Digital Commons Network^™

The Use Of Organ Cultures To Study Vessel Wall Pathobiology, Edward W. Y. Koo, Avrum I. Gotlieb

Scanning Microscopy

Organ culture of the vessel wall is an useful in vitro method to study vascular cell biology. The intact vessel allows for the study of cell-cell and cell-substratum interactions including the structure and function of the vessel wall matrix. Long term organ cultures of porcine aorta show that neointimal formation is due primarily to cell proliferation of pre-existing intimal smooth muscle cells. Neointimal formation in these cultures is more pronounced in the presence of an endothelium that is turning over. In endothelial wound repair studies, the endothelium of the organ culture shows some important differences when compared to tissue culture …

Characteristics Related To The Incidence Of Osteoporosis In Two Distinct Female Populations, Deborah A. Pyke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Osteoporosis is responsible for approximately 1.3 to 1.5 million fractures per year in the United States. The risk of osteoporosis increases with age, especially among postmenopausal women, and with lifestyle factors such as the use of certain drugs, heavy alcohol consumption, cigarette smoking, high caffeine intake, and sedentary living. Genetic factors that may influence susceptibility to osteoporosis include a positive family history of the disease, or a low weight - for-height ratio. In some cases, race and geographic location may increase or decrease the risk of osteoporosis. Known protective factors include obesity, estrogen replacement therapy, weight bearing exercise, and possibly …

Effect Of Various Growth-Promoting Factors On Preimplantation Bovine Embryo Development In Vitro, Mark Randall Flood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to define the effects of various growth-promoting factors on in vitro embryonic development of in vitro matured and in vitro fertilized bovine embryos. The control medium was a chemically defined medium which improves the possibility of closely determining the in vivo conditions the embryo is actually exposed to. The growth-promoting factors tested in this experiment included transferrin, IGF-I (insulin-like growth factor-one), IGF-II (insulin-like growth factor-two), TGF-𝛼 (transforming growth factor-alpha), TGF-𝛽1 (transforming growth factor-beta1), PDGF (platelet derived growth factor), EGF (epidermal growth factor), NGF (nerve growth factor), and bFGF (basic fibroblast growth factor). Transferrin was …

Factors Affecting The Kinetics Of Light Intensity Adaptation In Marine Phytoplankton, Chunzhi Guo

OES Theses and Dissertations

It has been suggested that the recent light history of phytoplankton and the kinetics of photoadaptation can be used to provide information about the vertical mixing processes in the upper mixed layer. To be useful as a parameter in a model of photoadaptation and vertical mixing, the response of a photoadaptive variable to changes in growth irradiance must be monotonic, significant, and comparable in time rate scale to mixing processes. Previous studies of photoadaptation kinetics have focused on the response of phytoplankton to changes in light intensity under continuous illumination. This dissertation attempts to elucidate the effects of light:dark cycle, …

A Biosystematic Study Of Panus Conchatus (Basidiomycetes; Agaricales), James Edward Johnson

Masters Theses

As part of a biosystematic study of Panus conchatus (Bull.: Fr.) Fr., North American and European herbarium specimens from the Field Museum and the University of Michigan were examined and a description of the taxon prepared. Tissue and single spore isolates were obtained from basidiocarps collected in Illinois. Single and polyspore isolates were obtained from a collection made in Switzerland by R. H. Petersen. Culture mat analyses were completed on several media and the taxonomic value of cultural characters assessed. Based on this study, the identification of somatic cultures by cultural characteristics is unlikely. Single spore isolates from the Illinois …

Charles Rueben Keyes And The History Of Iowa Archaeology, William Green

Journal of the Iowa Academy of Science: JIAS

Charles Reuben Keyes (1871-1951) achieved recognition during his lifetime as the "founding father" of Iowa archaeology, and later assessments confirmed and reemphasized Keyes' stature as Iowa's pioneer archaeologist. The collections and documents Keyes compiled, his interpretive publications, and the records of field work he coordinated have proven more valuable to Midwest and Plains archaeology every year. This article emphasizes Keyes' involvement in the development of professionalism in American archaeology and Iowa’s position in the growth of the discipline from 1920 to 1950. Keyes' contacts with the principal archaeologists of his era ensured Iowa’s involvement in the development of survey methods …

High Voltage Electron Microscopy And Low Voltage Scanning Electron Microscopy Of Human Neoplastic Cell Culture, Marek Malecki

Scanning Microscopy

Improved procedures were developed to correlate cell culture data with the images provided by advanced ultrastructural technologies. These procedures were compatible with the two main types of cellular behavior: adherent, spreading (melanomas, rhabdomyosarcomas) and non-adherent in suspension (leukemias).

