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PubMed1988

Cyanide distribution in five fatal cyanide poisonings and the effect of storage conditions on cyanide concentration in tissue.

The cyanide distribution in five fatal cyanide poisonings was analyzed by the pyridine-pyrazolone method using a Conway diffusion cell. In order to study the effect of storage conditions on cyanide concentration in tissue samples, the cyanide concentrations were first measured immediately after collection of the samples at autopsy, then measured again after storage in a refrigerator (4 degrees C) or in a freezer (-20 degrees C) for periods ranging from 1 day to 3 weeks. Concentrations in all but three of the blood samples stored at 4 degrees C or -20 degrees C increased, with concentration ratios based on measurement made before and after storage ranging from 0.71 to 1.46. The concentrations in the liver, kidney, and brain samples either increased or decreased, with ratios of from 0.2 to 8.8. The concentrations in the stomach contents samples decreased rapidly at 4 degrees C, but hardly changed at all at -20 degrees C.

Adult↗
PubMed1992

Brain banking and the human hypothalamus--factors to match for, pitfalls and potentials.

The study of an increasing number of processes occurring in the human brain can be carried out on autopsy material. The availability of this material, whether fresh, frozen or fixed, makes it possible to develop methodologies for studying the neuroanatomical and neurochemical aspects of the human brain. It has also become possible in recent years to correlate functional changes with neurochemical changes and with neuroanatomical abnormalities in disease states. Some compounds and structures are damaged irreversibly within minutes after death and some brain components are known to disintegrate within seconds. This led to the widespread idea that autopsy material would not be suitable for basic research purposes and would not supply the necessary answers on the various fundamental questions regarding processes occurring in normal or diseased brain. However, from data published in recent years in which autopsy material has been routinely used, it becomes more and more evident that this is a misconception. There is an increasing number of reports based on the use of normal and pathological human brain tissue obtained by autopsies in spite of the fact that there is a worrying continuous decline in autopsy rate which causes serious concern among scientists world-wide (Anderson and Hill, 1989). It also became evident that when using the proper fixation procedures, sufficient structural integrity is retained in the tissue to allow morphological and morphometrical studies (Swaab and Uylings, 1988). Electron microscopic examination of synaptosomal preparations from post-mortem human brain showed them to be only slightly less pure than preparations from fresh tissue although there was some degree of damage (Hardy et al., 1982). Agonal state effects the stability of brain compounds and causes brain hypoxia. This again forms a tremendous difficulty for the study of human neurological and psychiatric diseases as one of the frequent causes of death is bronchopneumonia which leads to brain hypoxia and results in pronounced lactic acidosis. The Netherlands Brain Bank has succeeded to partly circumvent some of the serious problems encountered in providing human tissue for research by performing rapid autopsies with an average post-mortem delay of 2-4 h. This has become possible by a close collaboration of numerous nursing homes in Amsterdam and its vicinity and with the neuropathologists of the Free University in Amsterdam. We also measure the pH of the tissue as indicator of agonal state in order to reveal unsuitable specimens. The human hypothalamus contains various nuclei manifesting a wide variety of changes in different conditions.(ABSTRACT TRUNCATED AT 400 WORDS)

Aging↗
PubMed1979

Increased dopamine concentration in limbic areas of brain from patients dying with schizophrenia.

Dopamine, noradrenaline, glutamate decarboxylase (GAD) and choline acetyl-transferase (CAT) were measured in post-mortem brain samples from more than 50 patients dying with a hospital diagnosis of schizophrenia and an equal number of controls. GAD was measured in 14 different brain regions, and was significantly lower in both control and schizophrenia patients who died following a protracted illness. If GAD values from patients who died suddenly were compared, no significant differences were observed between the control and schizophrenia groups. There was also no differences between the CAT values measured in 13 different brain regions in the two groups. Noradrenaline values were not different in the two groups in most limbic areas or in the caudate nucleus, but were elevated in the schizophrenic group in nucleus accumbens and in anterior perforated substance. These differences were not, however, statistically significant. On the other hand dopamine concentrations in nucleus accumbens and in anterior perforated substance were significantly elevated (by 34 and 95 per cent, respectively) in the schizophrenia group as compared with controls, although dopamine values were not different in caudate nucleus, putamen, septal nuclei or amygdala. The finding of elevated concentrations of dopamine in certain areas of the limbic forebrain in schizophrenia is discussed in relation to current hypotheses of the involvement of dopamine in this illness, and the difficulties of determining whether the observed changes are related to chronic treatment with antischizophrenic drugs.

Brain Chemistry↗
PubMed2005

Ubiquitin immunohistochemistry suggests classic motor neuron disease, motor neuron disease with dementia, and frontotemporal dementia of the motor neuron disease type represent a clinicopathologic spectrum.

