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Biomedical subjects

B F Trump

Publications and source records attributed to B F Trump.

At least 325 records · Page 18Linked to original sources
PubMed1975

Studies on the modification of the cellular response to injury. II. Electron microscopic studies on the protective effect of acidosis on anoxic injury of Ehrlich ascites tumor cells.

Extracellular acidosis (ph 5.9 to 6.5) was found to be significantly retard the subcellular response of Ehrlich ascites tumor cells (EATC) to anoxic injury. The cells initially showed a reversible stage of cell injury with diffuse mitrochondrial condensation and swelling of endoplasmic reticulum (ER) at pH 7.9 by 1 h, while by 3 h at this pH all cells showed high amplitude and intramatrical flocculent densities of mitochondria, and fragmentation of membrane systems. At pH 7.4 cells were normal at 15 min., the mitochondria were condensed as above by 1 h, some cells still showed condensed mitochondria and dilated ER while others showed high amplitude swelling of mitochondria by 3 h and all cells showed irreversible changes by 4 h. At pH 5.9 to pH 6.5 mitochondria remained condensed until 3 h and only by 6 h did some cells show high amplitude swelling, whereas most cells showed persistent mitrochondrial condensation. Not until 8 h did all cells show high amplitude swelling of mitochondria. Furthermore, ultrastructural differences in the pattern of necrosis were seen at the lower pH values consisting of greater density of the cell sap, irregularly dispersed flocculent densities in apposition to fragmented cytoplasmic membranes and in mitochondria, and more prominent persistent clumping of nuclear chromatin.

Acidosis↗
PubMed1975

Mitochondrial changes, ion and water shifts in the cellular injury of ehrlich ascites tumor cells.

Cellular injury was produced in Ehlrich ascites tumor cells by an inhibitor of the function of the cell membrane [10(-3M) parachloromercuribenzenesulfonic acid (PCMBS)] or by inhibitors of respiration (10(-4M) Antimycin A), glycolysis (10(-4M), iodoacetic acid, IAA), oxidative phosphorylation (10(-3M) 2,4 dinitrophenol, DNP) or by combinations of these in a medium with or without glucose. The contents of Na+, K+, Ca++, Mg++ and intracellular water in the treated cells and controls were correlated with the percentages of ultrastructural changes in the mitochondria of the cells. A moderate negative correlation (r = -0.66) was observed between K+ content of the cells and the condensation of mitochondria in selected experiments where mitochondrial swelling had not yet started. A moderate positive correlation (r = 0.44) was observed between mitochondrial condensation and Na+ content of the cells in the same experiments. K+ and Mg++ content of cells showed a moderate negative correlation (r = -0.58 and -0.65) with mitochondrial swelling in the material of all experiments and Ca++ content a moderate positive one (r = 0.58), but the Na+ content and intracellular water showed no correlation. The percentages of flocculent densities in mitochondria showed a moderate positive correlation (r = 0.43) with the Ca++ content of the cells and a moderate negative correlation (r = -0.61) with the magnesium content of the cells.

4-Chloromercuribenzenesulfonate↗
PubMed1975

The application of electron microscopy and cellular biochemistry to the autopsy. Observations on cellular changes in human shock.

A method based on the utilization of electron microscopy, morphometric analysis, tissue culture, and biochemical analysis in the study of human autopsies is described. In this method rapid sampling immediately following somatic death is conducted in order to make meaningful the application of such techniques. In addition to describing the procedure, we present some new findings relating to cellular changes associated with shock. As in cellular pathobiology, it is of utmost importance that ultrastructural changes be correlated with alterations in chemistry and function.

Adolescent↗
PubMed1975

Effects of fixation and postfixation treatments on volume of injured cells;.

The effects of fixation with glutaraldehyde (GA), formaldehyde (FA), glutaraldehyde-formaldehyde (GA-FA), flutaraldehyde-osmium tetroxide (GA-Os04) and osmium tetroxide (OsO4) on cel volume were studied in control, p-chloromercuribenzene sulfonic acid (PCMBS)-treated and hypotonically-treated Ehrlich ascites tumor cells. Among the variables investigated were concentration of the tixative agent, osmolity of the buffer, total osmolaity of the fixation solution, osmolaltity of the postfixation buffer and the time of fixation and postfixation treatment; in addition, the effects of adding calcium and high molecular weight compounds to the fixative solution were studied. When the effects of standard fixatives on control, PCMBS- and hypotonically-treated cells were compared, marked differences were apparent in the behavior of control and injured cells. Control cells retained near prefixation volume in 3% GA and 3% GA-1% OsO4, swelled in 4% FA or 1% OsO4 and phosphate buffer (tkrp), whereas tpcmbs (310 mosM KRP)- and hypotonically-treated cells (103 mos M KRP) shrank in all aldehyde fixatives but swelled in 1% OsO4. Reducing the buffer osmolality had similar effects on control and injured cells although, there were variations in degree...

