

In a hollow covered with earth, a herb gatherer discovered a severely decomposed corpse mutilated by scavenging animals. Only small areas of the skin had remained intact. A conspicuous tattoo could still be distinguished on the left upper arm. Despite concrete evidence of violence (fracture in the occipital bone, subdural hemorrhage with a volume of 20 ml), the exact cause of death could no longer be established. Police enquiries identified a person in whom such a conspicuous tattoo had been photographed in an earlier criminal case. Eventually, the deceased person could be identified by DNA analysis of a stored blood alcohol specimen. Considered together, the autopsy findings and the results of the investigation of traces of blood on the putative tool used in the crime indicated that the man had been struck dead and the body had afterwards been buried in the wood. Although the prospects of success had been initially slight, it was not only possible to identify the victim, but also to reconstruct the crime.

[Ultrastructure changes of liver autolysis]

Ultra-structure changes of autolysis of hepatocyte were studied using transmission electron microscope(TEM). It was found that autolysis started 0.5 hour after death, with the heterochromatin of nuclei shrinking abnormally and smooth endoplasmic reticulum expanding. The changes developed to distinction after 1 h, and progressed continuously after 2 h, 3 h, 4 h and 5 h. It was found that (1) the mitochondria were swelling, its matrix density decreasing and flocculent dense bodies (FDB) emerging; (2) the rough endoplasmic reticulum and perinuclear cistern were expanding. It was suggested that ultra-structure changes of the autolysis be correlated to the postmortem time.

Catenin dislocation in oral pemphigus vulgaris

Cell-to-cell adhesion is mediated by cadherins (integral membrane proteins), which form a complex with catenins (cytoplasmatic proteins). While E-cadherin expression has been extensively studied in many human skin diseases, less is known about the expression levels of catenins in oral blistering diseases. The purpose of this study was to evaluate the role of these proteins in the pathogenesis of acantholysis in oral pemphigus vulgaris. We evaluated by immunohistochemistry beta- and gamma-catenin expression in 7 cases of oral pemphigus vulgaris (PV) at various stages of the disease and, as controls, in 18 healthy patients. Healthy cases showed, as reported in the literature, a strong reactivity with both beta- and gamma-catenins, with the intensity of staining progressively decreasing from the spinous to the keratinised layers of epithelium, which had a prevalent cellular membrane expression. In PV patients, we detected a loss of membrane expression of these molecules with a progressive displacement of the signal toward the cytosol and, for gamma-catenin, nuclear dislocation, particularly in areas with intense acantholysis.

Demonstration of myocardial necrosis in the presence of advanced putrefaction

Samples of heart tissue were investigated in two series for the detectability of myocardial necrosis after artificial and natural putrefaction, respectively. In the first series heart tissue with and without infarction was artificially subjected to humid and dry autolysis and putrefaction. In the second investigation heart tissue was obtained from exhumed bodies after periods of burial ranging between 10 and 929 days. Besides histology a variety of immunohistochemical markers were applied and C5b-9 gave positive results even after long periods of artificial and natural putrefaction. From the methods tested, this was by far the most sensitive method with a high robustness against putrefaction. NP57, which indicates neutrophilic leucocytes could be demonstrated considerably longer after humid putrefaction than after dry putrefaction. The time limits of detection were considerably longer than for H&E. These two methods are the methods of choice for the detection of myocardial infarction and leucocyte infiltration in advanced stages of putrefaction.

Neuronal nuclear DNA fragmentation in the aged canine brain: apoptosis or nuclear DNA fragility?

Neuronal DNA fragmentation, as revealed with the method of in situ end-labeling of nuclear DNA fragmentation (TUNEL), has been reported in both the canine and human brains in normal ageing, and in some human age-related neurodegenerative diseases. These results have suggested that apoptosis plays an important role in age-related neuronal loss. It is not clear, however, whether the TUNEL method is highly specific for apoptosis, as DNA fragmentation also occurs in the late stages o necrosis. In this study we have examined 27 dogs aged from 8 to 18 years, to investigate the occurrence of nuclear DNA fragmentation. An autolysis index based on current histological criteria was assigned to each animal to evaluate the effects of autolysis on nuclear DNA integrity. Our results have shown that neuronal nuclear DNA fragmentation is frequent in aged dogs, although it is not accompanied by apoptotic morphology. Yet, a positive relation between TUNEL labelling and the degree of tissue autolysis was observed. In contrast, no TUNEL labelling was detected in young control dogs despite autolysis indices being similar to those in aged dogs. Taken together, these results suggest that neuronal nuclear DNA fragmentation is an age-related phenomenon, not due to apoptosis, whenever other factors render neuronal DNA more susceptible to autolytic fragmentation. We confirm the effect of autolysis in a subpopulation of neurons in the aged canine brain, inducing nuclear DNA fragmentation.