The ultrastructure and function of spreading neoplastic cells primarily depend on surface properties of the attaching substrates. Therefore, the films used for cultured cell whole-mount ultrastructural analysis must have adherence features identical to those of standard cell culture vessels. Improved procedures were developed to produce the polystyrene films of required qualities. These films allowed processing of cells for electron microscopy including chemical …

The Use Of Whole Animals Versus Isolated Organs Or Cell Culture In Research, H. Claire Murphy

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

As government regulations for animal care increase in number and complexity, and as animal-rights activists continue to push for decreased use of animals for research, more laboratories have turned to tissue and cell culture for biological research. Initial costs of large animals and escalating maintenance costs have driven some researchers from the use of large animal models. Both models-whole animals for chronic experiments and the use of isolated tissue-can give answers to physiological questions. Cost is certainly a factor that must be considered in the present atmosphere in which funding is so difficult to obtain. However, any information gained in …

Microbial Colonization In Human Periodontal Disease: An Illustrated Tutorial On Selected Ultrastructural And Ecologic Considerations, Charles M. Cobb, William J. Killoy

Scanning Microscopy

The oral cavity is populated by a prodigious microbial flora that exhibits a unique successional colonization of enamel and subgingival root surfaces. A wide range of oral sites provide different ecologic conditions and are, therefore, populated by different commensal microbial combinations. The sequence of microbial colonization, regardless of location within the oral cavity, commences with the acquisition of salivary and/or crevicular fluid-derived pellicle.

As the process of successional colonization of the gingival crevice area proceeds uninterrupted, achieving critical mass between 10 and 21 days, gingivitis becomes evident at a clinical level. However, at a histologic level, gingivitis may be evident …

Achilles Tendon Replacement By A Collagen Fiber Prosthesis: Morphological Evaluation Of Neotendon Formation., Arthur J. Wasserman, Y. Pedro Kato, David Christiansen, Michael G. Dunn, Frederick H. Silver

Scanning Microscopy

Reconstituted type I collagen was processed into fibers which were subsequently severely dehydrated and cyanamide cross-linked. Fibers prepared by this method were stronger and more resistant to degradation than uncrosslinked fibers. When used as a tendon replacement prosthesis, morphological events occurred which were observed by light, scanning, transmission electron microscopy and electron histochemistry.

Resorption was the initial host response to the prosthesis and involved gradual biodegradation. Formation of a host-replacement tendon was the second response. Increased collagen fibril diameters and a transition in the proteoglycan/collagen fibril interactions occurred in the newly developing connective tissue between 3 and 10 weeks post-implantation. …

Barry Morton Gough's Review Of Robert Langdon's The Lost Caravel Re-Explored, Barry Morton Gough

Pacific Studies

No abstract provided.

Osteoclast Features Of Cells That Resorb Demineralized And Mineral-Containing Bone Implants In Rats, Cedo M. Bagi, Scott C. Miller

Scanning Microscopy

The comparative temporal tissue response to demineralized bone matrix powder (DBP) and devitalized mineral containing bone powder (MCP) implanted subcutaneously in rats was studied. The tissue response to implanted DBP followed the well described endochondral osteogenic pathway and included the appearance of osteoblasts and osteoclasts. On the other hand, implanted MCP resulted in the appearance of a large population of giant cells that resorbed the implants. At later times (3-4 weeks), most of the cells in the MCP implants appeared as typical foreign body giant cells with extensive membrane foldings, usually away from bone surface. Some cells did, however, have …

Fermentation Of Cellulosic Substrates In Batch And Continuous Culture By Clostridium Thermocellum, Lee R. Lynd, Hans E. Grethlein, Richard H. Wolkin

