Life Sciences Commons^™

Predicting The Growth Of Salmonella Typhimurium On Beef By Using The Temperature Function Integration Technique, James S. Dickson, G. R. Siragusa, J. E. Wray Jr.

James S. Dickson

Lag and generation times for the growth of Salmonella typhimurium on sterile lean beef were modeled as functions of cooling time under various carcass-chilling scenarios. Gompertz growth models were fit to the log10 colony counts over time at each of six temperatures in the range of 15 to 40 degrees C. Lag and generation times were defined as the points at which the second and first derivatives, respectively, of each growth curve attained a maximum. Generation time and lag time parameters were modeled as functions of temperature by use of exponential-decay models. The models were applied to typical beef carcass-cooling …

Changes In Intracellular Chloride During Osmotic Stress And L-Alanine Uptake In Mouse Hepatocytes, Kening Wang

Electronic Theses and Dissertations

A stable intracellular ionic environment is necessary for hepatocytes to function normally. Thus, during hypotonic shock or L-alanine uptake, hepatocytes swell and then exhibit a regulatory volume decrease (RVD), which comprises an increase in K$\sp+$ conductance (G$\sb{\rm K}$), an increased K$\sp+$ efflux, and a hyperpolarization of transmembrane potential (V$\sb{\rm m}$). Since hepatocyte intracellular Cl$\sp-$ has been demonstrated to distribute passively with V$\sb{\rm m}$, this study is designed to test the hypothesis that the hypotonic shock- or L-alanine uptake-induced hyperpolarization of V$\sb{\rm m}$ might provide an electromotive force for the efflux of hepatocyte intracellular Cl$\sp-$, which in turn would contribute osmotically …

Retention Of Cellular Viability And Growth Potential In Cryopreserved Bovine Arterial Tissue: Implications For Clinical Use Of Cryopreserved Vascular Allografts, Kip G. Gardner

Biological Sciences Theses & Dissertations

Segments of bovine calf aortas and pulmonary arteries were cryopreserved at -196° C for two weeks to 18 months and subsequently thawed. Cellular morphology, viability, and growth potential in these segments were then compared with the same attributes in segments from fresh (control) arteries. Scanning electron microscopy revealed no disruption of intimal surfaces attributable to cryopreservation. Endothelial cells were successfully cultured from all cryopreserved arterial segments. Endothelial monolayers grown from cryopreserved arteries had a cobblestone appearance and expressed Factor VIII antigen but not smooth muscle alpha-actin. Plating efficiency in primary cultures of endothelial cells was lower for cryopreserved arteries than …

Die Konsequenzen Eines Lebens Im Druckbehälter. Biotheoretische Implikationen Der Organisation Pflanzlicher Organismen [The Consequences Of Living In A Pressure Pot. Biotheoretical Implications Of The Organismic Architecture Of Plants], Winfried Peters, Hubert Felle

Winfried S. Peters

Old Remedies In The Biotechnology Age: Moore V. Regents, Michelle J. Burke, Victoria M. Schmidt

RISK: Health, Safety & Environment (1990-2002)

The California Supreme Court, by excluding a potential remedy, has eliminated many concerns generated by a lower court decision resolving rights to the cell line derived from John Moore's spleen. Yet, the Supreme Court gave little attention to remedies that remain. The authors argue that a constructive trust, a remedy of considerable vintage and great flexibility, could be applied to achieve a just result in such circumstances without affecting the biotechnology world at large.

Molecular And Cellular Analysis Of Chlamydia Trachomatis: Persistence And Reactivation, Kimberly R. Tau

Electronic Theses and Dissertations

Chlamydia trachomatis (CT) is the most prevalent sexually-transmitted infection in the United States. It has been suggested that CT infections can become latent. This has not been substantiated. CT persistence was examined at the molecular and cellular level in vitro and in vivo. Penicillin treatment of CT in vitro results in abnormal inclusions and reduced recovery of infectious CT. Penicillin did not inhibit initial stages of infection, but did downregulate CT rRNA levels after 25 hours post-inoculation (p.i.). DNA amplification was employed to differentiate between a resolved infection and a persistent one. Utilizing a primer pair that amplified a 144 …

Characterization Of A Novel Prostate Tumor-Associated Antigen, Grayson B. Lipford

