Biology Commons^™

Contrasts In Tick Innate Immune Responses To Borrelia Burgdorferi Challenge: Immuno-Tolerance In Ixodes Scapularis Versus Immunocompetence In Dermacentor Variabilis (Acari: Ixodidae)., Robert Johns, Jun Ohnishi, Anne Broadwater, Daniel E. Sonenshine, Aravinda M. Desilva, Wayne L. Hynes

Biological Sciences Faculty Publications

The blacklegged tick, Ixodes scapularis Say, transmits the Lyme disease spirochete (Borrelia burgdorferi), whereas the American dog tick, Dermacentor variabilis (Say), is unable to transmit the bacterium. We compared the innate immune response of these ticks against spirochetes directly inoculated into the hemocoel cavity of ticks. In I. scapularis, some Borrelia were found associated with hemocytes, while numerous other spiral-shaped, intact bacteria remained free in the hemolymph. In contrast, in D. variabilis only remnants of the bacteria were evident in the hemolymph, indicating lysis; intact spirochetes were rare. Spirochetes were observed bound to or within the organs …

Factors Mediating Cheatgrass Invasion Of Intact Salt Desert Shrubland, Susan E. Meyer, Susan Garvin, Julie Beckstead

Biology Faculty Scholarship

Cheatgrass (Bromus tectorum) has recently displaced salt desert shrubland in many areas of the Great Basin. We studied the dynamics of cheatgrass invasion into an intact shadscale-gray molly community in Dugway Valley, Utah, by adding seeds and manipulating disturbance regime and resource availability. Shrub clipping or cryptobiotic crust trampling on large plots increased cheatgrass recruitment and biomass production slightly in a favorable moisture year (1997 to 1998), whereas in a less favorable moisture year (1998 to 1999) these disturbance treatments had a significant negative effect. In 1998 to 1999 small plot studies, recruitment was similar in intact shrub clumps and …

Protransglutaminase (Factor Xiii) Mediated Crosslinking Of Fibrinogen And Fibrin, Kevin R. Siebenlist, David A. Meh, Michael W. Mosesson

Biological Sciences Faculty Research and Publications

No abstract provided.

Invasion Of Mouse Fibroblasts And Macrophages By Human Isolates Of Agrobacterium, Karmon Leigh Kriechbaum

Honors Theses

In the past few decades there has been growing evidence that species of Agrobacterium can be opportunistic animal pathogens. One of these species is Agrobacterium tumefaciens, which for years has been studied as a plant pathogen. The results of one published experiment suggested that an Agrobacterium toxin could kill mice (12). Other strong evidence for Agrobacterium as an opportunistic human pathogen is the over fifty published clinical cases in which humans were infected by Agrobacterium species (3, 13-25). In almost all of these cases the patient was immunocompromised in some way and they often had an invasive procedure such as …

Aquaporin 5-Deficient Mouse Lungs Are Hyperresponsive To Cholinergic Stimulation, Carissa M. Krane, Christopher N. Fortner, Arthur R. Hand, Dennis W. Mcgraw, John N. Lorenz, Susan E. Wert, Jennifer E. Towne, Richard J. Paul, Jeffrey A. Whitsett, Anil G. Menon

Biology Faculty Publications

Although aquaporin 5 (AQP5) is the major water channel expressed in alveolar type I cells in the lung, its actual role in the lung is a matter of considerable speculation. By using immunohistochemical staining, we show that AQP5 expression in mouse lung is not restricted to type I cells, but is also detected in alveolar type II cells, and in tracheal and bronchial epithelium. Aqp5 knockout (Aqp5−/−) mice were used to analyze AQP5 function in pulmonary physiology. Compared with Aqp5+/+ mice, Aqp5−/− mice show a significantly increased concentration-dependent bronchoconstriction to intravenously administered Ach, as shown by …

Computer Aided Learning Environment For Biology, Pek Hin Foong

Student Works (2000-2009)

Traditional learning on biology requires of memory rather than understanding. As better educational technology emerges, we are able to utilise the computer as an important tool in learning. Many educational and pedagogical issues, particularly in the field or Artificial intelligence are looked at to help consider a good design for a computer learning tool. Existing computer aided learning materials are also studied to pinpoint their better features and incorporate them into the learning tool. A learning tool is proposed for effective learning in relating facts, rules, text and graphics. This system will have a Study Section containing notes that incorporates …

Hawaiian Freshwater Polychaeta: A Potentially Substantial Trophic Component Of Stream Depositional Habitats, M. Eric Benbow, Albert J. Burky, Carl M. Way

Biology Faculty Publications

In this paper we report the widespread occurrence of large annelids (Polychaeta: Nereididae) in Hawaiian stream depositional habitats, drawing attention to the lack of knowledge of Hawaiian stream energetics. Specimens of Namalycastis sp. were collected from five Hawaiian Islands from May–July 1995 and from the island of Maui from July–December 1999 and April–July 2000. Most specimens collected were N. hawaiiensis, while two specimens of N. abiuma were collected from a single site on the island of Molokai. Specimens were collected from elevations ranging from 3–240 m; several collections were from sites above at least one major (> 15 m …

Genes, Categories, And Species: The Evolutionary And Cognitive Causes Of The Species Problem, Michael Dietrich

Dartmouth Scholarship

Review of Genes, Categories, and Species: The Evolutionary and Cognitive Causes of the Species Problem by Jody Hey.

