bromochloroacetic-acid and Autolysis

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.

Topics: Actins; Aged; Autolysis; Carcinoembryonic Antigen; Cell Membrane; Cytoplasm; Female; Histocytochemistry; Humans; Immunohistochemistry; Keratins; Male; Microscopy, Electron; Middle Aged; Mitochondria; S100 Proteins; Sweat Glands; Time Factors

Immediate fixation or snap freezing of tissue is ordinarily done to maximize antigen preservation for immunocytochemistry; however, delay in tissue allocation or spontaneous lymph node infarction can render tissue suboptimal for immunostaining. To test the effects of tissue autolysis/necrosis on the preservation of various lymphoid, epithelial, and mesenchymal markers, two lymph nodes (one with reactive lymphoid hyperplasia and one with metastatic ductal breast carcinoma) were evaluated for immunocytochemically demonstrated antigen preservation at 0-, 4-, 8-, 12-, 24-, 48-, and 72-hour intervals of autolysis at 37 degrees C. All specimens were stained by frozen section and formalin-fixed paraffin section immunocytochemical reactions with antibodies against CLA (CD45), UCHL-1 (CD45RO), L-26, kappa, lambda, anti-epithelial keratins (AE-1 and AE-3), epithelial membrane antigen, and vimentin. Frozen sections were additionally stained for Leu-1 (CD5), Leu-2a (CD8), Leu-3a+b (CD4), Leu-4 (CD3), and Leu-14 (CD22). The most resilient lymphoid antigen preservation was observed with CLA and UCHL-1, both exhibiting immunoreactivity at 72 hours in both frozen and fixed preparations. L-26 showed similar reactivity in frozen sections, but detectable antigen was observed only up to 24 hours in formalin-fixed tissue. Leu-2a proved to be the most labile antigen, persisting for only 12 hours in frozen sections. The epithelial markers epithelial membrane antigen and AE-1 exhibited excellent antigenic preservation in both frozen and fixed preparations; AE-3 persisted well in frozen section but was not demonstrated in fixed tissue. Vimentin immunoreactivity was vastly superior in frozen, as compared with fixed, tissue sections. Most antigens showed remarkable preservation despite morphologic degradation; however, differential antigenic resilience was demonstrated. Knowledge of this variation in antigen decay is critical for evaluation of immunoperoxidase phenotypic studies of autolyzed or necrotic tissue.

Topics: Antigens; Antigens, CD; Autolysis; Biopsy; Humans; Immunohistochemistry; Keratins; Lymph Nodes; Membrane Glycoproteins; Mucin-1; Necrosis; Tissue Preservation; Vimentin

Evidence is reviewed in support of the hypothesis that immature unkeratinized fetal skin must be present if bovine fetal mummification is to occur. The reduction in fetal and amniotic fluid is considered to be the result of intrafetal (fetal death) or prefetal (caruncular damage) effects on the normal net fluid flow from the maternal circulation through the fetal circulation and then across the fetal skin into the amniotic cavity. As the skin is keratinized permeability is reduced drastically thus limiting fluid loss from the fetus.

Topics: Amniotic Fluid; Animals; Autolysis; Cattle; Female; Fetal Death; Keratins; Maternal-Fetal Exchange; Ossification, Heterotopic; Permeability; Postmortem Changes; Pregnancy; Skin; Skin Physiological Phenomena

Topics: Animals; Autolysis; Cell Aggregation; Cells, Cultured; Desmosomes; Ear; Guinea Pigs; Keratins; Lysosomes; Microscopy, Electron; Microscopy, Phase-Contrast; Motion Pictures; Skin; Time Factors

Topics: Acid Phosphatase; Animals; Autolysis; Biological Transport; Chromatophores; Guinea Pigs; Histocytochemistry; Humans; Hydrolases; Keratins; Lysosomes; Microscopy, Electron; Peroxidases; Phagocytosis; Pinocytosis; Proteins; Skin Absorption; Species Specificity

Topics: Autolysis; Biological Transport, Active; Epithelium; Female; Fetus; Glycogen; Hair; Humans; Keratins; Morphogenesis; Phagocytosis; Pregnancy; Sebaceous Glands