Evaluation of cardiac troponin I immunoreaction in autopsy hearts: a possible marker of early myocardial infarction

Postmortem diagnosis of early myocardial infarctions is an ever recurrent problem in pathology. In the present study we determined the troponin I expression in 46 autopsy hearts using an immunohistochemical technique. Troponin I has, as a specific cardiac muscle protein, become a widespread used marker in testing patients with acute chest pain. The hearts were divided into three groups based on the macroscopical findings: definite signs of infarction, possible signs of infarction and no signs of infarction. All 14 cases of definite myocardial infarction showed a well-defined area with loss of troponin I. Twenty-three of 24 cases of possible myocardial infarction also showed a well-defined area with loss of troponin I. None of the eight non-cardiac death controls showed loss of troponin I expression. The results suggest troponin I expression as a sensitive test in diagnosis of early myocardial infarction.

Densitometric and chromatin texture parameters of hepatocyte nuclei during controlled autolysis

OBJECTIVE

To determine the extent of the effect of autolytic changes in hepatocyte nuclei on the results of measurements of integrated optical density (IOD) of nuclei stained by the Feulgen method and its possible relationship with changes in chromatin texture.

STUDY DESIGN

Cytologic smears obtained from five pig livers by means of fine needle biopsy were fixed in 10% formalin at six time points after slaughtering (0-18 hours) and stained per Feulgen. In the hepatocyte nuclei IOD measurements were performed and supplemented with quantitative texture analysis. Texture analysis was carried out with our own algorithm, based on the movement of global gravity centers of heterochromatin granules during two-level, iteratively changed, grey thresholding.

RESULTS

The variability coefficients of IOD of diploid hepatocytes during autolysis increased from 0.061 (0 hours) to 0.363 (18 hours), and the ploidy histograms became aneuploid. The texture of chromatin became more homogeneous, but other features of the texture did not indicate a significant correlation with the duration of autolysis.

CONCLUSION

Autolysis is an important factor, which may influence the accuracy of DNA content and shape of ploidy diagrams. Changes in the morphologic pattern of heterochromatin may play a role in this, but the study was not conclusive because only one of six texture parameters (number of granules) changed parallel to mean IOD and autolysis time.

Postmortem delay and temperature conditions affect the in situ end-labeling (ISEL) assay in brain tissue of mice

Apoptotic cell changes occurring under certain developmental, physiological, and pathological conditions have been of increasing interest during recent years. Due to occasional difficulties in detecting apoptosis in routinely stained sections, various methods have been developed to facilitate tissue examination. Fragmentation of DNA during the process of apoptosis is a prerequisite for detection in the in situ end-labeling (ISEL) procedure. It is yet unclear whether other mechanisms of cell change that induce DNA fragmentation such as necrosis and postmortem autolysis also show positive staining with the ISEL technique. To investigate whether the ISEL assay visualizes autolytic DNA changes along with apoptotic DNA fragmentation, we tested the technique on brain tissue of mice after different time intervals (0, 6, 12, 24, 48, 72 h) of postmortem delay (PMD) and at 2 different temperatures of postmortem storage (4 degrees C and room temperature (RT)). Our semiquantitative results show that up to 24 h of PMD no prominent difference in labeling is observable at both temperatures. After 48 and 72 h of PMD at RT clusters of labeled cells begin to appear. Clusters of stained cells should therefore not be considered as apoptosis when using the ISEL assay.

