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Biomedical subjects

B F Trump

Publications and source records attributed to B F Trump.

At least 163 records · Page 9Linked to original sources

A simple method of staining juxtaglomerular granules in the rat kidney for high resolution light microscopy.

A simple method for the demonstration of juxtaglomerular granules in Epon embedded semithin (0.5-1 micrometer) sections has been developed as follows: sections are prepared as for routine electron microscopy except that before dehydration, the tissues are immersed in 0.5% uranyl acetate in Veronal acetate buffer (pH 5.0) overnight at room temperature. After sectioning on an ultramicrotome, the semithin sections are briefly stained with toluidine blue-pyronin Y. After staining, the section is rinsed in running tap water and then air dried. Under a light microscope with a 40 X or a 100 X objective, the juxtaglomerular granules appear as deep purple particles and are thus easily separated from the bluish cytoplasm of the juxtaglomerular cells. Cellular organelles in other cells of the kidney were also clearly stained and their fine structure distinguishable.

Animals↗

Studies on carcinogenesis of human prostate. II. Long-term explant culture of normal prostate and benign prostatic hyperplasia: light microscopy.

Light microscopic and histochemical changes in normal human prostate and benign prostatic hyperplasia (BPH) during long-term explant culture were characterized. Normal human prostate obtained at immediate autopsy of young adults or BPH obtained at the time of surgery were maintained in explant culture as long as 24 weeks. Morphologic alterations in glandular epithelium and stroma in response to culture conditions were assessed by light microscopy and histochemistry of mucosubstances. The histologic and histochemical responses of normal prostate and BPH to in vitro conditions were essentially identical. Within 1 week, secretory epithelial cells became necrotic and sloughed into acinar lumina. Remaining epithelial cells proliferated, repopulated acinar structures, and migrated onto explant surfaces forming a new well-differentiated epithelium characterized by synthesis and secretion of neutral and acidic mucosubstances. During subsequent periods in vitro, synthesis and secretion of mucosubstances gradually diminished whereas the stroma and deep glandular structures became necrotic. Our observations suggest that cells comprising the new epithelium in cultured explants of normal human prostate and BPH are derived from prostatic basal cells.

Adolescent↗

Studies on carcinogenesis of human prostate. III. Long-term explant culture of normal prostate and benign prostatic hyperplasia: transmission and scanning electron microscopy.

Ultrastructural changes in normal human prostate and benign prostatic hyperplasia (BPH) during long-term explant culture were compared. Explants of normal prostate obtained at immediate autopsy of young adults of BPH obtained at the time of surgery were maintained as long as 24 weeks in vitro. Ultrastructural changes occurring in epithelial cells during culture were monitored by transmission and scanning electron microscopy. Essentially identical results were found for normal prostate and BPH. During the first week of culture, secretory epithelial cells degenerated and sloughed into the acinar lumen, resulting in an accumulation of necrotic debris. During this period, however, epithelial cells with ultrastructural characteristics of basal cells remained viable, repopulated glandular structures, migrated from glands and ducts, and epithelialized adjacent cut surfaces, eventually covering the explant. On explant surfaces, these basal cells initially were squamous-like, but they later became typically cuboidal, polygonal, or sometimes columnar and formed an epithelium, two cells or more thick. Epithelium with similar features lined acini within explants. Epithelial cells at the surface or within explants were distinguished by the presence of microvilli, junctional complexes, multiple Golgi complexes, well-developed rough endoplasmic reticulum, polyribosomes, nuclei with prominent nucleoli, orthodox mitochondria, scattered tonofilaments, and a basal lamina. Some epithelial cells extended from the lumen to the basal lamina; others were oriented along the basal lamina and did not extend to the lumen. By 1--2 weeks in vitro, these epithelial cells began synthesis of mucus-like material. At later intervals of culture, microvilli were shortened and mucosubstances were reduced. During culture, the stroma became progressively hypocellular and necrotic. In summary, explant-cultured epithelial cells of normal human prostate or BPH were similar ultrastructurally and were found to originate from basal cells, which alone survive culture conditions.

Adolescent↗

Comparison of benzo(a)pyrene metabolism in bronchus, esophagus, colon, and duodenum from the same individual.

