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Full-Text Articles in Life Sciences

Reinvigorating Introductory Biology: A Theme-Based, Investigative Approach To Teaching Biology Majors, Cynthia Norton, Lynne H. Gildensoph, Martha Phillips, Deborah Wygal, Kurt Olson, John Pellegrini, Kathleen Tweeten Oct 1997

Reinvigorating Introductory Biology: A Theme-Based, Investigative Approach To Teaching Biology Majors, Cynthia Norton, Lynne H. Gildensoph, Martha Phillips, Deborah Wygal, Kurt Olson, John Pellegrini, Kathleen Tweeten

Kurt Olson

No abstract provided.


Spiroplasma Lineolae Sp. Nov., From The Horsefly Tabanus Lineola (Diptera : Tabanidae), Frank E. French, Robert F. Whitcomb, Joseph G. Tully, Patricia Carle, Joseph M. Bové, Roberta B. Henegar, Jean R. Adams, Gail E. Gasparich, David L. Williamson Sep 1997

Spiroplasma Lineolae Sp. Nov., From The Horsefly Tabanus Lineola (Diptera : Tabanidae), Frank E. French, Robert F. Whitcomb, Joseph G. Tully, Patricia Carle, Joseph M. Bové, Roberta B. Henegar, Jean R. Adams, Gail E. Gasparich, David L. Williamson

Gail Gasparich

Spiroplasma strain TALS-2T from the viscera of the striped horsefly, Tabanus lineola, collected in Georgia was serologically distinct from other Spiroplasma species, groups, putative groups, and subgroups. Light and electron microscopy of cells of strain TALS-2T revealed helical motile cells surrounded only by a single cytoplasmic membrane. The organism grew in M1D and SP-4 liquid media. Growth also occurred in 1% serum fraction medium and in conventional horse serum medium. Growth in liquid media was serum dependent. The strain passed through 220-nm filter pores, but was retained in filters with 100-nm pores. The optimum temperature for growth was 30°C. Multiplication …


Collaborative Roles For C-Jun N-Terminal Kinase, C-Jun, Serum Response Factor, And Sp1 In Calcium-Regulated Myocardial Gene Expression, Patrick M. Mcdonough, Deanna S. Hanford, Amy B. Sprenkle, Noel R. Mellon, Christopher C. Glembotski Sep 1997

Collaborative Roles For C-Jun N-Terminal Kinase, C-Jun, Serum Response Factor, And Sp1 In Calcium-Regulated Myocardial Gene Expression, Patrick M. Mcdonough, Deanna S. Hanford, Amy B. Sprenkle, Noel R. Mellon, Christopher C. Glembotski

Amy Sprenkle

Electrical stimulation of contractions (pacing) of primary neonatal rat ventricular myocytes increases intracellular calcium and activates a hypertrophic growth program that includes expression of the cardiac-specific gene, atrial natriuretic factor (ANF). To investigate the mechanism whereby pacing increases ANF, pacing was tested for its ability to regulate mitogen-activated protein kinase family members, ANF promoter activity, and the trans-activation domain of the transcription factor, Sp1. Pacing and the calcium channel agonist BAYK 8644 activated c-Jun N-terminal kinase (JNK) but not extracellular signal-regulated kinase. Pacing stimulated ANF-promoter activity approximately 10-fold. Furthermore, transfection with an expression vector for c-Jun, a substrate for JNK, …


Ms2 Coat Protein Mutants Which Bind Qβ Rna, Marc Spingola, David S. Peabody Jul 1997

Ms2 Coat Protein Mutants Which Bind Qβ Rna, Marc Spingola, David S. Peabody

Marc Spingola

The coat proteins of the RNA phages MS2 and Qβ are structurally homologous, yet they specifically bind different RNA structures. In an effort to identify the basis of RNA binding specificity we sought to isolate mutants that convert MS2 coat protein to the RNA binding specificity of Qβ. A library of mutations was created which selectively substitutes amino acids within the RNA binding site. Genetic selection for the ability to repress translation from the Qβ translational operator led to the isolation of several MS2 mutants that acquired binding activity for Qβ RNA. Some of these also had reduced abilities to …


Genes That Guide Growth Cones Along The C. Elegans Ventral Nerve Cord, Bruce Wightman, Renee Baran, Gian Garriga Jun 1997

Genes That Guide Growth Cones Along The C. Elegans Ventral Nerve Cord, Bruce Wightman, Renee Baran, Gian Garriga

Renee Baran

During nervous system development, growth cone pioneering and fasciculation contribute to nerve bundle structure. Pioneer growth cones initially navigate along neuroglia to establish an axon scaffold that guides later extending growth cones. In C. elegans, the growth cone of the PVPR neuron pioneers the left ventral nerve cord bundle, providing a path for the embryonic extensions of the PVQL and AVKR growth cones. Later during larval development, the HSNL growth cone follows cues in the left ventral nerve cord bundle provided by the PVPR and PVQL axons. Here we show that mutations in the genes enu-1, fax-1, unc-3, unc-30, unc-42 …


