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At least 685 records · Page 38Linked to original sources
PubMed1992

Early and late meningeal reaction to trauma after long-term brain death.

We examined histologically the meninges adherent to traumatic lesions of a patient with brain death sustained for 101 days and observed both early and late reactions of wound healing at the same site of the dura mater. Some parts of the dura mater were thick and histological examinations revealed formation of new vessels and fibrosis with strong positive reaction for iron and fat staining. We also observed fresh haemorrhage and some cell infiltration in the dura and fresh haemorrhage in a small piece of necrotic brain tissue adhered to the dura mater, while other areas of the brain tissue were completely necrotic, enabling the sites of head injury to be localised. These observations suggested that the blood flow in the dura mater fluctuates due to a change of microenvironment, which probably causes repeated secondary petechial haemorrhages in the dura and its adherent necrotic brain tissue, even 101 days after brain death.

Brain Death↗
PubMed1992

Post-mortem changes in the normal rat carotid body: possible implications for human histopathology.

The carotid bodies in experimental animals contain only one variety of type I cells whilst in the human organ three varieties of this cell type have been described. We have examined the effects of post-mortem change on the structure of the type I cell of the rat carotid body. When the organ is examined immediately after death of the animal all of the type I cells exhibit similar morphology. With increasing delay in fixation of the tissue the type I cells undergo autolytic changes. Within 2 h of death the nuclei become hyperchromatic and the cytoplasm exhibits an increasing eosinophilia. In carotid bodies fixed 4 h post-mortem a further type I cell variant is seen in which the nucleus lacks a chromatin pattern and become pyknotic. We believe that previous descriptions of three varieties of type I cells in the human carotid body are based upon a description of post-mortem change. Furthermore, in any study of this highly oxygen dependent tissue it is essential that due account be taken of the delay between death and fixation.

Animals↗
PubMed1991

Simultaneous observation of catecholamine, serotonin and their metabolites in incised skin wounds of guinea pig.

In order to examine the vital reaction in wounds, catecholamines, serotonin (5-HT) and their metabolites in the incised skin wounds of guinea pigs were analyzed simultaneously by high-performance liquid chromatography (HPLC) using electrochemical detection (ECD). The principal changes in the levels of these compounds in vital wounds were as follows: a considerable decrease in norepinephrine (NE) content was observed 12-24 h after injury which persisted to at least 7 days. 3,4-Dihydroxyphenylacetic acid (DOPAC) decreased slightly for up to 30 min and then showed no significant difference compared with postmortem levels. Epinephrine and dopamine were barely detected by the HPLC-ECD method employed. 5-HT concentrations which showed an increase up to 24 h showed maximum levels 800 microns from the wound edge at 10 and 30 min after injury. 5-Hydroxyindoleacetic acid (5-HIAA) was significantly higher than the postmortem level over almost the entire period of these experiments. A 5-HIAA content of at least twice the postmortem level was observed 800 microns from the wound edge of a 10-min-old vital wound. Therefore, 5-HIAA is a likely candidate as a new marker for evaluating the vital reaction in wounds. The vital characteristics of NE, DOPAC, 5-HIAA and 5-HT in 10-min-old wounds persisted for up to 12 h at room temperature after death. These results suggest that the HPLC-ECD method used here is very useful for simultaneous examination of the vital reaction in wounds from the earliest to the later stages of the wound-healing period.

Animals↗
PubMed1996

Evaluation of hypostasis using a colorimeter measuring system and its application to assessment of the post-mortem interval (time of death).

Hypostasis was measured in 93 cadavers using a tristimulus colorimeter in order to investigate its relationship with the time of death. The intensity (lightness) of the hypostasis in each case was measured over a period of 4 h and the rate of change in lightness derived. When examined against the time of death, it was found that there was a good correlation between the two. Namely, that the rate of change of lightness (and it can be inferred that this represents displaceability) decreases as the post-mortem period increases. The shift in hypostasis was particularly marked in the first 12 h and decreased thereafter. However, hypostasis could be useful for time of death estimation for up to 48 h. After this time, the degree of change was small or non-existent and by 72 h hypostasis had become fixed in the majority of cases, within our measuring period of 4 h.

Adult↗
PubMed2002

The assessment of post mortem structural changes in the human epidermis.

