Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 4 of 4
Full-Text Articles in Life Sciences
Isolation And Characterization Of Temperature-Sensitive Protein Synthesis Mutants Of Escherichia Coli By Directed Mutagenesis Of The Defective Bacteriophage Lambda Fus2, Kenton L. Lohman
Electronic Theses and Dissertations
Mutagenesis of the defective transducing bacteriophage lambda fus2 was used to isolate a collection of temperature-sensitive mutants of E. coli in the major ribosomal protein gene cluster. Four mutants were examined in detail. Two of the mutants were resistant to the ribosomal antibiotics neamine and spectinomycin. Another mutant was defective in 50S ribosomal subunit assembly at 42(DEGREES)C. The 30S subunit proteins S17 and S19 were changed in two different mutants. Each protein migrated as a more basic species in two-dimensional gels of ribosomal proteins. Ribosomes from each of the four mutants examined showed a temperature-dependent reduction in translational activity in …
Cisplatin Ototoxicity In The Guinea Pig: An Electrophysiological, Morphological, And Biochemical Study, Sarah E. Barron
Cisplatin Ototoxicity In The Guinea Pig: An Electrophysiological, Morphological, And Biochemical Study, Sarah E. Barron
Electronic Theses and Dissertations
The purpose of this study was to determine changes induced by cisplatin on hair cell (HC) morphology, compound action potential (CAP), Preyer reflex (PR), and Na,K-ATPase activity in the cochlear lateral wall. Guinea pigs were treated with either 0.42, 0.83, 1.17, 1.50 mg/kg cisplatin, i.p. or sterile water for 12 consecutive days and tested on day 13. HC condition was visualized with scanning electron microscopy (SEM), CAP was initiated with a 1 volt click, and Na,K-ATPase activity was measured by the method of Fiske and SubbaRow. HC damage was linear with dose and occurred throughout the turns of the cochlea …
Failure Of Opioids To Modify Noradrenergic Neuronal Recovery From A Dorsal Bundle Lesion In Neonatal Rats, Ellen L. Kunkel-Bagden
Failure Of Opioids To Modify Noradrenergic Neuronal Recovery From A Dorsal Bundle Lesion In Neonatal Rats, Ellen L. Kunkel-Bagden
Electronic Theses and Dissertations
Morphine and exogenous opioid peptides alter the development of central noradrenergic neurons damaged by neonatal treatment with the neurotoxin 6-hydroxydopa. Transection of the dorsal noradrenergic bundle (DNB) in neonatal rats produces nearly the same alteration in the developmental pattern. It was of interest to determine whether morphine or an exogenous opioid peptide (metenkephalin) was able to modify the recovery of noradrenergic neurons after neonatal surgical transection of the DNB. Neonatal rats were divided into two groups. Both groups received saline (0.85%) or naloxone (2.0 mg/kg) by the intraperitoneal (i.p.) route. In the first group the animals received an additional i.p. …
Human Lung Tryptase Purification And Characterization, Timothy J. Smith
Human Lung Tryptase Purification And Characterization, Timothy J. Smith
Electronic Theses and Dissertations
Human lung tryptase (HLT), a mast cell derived trypsin-like enzyme, was isolated from whole human lung tissue obtained at autopsy. Increased yields from this purification process allowed extensive characterization of the enzyme. One of the critical steps in the purification scheme was the use of a linear heparin gradient to elute active material from cellulose phosphate. Gel filtration studies in 1.0 M NaCl yielded an apparent M(,r) of 135,000, and subsequent electrophoresis on sodium dodecyl sulfate-polyacrylamide gels demonstrated the presence of two active species with apparent M(,r) = 30,900 and 31,600. Enzymatic activity was sensitive to NaCl concentrations above 0.05 …