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Species Recognition In Wild-Caught Peromyscus Californicus And Peromyscus Boylii (Rodentia Cricetidae), Sue M. Abraham Jun 1991

Species Recognition In Wild-Caught Peromyscus Californicus And Peromyscus Boylii (Rodentia Cricetidae), Sue M. Abraham

Theses, Dissertations, and Projects

Experiments were performed to compare homospecific and heterospecific species choice in sympatric populations of Peromyscus californicus and P. boylii. Mate selection performance of males and females were also compared. For both species there was no significant difference between males and females in mate selection performance, and selection appeared to be random. Female P. boylii showed the highest preference for its own species as indicated by the amount of time spent in the homospecific chamber, but this choice was not statistically significant. When data for the two species are combined, the percent of time in the homospecific chamber is significantly different …


Anticarcinogenic, Antitumor, And Antifungal Properties Of Allium Sativum (Garlic), Padma P. Tadi Jun 1991

Anticarcinogenic, Antitumor, And Antifungal Properties Of Allium Sativum (Garlic), Padma P. Tadi

Loma Linda University Electronic Theses, Dissertations & Projects

In this study the antimutagenic/anticarcinogenic, immune enhancing, antitumor and antifungal effects of a crude extract and organosulfur compounds of garlic were determined. Diallyl sulfide (DAS), and ajoene each at 100 /xg/ml, and garlic extract (GE, 12.5 mg/ml) inhibited rat liver 9000 X g supernatant (S- 9) dependent mutagenesis in Salmonella typhimurium TA100 induced by either aflatoxin B1 (AFB^ or benzo[a]pyrene (B[a]P). The garlic compounds were shown to inhibit the binding of [3H]AFB1 to calf thymus DNA and the formation of specific AFB1-DNA adducts. These effects on mutagenesis and DNA binding correlated with an inhibition of …


Separate Sex-Influenced And Genetic Components In Spontaneously Hypertensive Rat Hypertension, Monte E. Turner, Mark L. Johnson, Daniel Ely Jun 1991

Separate Sex-Influenced And Genetic Components In Spontaneously Hypertensive Rat Hypertension, Monte E. Turner, Mark L. Johnson, Daniel Ely

Biology Faculty Research

Previous results from our laboratory indicated two major genetic components of spontaneously hypertensive rat (SHR) hypertension, an autosomal component and a Y chromosome component. Two new substrains, SHR/a and SHR/y, were developed using a series of backcrosses to isolate each of these components. The SHR/a substrain has the autosomal loci and X chromosome from the SHR strain and the Y chromosome from the Wistar-Kyoto (WKY) rat strain. The SHR/y substrain has only the Y chromosome from the SHR and autosomal loci and X chromosome from the WKY strain. Throughout these breeding programs parents were chosen at random without selection for …


Androgen Receptor And The Testes Influence Hypertension In A Hybrid Rat Model, Daniel Ely, Ron Salisbury, Disha Hadi, Monte E. Turner, Mark L. Johnson Jun 1991

Androgen Receptor And The Testes Influence Hypertension In A Hybrid Rat Model, Daniel Ely, Ron Salisbury, Disha Hadi, Monte E. Turner, Mark L. Johnson

Biology Faculty Research

The objective of this study was to determine if males with a deficient androgen receptor would develop hypertension when crossed with a hypertensive parent. Female King-Holtzman rats (n = 15), heterozygous for the testicular feminization (Tfm) gene, were crossed with male spontaneously hypertensive rats (SHR), and blood pressure was measured weekly from 5-14 weeks in the F1 hybrid males. Approximately 50% of the F1 hybrid males were Tfm males and androgen receptor-deficient, and 50% were normal. Blood pressure in the parent King-Holtzman males, Tfms, and female rats was also followed for the same time period. The F1 normal male hybrids …


Elemental Mapping Of Cryosections From Cnidarian Nematocytes, Karl Zierold, Pierre Tardent, Sergey V. Buravkov May 1991

Elemental Mapping Of Cryosections From Cnidarian Nematocytes, Karl Zierold, Pierre Tardent, Sergey V. Buravkov

Scanning Microscopy

The distribution of elements in stinging capsules containing cells called nematocytes is shown by pseudocoloured maps representing the X-ray intensity collected from freeze-dried cryosections. This method provides a distinct overview in addition to the quantitative evaluation of single X-ray spectra. Selected examples illustrate the elemental compartmentation in various cnidarian animals. In particular the matrix of capsules in Hydra vulgaris contains high amounts of K in comparison to the tubule, the surrounding capsule wall and the cytoplasm, whereas in Actinia eguina capsules have either high concentration of Ca or Mg, the latter accompanied by S.