The metabolism of benzo(a)pyrene has been investigated in cultured normal human bronchus, colon, duodenum, and esophagus obtained from the same patient. The highest total metabolism was found in bronchus and duodenum, while the highest mean binding level was observed in the bronchus followed, in order, by the esophagus, duodenum, and transverse colon. A 30-fold interindividual variation in the binding level was found in each of the four organs studied, and a positive correlation between the binding levels in bronchus, colon, and duodenum was found. In human bronchus, a positive correlation was found between level of binding of benzo(a)pyrene to DNA and the amount of both benzo(a)pyrene 7,8-diol and the combined group of 3-hydroxybenzo(a)pyrene, benzo(a)pyrene 9,10-diol, and water-soluble metabolites. A significantly higher relative amount of benzo(a)pyrene tetrols and benzo(a)pyrene 9,10-diol was formed by human bronchus compared to the gastrointestinal tissues, while a higher level of benzo(a)pyrene phenols was formed by the latter. The relative distribution of benzo(a)pyrene-DNA adducts was similar in all four organs, the major DNA adduct being formed by trans-addition of anti-7,8-dihydroxy-9,10-epoxide-7,8,9,10-tetrahydrobenzo(a)pyrene to the 2-amino group at guanine. These results indicate that the metabolism of benzo(a)pyrene by at least four different organs is qualitatively similar but that quantitative differences exist.

Adolescent↗

The pathophysiology of septic shock: acute renal failure in rats following live E coli injection. A histochemical study of the proximal tubules.

Acute renal failure was induced in rats by injection of a lethal dose of live Escherichia coli. Enzyme activities of the proximal tubule were studied histochemically at three, six, and 12 hours following E coli injection. The enzymes examined were alkaline phosphatase (A1Pase), acid phosphatase (AcPase), adenosine triphosphatase (ATPase), succinate dehydrogenase (SDH), glucose-6-phosphatase (G6Pase), and glucose-6-phosphate dehydrogenase (G6PDH). At three hours, ATPase activity was slightly decreased, while other enzymes showed no changes in activities at this time. At six hours, a slight increase in AcPase activity was seen in the pars recta. At this time, although A1Pase showed no change in activity, other enzymes revealed slight decreases in activities: G6Pase and SDH in the pars convoluta, ATPase in the pars convoluta and pars recta, and G6PDH in pars recta. At 12 hours after treatment, all enzymes showed decreases in activities; however, no necrotic tubule changes were detectable by light microscopy. Since sodium reabsorption in proximal tubules requires a sodium pump consisting of Na-K ATPase, early histochemical changes in ATPase activity in proximal tubule following bacteremia may be related to early changes in sodium reabsorption causing polyuria and to the subsequent development of acute renal failure.

Acute Kidney Injury↗

The pathophysiology of septic shock: studies of reticuloendothelial system function and liver high-energy metabolism in rats following sublethal and lethal Escherichia coli injection.

Phagocytic indices and the hepatic energy charge (ATP + 1/2 ADP/ATP + ADP + AMP) were studied in rats after intravenous sublethal or lethal injection of live Escherichia coli (12--15 X 10(8) or 4--5 X 10(8) organisms/100 gm of body weight). Phagocytic indices as determined by carbon clearance test were progressively decreased in both groups from 0.063 of control to 0.028 or 0.022 (sublethal or lethal) at 12 hours (P less than 0.001). This was mainly due to marked decrease in carbon uptake in the liver even though a marked accumulation of carbon occurred in the lung. At 24 hours in the sublethal group, the phagocytic index was elevated (P less than 0.01). With regard to the spleen, carbon uptake in the sublethal group remained unchanged, in contrast to the decreased uptake in the lethal group, leading to a significant difference between sublethal and lethal groups (P less than 0.05 or less at six and 12 hours). On the other hand, the hepatic energy charge levels in the lethal group progressively decreased from 0.86 to 0.62 until death (P less than 0.001), while those in the sublethal group remained moderately decreased. Following carbon administration, the hepatic energy charges in the control and lethal groups were decreased, while those in the sublethal group remained unchanged. These results suggest a functional reserve of phagocytic activity in liver and spleen and activated high-energy metabolism in the liver for phagocytosis may play a role in determining survival from bacteremic shock.

Adenosine Triphosphate↗

The pathophysiology of septic shock: changes in hemodynamics in rats following live E coli injection. An application of the thermodilution method for measurement of cardiac output.

