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Biomedical subjects

B F Trump

Publications and source records attributed to B F Trump.

At least 253 records · Page 14Linked to original sources
PubMed1978

Explant culture of rat colon: a model system for studying metabolism of chemical carcinogens.

An explant culture system has been developed for the long-term maintenance of colonic tissue from the rat. Explants of 1 cm2 in size were placed in tissue-culture dishes to which was added 2 ml of CMRL-1066 medium supplemented with glucose, hydrocortisone, beta-retinyl acetate, and either 2.5% bovine albumin or 5% fetal bovine serum. The dishes were placed in a controlled-atmosphere chamber which was gassed with 95% O2 and 5% CO2. The chamber then was placed on a rocker platform which rocked at 10 cycles per min causing the medium to flow intermittently over the epithelial surface. The explants were incubated at 30 degrees C. The viability of the tissue was measured both by incorporation of specific precursors into cellular macromolecules and by monitoring of tissue morphology with light and electron microscopy. Cultured rat colon was able to metabolize benzo[alpha]pyrene, 7,12-dimethylbenz[alpha]anthracene, aflatoxin B1, dimethylnitrosamine, 1,2-dimethylhydrazine, and methylazoxymethanol acetate into chemical species that bind to cellular DNA and protein.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1978

Isolation and characterization of epithelial cells from bovine pancreatic duct.

Epithelial cells derived from bovine pancreatic duct have been grown continuously in culture for 30 weeks (approximately 90 doublings of the cell population). The cells were grown in Eagle's minimal essential medium supplemented with 10% heat-inactivated fetal bovine serum, 2 mM glutamine, 0.1 mM nonessential amino acids, and antibiotics. In confluent cultures, the cells are multilayered and form circular structures. When tested at various passages, the cells neither formed colonies in soft agar nor produced tumors after inoculation into athymic, nude mice. Hydrocortisone (1 and 5 microgram per ml) and insulin (1,5 and 10 microgram per ml) had no effect on the growth of the cells. beta-Retinyl acetate inhibited growth rate and cell yield at a concentration of 5 microgram per ml but was not growth-inhibitory at lower concentrations. By electron microscopy the cells have numerous mitochondria, Golgi and microvilli. Mucous droplets were observed in a small proportion of the cells. Desmosome-like structures and occluding junctions were observed more frequently between cells that had been transferred as aggregates than between cells transferred as single cells. Cytochemical studies indicated that some cells produce PAS positive granules that were not removed after treatment of the cultures with diastase. Eleven cell clones were isolated from the mass culture. The growth rates of the clones are different as well as the period of time in which the clones can be propagated in vitro.

Animals↗
PubMed1978

Long-term organ culture of adult rat colon.

Colon explants from adult rats were maintained in culture for over 3 months in our laboratories with good epithelial preservation and cellular differentiation. The light and transmission electron microscopic features of rat colon mucosa during the culture period are described. In all the explants that remained viable, there was an initial phase of degeneration of the surface and crypt cells, later these areas were repopulated in one week, showing well-formed crypts, goblet cells, and ultrastructural features such as extensive lateral interdigitations, microvilli and glycocalyx--typical of colon. The effect of in vivo carcinogen pretreatment was also studied. The explant culture from control untreated animals showed good epithelial differentiation with crypts until 6 weeks. In contrast, the explants from animals pretreated with 4 weekly doses of azoxymethane consistently showed epithelial differentiation with well-formed crypts up to 13 weeks.

Animals↗
PubMed1978

Human bronchus-mediated mutagenesis of mammalian cells by carcinogenic polynuclear aromatic hydrocarbons.

Cultured human bronchial explants activated benzo[alpha]pyrene (BzaP) into electrophilic metabolites that bind to DNA in bronchial epithelial cells. Promutagenic and mutagenic metabolites of BzaP were also released into the culture medium. An increase in mutation frequency for ouabain resistance was found in Chinese hamster V-79 cells when they were cocultivated with bronchial explants in the presence of BzaP. The proximate carcinogenic form of BzaP, the 7,8-diol [(+/-)-r7,t8-dihyroxy-7,8-dihydrobenzo[a]pyrene], was 5-fold more potent as a promutagen than the parent compound. Neither BzaP nor the 7,8-diol increased the mutation frequency in V-79 cells when they were cultured without bronchial explants. The mutation frequency was directly related to the binding levels of BzaP to bronchial DNA and the concentratin of either BzaP or the 7,8-diol in the medium.

Adenosine Triphosphatases↗
PubMed1978

Glomangioma of the lung.

An unusual pulmonary tumor was identified on the basis of light and electron microscopic findings as glomangioma. The ultrastructural findings of intracytoplasmic fibrils with dense bodies, electron-dense plaques, pinocytotic vesicles, and basement membranes are consistent with smooth muscle origin. The differential diagnosis between our tumor and other unusual tumors is discussed. The occurrence of a glomangioma in the lung may indicate the existence of pulmonary glomera.