Morphology of sweat glands in determining time of death

This study demonstrates post-mortem autolytic alterations in the skin at cellular and subcellular levels and identifies parameters which may assist in determining the time of death in the first few hours post-mortem. Serial skin samples from the ventral surface of the arm were taken at intervals of 3, 6, 9 and 12 h after death in 29 subjects of various ages, with no signs of skin disease; causes of death were various. Three types of tests were performed: cytochemical (hematoxylin-eosin and alcian-PAS), immunohistochemical (S-100, CEA, Cytokeratin, ASM) and ultrastructural (electron microscopy). Electron microscopy proved useful for identifying transformations which were found to be specific for each chronological step considered: reduction of intracellular glycogen in clear cells and reduction of secretory granules in dark cells are typical signs of the first stage (3 h) after death; mitochondrial dilatation and rarefaction of cristae in clear and dark cells are typical of the second stage (6 h); rarefaction of microvilli in dark and clear cells is a sign of the last stage (12 h). Cytochemistry and immunohistochemistry supply useful information--not for all the chronological stage considered here, but for individual phases (3 h for hematoxylin-eosin and 6 h for alcian-PAS). However, it is particularly important to use the results from all such techniques simultaneously, so that the question of the exact time of death within the first 12 h post-mortem may be more accurately answered.

Ischemic changes in fetal myocardium. An autopsy series

It has been assumed that fetal myocardial necrosis is an uncommon event that occurs only under unusual circumstances. We studied random heart sections on 76 fetal and perinatal autopsies from a 4-year period to determine the types and frequency of histologic abnormalities that occur in fetal myocardium. Vacuolar degeneration was extremely common (43% of stillbirths, 84% of live births) but a nonspecific finding. Ischemic changes, which are typically associated with coagulation necrosis, myofiber waviness, or contraction band necrosis, were seen in 21% of stillbirths and 32% of live births. In the majority of cases with histologic evidence of ischemic change, a combination of either contraction band necrosis, coagulation necrosis, and/or myofiber waviness was identified. Only rarely was any one of the abnormalities seen as an isolated feature. In only two autopsies were the ischemic changes identified in the initial autopsy report. We conclude that the histologic changes associated with ischemia that may represent myocardial necrosis are not uncommon and are frequently overlooked at autopsy.

Biochemical, morphological and cytochemical studies of enhanced autolysis of Saccharomyces cerevisiae. 2. Morphological and cytochemical studies

Morphological and cytochemical observation of Saccharomyces cerevisiae undergoing of induced autolysis were done in response to various chemical inducers of autolysis (NaCl, ethanol, fresh autolyzate). Changes in the inner structure of yeast cells were monitored by transmission electron microscopy and the surface of the cell wall was observed by scanning electron microscopy during autolysis. Cytochemical characterization of autolyzed cells was performed using four synthetic substrates for determination of proteinase activities but only carboxypeptidase Y could be detected in the vacuolar membranes. The morphological studies supported the data obtained from biochemical studies and confirmed that optimized conditions of autolysis have a significant effect on the structural changes of autolyzed yeast.

[The ultrastructure of the pancreatic endocrinocytes of human fetuses in postmortem autolysis]

The method of electron microscopy was used to study the morpho-functional state of pancreatic islands of human fetuses at different terms (10-54 h) after clinical death. Within the periods of time in question the island secretory cells preserve the structure characteristic of each type (B, A, D). The development of symptoms of postmortem autolysis of the pancreatic island is not a chaotic fleeting physico-chemical reaction and is characterized by a definite sequence of cytological changes of endocrinocytes. A conclusion is made that cadaveric material of the pancreas is good for preparing the pancreatic island culture for using it in the following tissue substituting therapy of patients with diabetes mellitus.

Experimental corneal cryopreservation: impact of postmortem time on corneal endothelial cell survival

Clinical and experimental studies with rabbit and human corneas have shown the correlation between short postmortem times and successful corneal cryopreservation. In this experimental study we investigated this phenomenon considering the latent freeze-thaw-induced cell damage. Enucleated eye-balls of freshly slaughtered pigs were stored in moist chambers at 4 degrees C for 2, 4, 8, 16, 32, and 72 h before cryopreservation. After thawing, the corneas were organ-cultured for 1 day. After staining with trypan blue and alizarin red S the tissue was evaluated morphometrically, calculating the amount of necrotic areas on the central corneal surface and the endothelial cell density. Corneas stored up to 32 h before cryopreservation showed no difference regarding the amount of necrosis and endothelial cell density compared to freshly cryopreserved tissue. Corneas stored 72 h before cryopreservation revealed no endothelial cell survival. We conclude that a post-mortem time of up to 32 h before corneal cryopreservation has no influence on endothelial cell survival.

