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Crystallization Of Calcium Oxalate And Calcium Phosphate At Supersaturation Levels Corresponding To Those In Different Parts Of The Nephron, Ján Lupták, Hanne Bek-Jensen, Anne-Marie Fornander, Inge Höjgaard, Mari-Anne Nilsson, Hans-Göran Tiselius

Scanning Microscopy

The risk of crystallization in solutions, with a composition corresponding to that of urine in various parts of the nephron, was assessed by studying urine samples containing standardized increments of calcium and oxalate concentrations. The experiments were carried out in salt solutions with and without dialysed urine and the appearance of crystals was detected and measured with a Coulter counter. With increased concentrations of calcium, crystals of calcium phosphate were predominantly formed in solutions with a composition corresponding to that in the proximal and distal tubuli, whereas, calcium oxalate was the primary crystallization product in solutions with a composition corresponding …

Effects Of Acute Acid Loading On The Risk Of Calcium Phosphate And Calcium Oxalate Crystallization In Urine, P. J. Osther, J. Bollerslev, J. R. Nørgård, K. Engel, P. Kildeberg

Scanning Microscopy

The aim of this study was to examine the risk of calcium phosphate and calcium oxalate crystallization during acute acid loading under controlled conditions.

The effects of acute acid loading on rates of renal excretion of calcium, magnesium, phosphate, citrate, oxalate and urine pH were studied in healthy subjects. The risk of calcium phosphate and calcium oxalate crystallization were evaluated by estimates of the ion activity products of calcium phosphate [AP(CaP)-index] and calcium oxalate [AP(CaOx)-index] according to Tiselius. In addition, the risk of brushite [AP(Bru)-index] crystallization was estimated.

An acute acid load administered as ammonium chloride (NH₄Cl) produced …

Changes Of Ion And Water Content Of Mouse Intestinal Cells After Pilocarpine And Isoproterenol Stimulation, Thomas Von Zglinicki, Godfried M. Roomans

Scanning Microscopy

Cytoplasmic monovalent ion and water contents in morphologically defined mice jejuna) cells were measured by X-ray microanalysis in order to gain insight into the cell-type specificity of intestinal electrolyte transport mechanisms. Ion and water contents were measured independently. It was found that in some cases net fluxes of ions and water do not correspond to the assumption of constant osmotic activity of cytoplasmic Na and K ions. Stimulation of secretion with the cholinergic secretagogue pilocarpine resulted in efflux of Cl^- from and influx of K⁺ into crypt enterocytes containing small secretion granula (crypt A cells). No significant changes …

Laser Microprobe Mass Spectrometry In Biology And Biomedicine, S. Eeckhaoudt, L. Van Vaeck, R. Gijbels, R. E. Van Grieken

Scanning Microscopy

An overview is given of laser microprobe mass spectrometry (LMMS) in biology and biomedicine (1989-1993). The present instrumentation and its analytical features are surveyed. Applications are presented with special attention on human and animal tissue samples, as well as plant material. The capabilities of LMMS to study the element distribution in histological sections, to identify the chemical composition of inorganic inclusions and to generate structural information from organic compounds are evidenced.

Ion Microscopy In Biology, George H. Morrison, Isabelle Gay, Subhash Chandra

Scanning Microscopy

Ion microscopy, a mass spectrometry based isotopic imaging technique, is uniquely suited for ion transport-related problems in biological systems. Due to its high sensitivity, it can image the transport and distribution of both major and minor elements (isotopes) at subcellular resolutions. The images of major elements such as K, Na, Cl, etc., can be viewed directly and recorded in real-time from the microchannel plate-fluorescent screen detector of the instrument. The low concentration physiologically important elements, such as Ca, need about one minute of integration for good quality imaging. The isotopic imaging capability of ion microscopy provides a unique approach for …

Use Of In Vitro Systems For X-Ray Microanalysis, Jarin Hongpaisan, Ann-Christin Mörk, Godfried M. Roomans

Scanning Microscopy

The use of X-ray microanalysis in human pathology may require the use of cryoprepared tissue. Often it is impossible to carry out freezing of the tissue in an optimal way, and in addition, it is difficult to carry out experiments in living patients. The use of in vitro systems and cell cultures allows separation of the process of tissue removal and the freezing procedure, and also makes testing of pharmacological or toxic substances possible. In experiments with animal tissue it was shown that incubation in a physiological buffer induced significant changes in the concentrations of Na, K, and Cl. In …