Primary Productivity And Species Composition Of A Reconstructed Wetland In Eastern Kentucky, Eric C. Webb May 1991

Primary Productivity And Species Composition Of A Reconstructed Wetland In Eastern Kentucky, Eric C. Webb

Morehead State Theses and Dissertations

A thesis presented to the faculty of the Department of Biological and Environmental Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Eric C. Webb on May 19, 1991.


An Analysis Of The Anatomical Projection From The Mzi To The Dmcg Using Hrp Histochemistry: Comparison Between Male And Female Rats, Scott E. Preusen '91 May 1991

An Analysis Of The Anatomical Projection From The Mzi To The Dmcg Using Hrp Histochemistry: Comparison Between Male And Female Rats, Scott E. Preusen '91

Honors Projects

Anatomical and behavioral studies indicate that the dorsal Midbrain Central Grey (dMCG) and the Ventromedial Nucleus of the hypothalamus (VMH) are the principle brain structures that function in mediating sexual behavior in the female rat. Recently, the medial portion of the Zona Incerta (mZI) has been implicated as an additional brain structure that regulates sexual receptivity (lordosis) in the female rat. When the mZI of the female was destroyed via intracerebral injections with the neurotoxin, ibotenic acid, by Dornan et al. (1991), they reported that lordosis behavior was shown to be attenuated. Presently, little is known about the role of …


The Effects Of Bilateral Injections Of Neuropeptide K Into The Medial Preoptic Area On Male Rat Copulatory Behavior, Peter Malen '91 May 1991

The Effects Of Bilateral Injections Of Neuropeptide K Into The Medial Preoptic Area On Male Rat Copulatory Behavior, Peter Malen '91

Honors Projects

The first mammalian neuropeptide to be characterized was substance P (sP) , and it is now recognized that sP is a member of a structurally related family of peptides, the tachykinins. Extensive studies have demonstrated. that sP and some related tachykinin peptides play key roles as neurotransmitters and neuromodulators. The synthesis of different members of the tachykinin family is in part due to the modifications' of three sP-encoding preprotachykinin (PPT) mRNA's that are derived from a single sP gene. At least four tachykinin peptides can be synthesized as a result of these differential modifications including sP, neurokinin A, neuropeptide and …


Molecular Genetic Analysis Of The Interaction Between The Bacterial Pathogen Xanthomonas Campestris Pv. Vesicatoria And The Tomato Plant, Peter M. Antall May 1991

Molecular Genetic Analysis Of The Interaction Between The Bacterial Pathogen Xanthomonas Campestris Pv. Vesicatoria And The Tomato Plant, Peter M. Antall

Senior Scholar Papers

X. campestris pv. vesieatoria (Xcv) Is a bacterial pathogen of tomato and pepper. Xcv is able to infect most tomato lines. causing bacterial spot disease. which can lead to death. A strain of Xcv exists. however. which elicits a resistance response In a particular tomato line. ThIs avirulent strain carries a single locus. the aviru1ence gene avrRxv, whIch specifies the resistance inducing activity. Accordlng to Flor's gene for gene model, a corresponding gene must exist in the resistant plant. Evidence exists for this gene but it has not yet been cloned. In this study, the role ofthe avrRxv gene product …


Intracerebral Injections Of Substance P Fragments (5-11) And (1-7) Into The Dorsal Midbrain Central Gray Have No Effects On Lordosis Behavior In The Female Rat, Jodi K. Block '91 May 1991

Intracerebral Injections Of Substance P Fragments (5-11) And (1-7) Into The Dorsal Midbrain Central Gray Have No Effects On Lordosis Behavior In The Female Rat, Jodi K. Block '91

Honors Projects

Substance P (sP), a neuroactive peptide, has now been implicated in a wide range of behaviors. One in particular is female rat sexual behavior. Recently, it has been shown that bilateral injections of sP into the dorsal midbrain central gray (dMCG) of estrogen-primed female rats facilitate sexual behavior (lordosis). Uncertainty remains, however, concerning the mode of action of synaptically released sP. Indeed, most of our understanding of sP activity has revealed that its full structural sequence is not needed for biological activity. This has led to speculation that sP may be processed into one or more types of fragments before …


The Future For Recreational Fishing Final Report Of The Recreational Fishing Advisory Committee, Recreational Fishing Advisory Committee May 1991

The Future For Recreational Fishing Final Report Of The Recreational Fishing Advisory Committee, Recreational Fishing Advisory Committee

Fisheries Management Papers

This report discusses: What Recreational fishing means to Western Australia's estimated 300,000 fishers. Conservation and equality in catch sharing was at the heart of the Committee's investigations into developing strategies for the future management of important recreational fish stocks.