Animals↗
PubMed1975

Studies on the pathogenesis of cell injury: effects of inhibitors of metabolism and membrane function on the mitochondria of Ehrlich ascites tumor cells.

The effects of cell injury on Ehrlich ascites tumor cell mitochondria were studied using two model injuries: (1) interference with cell membrane function and (2) inhibition of ATP synthesis with specific mitochondrial inhibitors. These studies indicate a good correlation between level of ATP and number of swollen mitochondria and between swollen mitochondria and occurrence of flocculent densities. No correlation existed between total ADP level and percentage of condensed mitochondria if all ADP values were considered, although a biphasic relationship appeared to exist between the number of condensed mitochondria and the levels of ATP. The study suggests a reproducible sequence of mitochondrial events following either inhibition of ATP synthesis or induction of cell membrane permeability with the nonpenetrating, membrane-damaging agent p-chloromercuribenzene sulfonic acid. These include the rapid appearance of condensed mitochondria, the reinflation of these to resemble orthodox mitochondria, and the occurrence of high amplitude swelling followed by flocculent densities or calcification, or both. Calcification did not occur when ATP synthesis was inhibited but did occur when the cell membrane was damaged with p-chloromercuribenzene sulfonic acid. It is suggested that the early mitochondrial condensation is related to loss of ions and water from the mitochondrial inner compartment following inhibition of active accumulation systems. It is furthermore suggested that the appearance of the condensed mitochondrial state can be taken as evidence of the intactness of the mitochondrial respiratory chain. The occurrence of swelling indicates structural changes in the mitochondrial inner membrane which occur following loss of ability for ATP synthesis.

Adenosine Diphosphate↗
PubMed1975

Iron metabolism and cell membranes. III. Iron-induced alterations in HeLa cells.

The morphologic characteristics of acute iron loading were studied in HeLa cells incubated in an iron-enriched Eagle's medium containing 500 mug/ml of iron. Chemical studies showed that ferritin synthesis was rapidly induced and the concentration of intracellular ferritin increased up to 72 hours. Closely coupled with an increase in HeLa cell ferritin was a marked decrease in the rate of cell multiplication. The significant ultrastructural findings of iron-induced HeLa cell injury are characterized by the appearance of both autophagic multivesicular and residual bodies over the first 72 hours of iron incubation. The prominence of multivesicular bodies was noted after only 4 hours' incubation, with iron and myelin figures first appearing after 6 hours. Thus, the partial arrest of cell multiplication was associated with an increase in cytoplasmic residual bodies containing iron and other debris. The distribution of intracellular ferritin within HeLa cells differs significantly from the distribution described previously in hepatic parenchymal cells. In HeLa cells, ferritin particles were confined to lysosomal vesicles and were not identified in cell sap, endoplasmic reticulum, or Golgi apparatus.

Acid Phosphatase↗
PubMed1975

Lysosomal degradation of cell organelles. I. Ultrastructural analysis of uptake and digestion of intravenously injected mitochondria by Kupffer cells.

An experimental model comparable to autophagocytosis is presented to evaluate lysosomal degradation of biologic membranes in vivo. This design takes advantage of the efficient phagocytic capacity of Kupffer cells. For this purpose, mitochondria were isolated from one rat liver (inbred strain) and subsequently injected intravenously into a series of rats, which were sacrificed at various time points. The uptake and intralysosomal digestion were examined by electron microscopy. Mitochondria were seen in the sinusoids and attached to the surface of Kupffer cells 1 to 3 minutes after injection. One or two mitochondrial profiles were trapped in cavelike structures often embraced by long hyaloplasmic pseudopods. By 5 and 10 minutes, the mitochondria were in single membrane-bound phagosomes within the Kupffer cells and early signs of mitochondrial alterations were present, e.g., loss of cristae and condensation. At 30 minutes and 1 hour the mitochondria were seen in large vacuoles which contained up to 20 profiles in a single section. The mitochondria showed evident signs of digestion such as membrane fragmentation and flocculent densities. By 4 hours and especially by 8 hours, most digestive vacuoles were laden with flocculent membrane debris. By 24 hours, the Kupffer cells showed multiple lysosomal structures which were irregular in shape and small. These often contained a number of lipid-like droplets of various electron densities and pentalaminar structures. By 2 and 5 days, the Kupffer cells had returned to their normal appearance although the lysosomal apparatus was still prominent. No uptake of mitochondria was seen in endothelial cells, fat-storing cells, or hepatocytes. It is concluded that lysosomes have an efficient capacity to digest mitochondria. Some lipid remnants are not completely or slowly degraded by Kupffer cell lysosomes but remain in "residual bodies" for up to 1 or 2 days.