Fifteen anesthetized rats, 273 +/- 9 gm (SEM), were monitored hemodynamically for six hours following an IV injection of a sublethal (4--5) X 10(8) organisms/100 gm body wt, n = 5) or lethal 12--15 X 10(8) organisms/100 gm body wt, n = 5) dose of live Escherichia coli or saline (control, n = 5). A transpulmonary thermodilution method was used for measurement of cardiac output. Changes in the arterial blood temperature and pressure were recorded on a polygraph. In a simulated hydraulic model system, the measured flow rate was well correlated ( r = 0.993, P less than 0.001) with various actual flow readings (30--130 ml/minute). A sublethal dose resulted in a transient hyperdynamic state in the early stage; the cardiac index was increased from the initial rate of 258.2 +/- 9.4 to 312.3 +/- 10.7 ml/minute/kg with a concomitant decrease in the total peripheral resistance from 0.497 +/- 0.019 to 0.367 +/- 0.022 mm Hg/ml/minute/kg which was sustained for 120 minutes after treatment. In contrast, a lethal dose caused a prolonged hyperdynamic state in the early stage followed by a hypodynamic state in the late stage. The cardiac index was increased from 2.54 +/- 4.5 to 306.0 +/- 10.8 ml/minute/kg and the total peripheral resistance was decreased from 0.513 +/- 0.024 to 0.337 +/- 0.015 mm Hg/ml/minute/kg in the early stage, while, in the late stage, the former decreased to 195.0 +/- 13.3 ml/minute/Kg and the latter increased to 0.615 +/0 0.054 m Hg/ml/minute/kg. The mean arterial blood pressure was decreased in both groups in the early stage but maintained above 100 mm Hg. Essentially, no hemodynamic changes were noted in the control group. These results confirm our hypothesis that an injection of live E coli can produce a hyperdynamic state in the early stage as well as hypodynamic state in the late stage, and that serial hemodynamic studies on bacteremia in rats can be done successfully using the thermodilution method.

Animals↗

A study of oxidative phosphorylative activity and calcium-induced respiration of rat liver mitochondria following living Escherichia coli injection.

Mechanisms of subcellular dysfunction of the liver in sepsis are still obscure. The present study investigates changes in oxidative phosphorylative activity and calcium-induced respiration of rat liver mitochondria following live Escherichia coli injection (E coli, Serotype: 0--18. A 1.25--1.5 X 10(9)/100 gm body wt inoculum of E coli bacteria was injected via the tail vein, causing a 100% mortality rate within 24 hours after injection. In order to determine alteration of liver mitochondrial membrane permeability, serum ornithine carbamoyltransferase activity was measured following E coli injection. This activity increased ten to 100-fold over that of controls with time following injection. However, the yield of liver mitochondria from treated rats, estimated by the amount of collected mitochondrial protein and the recovery rate of succinate dehydrogenase activity in the final mitochondrial suspensions, was not significantly different from that of controls. Mitochondrial oxidative phosphorylative activity measured using glutamate as a substrate was enhanced throughout all period to death (P less than 0.01 at three and six hours, P less than 0.05 in the fatal stage) and was associated with concomitant increases in respiratory control ratios. Similar results were obtained using beta-hydroxybutyrate as a substrate. This enhancement was accompanied by an increase in 2-4-dinitrophenol-stimulated ATPase activity (160% at three hours and 130% in the fatal stage). Calcium-induced stimulation of mitochondrial respiration as well as initial calcium uptake rate linked to respiration, using glutamate as a substrate, were higher in liver mitochondria from rats with E coli treatment than in those of controls throughout all periods (P less than 0.01 or less). These results suggest the coexistence of hyperfunctioning as well as deteriorated mitochondria following lethal treatment with E coli.

3-Hydroxybutyric Acid↗

N-Methyl-N-nitrosourea and saccharin: effects on epithelium of normal human urinary bladder in vitro.