Bird Populations In Logged And Unlogged Western Larch/Douglas-Fir Forest In Northwestern Montana, Bret W. Tobalske, Richard L. Hutto, Raymond C. Shearer May 1991

Bird Populations In Logged And Unlogged Western Larch/Douglas-Fir Forest In Northwestern Montana, Bret W. Tobalske, Richard L. Hutto, Raymond C. Shearer

Biological Sciences Faculty Publications

Of 32 species of abundant breeding birds, populations of 10 species differed significantly between small cutting units and adjacent uncut forest. Foliage foragers and tree gleaners were less abundant in cutting units, while flycatching species and ground foragers were more common there. Of nesting guilds, conifer tree nesters were least abundant in cutting units, and ground nesters were more common there. Results suggest that bird management should consider diverse community-level habitat needs and that if maintenance of tree-dependent species is important, broadleaf trees and snags of all species should be retained.


Factors Affecting Seeds In A Sagebrush-Steppe Ecosystem And Implications For The Dispersion Of An Annual Plant Species, Cheatgrass (Bromus Tectorum L.), Michael Ira Kelrick May 1991

Factors Affecting Seeds In A Sagebrush-Steppe Ecosystem And Implications For The Dispersion Of An Annual Plant Species, Cheatgrass (Bromus Tectorum L.), Michael Ira Kelrick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I investigated how shrub-induced spatial heterogeneity influenced and was manifested by a representative ground-story plant species at a sagebrush-steppe site in southwestern Wyoming. The dispersion of cheatgrass (Bromus tectorum) reflected differences between undershrub (higher plant densities) and interspace (between shrubs, supporting lower densities) microenvironments, hence the population ecology of this annual species served as a biological probe of shrub-associated patch structure in this community. Since cheatgrass is an annual, factors affecting the seed portion of its life cycle were of special interest. First, attributes of the above- and below-ground seed pool were characterized. The environment-wide seed depositional pattern …


Reproductive Strategies Of Northern Goshawks And Cooper's Hawks In North-Central New Mexico, Patricia L. Kennedy May 1991

Reproductive Strategies Of Northern Goshawks And Cooper's Hawks In North-Central New Mexico, Patricia L. Kennedy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I assumed that the reproductive strategies of the two Accipiter species investigated in this study, the northern Goshawk (A. gentilis) and the Cooper's hawk (A. cooperii), would be similar to the strategies of other monogamous raptors with sex role partitioning. Any differences in the species' reproductive strategies, particularly hunting strategies, were expected to be a function of their size differences. Contrary to predictions, results indicated that, in north-central New Mexico during brood rearing, both species had similar hunting strategies and utilized similar prey species. These results also indicated that the reproductive strategies of the Cooper's hawk …


Study Of Ferredoxin And Flavodoxin From Tobacco Leaves And Roots Under Normal And Iron-Stressed Conditions, I-Jen Huang May 1991

Study Of Ferredoxin And Flavodoxin From Tobacco Leaves And Roots Under Normal And Iron-Stressed Conditions, I-Jen Huang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I purified tobacco leaf ferredoxin from normal and iron-stressed leaves. The oxidized form of ferredoxin from normal leaves had absorption maxima at 268, 327, and 422 nm and a shoulder at 463 nm. The oxidized form of ferredoxin from iron-stressed leaves had absorption maxima at 268 and 329 nm but no absorption maxima in the 400-nm range. Higher ferredoxin content was found with higher chlorophyll content in leaves of the same age.

A protein in tobacco root extract was isolated and found to serve as an electron carrier for ferredoxin-requiring nitrite reduction. This protein had a molecular weight and antigenic …


The Hepatic Microcirculation In Experimental Cirrhosis A Scanning Electron Microscopy Study Of Microcorrosion Casts, E. Gaudio, L. Pannarale, M. Ripani, P. Onori, O. Riggio Apr 1991

The Hepatic Microcirculation In Experimental Cirrhosis A Scanning Electron Microscopy Study Of Microcorrosion Casts, E. Gaudio, L. Pannarale, M. Ripani, P. Onori, O. Riggio

Scanning Microscopy

The experimental model of liver cirrhosis induced by intragastric administration of CCl4 reproduces not only the histological picture of the postnecrotic cirrhosis but also its pathophysiological features.