Differentiation of lesions caused by mycotoxin T-2 from autolytic morphologic change in CD-1 mice

Experiments with topically applied T-2 trichothecene mycotoxin were undertaken to determine whether lesions caused by this toxin could be differentiated from autolysis. Two pathologists, who had previously seen lesions caused by T-2 toxin, graded lesions without knowledge of treatment group and stated whether the animal had received the toxin or not. Both pathologists differentiated T-2 toxin-treated mice up to 6 h post-mortem. Failure to distinguish between treated and control mice resulted in false-negative diagnoses only. It was concluded that the diagnosis of trichothecene mycotoxicosis would probably be missed more than 6 h post-mortem.

Intravascular "mulberry-like" bodies: morphological, immunohistochemical, and ultrastructural observations of an incidental finding caused by autolysis?

Intravascular "mulberry-like" bodies in a stillborn female infant with moderate maceration are reported. The histogenesis of these structures is discussed based on light-microscopic, immunohistochemical and ultrastructural findings. No demonstrable causal relation between the intravascular lesions and fetal death was found, the cause of death being attributed to intrauterine asphyxia. It is concluded, that intravascular "mulberry-bodies" most likely represent artifacts due to red blood cell autolysis.

Myofibrillar degeneration and necrosis of the visceral smooth musculature: an ischemic visceral myopathy

Pathologic studies of the visceral smooth musculature in humans are scant despite the relatively frequent occurrence of alterations in these muscles in autopsy material. We investigated the different types of lesions of this musculature observed in various conditions associated with ischemia--acute tubular necrosis, congenital heart disease (low output syndrome due to open heart surgery), and necrotizing enterocolitis in premature babies. Control cases included normal rat tissue undergoing autolysis and rigor mortis and bowel resected from patients with ulcerative colitis and Hirschsprung's disease. Four histologically distinct lesions were present on hematoxylin--eosin staining in the ischemic group: contraction bands, wavy fibers, thick waves, and coagulation necrosis. These lesions were absent in the control groups. We conclude that myofibrillar degeneration and necrosis of the visceral musculature are common in disorders associated with visceral ischemia. These changes are not artifacts produced by autolysis, rigor mortis, or technical handling, nor are they induced by nonischemic inflammatory conditions. Catecholamines may play a role in their genesis.

Rapid postmortem gut autolysis in infant rats: a potential problem for investigators

Experiments were designed to determine the rate and nature of postmortem autolysis in the gut of neonatal rats, as necessary baseline information for developing a model of human neonatal necrotizing enterocolitis. We studied 60 animals, including 33 Wistar rats, 18 Sprague-Dawley rats and nine CD-1 mice. The variables examined included age of the animals (2 or 14 days) and length of delay and holding temperature (20 degrees C or 37 degrees C) after sacrifice. At necropsy, bowel was rapidly removed and fixed for histopathological examination. In all instances, bowel removed immediately after sacrifice was normal whereas after delays as short as 30 minutes it was abnormal (P less than 0.001), becoming markedly so after 60 minutes. The prominent features were detachment and lysis of mucosal epithelial cells. The rate of autolysis was not altered in 14 day old animals or in carcasses held at 20 degrees C or 37 degrees C. Investigators of bowel injury syndromes in young rats should be aware that histopathological studies will be valid only if specimens held at room temperature are fixed within 15 minutes of death.

Persistence of mitochondrial competence during myocardial autolysis

The rate of irreversible loss of mitochondrial phosphorylating respiratory function with NAD-linked substrates during zero flow myocardial autolysis at 37 degrees C was gradual and relatively linear with time, progressing at about 1% of the control activity per minute. State 3 respiratory rates and initial rates of inner membrane potential development dropped off in close parallel with one another as well as with NADH-coenzyme Q (CoQ) reductase activity, suggesting that oxygen uptake as well as membrane potential development were rate limited by the increasing impairment of electron flow through complex I. Although the initial rate of membrane potential development dropped off gradually, the time course for the loss of the ability to ultimately develop and hold a full potential was slower still, there being only a moderate impairment of this ability at 80 min of autolysis. This sustained ability to develop and hold a membrane potential after more than 1 h of autolysis suggested that inner membrane leakiness contributed little or not at all to the functional impairment observed. The irreversible loss of mitochondrial inner membrane competence emerged in these studies as a relatively late development in the sequence of cellular alterations which characterize the myocardial ischemic process.

