Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons™

Open Access. Powered by Scholars. Published by Universities.®

Cleveland State University

Series

1998

Articles 1 - 11 of 11

Full-Text Articles in Life Sciences

Phorbol 12-Myristate 13-Acetate Stimulates Lysophosphatidic Acid Secretion From Ovarian And Cervical Cancer Cells But Not From Breast Or Leukemia Cells, Zhongzhou Shen, Jerome Belinson, Richard E. Morton, Yan Xu Dec 1998

Phorbol 12-Myristate 13-Acetate Stimulates Lysophosphatidic Acid Secretion From Ovarian And Cervical Cancer Cells But Not From Breast Or Leukemia Cells, Zhongzhou Shen, Jerome Belinson, Richard E. Morton, Yan Xu

Chemistry Faculty Publications

Lysophosphatidic acid (LPA) is present in ascites from patients with ovarian cancer. It stimulates calcium release and growth of ovarian cancer cells bothin vitroandin vivo.Recently, we found that LPA levels were significantly elevated in plasma from patients with ovarian cancer and other gynecological cancers. In contrast, LPA levels were not elevated in patients with breast cancer and leukemias. In view of this, we investigated whether gynecological cancer cells could produce LPA. LPA was extracted from the supernatant of cells culturedin vitroand purified by thin layer chromatography. After hydrolysis and transmethylation, the fatty acid derivatives were analyzed by gas chromatography. We …

Go to article

Hsp70 And Larval Thermotolerance In Drosophila Melanogaster: How Much Is Enough And When Is More Too Much?, Robert A. Krebs, Martin E. Feder Nov 1998

Hsp70 And Larval Thermotolerance In Drosophila Melanogaster: How Much Is Enough And When Is More Too Much?, Robert A. Krebs, Martin E. Feder

Biological, Geological, and Environmental Faculty Publications

Heat shock proteins (Hsps) and other molecular chaperones perform diverse cellular roles (e.g., inducible thermotolerance) whose functional consequences are concentration dependent. We manipulated Hsp70 concentration quantitatively in intact larvae of Drosophila melanogaster to examine its effect on survival, developmental time and tissue damage after heat shock. Larvae of an extra-copy strain, which has 22 hsp70 copies, produced Hsp70 more rapidly and to higher concentrations than larvae of a control strain, which has the wild-type 10 copies of the gene. Increasing the magnitude and duration of pretreatment increased Hsp70 concentrations, improved tolerance of more severe stress, and reduced delays in development. …

Go to article

1998 Scholars And Artists Bibliography, Michael Schwartz Library, Cleveland State University, Friends Of The Michael Schwartz Library Oct 1998

1998 Scholars And Artists Bibliography, Michael Schwartz Library, Cleveland State University, Friends Of The Michael Schwartz Library

Scholars and Artists Bibliographies

This bibliography was created for the annual Friends of the Michael Schwartz Library Scholars and Artists Reception, recognizing scholarly and creative achievements of Cleveland State University faculty, staff and emeriti

Go to article

Simultaneous Formation Of Functional Leading And Lagging Strand Holoenzyme Complexes On A Small, Defined Dna Substrate, Anthony J. Berdis, Stephen J. Benkovic Sep 1998

Simultaneous Formation Of Functional Leading And Lagging Strand Holoenzyme Complexes On A Small, Defined Dna Substrate, Anthony J. Berdis, Stephen J. Benkovic

Chemistry Faculty Publications

The biochemical characterization of leading and lagging strand DNA synthesis by bacteriophage T4 replication proteins has been addressed utilizing a small, defined primer/template. The ATP hydrolysis activity of 44/62, the clamp loading complex responsible for holoenzyme assembly, was monitored during assembly of both the leading and lagging strand holoenzyme complex. The ATPase activity of 44/62 diminishes once a functional holoenzyme is assembled on both the leading and lagging strand. The assembly of the lagging strand holoenzyme is facilitated by several factors including biotinylated streptavidin blocks at the end of the fork strands, preassembly of the leading strand holoenzyme, and by …

Go to article

Adopting An Ecosystem Approach: Local Variability In Remedial Action Planning, Wendy A. Kellogg Jul 1998

Adopting An Ecosystem Approach: Local Variability In Remedial Action Planning, Wendy A. Kellogg

All Maxine Goodman Levin School of Urban Affairs Publications

Provides information on a study that describes the adoption of an ecosystem approach by lead agencies in two remedial action plans (RAP) for Great Lakes basin. Guidelines on what an ecosystem approach is; Account on International Joint Commission (IJC); Congruency between RAP processes with IJC articulation; How variability in local conditions shaped the innovation adoption process.