Corrosion casts of livers affected by CCl4-induced cirrhosis show the loss of the lobular pattern. Once the cirrhosis has completely developed, the whole microvascular bed appears to be composed of groups of sinusoid nodules of diameters varying between 0.3 and 1.5 mm.. Pre- and post-sinusoidal vessels and anastomoses between the former and the latter are mainly located at the perinodular spaces.

This microvascular situation modifies the normal perfusion gradient within …


Retinal Changes In A Mutant Form Of Goldfish With Megalophthalmia, David T. Yew, Winnie W. Y. Li, C. Au, H. L. Choi, Q. D. Yang, Patrick K. H. Chan Apr 1991

Retinal Changes In A Mutant Form Of Goldfish With Megalophthalmia, David T. Yew, Winnie W. Y. Li, C. Au, H. L. Choi, Q. D. Yang, Patrick K. H. Chan

Scanning Microscopy

The retinal changes of a mutant strain of goldfish with megalophthalmia were studied by histology, electron microscopy and biochemistry. Changes in the morphology of the pigment epithelium, decrease in number of photoreceptors, thinning out of retinal layers and the existence of spaces in the retina were all features as the eyes grew in size. Invasion of macrophages was also evident in the retina. A decrease in leucine uptake per milligram of retina was also detected as the eye grew beyond 0.8 millilitre in volume. These changes, although related to volume changes (i.e., growth) of the eyes, were found to have …


Theodore Alvin Hall: A Biographical Sketch And Personal Appreciation, Brij L. Gupta Apr 1991

Theodore Alvin Hall: A Biographical Sketch And Personal Appreciation, Brij L. Gupta

Scanning Microscopy

As the first in a series of two papers contributed on the occasion of a special program held at the Scanning Microscopy/1989 meeting in Salt Lake City in honour of Dr. T.A. Hall, and in recognition of his achievements for biological electron probe X-ray microanalysis, this paper provides a biographical sketch of Dr. Hall, as well as a bibliography.


Vitellogenesis In Hyalomma Dromedarii (Acari: Ixodidae): A Model For Analysis Of Endocrine Regulation In Ixodid Ticks, Martin E. Schriefer Apr 1991

Vitellogenesis In Hyalomma Dromedarii (Acari: Ixodidae): A Model For Analysis Of Endocrine Regulation In Ixodid Ticks, Martin E. Schriefer

Theses and Dissertations in Biomedical Sciences

The egg yolk proteins, vitellins, and their hemolymph precursors, vitellogenins, were characterized in the ixodid tick Hyalomma dromedarii. Three vitellins were identified. The high molecular weight vitellins, VN A and VN B, were composed of seven homologous molecular weight subunit polypeptides, VN 1-7. VN A appears to be a dimeric form of VN B. VN C was composed of single polypeptide. Low levels of vitellogenin, were identified in western immunoblots utilizing antibody raised against purified vitellin. Adult protein and polypeptide profiles, including vitellin and vitellogenin, were characterized as a function of sex, tissue and reproductive development. Quantitative assessment of the …


Fertilization And Mouse Embryo Development In The Presence Of Midazolam, Maria Leavitt Apr 1991

Fertilization And Mouse Embryo Development In The Presence Of Midazolam, Maria Leavitt

Biological Sciences Theses & Dissertations

The development of mouse embryos in vitro has provided a unique opportunity for the study of cellular differentiation and the influence of various agents on differentiation. Midazolam is administered for conscious sedation in the recovery of human ova. In the Norfolk IVF Program, midazolam is found in varying concentrations in follicular fluid. Mouse embryo formation and development has been used to test midazolam's effect on fertilization and early development as a model of human in vitro fertilization and development. Midazolam' s effects were studied using varying doses of midazolam on (1) in vivo fertilization and subsequent cell division, and (2) …


Ultrastructure Of Coronary Arterial Endothelium In Atherosclerotic Swine Suggests Lipid Retro-Endocytosis, Keith A. Robinson, Robert P. Apkarian Mar 1991