The effects of N-methyl-N-nitrosourea (MNU) and saccharin on the histology of normal human bladder "urothelium" (i.e., the epithelium of the urinary bladder) were studied in long-term explant cultures. In MNU-treated cultures, a dose response was observed. Single doses of 1-100 micrograms MNU/ml induced atypical focal hyperplasia, which reverted to a single or a double cell layer as seen in controls. Exophytic, papillary-like hyperplastic structures were noted after a single dose of 10 or 100 micrograms MNU/ml. In contrast to single doses, multiple doses (given every 2 wk) of MNU at 5 or 10 micrograms/ml resulted in striking focal proliferation of dysplastic spindle cells in as little as 6 weeks (three doses of MNU). At 0.5% saccharin, urothelium on explant surfaces resembled that of controls, except in one instance in which mild focal hyperplasia persisted. In the presence of saccharin, hyperplasia induced by a single dose of MNU persisted. Following three multiple doses of MNU in the presence of saccharin, spindle cell hyperplasia was induced similar to that seen with multiple doses of MNU alone, although nuclei appeared more pleomorphic and hyperchromatic in the presence of saccharin.

Cocarcinogenesis↗

Studies of host factors in carcinogenesis using cultured human tissues and cells.

Recent progress in the development of conditions for culturing epithelial tissues and cells from adult humans has provided cancer researchers with an opportunity to investigate directly the various facets of carcinogenesis in human cells. Studies of activation and deactivation of several classes of chemical carcinogens have revealed that the metabolic pathways and the predominant adducts formed with DNA are generally similar in humans and experimental animals. Wide quantitative interindividual differences are found in humans and other outbred animal species. When the metabolic capabilities of specimens from different levels of biological organization are compared, the profile of benzo[a]pyrene metabolites is similar in cultured tissues and cells, but subcellular fractions, e.g., microsomes, produce a qualitatively and quantitatively aberrant pattern. To test the interactive effects of cell types in the metabolic activation of carcinogens and to assess further interindividual differences among people, human tissue- and cell-mediated mutagenesis assays have been developed. The fact that terminally differentiated cells such as pulmonary alveolar macrophages can activate benzo[a]pyrene and mediate an increase in frequencies of mutations and sister chromatid exchanges in cocultivated 'detector' cell populations, i.e., Chinese hamster V79 cells, suggests that non-target cells of chemical carcinogens may play an important role in the activation of environmental carcinogens. Malignant transformation of human epithelial and fibroblastic cells in vitro has been accomplished by several research groups. Asbestos, a cocarcinogenic agent in bronchogenic carcinogenesis, has been found to induce polyploid epithelial lesions with atypical cells in human bronchial explants. Carcinogenesis studies using cultured human tissues and cells are providing new insights into the mechanisms of carcinogenesis and are useful in identifying host factors that influence individual risk to environmental carcinogens.

Biotransformation↗

Aryl hydrocarbon hydroxylase in human prostate.

Aryl hydrocarbon hydroxylase (AHH) was present in explant cultures of human prostate obtained from surgery of benign prostatic hyperplasia and was inducible by benz[a]anthracene (BA). The induction of AHH ranged from 14- to 150-fold when compared with control values and 10-fold variation of AHH inducibility among individuals was observed. Epithelial cells grown from human prostate tissue also contained measurable AHH activity and AHH was inducible by BA and 7,12-dimethylbenz[a]anthracene (DMBA). Inducibility of AHH by BA ranged from 2- to 63-fold. The inducibility of AHH by DMBA was always less than that by BA. In cells treated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), there were no changes in AHH activity. These findings support the view that the human prostate is susceptible to environmental polycyclic hydrocarbon carcinogens and that environmental and occupational factors might contribute to the etiology of human prostatic carcinoma.

9,10-Dimethyl-1,2-benzanthracene↗

Mouse liver cell culture. I. Hepatocyte isolation.

A method for isolation of mouse liver cells by a two-step perfusion with calcium and magnesium-free Hanks' salt solution followed by a medium containing collagenase is described. Several variations of the commonly used procedure for rat liver cell isolation were quantitatively compared with respect to cell yield and viability. The optimal isolation technique involved perfusion through the hepatic portal vein and routinely produced an average of 2.3 x 10(6) viable liver cells/g body weight. Optimal perfusate collagenase concentration was found to be 100 U of enzyme activity per milliliter of perfusate. Light and electron microscopic evaluation of liver morphology after several steps of the isolation showed distinct morphologic changes in hepatocytes and other liver cells during perfusion. After perfusion with Hanks' calcium- and magnesium-free solution, many hepatocytes exhibited early reversible cell injury. These changes included vesiculation and slight swelling of the endoplasmic reticulum as well as mitochondrial matrix condensation. Subsequent to perfusion with collagenase, the majority of hepatocytes appeared connected to one another only by tight junctional complexes at the bile canaliculi. Multiple evaginations were seen on the outer membrane resembling microville and probably represented the remains of cell-to-cell interdigitations between hepatocytes and sinusoidal lining cells from the space of Disse. The cytoplasmic injury seen after Hanks' perfusion was reversed after collagenase perfusion. After mechanical dispersion, isolated mouse hepatocytes were spherical in shape and existed as individual cells; many (80 to 85%) were binucleated under hase contrast light microscopy. By electron microscopy, cells appeared morphologically similar in cytoplasmic constitution to that seen in intact nonaltered liver cells.