Autolytic changes of human white matter: an electron microscopic and electrophoretic study

The effect of autolysis on the electrophoretic pattern of the 3H-labeled membrane glycoproteins derived from human brain white matter (WM) was investigated and correlated with electron microscopic findings. Samples were taken from the WM of outer zones of routine surgical specimens sent for pathologist's examination. The WM samples were incubated at +4 and +25 degrees C for 6 and 24 hr and analyzed by electron microscopy and by galactose oxidase labeling with subsequent SDS-polyacrylamide gradient gel electrophoresis. The effect of freezing and thawing was also studied. In electron microscopic examination myelin was found to have degenerated after an incubation of 24 hr at +4 and +25 degrees C, and it was severely disrupted after 24 hr at +25 degrees C, when a periaxonal network-like change was observed. The major labeled membrane glycoprotein band with an estimated molecular weight (MW) of 138,000 was stable during the first 24 hr of incubations at both +4 and +25 degrees C. No marked changes were noticed in the electrophoretic pattern of all of the WM membrane proteins labeled by [3H]acetic anhydride technique. In frozen and thawed specimens there was an increase in the intensity of the band with a MW of 86,500 and a new band appeared at the MW region of 25,000. The present results suggest that despite the apparent stability of the major glycoprotein band during the first 24 hr of autolysis, there are ultrastructural abnormalities in the myelin sheath, which should be taken into consideration during interpretation of changes in pathologic conditions.

Effect of synthetic metalloprotease inhibitors on cartilage autolysis in vitro

The role of chondrocyte metalloprotease (CMP) in mediating cartilage autolysis was studied. Proteoglycan (PG) release and synthesis by rabbit articular cartilage explants were measured. After a 1-day preculture in control medium, 3.3 X 10(-6) M retinoic acid (RET) treatment for 1 day stimulated PG release several fold. RET also caused a large decrease in PG synthesis that returned to the control level after a 3-day recovery period. The effect on PG synthesis was observed at serum levels of 5 and 0.05%. The effect of RET on PG release required protein synthesis, inasmuch as it was lost in cultures maintained in media without amino acids or in a low volume of media. Interleukin-1 (IL-1) and lipopolysaccharide (LPS) treatment for 2 days also stimulated PG release. More PG was released after RET than after IL-1 or LPS, and only RET produced an effect that was evident by day 1. The amount of CMP that produced the same size effect on PG release as these stimulators was below the detection level of PG protease assays. Three potent CMP inhibitors reduced RET-, IL-1- and LPS-stimulated PG release to control levels. These inhibitors did not block another action of RET on chondrocytes, namely the inhibition of PG synthesis by RET immediately after treatment. The inhibitors did not act by reducing cell viability, because recovery of the rate of PG synthesis 3 days post-treatment occurred in inhibitor-treated cultures. These studies suggest that CMP is involved in cartilage autolysis that is stimulated by RET and IL-1.

Spinocerebellar degeneration with prominent involvement of the motor neuron system: autopsy report of a sporadic case

A sporadic case of spinocerebellar degeneration with prominent involvement of the motor neuron system is reported. A Japanese male without contributing family history, developed cerebellar ataxia at the age of 52, followed by generalized amyotrophy and ophthalmoplegia, and died aged 58. The clinical findings were pathologically verified as degeneration of the spino-ponto-cerebellar system and the motor neuron system, the latter almost identical to those of amyotrophic lateral sclerosis. Additional subclinical changes were found in the dentate nucleus and substantia nigra. Brain-stem nuclei subserving eye movements were well preserved, suggesting a supranuclear basis for the ophthalmoplegia. This unusual combination of system degenerations has on rare occasions been reported in the heredofamilial cerebellar disorders. As a sporadic case, however, this may be the first autopsy case of spinocerebellar degeneration with severe concurrent involvement of the motor neuron system.