Measurement Of Subcellular Ca2+ Redistribution In Cardiac Muscle In Situ: Time Resolved Rapid Freezing And Electron Probe Microanalysis, Meredith Bond, Mark D. Schluchter, Eva Keller, Christine S. Moravec

Scanning Microscopy

To directly assess the physiological roles of sarcoplasmic reticulum (SR) and miitochondria (MT), we have utilized energy dispersive electron probe microanalysis (EPMA) on ultrathin freeze-dried cryosections from isolated papillary muscles, rapidly frozen at precise time points of the contractile cycle. Using this approach, we can detect redistribution of subcellular Ca²⁺ during the cardiac contractile cycle. Changes in Ca²⁺ of less than 1.0 mmol/kg dry wt can be detected. By determining the variability of the Ca²⁺ measurements in preliminary experiments, we have also demonstrated that it is possible to optimize experimental design, i.e., to predict the number of …

Factors Influencing The Spatial Distribution And Natural History Of Desmognathus Ochrophaeus In West Virginia, Linda D. Ordiway

Theses, Dissertations and Capstones

Desmognathus ochrophaeus, the mountain dusky salamander, is a medium-sized Desmognathine, which inhabits moist woodlands. It is a slender species with a well rounded, slim and tapering tail (Bishop 1967), and 14 costal grooves (Green and Pauley 1987). The average total length is between 70 mm and 100 mm with the tail accounting for approximately half this length (Conant and Collins, 1991). The visual appearance of this salamander is highly variable (figure 1). Most individuals have a distinct light middorsal band with straight edges and darker sides. The colors of the band may vary from yellow, orange, or red to dark …

Considerations For Evaluating Ultraviolet Radiation-Induced Genetic Damage Relative To Antarctic Ozone Depletion, Deneb Karentz

Biology Faculty Publications

Springtime ozone depletion over the Antarctic results in increased UVB in local marine environments. It has been established that decreases in primary productivity occur with decreases in ozone concentrations, but the impact of increased UVB on the functioning and stability of the ecosystem has not yet been determined. Very little has been done to evaluate the potential for genetic damage caused by the increase in UVB, and this type of damage is most significant relative to the fitness and maintenance of populations. An essential problem in evaluating genotoxic effects is the lack of appropriate techniques to sample and quantify genetic …

Comparison Of Dietary Overlap Between Allopatric And Sympatric Geckos, Paul D. Klawinski, R. Kathryn Vaughan, Daniel Saenz, William Godwin

Faculty Publications

Two gecko species, Hemidactylus turcicus and Cyrtopodion scabrum, have been introduced into the Port of Galveston, Texas. While H. turcicus has been established for a longer period of time, the relatively recent introduction of C. scabrum near the entrance of the Port has apparently led to the displacement of H. turcicus in that area. This has resulted in a distribution in which the two populations’ are largely allopatric except for a narrow band of sympatry at the periphery of each of their ranges. We examined stomach contents of both species in allopatry and sympatry in order to determine if …

Ua3/8/1 L.Y. Lancaster Professorship Report, Wku Ogden College Of Science & Technology

WKU Administration Documents

Report of activities by Dr. Blaine Ferrell, L.Y. Lancaster Professor for the year 1993-94, funded by Ogden Foundation.

Impalement Of Marine Turtles (Reptilia, Chelonia: Cheloniidae And Dermochelyidae) By Billfishes (Osteichthyes, Perciformes: Istiophoridae And Xiphiidae), John G. Frazier, Harry L. Fierstine, Sallie C. Beavers, Federico Achaval, Hiroyuki Suganuma, Robert L. Pitman, Yuichiro Yamaguchi, Carlos Ma. Prigioni

Biological Sciences

Billfishes have long been known to impale a great variety of objects, but there are only two brief, obscure records of marine turtles being speared. Details are presented on these two, as well as on two other confirmed records; data from two additional unconfirmed records are also presented. In total, three species of marine turtles are known to have been impaled by three species of billfishes; a fourth species of fish and a fourth species turtle are listed in an unconfirmed case. Records come from the eastern and western Pacific as well as the eastern Atlantic. Of the four confirmed …

Spatial And Temporal Aspects Of Populations Revealed By Mitochondrial Dna, Francis X. Villablanca

Biological Sciences

The evolutionary analysis of DNA sequences bridges phylogenetics and population genetics. Ancient DNA (aDNA) alJows the study of extinct genotypes, populations, and species, as well as dichronic comparisons of extant populations and species. Thus a DNA forges an empirical link between history and two inherently historical fields of research. Fortunately, the conceptual frameworks of phylogenetics and population genetics can easily be extended to encompass advances being made in the study of aDNA.

