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Results for “Postmortem Changes”

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PubMed2004

Pathological entity of dementia with Lewy bodies and its differentiation from Alzheimer's disease.

We reclassified the pathological subtypes of dementia with Lewy bodies (DLB), based on both Lewy pathology and Alzheimer pathology, to clarify the pathological entity of DLB and the boundary between DLB and Alzheimer's disease (AD) in autopsied cases, using both pathological and immunohistochemical methods. DLB was classified as either limbic type or neocortical type according to the degree of Lewy pathology including Lewy bodies (LB) and LB-related neurites by our staging, and was classified as pure form, common form or AD form according to the degree of Alzheimer pathology including neurofibrillary tangles (NFT) and amyloid deposits by Braak staging. These combined subtypes were lined up on a spectrum, not only with Lewy pathology but also with other DLB-related pathologies including Alzheimer pathology, neuronal loss in the substantia nigra, spongiform change in the transentorhinal cortex and LB-related neurites in the CA2-3 region. In contrast, the Lewy pathology of AD did not meet the stages of Lewy pathology in DLB, and there were scarcely any similarities in other DLB-related pathologies between AD and DLB. In addition, the Lewy pathology of AD had characteristics different from that of DLB, including the coexistence rate of LB with NFT, and the immunohistochemical and immunoelectron microscopic findings of LB and LB-related neurites. These findings suggest that DLB is a distinctive pathological entity that can be differentiated from AD, although it shows some pathological subtypes.

Aged↗

PubMed2004

ABO genotyping by PCR-RFLP and cloning and sequencing.

A refined PCR-RFLP based method was established to genotype ABO blood groups. The main objective of this study was to make the techniques also suitable for working with degraded DNA. Specific primer design was carried out to choose fragments shorter than 200 bp as necessary in forensic and archaeological applications. Four fragments of exon 6 and 7 of the ABO gene were amplified and digested by in total 7 restriction endonucleases. Particular attention was paid to the base changes at nucleotide positions 261(delG), 297, 526, 703, 721, 771, 796 and 1060(delC) in order to distinguish the six common alleles A101, A201, B, O01, O02 and O03. Furthermore, this method also enables determination of seven of the less frequent alleles: A104, A204, Ax02, Ax03, O05, O06 and O07. The method was applied successfully to a series of blood samples with known phenotypes and genotypes as well as DNA extracted from a thirty year old blood stain and an ancient tooth sample. However, working with ancient DNA requires additional cloning and sequencing of the RFLP-typing results due to DNA post mortem damages such as deaminations, which could lead to false typing results.

ABO Blood-Group System↗

PubMed2006

Protein glutathionylation in human central nervous system: potential role in redox regulation of neuronal defense against free radicals.

Neuronal defense against free radicals is mediated primarily by the glutathione system. A cerebral defect of this system gives rise to the oxidative stress occurring in some neurological diseases. Glutathione provides a means of regulating protein function by glutathionylation, consisting of the formation of mixed disulfides between cysteines and glutathione. The glutathionylation of proteins, during both constitutive metabolism and oxidative stress, represents for the cell a mechanism to link physiological processes, and/or adaptive stress responses, to changes in intracellular redox states. In this study, we analyzed the topographic distribution of the protein glutathionylation normally occurring in human central nervous system. Constitutively glutathionylated proteins appeared uniformly distributed throughout all cortical layers of the cerebral and cerebellar cortex as well as throughout the gray matter of the spinal cord. The degree of immunocytochemical staining was clear in neurons, mild in oligodendrocytes, and weaker in astrocytes. The proteins preferentially glutathionylated were cytoskeletal proteins. Our results suggest a potential role of glutathionylation in the redox regulation of neuronal survival and in the control of axon/dendrite stability.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗

PubMed2004

Influence of post-mortem changes on DNA typing (D1S80, TH01, HLA DQA 1, and PM typing system): case studies for personal identification.