Autolysis of the granular layer of the cerebellar cortex in brain death

In a study of duration of brain death, granular layer autolysis (GLA) of the cerebellar cortex was analyzed in 45 patients who died of acute cerebrovascular diseases (CVDs). Twelve patients who died of causes other than intracranial disease served as controls. Tonsillar herniation occurred in all who died of acute CVDs. More advanced GLA was seen in the central folia adjacent to the central white medullary body of the cerebellum as compared with the peripheral folia. Widespread GLA involving the most of the peripheral folia was found solely in patients in whom brain death had been present over 18 h. Of the 12 control patients, 4 showed GLA only in the central folia. Although GLA of the central folia might develop during immersion fixation of the brain, the alteration of the peripheral folia is assumed to develop in the period of brain death. Widespread GLA extending to the peripheral folia could be a pathological finding characteristic of brain death, where intracranial blood flow could be absent or significantly reduced. Brain death for little less than 1 day would be necessary for GLA to develop.

A scanning electron microscopy study of post mortem autolytic changes in the human and rat cochleas

The use of SEM as an adjunct to TEM and electrophysiological examination of the cochlea is now well established. It has provided a relatively simple method of assessing the effect of noise, ototoxic drugs, electrical stimulation, etc. on the surface features of the organ of corti. A controlled experiment was undertaken to document the surface autolytic changes in rat cochleas by fixation at intervals up to eight hours post mortem. These were compared with human material fixed between 40 minutes and eight hours post mortem. The results complement previous light and transmission electron microscopy studies, gives insight into the optimal and acceptable fixation times for the two species and act as a guide for the interpretation of human material.

[Detection of diphenhydramine in autolytic brain tissue in poison-induced brain death syndrome]

A case of accidental monointoxication caused by diphenhydramine is reported. Having taken 12 dragées of Neo-Emedyl (50 mg diphenhydramine), an 18-month-old girl showed the following symptoms: generalized erythema, dyspnoea, vomiting, hyperpyrexia, tremor, convulsions, coma, respiratory arrest and absence of reflexes. Computed tomography (CT) suggested a massive cerebral oedema. Her electroencephalogram was abnormally diffused at first; later on, it flattened significantly and became isoelectric between the 14th day and the final stoppage of circulation (after 5 weeks). Autopsy revealed total necrosis of the brain, with the venous cerebral blood vessels being thrombosed (the morphological basis for dissociated cerebral death). In autolysed brain tissue, diphenhydramine was detected at a concentration of 30 ng/g by GC/MS (gas chromatography, mass spectrometry); the concentration of the substance was less than 10 ng/g in the liver. The relatively high concentration in the brain was due to the previous blocking of the circulation. Cerebral death syndrome caused by intoxication offers the chance of detecting measurable amounts of the unchanged drug in autolysed brain tissue.

Renal tubular epithelia ultrastructure in autolysis

Post-mortem changes in the proximal and distal tubules of rat kidneys left in situ have been studied at the light microscope and ultrastructural levels. The distal tubular nuclei showed distinct changes which were completely different from the usual nuclear appearances after death and resemble the changes seen in apoptosis. These observations suggest that the unusual changes in the autolytic distal tubular nuclei may be due to the activation of endogenous endonucleases.

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.

Comparative biochemistry and fine structure of atrial and ventricular myocardium during autolysis in vitro

In a previous study we found that the development of fine structural alteration in atrial myocardium made ischaemic in vivo was slower than has been observed for ventricular myocardium. To explore possible reasons for this, parallel samples of atrial (A) and ventricular (V) myocardium undergoing autolysis (ischaemic necrosis) in vitro at 37 degrees C were studied for up to 2 hours. At 15-minute intervals tissue was snap-frozen for measurement of pH, lactate, and adenine metabolites by HPLC. In half the experiments comparable specimens were taken for electron microscopic examination as well. Fine structural alteration developed less uniformly and more slowly in A than in V. The most striking metabolic differences between A and V were: A had a consistently higher tissue pH and lower lactate level The sum of the adenine + hypoxanthine metabolites was essentially constant but significantly different for each (A = 5.04 +/- 0.12 (s.e.m.), V = 7.71 +/- 0.15 (s.e.m.) mumol/g wet tissue weight) Initial ATP levels were lower (40% less) in A The maximum accumulation of AMP was higher in A, despite its smaller pool of adenine metabolites Both adenosine and inosine showed slower rates of change in A. These results suggest that during early, severe ischaemic injury A and V show differing activities of 5'-nucleotidase.