One of the characteristic pathologic changes in classic motor neuron disease (MND) is the presence of ubiquitin-immunoreactive (ub-ir) inclusions in the cytoplasm of lower motor neurons. In addition, cases of MND with dementia (MND-d) also have ub-ir neuronal cytoplasmic inclusions and dystrophic neurites in extramotor neocortex and hippocampus. Although this extramotor pathology is a highly sensitive marker for dementia in MND, similar changes are found in a subset of patients with frontotemporal dementia (FTD) with no motor symptoms (FTD-MND type). The purpose of this study is to more fully describe and compare the pattern of ub-ir pathology in these 3 conditions. We performed ubiquitin immunohistochemistry on postmortem tissue, representing a wide range of neuroanatomic structures, in cases of classic MND (n = 20), MND-d (n = 15), and FTD-MND type (n = 15). We found the variety of morphologies and the anatomic distribution of ub-ir pathology to be greater than previously documented. Moreover, the degree of overlap suggests that MND, MND-d, and FTD-MND type represent a spectrum of clinical disease with a common pathologic substrate. The only finding restricted to a specific subgroup of patients was the presence of ub-ir neuronal intranuclear inclusions in some cases of familial FTD.

Adult↗
PubMed1985

Post-mortem storage of tissue for X-ray microanalysis in pathology.

Possible alternatives to rapid freezing in liquid nitrogen of tissue for X-ray microanalysis of electrolytes at the cellular level were investigated. These alternatives might be used in cases where tissue becomes available for examination, e.g., at autopsy, but liquid nitrogen is not immediately available. Rat submandibular gland was used as a test tissue. Freezing of pieces of tissue in a conventional freezer at -80 degrees C or even at -20 degrees C retained the elemental distribution at the cellular level, and also retained the difference between a 'normal' and a 'pathological' (mimicked by an injection of a high dose of isoproterenol) situation. Storage of tissue in a refrigerator, or delaying the autopsy in anticipation of the arrival of liquid nitrogen is not recommended. Significant changes in the cellular ion content occurred if the tissue was left in the animal for 24h post-mortem.

Animals↗
PubMed1979

Influence of ante- and peri-mortem factors on biochemical and physical characteristics of turkey breast muscle.

The course of post-mortem breakdown of glycogen and ATP in turkey pectoralis major muscle was markedly influenced by several ante- and peri-mortem variables. Application of a proper stunning procedure was highly effective in preventing peri- and post-mortem muscle stress reactions. The physiological level of glycogen and ATP was not significantly affected by road transportation covering 260 km. Birds which rested for 24 hrs following transportation had lower glycogen and ATP levels at the moment of slaughter than non-rested birds. According to the changes in the rate and extent of post-mortem biochemical reactions, several meat characteristics such as water-holding capacity, colour, and tenderness were significantly changed. Furthermore, the results also indicate that turkey breast muscle is susceptible to a PSE-like condition as described in pork.

Adenosine Triphosphate↗
PubMed1997

When does the lung die? Kfc, cell viability, and adenine nucleotide changes in the circulation-arrested rat lung.

Lungs harvested from cadaveric circulation-arrested donors may increase the donor pool for lung transplantation. To determine the degree and time course of ischemia-reperfusion injury, we evaluated the effect of O2 ventilation on capillary permeability [capillary filtration coefficient (Kfc)], cell viability, and total adenine nucleotide (TAN) levels in in situ circulation-arrested rat lungs. Kfc increased with increasing postmortem ischemic time (r = 0.88). Lungs ventilated with O2 1 h postmortem had similar Kfc and wet-to-dry ratios as controls. Nonventilated lungs had threefold (P < 0.05) and sevenfold (P < 0.0001) increases in Kfc at 30 and 60 min postmortem compared with controls. Cell viability decreased in all groups except for 30-min postmortem O2-ventilated lungs. TAN levels decreased with increasing ischemic time, particularly in nonventilated lungs. Loss of adenine nucleotides correlated with increasing Kfc values (r = 0.76). This study indicates that lungs retrieved 1 h postmortem may have normal Kfc with preharvest O2 ventilation. The relationship between Kfc and TAN suggests that vascular permeability may be related to lung TAN levels.

Adenine Nucleotides↗
PubMed2003

Heat-mediated changes to the hands and feet mimicking washerwoman's skin.

