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Full-Text Articles in Life Sciences
The Influence Of Incubation Conditions On Oxygen Consumption During The Development Of Pantherophis Guttatus, Celeste Gallardo
The Influence Of Incubation Conditions On Oxygen Consumption During The Development Of Pantherophis Guttatus, Celeste Gallardo
Electronic Theses and Dissertations
The flexible shell of some oviparous reptiles has led to differences in nutrient mobilization and water relations when compared to their rigid-shelled counterparts. Flexible-shelled eggs gain more water during development, and because of the shell structure, yolk calcium content is higher than that of eggshells. When water availability is altered for reptiles with flexible-shelled eggs, differences in both energy and nutrient utilization are observed. This study was designed to determine the baseline metabolic rate during development for the snake, Pantherophis guttatus under normal conditions, and to observe how changes in eggshell calcium and water availability impact embryonic oxygen consumption. Eggshell …
Estradiol Modulation Of Calcium Dynamics In Pituitary Mmq Lactotroph Cells, Monika Pauckova
Estradiol Modulation Of Calcium Dynamics In Pituitary Mmq Lactotroph Cells, Monika Pauckova
Electronic Theses and Dissertations
Pituitary lactotrophs are excitable cells that exhibit spontaneous, calcium influx triggering prolactin (PRL) secretion to stimulate lactation. Lactotrophs express estrogen receptors (ER) and are a well established estrogen-responsive cell system. 17B-estradiol (E2) is known to directly affect lactotrophs by increasing PRL transcription and biosynthesis, intracellular Ca2+ concentration ([Ca2+]i) and PRL secretion. This study demonstrates that the MMQ clonal cell line, isolated from the 7315a rat pituitary tumor, is a model lactotroph cell line that is E2-responsive. Spontaneous and evoked Ca2+ transients were especially sensitive to L-type channel block, but not affected by block of omega-conotoxin-GVIA-sensitive CaV channels or TTX-sensitive voltage-gated …
Altered Calcium Handling In Cerebellar Purkinje Neurons With The Malignant Hyperthermia Mutation, Ryr1-Y522s/+, George C. Talbott
Altered Calcium Handling In Cerebellar Purkinje Neurons With The Malignant Hyperthermia Mutation, Ryr1-Y522s/+, George C. Talbott
Electronic Theses and Dissertations
To investigate the etiology of malignant hyperthermia and central core disease, mouse models have recently been generated and characterized (Chelu et al., 2006). These RyRY522S/+ knock-in mutant mice provide an excellent tool to investigate calcium dysregulation, its pathological consequences, and potential therapeutic approaches. Skeletal muscle harboring this mutation exhibits calcium leak from internal stores and an increased sensitivity to activation by caffeine, voltage, and temperature (Durham et al., 2008). Although alterations in RyR1 channel function and resultant changes in cellular function have been characterized in skeletal muscle, the effects of MH mutations in RyR1 on central nervous system function have …
The Endocytic Protein Numb Regulates App Metabolism And Notch Signaling: Implications For Alzheimer's Disease, George Kyriazis
The Endocytic Protein Numb Regulates App Metabolism And Notch Signaling: Implications For Alzheimer's Disease, George Kyriazis
Electronic Theses and Dissertations
Increased production of amyloid beta (A-beta) peptide, via altered proteolytic cleavage of amyloid protein precursor (APP), and abnormalities in neuronal calcium homeostasis play central roles in the pathogenesis of Alzheimer's disease (AD). Notch1, a membrane receptor that controls cell fate decisions during development of the nervous system, has been linked to AD because it is a substrate for the gamma-secretase protein complex in which mutations cause early-onset inherited AD. Numb is an evolutionarily conserved endocytic adapter involved in the internalization of transmembrane receptors. Mammals produce four Numb isoforms that differ in two functional domains, a phosphotyrosine-binding domain (PTB) and a …
Lifestyle Intervention Program With Calcium Supplementation To Promote Weight Loss And Body Fat Reduction In Overweight Individuals., Candee Meredith Spence
Lifestyle Intervention Program With Calcium Supplementation To Promote Weight Loss And Body Fat Reduction In Overweight Individuals., Candee Meredith Spence
Electronic Theses and Dissertations
The purpose of this study was to determine if there was a significant difference in weight loss, body fat, waist circumference, or diet quality among participants taking calcium or placebo supplements in a lifestyle intervention program. Three participants ages 52-55 completed the 14 week program. Two participants took 1,000 milligrams calcium while one participant took a placebo. Changes in diet were analyzed by Nutribase IV and self perception. Anthropometrics were analyzed by analysis of variance, alpha level 0.05. There was significant decrease in weight and waist circumference for the calcium group and decrease in bioelectrical impedance for the placebo group; …
Adolescent Girls:Calcium Intake And Sources, Laura Agard
Adolescent Girls:Calcium Intake And Sources, Laura Agard
Electronic Theses and Dissertations
Calcium is an essential nutrient required for normal growth and development of the skeleton and teeth. Adequate calcium intake is critical during early adolescence to optimize peak bone mass and decrease the risk of osteoporosis later in life. Previous researchers, however, have concluded that adolescent girls consume insufficient calcium to meet the demands of rapid skeletal growth. National surveys conducted prior to 1997 showed that t.he major sources of calcium for adolescent girls were milk and milk products. Shortly after the new Dietary Reference Intakes (DRI's) for calcium were released in 1997, calcium fortified foods became more readily available on …
Electrophysiology, Cell Calcium, And Mechanisms Of Hepatocyte Volume Regulation, Walid E. Khalbuss
Electrophysiology, Cell Calcium, And Mechanisms Of Hepatocyte Volume Regulation, Walid E. Khalbuss
Electronic Theses and Dissertations
The electrophysiologic technique (Reuss, L., Proc. Natl. Acad. Sci. USA 82:6014, 1985) was modified to measure changes in steady-state hepatocyte volume during osmotic stress. Hepatocytes in mouse liver slices were loaded with tetramethylammonium ion (TMA$\sp{+}$) during transient exposure of cells to nystatin. Intracellular TMA$\sp{+}$ activity (a$\sp{\rm i}\sb{\rm TMA}$) was measured with TMA$\sp{+}$-sensitive, double-barreled microelectrodes. Loading hepatocytes with TMA$\sp{+}$ did not change their membrane potential (V$\sb{\rm m}$), and under steady-state conditions a$\sp{\rm i}\sb{\rm TMA}$ remained constant over 4 min in single impalements. Hyperosmotic solutions (50, 100, & 150 mM sucrose added to media) and hyposmotic solutions (sucrose in media reduced by …