Between 1996 and 2002, we tested a total of 20 unidentified bodies for DNA typing. We describe here the relationships among detection rates achieved by four DNA typing systems (D1S80 typing, TH01 typing, HLA DQA1 typing, and PM typings), the post-mortem interval, types of specimens (bone, nail, and blood), post-mortem changes, and the site at which the corpse was found (indoors, outdoor, or in the sea). Detection rates for PM typings, HLA DQA1 typing, TH01 typing, and D1S80 typing in all cases were 94.7, 90.0, 73.7, and 50.0%, respectively. The success of the typings was highly influenced by the post-mortem interval. Using blood, almost all DNA types were detected, while the nail showed comparatively higher detection rates than bone. The detection rate decreased in order with indoor, outdoor, sea, and soil as the site at which the corpse was found. It is important to consider the specimen, the site at which the corpse was found, and the post-mortem interval to successfully achieve DNA typing.

Adult↗

PubMed2004

Influence of post-mortem delay and storage temperature on the immunohistochemical detection of antigens in the CNS of mice.

The aim of this work was to compare the results of histochemical and immunohistochemical methods using mouse brains which were fixed with various post-mortem delays and storage temperatures (at a constant 4 degrees C or 22 degrees C, or at gradually decreasing post-mortem temperatures, mimicking conditions of human corpse). We studied the effects of post-mortem delay on glial fibrillary acidic protein, extracellular matrix components to which Wisteria floribunda agglutinin binds, non-phosphorylated neurofilament H, synaptophysin, calbindin and nitric oxide synthase isoenzymes. At the light microscopic level first signs of post-mortem changes were detectable after 6 h. Glial fibrillary acidic protein was most affected by post-mortem delay since its immunoreactivity increased dramatically with increasing post-mortem delay. N-acetylgalactosamines-beta1 labeled lectin binding sites, calbindin and intraneuronal non-phosphorylated neurofilament H seemed to be stable up to 12 h post-mortem. Storage temperature influenced the NADPH-d activity and the content of synaptophysin immunoreactivity to higher degree than all of the other parameters. We found only marginal differences of alterations comparing neocortex, hippocampus and corpus callosum. Our results indicate that different antigens are affected differently by the ongoing catabolic processes during post-mortem delay.

Animals↗

PubMedDate not supplied

Effusion cytology of hepatocellular carcinoma.

OBJECTIVE: To evaluate effusion cytology on routine smears in patients with hepatocellular carcinoma. STUDY DESIGN: Filed smears from 106 patients with autopsy-proven hepatocellular carcinoma were retrospectively reviewed for the presence of malignant cells. Morphologic patterns, as well as immunochemical reactivity for a panel of antibodies, were analyzed when feasible. RESULTS: Malignant cells were identified in 10 cases of ascites and 1 of pleural fluid. Positive smears were variably cellular, with paucicellular, round or linear aggregates of polygonal cells. The cytoplasm was usually evident and very stainable. The nuclei were hyperchromatic or vesicular, with inconspicuous nucleoli. Reactive changes were frequent. Malignant cells were positive for keratins (7/8) and erythropoietin (4/8) and negative for carcinoembryonic antigen (0/8). Concomitant cirrhosis was present in 103 cases (97.1%); all the noncirrhotic cases had malignant cells identifiable in the effusion. Antemortem clinical diagnosis of malignancy was made in 59 cases (55.7%); cytology was the only source of the morphologic diagnosis in most of them. CONCLUSION: These results indicate that although the yield of hepatocellular carcinoma in effusion cytology is limited, it may be important in the initial assessment of the disease, given the ineligibility of most patients for invasive procedures and the equivocal features of instrumental investigations. Immunocytochemistry may further assist in differentiating doubtful cases.

Adult↗

PubMedDate not supplied

The influence of putrefactive changes on the determination of Paraquat in autopsy materials.

This paper describes how the putrefactive changes in a cadaver will influence the determination of Paraquat in autopsy material. The carcasses of rats that had been given large doses of Paraquat and subsequently killed by cervical dislocation, were left at room temperature for up to seven days. Samples of stomach, caecum and liver were removed for the colorimetric determination of Paraquat with sodium dithionite following extraction on a Dowex 50W-4 column. Paraquat recovered from the stomach and caecum showed a decrease with time after death with the rate of decrease being greater in the caecum samples. However, the concentration of Paraquat in the liver increased for three days and then began to decrease gradually. The possible causes of these variations in Paraquat recovery are discussed. The findings appear to demonstrate the value of Paraquat determination even in samples from material that is in a state of advanced putrefaction.

