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Full-Text Articles in Medicine and Health Sciences

Localization Of Sodium, Potassium-Adenosine Triphosphatase In The Cerebral Cortex Of Developing Rats, Maki Ujiie Sep 1998

Localization Of Sodium, Potassium-Adenosine Triphosphatase In The Cerebral Cortex Of Developing Rats, Maki Ujiie

Loma Linda University Electronic Theses, Dissertations & Projects

Active transport via Na+, K+-ATPase plays an important role in establishing and maintaining proper ionic gradient across all mammalian cell membranes. A strict regulation of Na+, and K+ ion levels is especially important in excitable cells such as neurons and myocytes. Inhibition of the enzyme is associated with several pathological conditions and has serious detrimental effects on cerebral cortical cells. Yet the enzyme appears to be limited in amount and distribution in newborn rats. In this study, Na+, K+- ATPase expression and distribution in early postnatal rats were studied …


In Vitro Assessment Of The Toxicity Of Cocaine And Its Metabolites In The Human Umbilical Artery, Tessa L. Long Aug 1998

In Vitro Assessment Of The Toxicity Of Cocaine And Its Metabolites In The Human Umbilical Artery, Tessa L. Long

Electronic Theses and Dissertations

An in vitro model was used to assess the effect of cocaine and its metabolites on the umbilical artery. Objectives were to pharmacologically confirm the presence of adrenergic innervation using tyramine, evaluate the ability of cocaine, benzoylecgonine, norcocaine and cocaethylene to potentiate vasoconstriction by serotonin and norepinephrine, examine the ability of ketanserin to block the enhanced vasoconstriction produced by cocaine, and determine displacement of 3 H-ketanserin by serotonin, norepinephrine, tyramine and mianserin. The vasoconstrictive effect of tyramine (100 μM) was enhanced in the presence of cocaine by 257%. Vasoconstrictive effects of serotonin and norepinephrine were significantly enhanced by cocaine by …


Expression, Isolation And Purification Of Human Zona Pellucida Protein 3, Ting-Fung Chi Jul 1998

Expression, Isolation And Purification Of Human Zona Pellucida Protein 3, Ting-Fung Chi

Theses and Dissertations in Biomedical Sciences

Mammalian fertilization involves interactions of sperm surface receptors with the ligands of the zona pellucida, an extracellular matrix surrounding the ovulated oocytes. In humans, the zona pellucida is composed of three major glycoproteins. One of them, ZP3, participates in the primary sperm binding and in the subsequent triggering of the spermatozoa's acrosome reaction. Studies on the role of this specific protein in the human fertilization process are hampered by the limited amount of available biologically functional proteins.

By use of a pcDNA 3.1(+) expression vector, a transfecting-vector was constructed containing a 1.3 kb histidine tagged hZP3 cDNA. This histidine tagged …


Leukemia Inhibitory Factor (Lif): Murine Preimplantation Embryo Development, Implantation Rates, And Skeletal Development, Michael Hayes Mitchell Jul 1998

Leukemia Inhibitory Factor (Lif): Murine Preimplantation Embryo Development, Implantation Rates, And Skeletal Development, Michael Hayes Mitchell

Theses and Dissertations in Biomedical Sciences

Leukemia inhibitory factor (LIF) is a pleiotropic cytokine which demonstrates perplexing physiological effects. It has been demonstrated that LIF is essential for implantation in mice. Little is known relating to the manner by which LIF effects pre-implantation and post-implantation development. The objectives of this project were to determine the effects LIF on pre-implantation development, to determine the effects that it may have on implantation rates, successful pregnancy rates, and resorption rates, and to determine the effects that LIF has on the skeletal development of mice. For the embryo transfer experiments, embryos were exposed to test compounds in the transfer medium …


Characterization Of The Biological Functions Of Human Recombinant Zona Pellucida Protein 3, Yu Wen Juan Jul 1998

Characterization Of The Biological Functions Of Human Recombinant Zona Pellucida Protein 3, Yu Wen Juan