Respirator retina

Retinas from 14 comatose patients, who had been sustained with a respirator for one or more days before death, had selective characteristic alterations (ie, autophagy, cell swelling, and coagulation necrosis) of inner nuclear layer in a patchy pattern in posterior fundus. Bipolar cells were most often affected, but amacrine and horizontal cells also were substantially damaged. Cells of Müller and vascular cells were largely spared. These lesions are ascribed to oligemia (ischemia) since the inner nuclear layer is a microscopic vascular watershed (boundary zone) between the choroidal and retinal circulations.

[Tissue cultures of normal and pathological corneal epithelia (author's transl)]

The changes of the cornea epithelium in the case of macular dystrophy are secondary. Those in lattice dystrophy are primary, the epithelial cells exhibiting the characteristics of cancer cells as well as hypertrophy of the lysosomal system and vacuolisation with autolysis.

Scanning electron microscopy, autolysis, and irradiation as techniques for studying small intestinal morphology

Examination of autolysed control mouse small intestine using scanning electron microscopy has revealed details of the connective tissue components of the mucosa. The cores of the villi are seen collapsed across the intervillous basin. Crypts of Lieberkuhn are seen as tubular channels stretching down from the intervillous basin. Sometimes the crypts are split in two by a connective tissue septum. The mouths of the crypts of Lieberkuhn are, in general, arranged in double rows between the single rows of villi. The ratio of number of crypts to numbers of villi was calculated as 5.01:1. This is close to the figure of 4.53:1, as quoted by Smith & Jarvis (1980) who used differential interference contrast microscopy to investigate the crypt to villus ratio. After radiation, the severe drop in the number of crypt mouths can be clearly seen by the combination of autolysis and scanning electron microscopy: the rows of crypt mouths between the villi have been lost, and many crypt mouths have been occluded by stromal tissue. The arrangement of the crypt mouths and the observation of mucosal abnormalities after irradiation have led to the postulation that cells leaving the crypt mouths move in a spiral manner towards and then up the villous surface: this postulated movement might imply an asymmetry in some properties of enterocytes. The use of scanning electron microscopy in conjugation with autolysis and irradiation has thus forced a critical re-examination of the relationships between crypts and villi.

Studies on the pathogenesis of ischemic cell injury. VI. Mitochondrial flocculent densities in autolysis

Flocculent densities in the matrix of mitochondria have become quite important in cell pathology since, when prominent, they indicate irreversible cell injury. The morphology and chemical nature of these flocculent densities have been studied in Kidney after various periods of autolysis in vitro in whole tissue samples and in isolated mitochondria. After 30 to 60 min of ischemia, flocculent densities were seen only occasionally and they were most prominent in samples subjected to mechanical damage during isolation. However, in 2- and 4-h samples numerous densities were seen. The size of the densities increased with time, being about 1,400 A in diameter at 4 h. Densities were also seen in mitochondria isolated in medium containing EDTA. They were seen only in the mitochondrial matrix, and could occasionally be found in condensed mitochondria. Small densities were generally round but larger one varied in shape and often appeared as aggregates of smaller densities. Digestion of the densities from water-soluble glycol methacrylate embedded samples was successful with pronase, but neither acid nor lipid solvents were effective. calcium or inorganic phosphate content of isolated mitochondria did not show an increase parallel to the occurrence of flocculent densities. The results suggest that the densities consist predominantly of protein and are probably formed through denaturation of proteins of the mitochondrial matrix and/or the inner membrane.

A study of the rate of cell depletion in solid tissue

The rate of disappearance of microneurons from the granular layer of the cerebellum of the rat during post-mortem autolysis was measured by image analysis of serial sections of perfusion preparations at various intervals during the first 24 hr after death. The cell population shows a logarithmic decrease during this period. The possible relation to cell death in disease and practical applications of this finding as a gauge of post-mortem interval are discussed.

[Morphological types of the changes in the myofibrils of cardiac muscle cells]

Light microscopy and electron microscopy examinations showed the changes in myofibrils to be a criterion of early stages of cardiomyocyte involvement. Proceeding from this, the main types of acute cardiomyocyte damage are distinguished: contractures (segmentary and subsegmentary), primary clump degeneration, intracellular myocytolysis and cytolysis. The best way to detect the state of myofibrils by light microscopy is to use polarization microscopy which diagnoses in sections acute metabolic damages and early stages of myocardial infarction, repeated and relapsing infarctions, fibrillation of ventricles. The utilization of polarization microscopy in pathological practice permits one to diagnose definitely the early stages of acute damages of the heart in cases of sudden and unexpected death.