Animals↗

PubMed1984

Studies of gamma-glutamyltransferase activity in the brain tissue post mortem.

Our experiments showed that the activity of gamma-glutamyltransferase (gamma-GT) did not remarkably change in homogenates of mouse, rat, and bovine brains during the first four days post mortem. In the course of that period, the brain microvessels also retained their gamma-GT activity. gamma-GT of microvessels from bovine brain cortex, solubilized with sodium deoxycholate, was eluted in the void volume Vo when chromatographed on a Sephadex G-200 column with the detergent Triton X-100. In human post mortem brains, the specific activity of gamma-GT in choroid plexi was found to be about five times higher than that in the cerebral cortex, white matter, basal ganglia, pons, and cerebellum but about four times lower than that in the microvessels obtained from the studied brain regions. Our findings suggest that it is possible to study the components of the blood-brain barrier on material from deceased subjects.

Animals↗

PubMed1991

Reduced basal and stimulated (isoprenaline, Gpp(NH)p, forskolin) adenylate cyclase activity in Alzheimer's disease correlated with histopathological changes.

Cyclic adenosine monophosphate (cAMP) is an adenylate cyclase borne second messenger involved in basic metabolic events. The beta-adrenoceptor sensitive adenylate cyclase was studied in post-mortem hippocampi of controls and Alzheimer patients. Virtually identical subsets of each hippocampus homogenate were stimulated by 100 mumol isoprenaline, Gpp(NH)p and forskolin, respectively, in presence of an ATP-regenerating system. The determination of cAMP formed was carried out by means of a radioassay. The observed significant 50% reduction in basal as well as in stimulated adenylate cyclase activity in Alzheimer's disease is negatively correlated with semiquantitative evaluations of amyloid plaques (P less than 0.05) but not with neuritic plaques, neurofibrillary tangles or neuropil threads. This reduction in enzyme activity is obviously not due to simple cell loss alone. It is likely that the crucial point of the observed functional disturbance is at the level of the catalytic unit of the adenylate cyclase, since the same degree of reduction is maintained at all steps of the signal cascade.

Adenylyl Cyclases↗

PubMed1980

Effect of post-mortem electrical stimulation on ovine sarcoplasmic reticulum vesicles.

Sarcoplasmic reticulum (SR) vesicles from ovine skeletal muscle were iodinated with the use of immobilized lactoperoxidase to determine the location of proteins in the membrane and to observe any changes resulting from post-mortem electrical stimulation. The labelling pattern of the non-stimulated SR preparations was esentially the same as that observed previously for white muscle SR of rabbit. Most of the membrane protein were labelled, except for the high-affinity calcium-binding protein. Electrical stimulation, however, resulted in an increased labelling of calsequestrin suggesting that this protein is more exposed as a result of such treatment. Certain activities of the adenosinetriphosphatase were affected by electrical stimulation. Both the steady-state concentration of phosphoenzyme and the ATP in equilibrium Pi exchange reaction were significantly reduced by electrical stimulation. It is not known if this alteration in the membrane is responsible for the reduced activity of the SR and thus the greater rate of post-mortem pH in electrically stimulated muscle.

Animals↗

PubMed2004

Spinal cord molecular profiling provides a better understanding of amyotrophic lateral sclerosis pathogenesis.

Research efforts in amyotrophic lateral sclerosis (ALS) have not yet provided a comprehensive explanation of the disease pathogenesis, which is emerging as a complex interaction between multiple factors. Gene expression studies traditionally based on single mRNA specie analysis have recently progressed to allow entire transcriptional profiles of affected tissues to be obtained through array-based methods. This experimental approach has significantly improved our understanding of the molecular changes occurring in ALS, although its limitations in the detection of low-abundance transcripts in tissues with a high level of complexity are becoming increasingly recognized. In this paper, experimental findings based on an expression study in post-mortem spinal cord from sporadic ALS individuals will be discussed in light of recently published data using array analysis in an animal model of the disease. Previous expression data obtained using conventional techniques are also compared. Through the analysis of the information arising from ALS post-mortem and animal model tissues studies, we have identified a pattern of molecular events in which factors implicated in the immune response, cytoprotection and growth-differentiation are differentially regulated in a time-dependent way from early to advanced stages of disease progression.