Animals↗

Mouse liver cell culture. II. Primary culture.

Mouse hepatocytes in primary culture were characterized. Hepatocytes were isolated by the two-step hepatic portal vein perfusion method described previously. An optimal cell attachment of 43% was noted after 2 h incubation in 10% fetal bovine serum. Minimal attachment (less than 7%) occurred in serumless medium. Serum concentrations above 10% and attachment durations greater that 2 h resulted in no increased attachment of viable cells. Nonviable cells, however, progressively attached when both of these parameters were increased. Survival data of the cells in culture resembled those reported for rat hepatocytes in primary culture. A progressive decrease in survival was noted following initial attachment until only approximately 15% of initially plated cells remained viable and attached after 8 d culture. The decrease in survival was accompanied by morphologic changes including flattening and elongation of the cells, some multinucleation, and disruption of monolayer groups.

Animals↗

Cultured human bronchial epithelial cells: blood group antigens, keratin, collagens, and fibronectin.

Immunofluorescence and immunoperoxidase methods were used to identify constituents and products of cultured human bronchial epithelial cells and fibroblasts. Epithelial cells, but not fibroblasts, from patients with blood Types A or B reacted to the respective antisera to either the A or B blood group antigens. However, neither the epithelial cells nor the fibroblasts from patients with blood type O[H] reacted with the anti-H antisera. Epithelial cells in primary culture reacted with antibody to prekeratin proteins from human stratum corneum and fibroblasts did not react. Moreover, keratin filaments were assembled in vitro from proteins isolated from the epithelial cells. These immunological and biochemical data support previous morphological observations that human bronchial epithelial cells in primary culture shift progressively from a mucociliary epithelium to a keratinizing epithelium. Epithelial cells and fibroblasts could also be identified by their reactivity to anti-collagen antibodies. Fibroblasts reacted strongly with antibodies to Types I and III collagens and epithelial cells did not. On the other hand, epithelial cells reacted weakly with antibodies to Type IV collagen and fibroblasts were completely negative. Both epithelial cells and fibroblasts reacted with antibody to fibronectin; however, the distribution of fibronectin differed in the two cell types. In epithelial cells, fibronectin was restricted to the cell surface, whereas in fibroblasts it was found on the cell surface and in the extracellular matrix where fibrils of fibronectin were both cell associated and deposited on the surface of the dish where the fibroblasts had migrated.

ABO Blood-Group System↗

Studies on the pathogenesis of ischemic cell injury. VI. Mitochondrial flocculent densities in autolysis.

Flocculent densities in the matrix of mitochondria have become quite important in cell pathology since, when prominent, they indicate irreversible cell injury. The morphology and chemical nature of these flocculent densities have been studied in Kidney after various periods of autolysis in vitro in whole tissue samples and in isolated mitochondria. After 30 to 60 min of ischemia, flocculent densities were seen only occasionally and they were most prominent in samples subjected to mechanical damage during isolation. However, in 2- and 4-h samples numerous densities were seen. The size of the densities increased with time, being about 1,400 A in diameter at 4 h. Densities were also seen in mitochondria isolated in medium containing EDTA. They were seen only in the mitochondrial matrix, and could occasionally be found in condensed mitochondria. Small densities were generally round but larger one varied in shape and often appeared as aggregates of smaller densities. Digestion of the densities from water-soluble glycol methacrylate embedded samples was successful with pronase, but neither acid nor lipid solvents were effective. calcium or inorganic phosphate content of isolated mitochondria did not show an increase parallel to the occurrence of flocculent densities. The results suggest that the densities consist predominantly of protein and are probably formed through denaturation of proteins of the mitochondrial matrix and/or the inner membrane.

Animals↗