Spiroplasma Chrysopicola Sp. Nov., Spiroplasma Gladiatoris Sp. Nov., Spiroplasma Helicoides Sp. Nov., And Spiroplasma Tabanidicola Sp. Nov., From Tabanid (Diptera: Tabanidae) Flies, Robert F. Whitcomb, Frank E. French, Joseph G. Tully, Gail E. Gasparich, David L. Rose, Patricia Carle, Joseph M. Bove, Roberta B. Henegar, Meghnad Konai, Kevin J. Hackett, Jean R. Adams, Truman B. Clark, David L. Williamson Jun 1997

Spiroplasma Chrysopicola Sp. Nov., Spiroplasma Gladiatoris Sp. Nov., Spiroplasma Helicoides Sp. Nov., And Spiroplasma Tabanidicola Sp. Nov., From Tabanid (Diptera: Tabanidae) Flies, Robert F. Whitcomb, Frank E. French, Joseph G. Tully, Gail E. Gasparich, David L. Rose, Patricia Carle, Joseph M. Bove, Roberta B. Henegar, Meghnad Konai, Kevin J. Hackett, Jean R. Adams, Truman B. Clark, David L. Williamson

Gail Gasparich

Four spiroplasma strains, DF-1T, TG-1T, TABS-2T, and TAUS-1T, all of which were isolated from deerflies or horseflies (Diptera: Tabanidae), were serologically distinct from previously described spiroplasma species, groups, and subgroups. Strain DF-1Toriginated from a Maryland deerfly (Chrysops sp.); strain TG-1Twas isolated from a Maryland horsefly (Tabanus gladiator); strain TAUS-1Toriginated from a member of the Tabanus abdominalis-limbatinevris complex of horseflies collected in Maryland; and strain TABS-2Twas isolated from a horsefly (Tabanus abactor) collected in Oklahoma. Cells of all of the strains appeared to be helical and motile when they were examined by dark-field microscopy. Cells of strain DF-1Tgrowing in M1D medium …


Diet Of Nestling Laughing Gulls In Southern New Jersey, Jerald Dosch Dec 1996

Diet Of Nestling Laughing Gulls In Southern New Jersey, Jerald Dosch

Jerald Dosch, PhD

No abstract provided.


Root-Soil Contact For The Desert Succulent Agave Deserti Engelm. In Wet And Drying Soil, Gretchen North, P. Nobel Dec 1996

Root-Soil Contact For The Desert Succulent Agave Deserti Engelm. In Wet And Drying Soil, Gretchen North, P. Nobel

Gretchen North

To investigate the extent and size of root-soil air gaps that develop during soil drying, resin casts of roots of the desert succulent Agave deserti Engelm. were made in situ for container-grown plants and in the field. Plants that were droughted in containers for 7 and 14 d had 24 and 34% root shrinkage, respectively, leading to root-soil air gaps that would reduce the hydraulic conductivity at the root-soil interface by a factor of about 5. When containers were vibrated during drought, root-soil air gaps were greatly diminished, and the predicted conductivity at the interface was similar to that of …


Salt Tolerance Of Nestling Laughing Gulls: An Experimental Field Investigation, Jerald Dosch Dec 1996

Salt Tolerance Of Nestling Laughing Gulls: An Experimental Field Investigation, Jerald Dosch

Jerald Dosch, PhD

No abstract provided.


Evolutionary Ecology Across Three Trophic Levels: Goldenrods, Gallmakers, And Natural Enemies, Warren Abrahamson, A. Weis Dec 1996

Evolutionary Ecology Across Three Trophic Levels: Goldenrods, Gallmakers, And Natural Enemies, Warren Abrahamson, A. Weis

Warren G. Abrahamson, II

No abstract provided.


The Pax-5 Gene Is Alternatively Spliced During B-Cell Development, Patty Zwollo, Hector Arrieta, Kaleo Ede, Karen Molinder, Stephen Desiderio, Roberta Pollock Dec 1996

The Pax-5 Gene Is Alternatively Spliced During B-Cell Development, Patty Zwollo, Hector Arrieta, Kaleo Ede, Karen Molinder, Stephen Desiderio, Roberta Pollock

Roberta Pollock

The transcription factor Pax-5 is expressed during the early stages of B-cell differentiation and influences the expression of several B-cell-specific genes. In addition to the existing isoform (Pax-5, which we have named Pax-5a), we have isolated three new isoforms, Pax-5b, Pax-5d, and Pax-5e, from murine spleen and B-lymphoid cell lines using library screenings and polymerase chain reaction amplification. Isoforms Pax-5b and Pax-5e have spliced out their second exon, resulting in proteins with only a partial DNA-binding domain. Isoforms Pax-5d and Pax-5e have deleted the 3′-region, which encodes the transactivating domain, and replaced it with a novel sequence. The existence of …


Transplantation Of Fetal Neocortex Ameliorates Sensorimotor And Locomotor Deficits Following Neonatal Ischemic-Hypoxic Brain Injury In Rats, Elizabeth Jansen, Leah Solberg, Suzanne Underhill, Sarah Wilson, Constantino Cozzari, Boyd Hartman, Patricia Faris, Walter Low Dec 1996

Transplantation Of Fetal Neocortex Ameliorates Sensorimotor And Locomotor Deficits Following Neonatal Ischemic-Hypoxic Brain Injury In Rats, Elizabeth Jansen, Leah Solberg, Suzanne Underhill, Sarah Wilson, Constantino Cozzari, Boyd Hartman, Patricia Faris, Walter Low

Elizabeth Jansen

No abstract provided.