Amyotrophic Lateral Sclerosis↗

PubMed1980

Post-mortem modifications of the ependyma of the lateral ventricular wall.

The ependymal lining of the lateral ventricles of the brain of rats, rabbits, and man was investigated at several times after death. In contrast to control material that was fixed by the aldehyde perfusing method, the following post-mortem (p.m.) changes were found: (1) Cytoplasmic protrusions of ependymal cells appear 15 min p.m. They are present up to several hours after death. (2) The formation of these protrusions causes the tufts of cilia to clump together and later to become integrated within the ependymal cell. This may simulate an unciliated surface. (3) Small porelike holes, which are present 15 min p.m. in the ependymal cell membrane, enlarge and in later stages produce a meshwork of fibers instead of a closed ependymal lining. (4) TEM observation shows that ependymal cells are separated from each other very soon after death by intercellular gaps. Cell junctions between ependymal cells resist separation over a longer p.m. period. In animal or human material that is fixed at any time after death, such modifications have to be considered very critically. In human p.m. autopsy material they are mostly the expression of a p.m. alteration.

Animals↗

PubMedDate not supplied

Downregulation of neuronal cyclooxygenase-2 expression in end stage Alzheimer's disease.

Nonsteroidal anti-inflammatory drugs (NSAIDs) appear to delay the onset of Alzheimer's disease (AD). NSAIDs inhibit cyclooxygenase (COX), of which two isoforms exist. We report decreased neuronal COX-2 expression in AD subjects relative to nondemented controls using qualitative analysis of COX-2 immunoreactivity and quantification of COX-2 positive neurons in different hippocampal subfields. These changes also occurred in subjects with other dementia and thus may not be disease specific. The proportion of COX-2 positive neurons decreased in subjects with clinical dementia rating (CDR) 5 but not CDR 4, suggesting that this was a late event in the course of the disease. Furthermore, COX-2 was not preferentially associated with paired helical filament immunoreactivity, a marker of neuronal pathology. COX-2 immunoreactivity was also observed in astrocytes and cerebrovasculature. Indeed, the density of COX-2 immunopositive astrocytes was increased in AD temporal cortex. Based on our findings, it is unlikely that neuronal COX-2 contributes to pathology in end stage AD; however, COX-2 in other cell types may participate in the inflammation-related response associated with the disease.

Aged↗

PubMed1994

Rapid translocation of cytosolic Ca2+/calmodulin-dependent protein kinase II into postsynaptic density after decapitation.

The postsynaptic density (PSD) fraction prepared from rat forebrains frozen with liquid nitrogen immediately after dissection (within 30 s after decapitation) contained major postsynaptic density protein (mPSDp), alpha subunit of Ca2+/calmodulin-dependent protein kinase II (CaMKII) at a level of merely 2.7% of the total protein. The content of the protein in the fraction was increased to approximately 10% by placing the forebrains on ice for a few minutes. Accumulation, but to a lesser extent, of the protein after placement was also observed in the particulate, synaptosome, and synaptic plasma membrane fractions with its concomitant decrease in the cytosolic fraction. The distribution change may be translocation of the protein, because the amounts of the losses of the protein in the cytosolic fraction were balanced by the gains in the particulate fractions. By translocation, CaMKII became Triton X-100 insoluble and partially inactivated. The amount of CaMKII transferred from the cytosol to particulate fractions at 0 degrees C was about the same as that contained in the conventional PSD fraction. Furthermore, the thickness of the PSD was increased by the treatment of the forebrains at 37 degrees C, by which the content of CaMKII alpha in the PSD fraction was increased to twofold. These results suggest that most of the CaMKII alpha subunit associated with the PSD fraction (mPSDp) is translocated from cytosol after decapitation. We also showed similar translocation of CaMKII beta/beta'.