Animals↗
PubMed1975

Lysosomal degradation of cell organelles. II. Ultrastructural analysis of uptake and digestion of intravenously injected microsomes and ribosomes by Kupffer cells.

Rough and smooth microsomes, "mixed" or total microsomes, and ribosomes were isolated from one single rat liver and subsequently injected intravenously into a series of inbred rats. The uptake and the degradation of the injected organelles by Kupffer cells were followed by means of electron microscopic analysis. By 1 minute after injection, microsomes were seen attached to the surface of Kupffer cells separated by a gap of 200 to 300 A. No attachment to hepatocytes, fat-storing cells, or endothelial cells was seen. By 5 and 10 minutes, most microsomes were phagocytosed and sequestered in large numbers within single membrane-enclosed vacuoles or phagosomes. The engulfment proceeded by two mechanisms: (1) most frequently, flaplike processes of cytoplasm embraced aggregates of microsomes, concomitant with the formation of indention of the cytoplasm; (2) occasionally, single microsomal profiles were taken up by bristle-coated endocytic vacuoles. Ribosomes were also seen penetrating into the wormlike structures (micropinocytosis vermiformis) at the cell surface. At 30 minutes after injection, clear signs of alteration were noted starting with vesicle aggregation, clumping, and elongation of the microsomal profiles. The ribosomes were quickly stripped from their microsomal membranes and marginated to the inside of the vacuoles but separated from the limiting membrane by a distance of 200 to 300 A. By 1 and 2 hours, disruption of the vesicles into membrane fragments and formation of dense material in and between the profiles occurred. By 8 hours it was difficult to recognize the degradation products as membrane derivatives. The digestive vacuoles retained their size at this time interval. Typical pentalaminar structures were observed. By 14 to 24 hours the digestive vacuoles became electron lucent and appeared to shrink, and in addition to containing various types of granular material, many were laden with lipid-like droplets presumed to be conglomerates of phospholipid remnants. Rough microsomes, when compared to smooth microsomes, gave rise to more granular material within the digestive vacuoles. Ribosomes were still identifiable 24 hours after injection, indicative of a somewhat slower rate of degradation. Accumulation of various types of lipid-like droplets in the "residual bodies" was typical after microsomal injections. It is concluded that although microsomes appear to be phagocytosed at a quicker rate than mitochondria, they are digested within the lysosomal apparatus of the Kupffer cells at a somewhat slower rate. This especially seems to be the case for ribosomes. Heterophagy of microsomes is one source of residual bodies.

Animals↗
PubMed1975

Lysosomal degradation of cell organelles. III. Uptake and disappearance in Kupffer cells of intravenously injected isotope-labeled mitochondria and microsomes in vivo and in vitro.

14C-leucine and 3H-glycerol-labeled microsomes and mitochondria were intravenously injected into a series of highly inbred rats. The uptake and disappearance of the organelles were followed in a crude liver lysosomal fraction and in serum. Approximately half of the injected dose was recovered in the liver, and only smaller amounts were found in lungs, kidneys, spleen, and heart. The clearance in serum was more rapid for microsomes (t1/2, 5 to 15 minutes) than for mitochondria (t1/2 30 to 60 minutes). Both organelles showed a biphasic type of disappearance curve consistent with the two-phase theory of phagocytosis: attachment and engulfment. The estimated half-life for mitochondria of the liver was in the range of 3 to 4 hours, whereas that of the microsomes was considerably longer, or 8 hours. There was an increase of trichloroacetic acid-soluble material in the crude lysosomal fraction up to 2 hours after injection of glycerol-labeled microsomes, whereas the peak was reached at 60 minutes after 14C-leucine labeling. In vitro hydrolysis rate of hydrolysis. Experiments with Kupffer cells previously labeled with Thorotrast and biochemical assay of hydrolysis indicated that there was a lag phase of approximately 10 to 20 minutes before the phagosomes gained acid hydrolases, presumably by fusion with lysosomes. It is concluded at somewhat different rates. The remnants from lipid degradation, in comparison with protein degradation, seem to remain for a longer period within the lysosomal apparatus. These results are compatible with the concept that lysosomes represent an important, and at the present the only well defined locus for organelle turnover.