If the palms of the hands and the soles of the feet of burnt bodies are not or only partially charred, whitish discoloration and wrinkled detachment of the epidermis is often observed. The findings are strongly reminiscent of the so-called washerwoman's skin, as seen after exposure to a moist environment for at least several hours. However, this is not to be expected after exposure to dry heat. What might be conceivable is a swelling of the skin due to the effect of the water used for fighting the fire. On the other hand this phenomenon is also observed in burnt bodies, which demonstrably have not come into contact with water, so that formation seems to be caused by a different mechanism. Moreover there are also histological differences between real washerwoman's skin and the pseudo-washerwoman's skin of fire victims. Whereas in genuine washerwoman's skin the stratum corneum is disaggregated and perinuclear vacuoles are found in the stratum germinativum, burnt bodies with pseudo-washerwoman's skin show detachment of the epidermis due to serum-filled blisters with elongation and palisade arrangement of the nuclei in the stratum basale. Consequently these changes agree with second-degree burns.

Adolescent↗
PubMedDate not supplied

[The diagnosis of fatty dystrophy of the liver in fresh, formalin-treated and putrefactive cadaveric material].

In the course of investigation it was stated that fat hepatic dystrophy can be diagnosed by biochemical method (lipid extraction by hexane). For al this the content of extracted lipids more than 20% of dry residue evidences about the presence of fat hepatic dystrophy which is confirmed by histological detection of lipid granules whose quantity is increasing from fat dystrophy I degree (lipid content amounts up to 30% of dry residue) to fat dystrophy III degree (lipid content is more than 40%). Formalin treatment doesn't produce significant changes in lipid content and doesn't prevent biochemical diagnosis of fat dystrophy of the liver. In case of putrefied liver lipid content is increased slightly but in all periods of putrefaction lipid content in the liver in case of fat dystrophy remains significantly higher than in controls. Biochemical method may be used in diagnosis of fat hepatic dystrophy and its degree not only on fresh and formalin-treated cadaveric material but also in case of markedly pronounced putrefactive changes when other methods are useless and this fact is of great value for medicolegal practice.

Body Water↗
PubMed1993

Experimental observations on adipocere formation.

Adipocere, "grave wax," is a waxy or greasy decomposition product formed by hydrolysis and hydrogenation of tissue fats. Once formed, it appears stable for extended periods. Adipocere has generally been considered to result from bacterial action, commonly in warm, damp, anaerobic environments. However, its frequency, rate of formation, factors affecting its formation and physical characteristics are not well defined. To study the frequency, time course, and effects of temperature and clothing on adipocere formation, we submerged human adipose tissue samples in aquaria under controlled conditions and conducted serial observations. Adipocere formed with high frequency, within a few months, in tissues submerged in warm tap water; similar changes took longer, 12 to 18 months in cold water submersion. Presence of clothing over the tissue appeared to accelerate adipocere formation.

Adipose Tissue↗
PubMed1984

[Microbial contamination of ABO antigens in bone tissue].

Fragments of human bones were stored in different media for two years and then expression of the ABO antigens was indicated. Simultaneously, microbiological investigations were performed. In almost all cases, different ABO substances were detected in putrefied and fresh bones taken from the same person. Blood group antigens found in putrefied bones were compared with serological activity of bacterium cultured from these tissues. Attempts were made to remove unspecific reactions. The authors assume that bacteria are responsible for nonspecific serological reactions, not only as a carrier of blood-group-like substances, but also as a source of enzymes responsible for changes in the structure of ABO antigens in putrefied bones.

ABO Blood-Group System↗
PubMed1980

Stability of the glutamate content of synaptosomes during their preparation.

The glutamate content of synaptosomal-enriched fractions is stable during the preparation and isolation of the organelles provided that the temperature of the preparation is maintained at 0--2 degrees C and that inorganic ions are not added to the homogenizing and centrifugation media. Consequently, drug-induced in vivo changes in the glutamate content of nerve endings should be reflected by the corresponding changes in glutamate levels of synaptosomes prepared from the brain tissue.

Animals↗
PubMed1978

The changes in activation of intracellular aspartate aminotransferase by pyridoxal 5-phosphate after cell death.

Aspartate aminotransferase activity was measured in plasma, in liver and in heart mitochondrial and cytoplasmic preparations from rats immediately after death and after a post-mortem interval of 15 h. No significant stimulation of activity on addition of pyridoxal 5-phosphate to the assay medium could be demonstrated in any preparations obtained immediately after death. Significant stimulation occurred in both cytoplasmic and mitochondrial preparations of liver and myocardium after a 15-h post-mortem interval, but not in plasma stored for the same period. It appears, therefore, that variations in the intracellular saturation of apoenzyme with coenzyme cannot account for the observed differences in activation of aspartate aminotransferase by pyridoxal 5-phosphate in sera from patients with myocardial infarction and liver disease. Changes in degree of saturation of apoenzyme seem to occur intracellularly after cell death or injury and before release into the circulation.

Animals↗