Aged↗
PubMed1978

The respiratory epithelium. V. Histogenesis of lung carcinomas in the human.

One hundred human primary lung carcinomas were studied by light and electron microscopy and by light microscopic histochemistry to demonstrate mucosubstances. The tumors were classified histogenetically and were grouped into three major categories depending on their cell of origin: 1) tumors from basal and/or mucous cells; 2) tumors from neurosecretory cells; and 3) tumors from Clara cells. Most carcinomas (88%) arose from basal and/or mucous cells. These were subdivided into epidermoid carcinomas (21%), combined epidermoid and adenocarcinomas (46%), and adenocarcinomas (21%). The criteria for epidermoid differentiation included the presence of tonofilament bundles, poorly developed endoplasmic reticulum and Golgi apparatus, and well-developed desmosomes. The criteria for adeno differentiation included well-developed endoplasmic reticulum and Golgi apparatus, poorly developed desmosomes, the presence of extracellular and/or intracellular alveoli, and/or other evidence of cellular secretion such as secretory granules. In adenocarcinomas with extracellular alveoli, typical junctional complexes were also present at the luminal aspect where the cell apexes bordered the alveolus. With these criteria, combined epidermoid and adenocarcinomas were the most common type of lung carcinoma. We anticipate that the new data will clarify categories such as small cell anaplastic carcinoma and large cell carcinoma of the World Health Organization classification. In addition, the histogenetic classification of lung tumors may be of value in the future in studies of risk factors, prognosis, prevention, and treatment of lung cancer.

Adenocarcinoma↗
PubMed1978

Studies of the ischemic pancreas in shock.

Exocrine pancreatic tissue from 65 male Sprague-Dawley rats was studied by light and electron microscopy to determine if acute lethal and sublethal alterations seen in the human exocrine pancreas following shock could be duplicated in an animal model. Two models were used: one in which 50% of the blood was withdrawn via cardiac puncture with no reinfusion and another in which the animal was subjected to a hypovolemic episode (40 mm Hg) for 60 minutes, with reinfusion of the blood. Animals were killed at various intervals, and pancreatic tissue was sampled for morphological study. No differences were seen between experimental and control animals by light microscopy. The main subcellular alteration seen using these models was the formation of numerous autophagic vacuoles. From these studies it appears that the alterations seen in the human pancreas in shock can be duplicated in the rat and that a shock model that involves removal of more than 50% of the animal's blood volume is necessary to cause irreversible cell damage to the exocrine pancreas.

Animals↗
PubMed1978

Ultrastructural study on kidney cell injury following various types of shock in 26 immediate autopsy patients.

In acute renal failure in man following shock and trauma, an amazing discrepancy was found between the complete breakdown of renal function and the very modest histological and ultrastructural changes in "immediate autopsy" patients, even in those who sustained septic shock. Although, from this limited number of studies no satisfactory interpretation of the pathogenesis of acute renal failure can be deduced from the structural changes found, the findings do indicate that hypoxia plays a key role in aggravating the structural changes that induce permanent cell damage in man following shock of various etiologies including septic shock.

Adolescent↗
PubMed1978

The respiratory epithelium. I. Human bronchus.

Six morphologic cell types comprise the human bronchial epithelium: basal cells that do not reach the bronchial lumen, neurosecretory cells (Kulchitsky's cells, K-cells, or small granule cells) that rarely reach the lumen, and indifferent cells, mucous cells [small mucous granule cells (SMGC) and mucous goblet cells], ciliated cells, and ciliated-mucous cells that do reach the lumen. Ciliated-mucous cells bearing fully developed cilia and containing mucous granules are seen only occasionally. Three of the cell types that reach the lumen are microvillus covered and do not bear cilia. The microvillus-covered nonciliated cells are: 1) neurosecretory cells, 2) indifferent cells, and 3) mucous cells. Neurosecretory cells contain characteristic dense core granules. Such cells rarely reach the lumen. Indifferent cells are rarely seen. They have a pale cytoplasm and show no evidence of either ciliary or mucous differentiation. Similar cells are observed showing early signs of either ciliary or mucous differentiation or even both types of differentiation in the same cell. Mucous cells comprise the vast majority of microvillus-covered cells. They present either as SMGC with a few small mucous granules or as goblet cells, filled with mucus. These columnar cells are characterized ultrastructurally by dense cytoplasm and a well-developed endoplasmic reticulum and Golgi apparatus. The microvilli are coated with a glycocalyx that binds colloidal iron more avidly than that of either cilia or microvilli of ciliated cells. Possible interrelationships between the different cell types in normal epithelium are discussed.