Dartmouth Scholarship

Fermentation of dilute-acid-pretreated mixed hardwood and Avicel by Clostridium thermocellum was comparedinbatchandcontinuouscultures.Maximumspecificgrowthratesper hourobtainedon cellulosic substrateswere 0.1inbatchcultureand>0.13incontinuousculture.Cellyields(gramsofcellsper gram of substrate)inbatchculturewere 0.17forpretreatedwoodand0.15forAvicel.Ethanolandacetatewere the mainproductsobservedunderalconditions.Ethanol:acetateratios(ingrams)were approximately1.8:1in batchcultureand generallyslightlylessthan 1:1incontinuousculture.Utilizationofcellulosicsubstrateswas essentially complete in batch culture. A prolonged lag phase was initialy observed in batch culture on pretreated wood; the length of the lag phase could be shortened by addition of cell-free spent medium. In continuousculturewith-5g ofglucoseequivalentper literinthefeed,substrateconversionrelativeto theoreticalrangedfrom0.86ata dilutionrate(D)of0.05/hto0.48ata D of0.167/hforAvicelandfrom0.75 ata D of0.05/hto0.43ata D of0.11/hforpretreatedwood.Atfeedconcentrationsof<4.5g ofglucose equivalentperliter,conversionofpretreatedwoodwas80to90%atD= 0.083/h.Lowerconversionwas obtainedathigherfeedsubstrateconcentrations,consistentwitha limitingfactorotherthancellulose.Free Avicelaseactivitiesof12to84mU/mlwere observed,withactivityincreasinginthisorder:batchceliobiose, batchpretreatedwood< batchAvicel,continuouspretreatedwood< continuousAvicel.Freecellulaseactivity was higheratincreasingextentsofsubstrateutilizationforbothpretreatedwoodandAvicelunderal conditions tested. The results indicate that fermentation parameters, with the exception of free cellulase activity,are essentiallythesame forpretreatedmixedhardwoodandAvicelundera varietyofconditions. HydrolysisyieldsobtainedwithC.thermocellumcellulaseactingeitherinvitroor invivowere comparableto thosepreviouslyreportedforTrichodermareeseion thesame substrates.

Fermentation of dilute-acid-pretreated mixed hardwood and Avicel by Clostridium thermocellum was comparedinbatchandcontinuouscultures.Maximumspecificgrowthratesper hourobtainedon cellulosic substrateswere 0.1inbatchcultureand>0.13incontinuousculture.Cellyields(gramsofcellsper gram of substrate)inbatchculturewere 0.17forpretreatedwoodand0.15forAvicel.Ethanolandacetatewere the mainproductsobservedunderalconditions.Ethanol:acetateratios(ingrams)were approximately1.8:1in batchcultureand generallyslightlylessthan 1:1incontinuousculture.Utilizationofcellulosicsubstrateswas …

Scanning Electron Microscopy In The Study Of Campylobacter Pylori Associated Gastritis, F. Bonvicini, P. Versura, S. Pretolani, G. Gasbarrini, R. Laschi

Scanning Microscopy

The close association between Campylobacter pylori (CP), gastritis and peptic ulcer is now well established. Moreover increasing evidence has been collected of a major etiological role of CP in type B chronic gastritis. For this reason, searching for CP is essential in all patients with upper gastrointestinal symptoms.

Scanning electron microscopy (SEM) is a most reliable technique for studying the distribution of microorganisms and their relationship to the gastric mucosal surface.

The aim of this paper is to compare SEM to other routine methods of detection for CP, such as Giemsa staining on histological sections and Urease Microtiter Test (MT) …

Biochemical Characterization Of The Axolemmal Mitogen For Cultured Schwann Cells, Mark A. Decoster

Theses and Dissertations

The molecule(s) involved at the axon plasma membrane (axolemma) which causes Schwann cells to proliferate has been investigated by three biochemical techniques: 1) Alkaline extraction of axolemma resulted in recovery of 95% of the mitogenic activity and 50% of the protein in the membrane-bound portion of the axolemma. 2) The axonal mitogen for Schwann cells may be associated with heparan sulfate proteoglycans at the axonal surface. Treatment of axolemma with heparitinase, which cleaves the glycosidic bonds of sulfated glycosaminoglycans, allowed mitogenic activity to be solubilized. 3) Treatment of axolemma with heparin, a highly sulfated glycosaminoglycan analogous to heparan sulfate, resulted …

Fine Structure And Organ Culture Of Chick Embryo Dorsal Aorta, C. Ward Kischer, Michael Jaqua

Scanning Microscopy

Embryonic blood vessels have not been grown in organ culture, in a way which might easily submit them to studies of vascular organogenesis. The chick embryo dorsal aorta is easily accessible and relatively simple to explant to culture. Its organ culture may provide a model for wounding and repair of the intima and/or media and provide a model for studies of growth (or maintenance) and differentiation. Fresh dorsal aorta and its organ culture from the chick embryo was characterized morphologically by light microscopy scanning (SEM) and transmission electron microscopy (TEM) from days 4 to 18. Explants were incubated up to …

Attention Deficit Disorder: An Overview, Wiley C. Rasbury

Henry Ford Hospital Medical Journal

No abstract provided.