Theses and Dissertations in Biomedical Sciences

Recombinant human zona pellucida protein 3 (rhZP3), expressed. isolated and purified from PA-1 cells, is characterized for its biological activity and the role in the signal transduction pathway. Characterization of the biological activity of rhZP3 was detected by hemizona assay and immunofluorescence staining of acrosome reaction The results indicated that rhZP3 exhibited an inhibition in the binding assay (HZI 43.6 +/-3.3; n = 9; 30 ng/mL rhZP3) and induction of acrosome reaction (198.6% +/- 77.2% increase from baseline; n = 29; 30 ng/mL rhZP3). It was further confirmed by the transmission electron microscopy that there was no difference in morphology …


Development Of Fluorescent Techniques In The Kinetic Characterization Of Reverse Transcriptase, Kevin Kevin Howerton Jul 1998

Development Of Fluorescent Techniques In The Kinetic Characterization Of Reverse Transcriptase, Kevin Kevin Howerton

Chemistry & Biochemistry Theses & Dissertations

Reverse transcriptase (RT) is an RNA-directed DNA polymerase isolated from human immunodeficiency virus (HIV) and other retroviruses. It has been the primary target for anti-HIV research since the discovery of its vital role in the retroviral life-cycle. The conventional method for carrying out kinetic characterization and inhibition studies of reverse transcriptase involves the use of radioactive materials. Although this method is effective, it is both time consuming, due to a necessary repeated washing step, and hazardous to the worker and environment. Furthermore, strict laws limit the use of radioactive materials to licensed workers and laboratories. In response to these concerns, …


A Model Using Radiation And Pws4-Htnf-Α Gene Therapy For Treatment Of Glioblastomas, Angelo G. Baher Jun 1998

A Model Using Radiation And Pws4-Htnf-Α Gene Therapy For Treatment Of Glioblastomas, Angelo G. Baher

Loma Linda University Electronic Theses, Dissertations & Projects

The efficacy of radiotherapy for cancer is limited by the dose that can be safely delivered to the tumor without causing debilitating side effects. In addition, successful treatment of highly malignant tumors such as glioblastomas is likely to require adjunctive therapies to enhance tumor response to radiation. Previous studies have shown immunomodulation and a synergestic reduction in tumor volume of malignant tumors when tumor necrosis factor-α (TNF-α) protein is administered prior to radiation. The major goal of the present investigation was to evaluate the efficacy of pWS4-human TNF-α (pWS4-hTNF-α), a new plasmid construct that expresses human TNF-α protein, together with …


Developmental And Hormonal Regulation Of The Expression Of Cytosolic Phospholipase A2 Protein Levels In Baboon Placenta, Kathleen Elizabeth Dunstan Apr 1998

Developmental And Hormonal Regulation Of The Expression Of Cytosolic Phospholipase A2 Protein Levels In Baboon Placenta, Kathleen Elizabeth Dunstan

Chemistry & Biochemistry Theses & Dissertations

Cytosolic phospholipase A2 ( cPLA2) specifically catalyzes the release of arachidonate from membrane phospholipids, thus initiating synthesis of prostaglandins, thromboxanes, and other eicosanoids. The human and nonhuman primate placenta actively synthesize high levels of eicosanoids which play both an autocrine and paracrine role in placental function. Previous studies in Dr. Miriam D. Rosenthal's laboratory have shown that cPLA2 mRNA levels are developmentally regulated. The present study was designed to determine whether placental cPLA2 protein levels increased during gestation. Since the marked increases in estrogen levels during normal pregnancy have been shown to enhance morphological and …


Development Of An Atomic Force Microscopic Immunosensor For The Ferritin Antigen, Brendan O'Connell Jan 1998

Development Of An Atomic Force Microscopic Immunosensor For The Ferritin Antigen, Brendan O'Connell

Theses

The adsorption conditions for a range of different immunoreactants to both polystyrene and ultrasmooth silanised silicon surfaces are optimised. The conditions studied were concentration of protein, time and temperature of incubation, pH, molarity and ionic strength of the buffer. The anti-ferritin surface was selected as our model system. This immunosensor was used to develop and evaluate a millispot ELISA for ferritin. The millispot ferritin ELISA developed utilises a sample volume of 6pl and a sample incubation time of 10 minutes. Precision and accuracy studies show the assay to have a dynamic assay range of 7.8-lOOng/ml ferritin. The millispot ELISA detected …


Evaluation Of The Role Of Fructosamine As An Indicator Of Diabetic Control, Katherine Hooley Jan 1998