Bronchi↗
PubMed1978

The respiratory epithelium. II. Hamster trachea, bronchus, and bronchioles.

The normal female hamster respiratory epithelium at five airway levels was characterized with the use of coordinated morphologic and histochemical techniques. Five morphologic cell types were recognized in the trachea, stem bronchi, and primary bronchl: basal cells and neurosecretory cells that were basally located and did not reach the lumen and mucous cells [mucous goblet cells and small mucous granule cells (SMGC)], indifferent cells showing mucous-ciliary differentiation, and ciliated cells that reached the lumen. Two epithelial cell types were observed in the bronchioles, ciliated cells and nonciliated Clara cells, both of which reached the lumen. Mucous cells presented as either SMGC with a few small periodic acid-Schiff-positive granules (diastase-resistant neutral mucosubstances) or as goblet cells, filled with the same material. Mucous cells were columnar, and the cytoplasm was electron-dense and contained a well-developed endoplasmic reticulum and Golgi complex. The microvilli of the mucous cells were coated more thickly with colloidal iron than either the cilia or microvilli of ciliated cells. Approximately one-half the cells in the trachea, bronchi, and bronchioles were ciliated. Ciliated cells containing intracellular ciliated cysts with normal cilia projecting into a closed space or ciliated cells bearing compound cilia were observed infrequently. Neurosecretory cells were rarely observed. These cells contained characteristic dense-core granules.

Animals↗
PubMed1978

The respiratory epithelium. III. Histogenesis of epidermoid metaplasia and carcinoma in situ in the human.

The histogenesis of epidermoid metaplasia and carcinoma in situ was analyzed in human bronchial epithelium. The conclusion is that epidermoid metaplasia and carcinoma in situ can result from conversion of mucous cells. This implies the direct transformation of one type of fully differentiated cell to another. The study therefore emphasizes the differentiation potentialities of the mucous cells that can divide and undergo goblet cell hyperplasia and epidermoid metaplasia. Epidermoid metaplasia is a common reaction to injury in the bronchus. In our series of cases it was especially frequent in patients without neoplastic disease who had undergone intratracheal intubation or tracheostomy and who had been maintained on a respirator in the Shock Trauma Unit, University of Maryland. Future studies will be required to distinguish the difference, if any, between epidermoid metaplasia destined to become malignant carcinoma and that which is not. One difference noted in this study was the absence of overt cornification in epidermoid metaplasia in patients without neoplastic disease.

Bronchi↗
PubMed1978

The respiratory epithelium. VI. Histogenesis of lung tumors induced by benzo[a]pyrene-ferric oxide in the hamster.

Lung tumors were induced in female Syrian golden hamsters by intratracheal instillation of benzo[a]pyrene-Fe2O3. The tumors were characterized with the use of coordinated morphologic and histochemical techniques including electron microscopy. The lung carcinomas were classified according to their presumed cell of origin. Most were derived from mucous cells and/or basal cells, and they were classified as either epidermoid carcinomas or as combined epidermoid and adenocarcinomas. The tumors in the second group (57% of the total number of carcinomas) presented a wide spectrum of epidermoid and adeno components. The epidermoid component was characterized in well-differentiated tumors by the presence of intercellular bridges and/or keratinization. Well-developed desmosomes and numerous bundles of tonofilaments were observed ultrastructurally. In diagnosing adenocarcinoma, one no longer needs to depend on the presence of tubules or gross glandular structures as criteria for diagnosis. The presence of intracellular and/or extracellular alveoli, well-developed Golgi complex, and endoplasmic reticulum and/or evidence of mucous secretion provide more definitive criteria. A tumor composed of neurosecretory cells that morphologically resembled a bronchial carcinoid of man was observed. Nests of uniform, small, polygonal cells with round-to-oval nuclei were seen at the light microscopic level. Dense-core secretory granules 1,100-2,200 A were present in the cytoplasm of the tumor cells. Several fibrosarcomas were observed. The tumors showed a very cellular structure, composed of either densely packed ovoid or spindle-shaped cells. Ultrastructurally, the cells resembled fibroblasts. The results obtained in this study give strong support for a histogenetic classification, i.e., a classification based on the cell of origin.

Adenocarcinoma↗
PubMed1978

The use and application of autopsy in research.

The only limit to the use and application of the autopsy in research is the imagination of the investigator. As pathologists, it would appear that we have really neglected this powerful tool in recent decades and have undersold the potentiality of this method. As we hope to have made evident by the foregoing discussion, the field of research utilizing autopsy tissues is truly as broad as medicine itself, and if developed properly, becomes an indispensable part of the fabric of on-going research in areas of carcinogenesis, environmental disease, atherosclerosis, and aging.

Animals↗