Determination Of Antibody Levels In Periapical Lesions Against Sixteen Oral Microorganisms By The Elisa Technique, Sammee Lee Jones

Loma Linda University Electronic Theses, Dissertations & Projects

The root canal system, which includes the periapical region of the tooth, may become infected by several types of microorganisms which are normally associated with these tissues. A bacteria-specific antibody response may occur at the local level, where various classes of immunoglobulins have been found and reported in the literature. The purpose of this study was to quantitatively measure locally produced immunoglobulin' levels in periapical lesion abscess materials and to determine the specific reactivity of these antibodies to several microorganisms which are normal flora, as well as being previously associated with the development and pathogenesis of endodontic infections. Periapical lesions …

Effect Of Feeding A Viable Yeast Culture On Ruminal Fermentation Characteristics, Milk Production Response And Apparent Nutrient Digestibility In Holstein Cattle, Mohamed H. Shokair

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Four barren Holstein cows fitted with ruminal fistulas were assigned to each of two dietary treatments in a replicated 2 x 2 Latin square design. Treatments consisted of a basal ration and a basal ration plus 10g/d of a viable yeast culture (Saccharomyces cerevisiae). Cows were fed treatments for a 21-day adaption followed by a 7-day collection period. Total ruminal bacteria, cellulolytic bacteria and protozoa were unaffected by treatment. Feeding the viable yeast culture significantly increased ruminal acetic acid and acetic/propionic ratio. Molar percentage of propionic, isobutyric, isovaleric and valeric acids and rumen ammonia-N levels were significantly reduced …

Policy For Identifying And Assessing The Health Risks Of Toxic Substances, Maine Bureau Of Health

Maine Collection

Policy for Identifying and Assessing the Health Risks of Toxic Substances

by Norman T. Anderson, Environmental Toxicology Program, Division of Disease Control, Bureau of Health (February, 1988).

Contents: Section I: Introduction / Section II: Methods / Section III: Exposure Assessment / Section IV: Hazard Identification / Section V: Hazard Assessment / Section VI: Risk Characterization / List of Figures / List of Tables

Cyanonews (Vol. 4, No. 3, December 1988), Jeff Elhai

CyanoNews

CyanoNews was a newsletter that served the cyanobacteriological community from 1985 to 2003, with content provided by readers (sort of a blog before there were blogs). The newsletter reported new findings from the lab, summaries of recent meetings (often provided by graduate students and post-docs entering the field), positions sought or available, life transitions, a compendium of recent cyanobacteria-related articles, and other items of interest to those who study cyanobacteria.

Fibroblast And Epidermal Cell-Type I Collagen Interactions: Cell Culture And Human Studies, Charles J. Doillon, Frederick H. Silver, Robert M. Olson, Chandrakala Y. Kamath, Richard A. Berg

Scanning Microscopy

Fibroblast and epidermal cell-type I collagen sponge interactions were studied in cell culture as well as in humans. In cell culture, fibroblasts were observed to migrate and proliferate throughout a type I collagen sponge containing either hyaluronic acid (HA) or fibronectin (FN). Fibroblasts accumulated in the center of the pores in sponges containing HA and appeared to surround themselves with newly synthesized extracellular matrix. In sponges containing FN, fibroblasts attached to and elongated along the collagen fibers of the sponge. In the absence of FN or HA protein synthesis of fibroblasts appeared to be inhibited by the presence of the …

The Role Of Scanning Electron Microscopy In Periodontal Research, A. Carrassi, S. Abati, G. Santarelli

Scanning Microscopy

During recent years a great amount of research has led to a better understanding of the etiology, pathogenesis and pattern of progression of periodontal diseases. Scanning electron microscopy (SEM) has contributed to this improvement, mainly with respect to histology of periodontal tissues, the description of the morphology and distribution of bacteria on the exposed root surface, analysis of the host-parasite interactions on the gingival pocket wall, and morphological evaluation of root treatment. This review deals with all these topics. Unusual types of SEM research are also described and discussed. Uncommon sample preparation techniques for SEM in periodontal research are described. …

Hyperthyroidism Due To A Thyrotropin-Secreting Pituitary Microadenoma, Jeffrey A. Jackson, Mitchell Smigiel, John F. Green Jr.