Amino Acid Sequence↗

PubMed1984

Connectin content and its post-mortem changes in fish muscle.

Connectin was isolated from fish dorsal myofibrils by an SDS-gel filtration method and estimated to account for approximately 13% of the total myofibrillar proteins. There was no significant difference in the amount of connectin among seven fish species but rabbit skeletal myofibrils contained a slightly higher content (16%) of connectin. The high molecular weight connectins from carp and rabbit both showed a doublet band, consisting of bands 1 and 2, on SDS-polyacrylamide gel electrophoresis using a large-pore gel. However, rabbit band 1 (a component of the connectin doublet) was found to migrate more slowly than carp band 1. During post-mortem ageing of the muscles, it was observed that the band 1 component rapidly disappeared with a concomitant increase in band 2 component and then the band 2 component was transformed slowly into faster migrating components. These results suggest that post-mortem ageing has qualitatively similar effects on the submolecular compositions of carp and rabbit connectins. However, the apparent rate of disappearance of the band 1 component was considerably higher in carp muscle than that in rabbit muscle.

Animals↗

PubMed2002

Identification of protein degradation during post-mortem storage of pig meat.

Eighteen proteins and peptides that were found to change post-mortem in Longissimus dorsi from pig muscle were identified by the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The 18 peptides originate from 9 different proteins including the 3 structural proteins (actin, myosin heavy chain, and troponin T) and the 6 metabolic proteins glycogen phosphorylase, creatine kinase, phosphopyruvate hydratase, myokinase, pyruvate kinase, and dihydrolipoamide succinyltransferase. The molecular weight and estimated sequence length of the identified spots show that these fragments result from proteolytic activity in meat. Identification of the parent proteins and the enhanced post-mortem appearance of the degradation products make these specific peptides good candidates for meat quality markers, and further studies of these specific fragments will lead to a better understanding of the proteolytic activities involved in the post-mortem conversion of muscle to meat.

Animals↗

PubMed2006

Taphonomy of child-sized remains: a study of scattering and scavenging in Virginia, USA.

Child-sized pig carcasses (Sus scrofa) were placed in surface deposit and buried scenarios in a wooded area of Virginia from May 1998 through December 2000, to examine the taphonomic effects of decompositional changes, predator scavenging, and the extent of remains scattering. Changes were observed through on-site examination, charting of remains, and recorded video imaging. Analysis of data revealed that utilization of corpses as food sources by vertebrates was dependent upon invertebrate colonization. Vertebrates avoided feeding on the corpses while invertebrate colonization was active, and would feed before invertebrates successfully colonized a corpse, or would wait until the invertebrate populations migrated away from the corpse. Among vertebrates, there was no apparent succession order for the animals utilizing the remains as a food source. Different vertebrates would feed at different times based upon diurnal or nocturnal predilection. Analysis noted an accidental cooperative relationship between the invertebrates and vertebrates scavenging on the corpses. Certain vertebrates gained access to the internal tissues by utilizing openings in the corpses caused by invertebrate and other vertebrate scavenging. Alternately, carrion-frequenting insects were afforded access to previously inaccessible colonization sites as a result of scavenging vertebrate activities.

Animals↗

PubMed2005

Time-course changes in the expression of heme oxygenase-1 in human subcutaneous hemorrhage.

To determine the time-course of human subcutaneous hemorrhage, heme oxygenase (HO)-1 expression and macrophage infiltration were observed using an immunohistochemical technique and semiquantitative analysis. The number of immunoreactive cells and the number of all infiltrating cells of each microscopic field were counted, and the ratio of the former to the latter was calculated as the positive cells ratio. An increase in the HO-1-positive cells ratio was observed starting at 3 h after injury, and the maximum ratio was observed 3 days after injury. The pattern of the increase in the macrophage ratio was similar to that of the HO-1-positive cells ratio in the early period after injury. Observation of serial sections revealed that the expression of HO-1 in the cells corresponded to the localization of macrophage. The present results suggest that the determination of HO-1 expression, as derived from macrophages, might be useful for the estimation of the time-course of subcutaneous hemorrhage.

Adolescent↗