Ultrastructure Of Coronary Arterial Endothelium In Atherosclerotic Swine Suggests Lipid Retro-Endocytosis, Keith A. Robinson, Robert P. Apkarian

Scanning Microscopy

During experimental atherosclerosis, arterial endothelial cells show characteristic ultrastructural changes including the appearance of increased numbers of plasmalemmal and cytoplasmic vesicles. These structures have been shown by tracer studies to participate in the transcellular transport of low-density lipoprotein cholesterol and β-very-low-density lipoprotein cholesterol from the arterial lumen into the abluminal extracellular matrix. Although this probably represents the major lipid transport pathway, other forms of transport may exist. We document the presence of apparent lipid structures averaging approximately 300 nm in diameter at or near the luminal surface of coronary arterial endothelium of atherosclerotic miniature swine. The structures exhibited a particulate …


Ted Hall And The Science Of Biological Microprobe X-Ray Analysis: A Historical Perspective Of Methodology And Biological Dividends, Brij L. Gupta Mar 1991

Ted Hall And The Science Of Biological Microprobe X-Ray Analysis: A Historical Perspective Of Methodology And Biological Dividends, Brij L. Gupta

Scanning Microscopy

This review surveys the emergence of electron probe X-ray microanalysis as a quantitative method for measuring the chemical elements in situ. The extension of the method to the biological sciences under the influence of Ted Hall is reviewed. Some classical experiments by Hall and his colleagues in Cambridge, UK, previously unpublished, are described; as are some of the earliest quantitative results from the cryo-sections obtained in Cambridge and elsewhere. The progress of the methodology is critically evaluated from the earliest starts to the present state of the art. Particular attention has been focused on the application of the method in …


Three-Dimensional Morphological Analysis Of Nerve Cells By Scanning Electron Microscopy. A Review, O. J. Castejón Mar 1991

Three-Dimensional Morphological Analysis Of Nerve Cells By Scanning Electron Microscopy. A Review, O. J. Castejón

Scanning Microscopy

The present review provides a rational and new approach to study the three-dimensional morphology of nerve cells in situ at both cellular and macromolecular levels, by means of conventional (SEM) and high resolution scanning electron microscopy (HRSEM). The slicing and ethanol-cryofracturing methods, the freeze-fracture SEM method and tissue preparation for HRSEM have been described. Nerve cell outer surface, axon hillock and initial axon segment, axonal collateral ramifications and dendritic processes were visualized either by the slicing technique or the cryofracture method displaying neuronal geometry in situ. The cleavage plane occurred at the satellite neuroglial sheath exposing somatic hidden surfaces of …


The Mayfly Newsletter, Peter M. Grant Mar 1991

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Three-Dimensional Morphology Of Cerebellar Protoplasmic Islands And Proteoglycan Content Of Mossy Fiber Glomerulus: A Scanning And Transmission Electron Microscope Study, O. J. Castejón, H. V. Castejón Feb 1991

Three-Dimensional Morphology Of Cerebellar Protoplasmic Islands And Proteoglycan Content Of Mossy Fiber Glomerulus: A Scanning And Transmission Electron Microscope Study, O. J. Castejón, H. V. Castejón

Scanning Microscopy

The present review summarizes the outer and inner surface features of mossy fiber glomeruli in vertebrate cerebellar granular layer as seen by conventional scanning electron microscopy (SEM) and SEM freeze-fracture method. The intracortical trajectory of mossy fibers and their synaptic contacts with granule cell dendrites were traced by the slicing and freeze-fracture techniques revealing the radial distribution of granule cell dendrites around the central mossy rosette. The "en passant" nature of mossy fiber synaptic contacts and the participation of Golgi cell axonal ramifications were demonstrated. The results obtained were compared with available light and transmission electron microscopy data. The freeze-etching …


Alpha-Particle Irradiation-Induced Change In Bronchopulmonary Macrophage Morphology, In Vitro, T. M. Seed, G. K. Niiro Feb 1991

Alpha-Particle Irradiation-Induced Change In Bronchopulmonary Macrophage Morphology, In Vitro, T. M. Seed, G. K. Niiro

Scanning Microscopy

Bronchopulmonary macrophages, isolated from canine lungs by saline lavage and grown in tissue culture for short periods, were acutely irradiated with a range of doses of either Americium-241 alpha particles (0.03-48 Gy) or 250 keV x-rays (0.5-24 Gy). Following a 24-hour reincubation and "expression" period, cells were examined for radiation-induced changes in overall viability, as well as in cell morphology and ultrastructure. Results indicated that neither quality of radiation had much effect on cell viability over dose ranges examined, but substantial changes in cell volume, surface topography, and cytoplasmic features were noted, especially in the alpha-particle-irradiated specimens. Results support the …