Go to article

Heritability Of Expression Of The 70kd Heat-Shock Protein In Drosophila Melanogaster And Its Relevance To The Evolution Of Thermotolerance, Robert A. Krebs, Martin E. Feder, Jeehyun Lee Jun 1998

Heritability Of Expression Of The 70kd Heat-Shock Protein In Drosophila Melanogaster And Its Relevance To The Evolution Of Thermotolerance, Robert A. Krebs, Martin E. Feder, Jeehyun Lee

Biological, Geological, and Environmental Faculty Publications

The principle inducible heat-shock protein of Drosophila melanogasrer, Hsp70, contributes to thermotolerance throughout the entire life cycle of the species but may also reduce fitness in some life stages. In principle, selection might maximize the benefits of Hsp70 expression relative to its costs by adjusting the magnitude of Hsp70 expression for each life-cycle stage independently. Therefore we examined whether the magnitude of Hsp70 ex pre sion varied during the life cycle and the relationship of this variation to several life-history traits. For 28 isofemale lines derived from a single natural population, estimates of heritable variation in Hsp70 expression ranged between …

Go to article

Experimental Manipulation Of The Cost Of Thermal Acclimation In Drosophila Melanogaster, Robert A. Krebs, Martin E. Feder Apr 1998

Experimental Manipulation Of The Cost Of Thermal Acclimation In Drosophila Melanogaster, Robert A. Krebs, Martin E. Feder

Biological, Geological, and Environmental Faculty Publications

Acclimation to environmental change can impose costs on organisms. One potential cost is the energy and nutrients consumed by a physiological response, e.g. the resources required for expression of heat-shock proteins (Hsps). We examined the significance of this cost by genetic manipulation. We isolated four isofemale lines from a Drosophila melanogaster population previously transformed with a hsp70-kcZ fusion. Lines were similar in Hsp70 expression but differed in P-galactosidase expression upon heat shock, and replicates of each line were reared on a high quantity and low quantity medium. Multiple heat shock reduced survival in all lines, but did not increase developmental …

Go to article

Natural And Genetic Engineering Of The Heat-Shock Protein Hsp70 In Drosophila Melanogaster: Consequences For Thermotolerance, Martin E. Feder, Robert A. Krebs Jan 1998

Natural And Genetic Engineering Of The Heat-Shock Protein Hsp70 In Drosophila Melanogaster: Consequences For Thermotolerance, Martin E. Feder, Robert A. Krebs

Biological, Geological, and Environmental Faculty Publications

Larvae of the fruit fly, Drosophila melanogaster, live within necrotic fruit, a challenging environment in which larvae can experience severe thermal stress. One response to thermal stress, the expression of heat-shock proteins (Hsps), has evolved distinctively in this species; the gene encoding Hsp70 has undergone extensive duplication and accounts for the bulk of Hsps that are expressed upon heat shock. Genetic engineering of hsp70 copy number is sufficient to affect thermotolerance at some (but not all) life stages. Increases in Hsp70, moreover, can protect intact larvae against thermal inactivation of the enzyme alcohol dehydrogenase and thermal inhibition of feeding. …

Go to article

Simulation Of Complex Movements Using Artificial Neural Networks, Holk Cruse, Jeffrey Dean, Thomas Kindermann, Josef Schmitz, Michael Schumm Jan 1998

Simulation Of Complex Movements Using Artificial Neural Networks, Holk Cruse, Jeffrey Dean, Thomas Kindermann, Josef Schmitz, Michael Schumm

Biological, Geological, and Environmental Faculty Publications

A simulated network for controlling a six-legged, insect-like walking system is proposed. The network contains internal recurrent connections, but important recurrent connections utilize the loop through the environment. This approach leads to a subnet for controlling the three joints of a leg during its swing which is arguably the simplest possible solution. The task for the stance subnet appears more difficult because the movements of a larger and varying number of joints (9-18: Three for each leg in stance) have to be controlled such that each leg contributes efficiently to support and propulsion and legs do not work at cross …

Go to article

Sequence Profile Of The Parallel Β Helix In The Pectate Lyase Superfamily, Susan Heffron, Gregory R. Moe, Volker Sieber, Jerome Mengaud, Pascale Cossart, Jacqueline Vitali, Frances Jumak Jan 1998

Sequence Profile Of The Parallel Β Helix In The Pectate Lyase Superfamily, Susan Heffron, Gregory R. Moe, Volker Sieber, Jerome Mengaud, Pascale Cossart, Jacqueline Vitali, Frances Jumak

Physics Faculty Publications

The parallel β helix structure found in the pectatelyasesuperfamily has been analyzed in detail. A comparative analysis of known structures has revealed a unique sequenceprofile, with a strong positional preference for specific amino acids oriented toward the interior of the parallel β helix. Using the unique sequenceprofile, search patterns have been constructed and applied to the sequence databases to identify a subset of proteins that are likely to fold into the parallel β helix. Of the 19 families identified, 39% are known to be carbohydrate-binding proteins, and 50% belong to a broad category of proteins with sequences containing leucine-rich repeats …

Go to article

The Three-Dimensional Structure Of Aspergillus Niger Pectin Lyase B At 1.7-Å Resolution1, Jacqueline Vitali, Brian Schick, Harry C.M. Kester, Jaap Visser, Frances Jurnak Jan 1998

The Three-Dimensional Structure Of Aspergillus Niger Pectin Lyase B At 1.7-Å Resolution1, Jacqueline Vitali, Brian Schick, Harry C.M. Kester, Jaap Visser, Frances Jurnak

Physics Faculty Publications

The three-dimensional structure of Aspergillus niger pectin lyase B (PLB) has been determined by crystallographic techniques at a resolution of 1.7 Å. The model, with all 359 amino acids and 339 water molecules, refines to a final crystallographic R factor of 16.5%. The polypeptide backbone folds into a large right-handed cylinder, termed a parallel b helix. Loops of various sizes and conformations protrude from the central helix and probably confer function. The largest loop of 53 residues folds into a small domain consisting of three antiparallel b strands, one turn of an a helix, and one turn of a 310 …

Go to article