Reproductive Biology And Early Life History Of Fishes In The Ohio River Drainage, Vol. 2, Larry K. Kay, Robert Wallus, Bruce L. Yeager

Ohio River Fish

No abstract provided.

Role Of The Invertebrate Electrogenic 2na+/H+ Antiporter In Monovalent And Divalent Cation Transport, Gregory A. Ahearn, Jeff Duerr, V. Pennington

Faculty Publications - Department of Biological & Molecular Science

In recent years, an electrogenic 2Na+/1H+ antiporter has been identified in a variety of invertebrate epithelial brush-border membranes of gut, kidney and gill tissues. The antiporter differs significantly in its physiological properties from the electroneutral 1Na+/1H+ antiporter proposed for vertebrate cells. In all invertebrate cells examined, the antiporter displayed a 2:1 transport stoichiometry, responded to an induced transmembrane potential and exhibited a high binding affinity for the divalent cation Ca2+, which acted as a competitive inhibitor of Na+ transport. A monoclonal antibody specific for the crustacean electrogenic antiporter inhibited 2Na+/1H+ exchange, but was without effect on Na+-dependent D-glucose transport. Immunoreactivity …

Field Metabolic Rate And Food Consumption Of Two Sympatric Hummingbird Species In Southeastern Arizona, Donald R. Powers, Timothy M. Conley

Faculty Publications - Department of Biological & Molecular Science

We compared the field metabolic rate (FMR) and behavior around sugar-water feeders of sympatric territorial and non-territorial hummingbirds in the Chiricahua Mountains of southeastern Arizona during July 1987 and 1989. The territorial species was the Blue-throated Hummingbird (Lampornis clemenciae; mean mass 8.77 g) and the non-territorial species the Black-chinned Hummingbird( Archilochusa lexandri; mean mass 3.67 g). FMR (CO2p roduction)a nd watert urnoverw erem easuredu singt he doublyl abeledw ater technique. FMR averaged 81.7 kJ/day (n = 4) in L. clemenciae and 29.1 kJ/day (n = 4) in A. alexandri. Mean mass-specific FMR was higher in L. clemenciae (18.36 ml CO2 …

Pathways Of Intracellular Protein Turnover In Cultured Human Fibroblasts, Sarah Olenick

Dissertations

No abstract provided.

Molecular Phylogenetic Studies Of The Genus Brugia, Hong Xie, O. Bain, Steven A. Williams

Biological Sciences: Faculty Publications

This paper is the first molecular phylogenetic study on Brugia para- sites (family Onchocercidae) which includes 6 of the 10 species of this genus : B. beaveri Ash et Little, 1 9 6 4 ; B. buckleyiDissanaike et Paramananthan, 1961 ; B. malayi (Brug,1927) Buckley, 1960 ; B. pohangi, (Buckley et Edeson, 1956) Buckley, 1960; B. patei (Buckley, Nelson etHeisch,1958) Buckley, 1960 and B. limori Partono et al., 1 9 7 7 . Hha I repeat sequences are 322 nucleotides long, highly repeated, tandemly arranged and unique to the nuclear genomes of the genus Brugia. Hha I repeat sequence data …

Movement Of Axoplasmic Organelles On Actin Filaments From Skeletal Muscle, George M. Langford, Sergie A. Kuznetsov, Dale Johnson, Darien L. Cohen, Dieter G. Weiss

Biology - All Scholarship

It was recently shown that, in addition to the well-established microtubule-dependent mechanism, fast transport of organelles in squid giant axons also occurs in the presence of actin filaments [Kuznetsov et al., 1992, Nature 356:722-725]. The objectives of this study were to obtain direct evidence of axoplasmic organelle movement on actin filaments and to demonstrate that these organelles are able to move on skeletal muscle actin filaments. Organelles and actin filaments were visualized by video-enhanced contrast differential interference contrast (AVEC-DIC) microscopy and by video intensified fluorescence microscopy. Actin filaments, prepared by polymerization of monomeric actin purified from rabbit skeletal muscle, were …