Henry Ford Hospital Medical Journal

A 52-year-old man presented with elevated thyroid hormone levels and an inappropriately normal serum thyrotropin (TSH) (4.0 μU/mL: normal 0.5 to 6.0 μU/mL). Computed tomography suggested an intrasellar mass without radiographic sellar enlargement. Serum alpha-subunit was elevated with flat responses of both alpha-subunit and TSH to thyrotropin-releasing hormone. Transsphenoidal adenomectomy resulted in clinical and biochemical cure with subsequent development of hypothyroidism with otherwise preserved anterior pituitary function. Pathologic studies demonstrated an 8 mm typical thyrotroph cell adenoma. Early diagnosis of such tumors requires a high index of clinical suspicion and may be facilitated in the future by utilization of highly …

Ion And Water Retention By Permeabilized Cells, Carlton F. Hazlewood, Miklos Kellermayer

Scanning Microscopy

Nonionic detergents, Triton X-100 and Brij 58, removed, within 2-5 minutes, lipid membrane of suspended thymus lymphocytes and monolayer H-50 cells grown in culture. Studies of hydration, ionic asymmetry, and ionic and protein release kinetics were conducted on these membraneless cellular preparations. The hydration of nuclei isolated by Triton X-100 procedures appears to be influenced strongly by the monovalent ionic concentration of the buffer bathing the organelles. The putative monovalent ionic concentration of the cellular aqueous phase (i.e., 150 meq/L) caused nuclei to swell and coalesce. Monovalent ionic concentrations of 30 meq/L or less caused minimal changes in volume and …

Louisiana Agriculture Magazine, Fall 1987, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

Surface Morphology Of Human Airway Mucosa: Normal, Carcinoma Or Cystic Fibrosis, P. K. Jeffery, A. P. R. Brain

Scanning Microscopy

The study presents preliminary qualitative findings of an investigation of grossly normal main and lobar bronchi at sites distant to well circumscribed tumour (n=15), adjacent to tumour (n=5) or of airways obtained during heart/lung transplantation in patients with cystic fibrosis (CF, n=3). In the normal airways the surface epithelium was on average 50 𝝁m thick, pseudostratified and rested on a roughly contoured basement membrane. A variety of cell types were identified although many were obscured by a dense covering of cilia, occasionally interrupted by foci of squamous metaplasia. Submucosal gland structure was observed in chance vertical fractures of the airway …

Scanning Electron Microscopy Of Oral Mucosa In Vivo And In Vitro: A Review, Kristina Arvidson, Roland C. Grafström, Anders Pemer

Scanning Microscopy

The oral mucosa is classified by function into lining, masticatory and specialized oral mucosa, with regional structural adaptation. In this review, the surface structures of the human oral mucosa have been studied in the scanning electron microscope (SEM). Regional variations in regard to keratinization, cell arrangements and microplications with related specific structures observed in SEM are described and correlated with the appearance of similar areas observed in the light microscope. Furthermore, human oral tissue and cell cultures have also been studied. These systems offer usable and complementary models for performing similar studies in vitro under controlled experimental conditions. We now …

The Role Of The Cytoskeleton In Endothelial Repair, Avrum I. Gotlieb, Michael K. K. Wong, Patricia Boden, Alan Choo Fone

Scanning Microscopy

The injured endothelium undergoes rapid repair of areas of cell desquamation in order to maintain the structural integrity of the endothelial surface. Endothelial repair involves a series of processes which include endothelial cell spreading, translocation, and proliferation. These processes are well defined events which occur sequentially in time. Spreading and translocation are mediated by the cell cytoskeleton - F-actin microfilaments and microtubules and associated centrosomes. The regulation of these processes is complex and is likely due to soluble factors present at the site of injury which are released from activated endothelial cells, platelets, the subendothelial substratum, activated serum factors, and …

Microbial Degradation Of Oxalate In The Gastrointestinal Tracts Of Rats, Steven L. Daniel

Faculty Research & Creative Activity

Rates of oxalate degradation by mixed bacterial populations in cecal contents from wlld rats ranged from 2.5 to 20.6 µmol/g (dry weight) per h. The oxalate-degrading activity in cecal contents from three strains of laboratory rats (Long-Evans, Wistar, and Sprague-Dawley) from four commercial breeders was generally lower, ranging from 1.8 to 3.5 µmollg (dry weight) of cecal contents per h. This activity did not increase when diets were supplemented with oxalate. Wben Sprague-Pawley rats from a fifth commercial breeder were fed an oxalate diet, rates of oxalate degradation in cecal contents increased from 2.0 to 23.1 µmollg (dry weight) per …