The structure of epidermis and appearance of keratinocytes is described in intact skin specimens from human corpses stored after death under refrigeration. Two groups of alterations can be identified depending on the epidermal layer. In the spinous layer, the cells are characterized by crescent-shaped nuclei surrounded by a hollow area. The number of such cells increases significantly each day during the first 8 days post mortem (dpm), and their frequencies follow respective regression equations, so as to enable the post mortem time estimation with one day accuracy. In the basal layer, distorted, balloon-shaped cells with pycnotic nuclei appear, which with the lapse of time are forming groups, and eventually the epidermis in those places separates from the dermis. The presence of both described changes seems to indicate whether the skin sample was obtained from the living organism or after the death.

Adolescent↗
PubMed1989

[Ethanol distribution in body fluids in the human from a forensic medicine viewpoint. Prepared as an initial study].

A comparative study of ethanol concentration was performed in body fluids of corpses. One group consisted of dead bodies without sings of putrefaction (160 cases), and the second group included 60 cases with advanced putrefaction. In the first group the concentration of ethanol in blood, cerebrospinal fluid, vitreous humour, inner ear fluid and urine (in 147 cases) was determined, whereas in the second group blood and inner car fluid was examined. The observed differences in ethanol distribution in examined materials were the basis for the development of models of ethanol distribution in the body. Distinct relations between the ethanol concentrations in blood and other fluids allow to assess the blood ethanol concentration on the basis of examination of other materials. It is important in the cases when blood is not available and putrefactional changes of blood can be a reason of misinterpretations. Such assays appear to be useful in forensic assessment of drunkness.

Adolescent↗
PubMed1986

[Determination of monoamines and 10 of their metabolites in the brain and heart of the rat by high-pressure liquid chromatography with electrochemical detection].

The adequate parameters for simultaneous determination of more than 10 monoamines, their precursors and metabolites (noradrenaline, 3-methoxy-4-hydroxyphenylglycol, 3,4-dihydrooxyphenylglycol++, vanylylmandelic acid, normetanephrine, adrenaline, metanephrine, dopamine, 3-methoxytytramine, 3,4-dihydroxphenylacetic acid, 3,4-dihydroxyphenylalanine, 5-hydroxytryptophane, 5-hydroxyindolacetic acid) by liquid chromatography with electro-chemical detection were suggested for the rat brain and heart. The influence of reserpine, iproniazid, and imipramine on the content of the changes of monoamines and their metabolite levels in the rat brain and heart were also investigated.

Amines↗
PubMed1977

The pathogenesis of acute selective necrosis of the granular layer of the human cerebellar cortex.

PH determinations by means of a sturdy, spear-electrode inserted in the cerebellar tissue immediately after necropsy were carried out in 60 patients suffering from different disorders and dying in hospital, and from 25 individuals killed instantly by violent accidents. A correlation was found between the presence of NGL and low pH levels in the cerebellum (average pH 5.56); subjects without NGL changes showed an average pH OF 6.08. No correlation was found between the pH levels and the time after death, or between pH and any specific disease. The so-called acute selective necrosis of the granular layer of the human cerebellar cortex (NGL), is considered from the present studies to be a phenomenon of postmortem origin. Its relationship to certain specific diseases can be explained by the fact that in these conditions there is a higher postmortem acidity, known to promote autolysis.

Aged↗
PubMed1997

The shrinkage of the human brain stem during formalin fixation and embedding in paraffin.

On the basis of measurements on fresh human brains (n = 33), changes in size of the brain stem which occurred as a result of formalin fixation and embedding in paraffin were quantified and converted into linear correction factors. In contrast to the known changes in the cerebrum, the formalin fixation did not result in a 'positive formalin effect', but left transverse values unchanged and led to decreases in longitudinal distances of 1-8% (correction factors: 1.01-1.09). Further embedding resulted in a linear shrinkage of 11-12% (correction factors: 1.12-1.13) transversely and 17% (correction factor: 1.21) longitudinally, which was smaller than the shrinkage in the cerebrum of 11-25% (correction factors: 1.13-1.34) reported in the literature. The examinations revealed changes in the brain stem caused by the total fixation and embedding process different from those of the cerebrum.

Adolescent↗
PubMed1984

Serotonin receptor changes in dementia of the Alzheimer type.

Serotonin receptors were assessed in post-mortem brains of control and Alzheimer-type dementia (ATD) patients using ligand binding techniques. Differential losses of serotonin S1 and S2 receptors were present in neocortex, hippocampus, and amygdala of ATD patients, whereas no significant changes were observed in basal forebrain and basal ganglia. Losses of S1 receptors were significantly age-related in the ATD group, suggesting they occurred at a later stage of the disease process. Losses of S2 receptors were considerably greater (with a reduction to 35% of control in temporal cortex) and were not age-related in ATD. Significant correlations were observed within the ATD group between S2 receptor binding and somatostatin immunoreactivity in temporal and frontal cortices. Thus the loss of S2 receptors in ATD may be a relatively early change in the disease process, and may precede the changes in ascending serotonergic neurones.