Homosexual Copulations By Male Tree Swallows, Michael P. Lombardo, Ruth M. Bosman, Christine A. Faro, Stephen G. Houtteman, Timothy S. Kluisza

Peer Reviewed Publications

Homosexual courtship behavior in non-human animals is well known (Ford and Beach 1980) and occurs in a wide variety of taxa. However, homosexual copulations, especially between males, are less well known. In birds, males mounting other males have been observed in the colonially breeding Cattle Egret (Bubulcus ibis) (Fujioka and Yamagishi 1981) and Common Murre (Uria aalge) (Birkhead et al. 1985, Hatchwell 1988). Neither Fujioka and Yamagishi (1981) nor Birkhead et al. (1985) and Hatchwell (1988) reported whether cloacal contact occurred during their observations of male-male mountings. Here we describe homosexual copulations by male Tree Swallows …

Energy Conservation By Formation Swimming - Metabolic Evidence From Ducklings, Frank E. Fish

Biology Faculty Publications

No abstract provided.

The Effect Of Food Availability On Time And Energy Expenditures Of Territorial And Non-Territorial Hummingbirds, Donald R. Powers, Todd Mckee

Faculty Publications - Department of Biological & Molecular Science

We studied the time and energy allocations related to territorial behavior in male Blue-throated Hummingbirds (Lampornis clemenciae; about 8.3 g) under conditions of unlimited and restricted food availability. When food was unlimited. territorial males avoided inter-specific aggression, chasing only 11% of the inter-specific intruders (Black-chinned Hummingbirds, Archilochus alexandri; about 3.5 g). Thus, when food was unlimited, inter-specific intruders were able to forage efficiently, meeting their estimated daily energy requirement with ease (27 kJ/day). Conversely, 81% of intraspecific intruders were chased, and intra-specific intruders were able to feed at territorial feeders only when the territorial male was away. Chases of …

A Comparison Of Insulin/Igf 1 And Progesterone-Induced Meiotic Maturation Of Xenopus Laevis Oocytes, Kevin T. Coleman

Master's Theses

No abstract provided.

An Evaluation Of Factors Affecting The Estrous Cycle Of The Djungarian Hamster, Phodopus Sungorus, Roberta W. Ellington

Master's Theses

No abstract provided.

Circulating Plasma Lipoproteins And Hepatic Ultrastructure In The Hibernating Thirteen-Lined Ground Squirrel, Spermophilus Tridecemlineatus, David G. Grecek

Master's Theses

No abstract provided.

Modulation Of Ascending Electrosensory Information By Descending Pathway Stimulation In The Channel Catfish, Lizabeth Scoma

Master's Theses

No abstract provided.

Regulation Of The Na+/H+ Antiport In Xenopus Laevis Oocytes During Meiotic Maturation, Katayoun Rezai

Master's Theses

No abstract provided.

Isolation And Analysis Of A Cdna From The Gag/Protease Region Of The Soybean Retrotransposon, Sire-1, Yi-An Bi

Master's Theses

No abstract provided.

Cellular Mechanisms Of Muscle Fatigue, Robert H. Fitts

Biological Sciences Faculty Research and Publications

Fatigue, defined as the failure to maintain the required or expected power output, is a complex problem, since multiple factors are clearly involved, with the relative importance of each dependent on the fiber type composition of the contracting muscles(s), and the intensity, type, and duration of the contractile activity. The primary sites of fatigue appear to be within the muscle cell itself and for the most part do not involve the central nervous system or the neuromuscular junction. The major hypotheses of fatigue center on disturbances in the surface membrane, E-C coupling, or metabolic events. The cell sites most frequently …

Development And Application Of A Thermistor Current Meter, Carl M. Way, Albert J. Burky, Christine Miller-Way

Biology Faculty Publications

This report provides details for the construction of a hot-bead thermistor current meter which is capable of measuring water velocities on a millimeter spatial scale and for the construction of a compact and accurate calibration system. Hot-bead thermistor current meters can be built with response times of 200 ms capable of measuring velocities between 0.1 and 80 cm s-1. The construction of a sturdy probe for application in lotic systems such as high gradient Hawaiian streams was achieved by the use of heavy-duty acrylic tubing, small stainless steel gas-chromatography tubing, and flexible Tygon spaghetti tubing. An acrylic handle anchors the …