A Scanning Electron Microscopic Morphological And Semi-Quantitative Evaluation Of Rat Stomach Treated With Colloidal Bismuth Subcitrate And Alcohol, C. Winters, S. M. Hinsull, Z. Gregory Feb 1991

A Scanning Electron Microscopic Morphological And Semi-Quantitative Evaluation Of Rat Stomach Treated With Colloidal Bismuth Subcitrate And Alcohol, C. Winters, S. M. Hinsull, Z. Gregory

Scanning Microscopy

Scanning electron microscopy was utilised to study the effect of absolute alcohol on the normal morphology of the rat stomach, together with the gastroprotective actions of colloidal bismuth subcitrate. Studies on normal gastric morphology revealed that the major portion of the stomach was covered by a protective coating of mucus. However, there was considerable variation in the integrity of the mucosal surface of the control animals, with the loss of surface epithelial cells in some regions which may account for the variation in response to necrotising agents. The long-term administration of the gastrocytoprotective agent colloidal bismuth subcitrate resulted in a …


The Response Of The Tracheal Epithelium To Concomitant Cis-Diamminedichloroplatinum (Ii) And Radiation. An Electron Microscopic Study In Rabbits, C. H. Håkansson, M. Albertsson, M. Palmegren, J. Ranstam Feb 1991

The Response Of The Tracheal Epithelium To Concomitant Cis-Diamminedichloroplatinum (Ii) And Radiation. An Electron Microscopic Study In Rabbits, C. H. Håkansson, M. Albertsson, M. Palmegren, J. Ranstam

Scanning Microscopy

The ciliated epithelium of the rabbit trachea was irradiated with daily fractions of 2 Gy up to an accumulated dose of 20 Gy (total dose: 2, 6, 10, 16, or 20 Gy). Fifteen to forty-five minutes before the start of each irradiation 0.3 mg Cis-diamminedichloroplatinum (cis-DDP) was given by intraperitoneal injection to each rabbit. Examinations were carried out 1-10 days after each fractionation schedule, when specimens were taken for morphological investigations.

Scanning electron microscope (SEM) examination showed a gradual development of ciliary damage, from blebs on the cilia to swollen tips, broken and bent cilia and finally an epithelial injury …


Timed Acid Bath Effects On Kidney Podocytes Prepared For Scanning Electron Microscopy, B. J. Moore, K. R. Holmes Feb 1991

Timed Acid Bath Effects On Kidney Podocytes Prepared For Scanning Electron Microscopy, B. J. Moore, K. R. Holmes

Scanning Microscopy

In perfusion fixation of dog kidney glomeruli, observation of tear fractured surfaces by scanning electron microscopy reveals the deposition of "debris" on the surface of glomerular visceral epithelium (podocytes) that is not deposited on other kidney tissue surfaces. It is of concern to remove this debris without damage to tissue surfaces. A 5 minute bath in 8N HCI (hydrochloric acid) following postfixation in 1% OsO4 (osmium tetroxide) removes only some of the debris. A 10 minute acid bath removes this debris without visible damage to podocyte surface structures such as cilia, plicae or blebs. A 20 minute acid bath …


Transplacental Cardiotoxicity Of Cocaine: Atrial Damage Following Treatment In Early Pregnancy, Jacques Gilloteaux, John P. Dalbec Feb 1991

Transplacental Cardiotoxicity Of Cocaine: Atrial Damage Following Treatment In Early Pregnancy, Jacques Gilloteaux, John P. Dalbec

Scanning Microscopy

Using light, transmission (TEM) and scanning (SEM) electron microscopy, cocaine-induced defects were observed in hamster atria. Compared with controls, the treated atria from neonates show endocardial and myocardial damages as the atrial walls thicken. SEM micrographs show intensive blebbing, damage and incomplete coverage of myocardium by the endocardial endothelium. TEM data demonstrate blebs, thinning, and other endothelial cell injuries and complement the SEM findings. Areas of endothelial sloughing may facilitate the formation of luminal and mural thrombi as noticed in many neonatal atria. Adjacent subendocardial myocardial cells display contraction bands, swellings, and vacuolizations. Local and large areas of damaged myocardial …