Anpassung - Kernpunkt Oder Mißverständnis Der Evolutionstheorie? [Adaptation - Essential Concept Or Misconception Of Evolutionary Biology?], Dieter Stefan Peters, Winfried Peters Dec 1996

Anpassung - Kernpunkt Oder Mißverständnis Der Evolutionstheorie? [Adaptation - Essential Concept Or Misconception Of Evolutionary Biology?], Dieter Stefan Peters, Winfried Peters

Winfried S. Peters

Die Grundzüge des Gesagten lassen sich folgendermaßen zusammenfassen:
- Die Organismen sind in der Evolution keine Objekte, sondern weitgehend autonome Subjekte. Die evolutive Transformation ihrer Konstruktion erfolgt nach Maßgabe ihrer jeweils bereits vorhandenen Strukturen.
- In Abhängigkeit von ihren jeweiligen konstruktiven Möglichkeiten wandern Organismen in Lebensräume ein und schaffen sich ihre Nischen. Was und wie eine ökologische Nische ist, bestimmt sich dabei vom Organismus her. Die Annahme, daß im Selektionsprozeß die Umwelt die Organismen sich anverwandelt, ist theoretisch unnötig, faktisch zweifelhaft, und darüberhinaus entgegen verbreiteter Ansicht von äußerst beschränktem Wert für die phylogenetische Forschungspraxis.
- Die Umwelt taugt nicht zur …


Concerns And Priorities In Genetic Studies: Insights From Recent African American Biohistory, Fatimah Linda Collier Jackson Dec 1996

Concerns And Priorities In Genetic Studies: Insights From Recent African American Biohistory, Fatimah Linda Collier Jackson

Fatimah Linda Collier Jackson

No abstract provided.


Effect Of Genome-Plastome Interaction On Meiosis And Pollen Development In Oenothera Species And Hybrids, Michael J. Chapman, David L. Mulcahy Dec 1996

Effect Of Genome-Plastome Interaction On Meiosis And Pollen Development In Oenothera Species And Hybrids, Michael J. Chapman, David L. Mulcahy

David L. Mulcahy

Oenothera villaricae Dietrich and Oe. picensis Dietrich, complete translocation heterozygotes, are fully interfertile, giving rise to six discrete classes of true­ breeding hybrids from a reciprocal cross. Associated with each parent and hybrid is a characteristic ab01tive non­ staining pollen fraction easily distinguished from fully developed pollen under the light microscope. Pollen abortion has been associated with translocation rings in other angiosperm species, and may characterize such sys­ tems. The abortive pollen fraction is significantly differ­ ent between reciprocal Oenothera hybrids, however (P<0.001), indicative of partial cytoplasmic control. Pol­ len abortion is most severe in the F 1 hybrid …


Factors Influencing Maternal Behaviour In A Burrower Bug, Sehirus Cinctus (Heteroptera: Cydnidae), Scott Kight Dec 1996

Factors Influencing Maternal Behaviour In A Burrower Bug, Sehirus Cinctus (Heteroptera: Cydnidae), Scott Kight

Scott Kight

Female burrower bugs, Sehirus cinctus (Cydnidae), brood and provision their young. This study provides an integrative approach to insect parental behaviour by examining the influence of maternal experience on the maintenance and termination of maternal care. Intensity of care (maternal responsivity) was determined by assaying a subject’s response to tactile disturbance and by measuring time spent in proximity to young. First-brood mothers were highly responsive until 3 days after their eggs hatched. Second-brood mothers, however, were only responsive until 1–2 days post-hatching. This effect was associated with differences in age and parity, but not experience, because …


The Spiroplasma Motility Inhibition Test, A New Method For Determining Intraspecific Variation Among Colorado Potato Beetle Spiroplasmas, Kevin J. Hackett, J. J. Lipa, G. E. Gasparich, D. E. Lynn, M. Konai, M. Camp, R. F. Whitcomb Dec 1996

The Spiroplasma Motility Inhibition Test, A New Method For Determining Intraspecific Variation Among Colorado Potato Beetle Spiroplasmas, Kevin J. Hackett, J. J. Lipa, G. E. Gasparich, D. E. Lynn, M. Konai, M. Camp, R. F. Whitcomb

Gail Gasparich

The Colorado potato beetle, Leptinotarsa decemlineata, is a major holarctic pest of solanaceous crops. Presumably, this insect spread from Solanum species in central America to the Mexican plateau, and this was followed by multiple invasions of North America and Europe. Attempts are being made to control this beetle by using a genetically modified spiroplasma that occurs naturally in its gut. In the current study, spiroplasmas isolated from beetles collected in North America and Poland exhibited serologic (spiroplasma motility inhibition test) and genomic (restriction fragment length polymorphism) profiles that suggest that there were multiple spiroplasma introductions. Two serovars were identified; one …