Evaluation Of The Role Of Fructosamine As An Indicator Of Diabetic Control, Katherine Hooley

Theses

Diabetes mellitus, a common metabolic disease, is characterised by excess circulating glucose concentrations. Such a hyperglycaemic status provides the stimulus for irreversible glycation (non-enzymatically post-translational) of structural and functional proteins. Protein glycation, although a cause of complication (neuropathy, micro/macrovascular disease), provides a time-averaged index of diabetes status and control. In particular, glycated plasma proteins analysis, i.e., the fructosamine assay, has received favourable response due to its speed, simplicity, low cost, and ease of automation. However, lack of standardisation and a universally-accepted calibrant has limited technical and subsequent clinical confidence in fructosamine analysis. In response, a comprehensive technical evaluation (including novel …


Development Of A Differential Assay To Selectively Measure Α-Amylase Isoenzymes., Miriam O'Connor Jan 1998

Development Of A Differential Assay To Selectively Measure Α-Amylase Isoenzymes., Miriam O'Connor

Theses

α-Amylase is a heterogeneous polypeptide, primarily found in the Salivary and Pancreatic glands, giving rise to two isoenzymes, namely Salivary- and Pancreatic-type Amylases. Total α-Amylase activity measurements are routinely carried out in hospital laboratories to aid in the diagnosis of diseases of the pancreas and in the investigation of pancreatic function in patients with severe abdominal pains. With the development and wide availability of modem chromogenic oligosaccharide substrates specific for Amylase, assays have become more sensitive, rapid and easier to use.

Differential Amylase Isoenzyme assays ware developed to distinguish isoenzyme levels. Several methods were developed for isoenzyme determination. Of these. …


Development And Validation Of An Improved Ultrasensitive Assay For Cardiac Troponin I (Ctni), William G. Blake Jan 1998

Development And Validation Of An Improved Ultrasensitive Assay For Cardiac Troponin I (Ctni), William G. Blake

Theses

Cardiac troponin I (cTnl) has been reported to be a highly specific marker for myocardial injury. In patients suffering from acute coronary syndromes, a sensitive serum marker which is closely related to the extent of myocardial damage which provides prognostic data and which can be measured rapidly is desirable. In this thesis a “sandwich” enzyme immunoassay was developed to measure cTnI. The developed assay was reproducible with the inter assay precision ranging from 4.8-14% and the intra assay precision ranging from 3.1-9.5%. The limit of detection of the assay was calculated as 0.385 ng/ml. The upper reference range (non-parametric 95% …


Development And Validation Of Flow-Injection (Continuous-Flow) Elisa Techniques., Declan Gerard Spillane Jan 1998

Development And Validation Of Flow-Injection (Continuous-Flow) Elisa Techniques., Declan Gerard Spillane

Theses

A flow-through enzyme-linked immunosorbent assay was developed based on affinity chromatography using the determination of ferritin in serum as a model system. In this method, samples and standards are introduced to separate columns containing immobilised anti-ferritin antibody, and antigen bound by solid-phase antibody is subsequently detected using an anti-ferritin-alkaline phosphatase conjugate. To detect immobilised label, p-nitrophenyl phosphate is added and product is developed in the column at room temperature. Following elution of product from the column, the absorbance is measured and the columns are regenerated using a low pH elution. The final developed system requires approximately 1.5 h for the …


Development Of An Elisa Method For The Measurement Of Cd44 Expression In Human Serum, Ciara Hurley Jan 1998

Development Of An Elisa Method For The Measurement Of Cd44 Expression In Human Serum, Ciara Hurley

Theses

CD44 is a cell surface glycoprotein (mol. wt. =85-95 kDa) which has been implicated in lymphocyte-HEV interactions and the process of lymphocyte homing. CD44 is a complex glycoprotein which undergoes extensive alternative splicing to generate various CD44 isoforms. CD44 functions include the delivery of an activation signal to T-cells, binding to hyaluronate, mediation of lymphocyte homing, and the spread of metastatic cells. CD44 has been particularly implicated in the dissemination of non- Hodgkin's lymphoma and as such may serve as a useful prognostic marker of disease progression. CD44 measurement in serum may provide a rapid, inexpensive and relatively non-invasive prognostic …