Theses and Dissertations in Biomedical Sciences

The murine monoclonal antibodies (MAb) TURP-27 and HNK-1 have been shown to detect antigens that are heavily expressed by benign prostatic hyperplasia (BPH) and carcinoma of the prostate (CaP). Western blot analysis of prostate extracts, showed that MAb TURP-27 and MAb HNK-1 bound glycoproteins of 180, 140, 120, 100, 90 and 69 kDa. Studies have shown that the HNK-1 carbohydrate epitope may be involved in cell adhesion and that it is a component of several characterized adhesion proteins. TURP-27 was found to bind at least three of these adhesion proteins: neural cell adhesion molecules (N-CAM), myelin-associated glycoprotein (MAG) and a …

The Growth And Bioenergetics Of Callinectes Sapidus Larvae And The Effects Of Diet Quality On Larval Physiology, James J. Pletl

OES Theses and Dissertations

Food quality, especially ω3 polyunsaturated fatty acids (PUFA), can affect the physiology and metabolic efficiency of larvae of the blue crab, Callinectes sapidus. These affects may correlate with success in development and juvenile recruitment.

Larvae were exposed to two diets differing quantitatively in ω3 PUFA and respiration, excretion, growth, and feeding rates were measured for each larval stage and the megalopal stage. The energy partitioned to molts and specific dynamic action was also measured. T

he ω3 PUFA enriched diet resulted in a lower respiration rate when compared to the unsupplemented diet, but there was little differences in excretion …

Development And Regulation Of Estrogen Receptors In The Neonatal Rat Hippocampus, Joan A. O'Keefe

Dissertations

No abstract provided.

Amino Acids And Pineal Gland Function In The Rat, Laura Kus

Dissertations

No abstract provided.

The Cγ Subunit Is A Unique Isozyme Of The Camp-Dependent Protein Kinase, Stephen J. Beebe, Paul Salomonsky, Tore Jahnsen, Yixin Li

Bioelectrics Publications

There are at least three isozymes (Cα, Cβ, and Cγ) of the mammalian catalytic (C) subunit of cAMP-dependent protein kinase (PKA) (Beebe, S., Oyen, O., Sandberg, M., Froysa, A., Hansson, V., and Jahnsen, T. (1990) Mol. Endocrinol. 4, 465-475). To compare the Cγ and Cα isozymes, the respective cDNAs were expressed in permanently transformed Kin-8 PKA-deficient Y1 adrenal cells using the mouse metallothionein promoter. The recombinant C subunits were characterized as immunoreactive, zinc-inducible, cAMP-dependent kinase activities. In contrast to Cα, histone was a better substrate than Leu-Arg-Arg-Ala-Ser-Leu-Gly (Kemptide) for Cγ. Furthermore, Cγ histone kinase activity was not inhibited by the …

Altered Expression Of Adenovirus 12 Dna-Binding Protein But Not Dna Polymerase During Abortive Infection Of Hamster Cells, Lynne A. Lucher, Benjawan Khuntirat, Jiansheng Zhao, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Replication of human adenovirus type 12 DNA is blocked in abortively infected baby hamster kidney cells. The activity and accumulation of adenovirus 12 DNA polymerase is equivalent in infected hamster and human cell extracts. However, the accumulation of adenovirus type 12 DNA-binding protein is approximately 120-fold lower in extracts from infected hamster cells when compared to infected permissive human cells. This difference in accumulation is not because of replication of viral DNA during productive infection, since this difference is observed in the presence of hydroxyurea. The DNA-binding protein from infected hamster cells retains the ability to bind denatured DNA-cellulose. An …

Magnesium Regulation Of Calcium In Essential Hypertension, Elaine Pringle Gordon

Theses and Dissertations in Biomedical Sciences

Essential hypertension is a complex disease which is treated by palliative methods, since the causal factors are as yet unknown. A variety of both genetic and environmental factors probably combine to produce chronic high blood pressure. A genetic model of essential hypertension, spontaneously hypertensive rats (SHR), and its control strain Wistar Kyoto (WKY) were used to investigate a possible environmental causal factor, cellular magnesium deficit, and its impact on the functional ability of the calcium ATPase. Rats were fed either a magnesium-deficient or a magnesium-sufficient diet for 10 weeks, after which the calcium ATPase activity was measured in intact red …

Auxin-Induced H+-Pump Stimulation Does Not Depend On The Presence Of Epidermal Cells In Corn Coleoptiles, Winfried Peters, Ursula Richter, Hubert Felle

Winfried S. Peters