Aged↗
PubMedDate not supplied

[Changes in kidney glomeruli in relation to the time of death].

The estimation of the time of death is until today a medico-legal problem only partially solved. We have studied, by scanning electron microscopy, post-mortem changes of human glomerula in anatomical structures (capillary endothelium) and in times of death (9-15 hrs) barely considered until now. We observed changes reported by other Authors (altered microvillus morphology, podocyte surface blebs, swelling and retraction of pedicles) as well as interesting changes of capillary endothelium which is still present, even if clearly altered 9 hrs post-mortem, whereas it is no more visible 15 hrs after the death.

Animals↗
PubMedDate not supplied

[The diagnosis of myocardial fatty dystrophy in putrefaction-altered cadaveric material (biochemical and histological studies)].

The biochemical method of lipid level assessment by their hexane extraction permits a judgement on the presence of obesity (fatty dystrophy) in the myocardium in drastic putrefactive changes in the corpse, when other methods are useless. Use of this method in cases with putrefactive changes will help in many cases to decide the problem on the possible 'cardiac' mechanism of death.

Adult↗
PubMed2004

Familial frontotemporal dementia: a report of three cases of severe cerebral atrophy with rare inclusions that are negative for tau and synuclein, but positive for ubiquitin.

We describe the brain autopsy findings from three of five siblings who suffered dementia with clinical diagnoses including Alzheimer's, Parkinson's, and Pick's disease. Five other living siblings appear unaffected. All of the autopsied brains showed severe atrophy (brain weights 613, 641, and 750 g) of the frontal and temporal lobes, and to a slightly lesser extent of the parietal lobes, while the occipital lobes were relatively preserved. The substantia nigra showed marked neuronal loss with gliosis. No ballooned neurons, neurofibrillary tangles, neuritic plaques, Pick bodies, or Lewy bodies were found in these brains. Immunohistochemistry for tau protein failed to reveal neuronal or glial inclusions, and normal tau protein was found in a separate Western blot study [Adamec et al. (2001) Neurosci Lett 315:21-24]. Rare neurons with ubiquitinated cytoplasmic inclusions were scattered in the neocortex and hippocampus. The overall pathological features were consistent with a severe form of frontotemporal dementia (FTD) with involvement of the substantia nigra. Whether the rare ubiquitinated inclusions are sufficient to classify these cases as FTD with motor neuron disease type inclusions but without motor neuron disease, or FTD dementia lacking distinctive histological features remains unclear. The features of lobar circumscribed atrophy without Pick bodies and without ballooned neurons, however, are consistent with Pick disease group C in the Constantinidis classification [Constantinidis et al. (1974) Eur Neurol 11:208-217].

Aged↗
PubMed2004

Application of proteome analysis to seafood authentication.

Part of our work aims at studying the modifications that proteins suffer in foods and use them as markers to estimate the origin and history of the product. Proteomics is a powerful approach to do this: comparison of the two-dimensional (2-D) maps of the intact and treated samples would permit to identify marker spots so that in the future it may be possible to estimate the treatment a foodstuff has suffered by examining its 2-D protein map or just the selected markers. This work summarizes some of our previous studies showing the application of proteomics to the (i) identification of species and muscle tissues, (ii) characterization of post-mortem changes in arctic and tropical species, and (iii) study of the effect of some additives during the processing of fish muscle.

Animals↗
PubMed1984

Cyclical phenomena occurring during the maturation of the enamel of rat incisor teeth. Their manifestation during drying.

A pattern of obliquely oriented bands has been demonstrated at the surface of the maturation zone enamel of freshly dissected rat incisor teeth as they dry. This pattern, of which there is no evidence in the fresh, wet, or completely dry teeth, consists of up to 4 or 5 pale grey, translucent lines separated by wider, whiter, more opaque bands and has been shown to correlate directly with a similar pattern seen on the same teeth after staining with toluidine blue and previously described as the maturation cycle banding pattern (Boyde and Reith 1982). A second pattern comprised of much more closely spaced bands is also described. In this pattern, which again correlates with a similar pattern seen after toluidine blue staining, translucent and opaque bands cross the maturation zone more transversely and have a width of about 200 microns, approximating to 8 h tooth growth. It is postulated that these banding patterns reflect alternately different drying rates of the maturation zone enamel and that they may correspond to cyclical changes in the hydrophobicity and hydrophilicity of enamel matrix both on a daily basis and on a larger time scale.

Animals↗