Animals↗
PubMed1975

Effects of shock on the pancreatic acinar cell. Cellular and subcellular effects in humans.

Pancreatic tissues from 22 patients with a wide variety of types of shock were obtained within minutes of somatic death for light and electron microscopy and for cytochemical studies. By light microscopy, it was difficult to ascertain any differences between the shock groups; however, electron microscopy disclosed subcellular alterations that could be correlated well with the type, severity, and duration of shock. Mild cases of shock or shock of short duration showed mild cell damage, while extreme cases of hemorrhagic or septic shock showed cell death and necrosis. No morphological evidence for lysosomal initiation of damage was seen, but it is clear that the pancreas can undergo severe cell injury during shock that could result in release of further damaging enzymes, most probably from zymogen granules rather than from lysosomes.

Adolescent↗
PubMed1975

Studies on the modification of the cellular response to injury. III. Electron microscopic studies on the protective effect of acidosis on p-chloromercuribenzene sulfonic acid-(PCMBS) induced injury of Ehrlich ascites tumor cells.

Extracellular acidosis (pH 6.5) was found to significantly retard the response of Ehrlich ascites tumor cells (EATC) to direct plasma membrane injury with the non-penetrating organic mercurial compound, p-chloromercuribenzene sulfonic acid (PCMBS). Treatment of cells with 1 mM PCMBS resulted in loss of viability of all cells by 45 minutes at pH 7.4, and by 90 minutes at pH 6.5. Pregression of cellular changes through the various stages of cell injury at the ultrastructural level was correspondingly slower at pH 6.5. The results support the concept that stage 3 of cell injury, associated with condensed mitochondria, dilated ER and swollen cell sap is compatible with cell survival, while stage 5 with high amplitude swelling of mitochondria, fragmentation of membrane systems, and beginning of karyolysis is characteristic of irreversible injury. All cells entered stage 3 at 7.5 minutes at pH 7.4, while essentially all cells entered stage 5 by 45 minutes. At pH 6.5, stage 3 was maintained for 45 minutes and 100% of the cells entered stage 5 by 90 minutes. Although the mechanism of the protection against PCMBS-induced injury is not known, the present electron microscopical results are compatible with the hypothesis that the extracellular acidosis acts to partially stabilize plasma membrane, perhaps by interaction with sulfhydryl (SH) groups.

Acidosis↗
PubMed1975

Studies on modification on the cellular response to injury.

Extracellular acidosis (pH 6.6) has been found to delay the lethal effect of p-chloromercuribenzene sulfonic acid on Ehrlich ascites tumor cells. At pH 6.6, 50 per cent of the cells died within approximately 80 minutes, compared with approximately 10 minutes at pH 7.5 or approximately 5 minutes at pH 8.0. It was also observed that low pH produced a dissociation between potassium loss, ATP levels, cell volume, and cell death. The possible mechanism of this effect is discussed; it is our hypothesis that it involves proton interactions with plasma membrane components which either affect available membrane sulfhydryl groups or otherwise stabilize the cell membrane against loss of semipermeable characteristics and cellular lysis.

4-Chloromercuribenzenesulfonate↗
PubMed1975

Studies of cellular recovery from injury. I. Recovery from anoxia in Ehrlich ascites tumor cells.

The reversibility of changes in ultrastructure, K+, and ATP content was studied in experimental injury of Ehrlich ascites tumor cells. Different grades of injury resulted from incubations in N2 atmosphere and omitting substrate after which air and glucose were reinstated. The changes observed in cells after 1 hour of anoxia such as dilations of endoplasmic reticulum, complex invaginations of plasma membrane, and slight condensation of mitochondria, as well as a drop of K+ and ATP content to a level approximating 40 per cent of the paired controls, were entirely reversible. After 2 hours of anoxia approximately 50 per cent of the cells recovered, but after 3 and 4 hour of anoxia most of the cells were irreversibly damaged showing markedly swollen mitochondria with flocculent densities.

Adenosine Triphosphate↗
PubMed1974

Extracellular acidosis protects Ehrlich ascites tumor cells and rat renal cortex against anoxic injury.

The present study indicates that extracellular acidosis protects Ehrlich ascites tumor cells and rat kidney cortex cells against injury from anoxia. Parameters measured included cell potassium, adenosine 5'-triphosphate, and uptake of vital dyes. Cells survived longer at a pH of 5.6 to 6.5 than at a pH of 7.4; pH 7.9 was most detrimental. These findings indicate that production of protons by anoxic cells may be a protective feedback mechanism.

Anaerobiosis↗