Firefly Flashing Is Controlled By Gating Oxygen To Light-Emitting Cells, G. S. Timmins, F. J. Robb, C. M. Wilmot, S. K. Jackson, H. M. Swartz

Dartmouth Scholarship

Although many aspects of firefly bioluminescence are understood, the mechanism by which adult fireflies produce light as discrete rapid flashes is not. Here we examine the most postulated theory, that flashing is controlled by gating oxygen access to the light-emitting cells (photocytes). According to this theory, the dark state represents repression of bioluminescence by limiting oxygen, which is required for bioluminescence; relief from this repression by transiently allowing oxygen access to the photocytes allows the flash. We show that normobaric hyperoxia releases the repression of light emission in the dark state of both spontaneously flashing and non-flashing fireflies, causing continual …

Return To The Cumaca Cave, Trinidad, W.I, Aldemaro Romero Jr., Anuradha Singh, Annabelle Mckie, Michael Manna, Ruth Baker, Kelly M. Paulson

Publications and Research

No abstract provided.

Developmental Tendril Morphology In Echinocystis Lobata (Michaux) Torrey And Gray (Cucurbitaceae), Theodore Bowen Guthrie

Dissertations and Theses @ UNI

Tendrils are generally defined as coiling organs used as mechanical supports and for climbing. The morphological nature of the tendril and the branching pattern of the axillary bud complex (ABC) in the family Cucurbitaceae have been the subject of investigation for over a hundred years and as of yet there is no unifying interpretation of their morphological values. The tendril in the Cucurbitaceae has been hypothesized to be homologous to a leaf, a flower, a stem, and a combination of stem and leaf. Echinocystis lobata (Michaux) Torrey and Gray was used as a model to study the ontogeny of the …

Acclimation To Hypoxia Increases Survival Time Of Zebrafish, Danio Rerio, During Lethal Hypoxia, Bernard B. Rees, F Sudradjat, J W. Love

Biological Sciences Faculty Publications

Survivorship of zebrafish, Danio rerio, was measured during lethal hypoxic stress after pretreatment in water at either ambient oxygen or at a lowered, but nonlethal, level of oxygen. Acclimation to nonlethal hypoxia (pO2 @ 15 Torr; ca. 10% air-saturation) for 48 hr significantly extended survival time during more severe hypoxia (pO2 @ 8 Torr; ca. 5% air-saturation) compared to survival of individuals with no prior hypoxic exposure. The magnitude of the acclimation effect depended upon the sex of the fish: hypoxia pretreatment increased the survival times of males by a factor of approximately 9 and that of females by a …

What Makes The Rhizobia-Legume Symbiosis So Special?, Michelle Lum

Biology Faculty Works

No abstract provided.

Sugar-Binding Activity Of Pea Lectin Enhances Heterologous Infection Of Transgenic Alfalfa Plants By Rhizobium Leguminosarum Biovar Viciae, Nancy Fujishige

Biology Faculty Works

Transgenic alfalfa (Medicago sativa L. cv Regen) roots carrying genes encoding soybean lectin or pea (Pisum sativum) seed lectin (PSL) were inoculated with Bradyrhizobium japonicum or Rhizobium leguminosarum bv viciae, respectively, and their responses were compared with those of comparably inoculated control plants. We found that nodule-like structures formed on alfalfa roots only when the rhizobial strains produced Nod factor from the alfalfa-nodulating strain, Sinorhizobium meliloti. Uninfected nodule-like structures developed on the soybean lectin-transgenic plant roots at very low inoculum concentrations, but bona fide infection threads were not detected even when B. japonicum produced the appropriate S. meliloti Nod factor. …

Secreted Euryarchaeal Microhalocins Kill Hyperthermophilic Crenarchaea, Cynthia Haseltine, Tiffany Hill, Rafael Montalvo-Rodriguez, Samantha K. Kemper, Richard F. Shand, Paul H. Blum

School of Biological Sciences: Faculty Publications

Few antibiotics targeting members of the archaeal domain are currently available for genetic studies. Since

bacterial antibiotics are frequently directed against competing and related organisms, archaea by analogy

might produce effective antiarchaeal antibiotics. Peptide antibiotic (halocin) preparations from euryarchaeal

halophilic strains S8a, GN101, and TuA4 were found to be toxic for members of the hyperthermophilic

crenarchaeal genus Sulfolobus. No toxicity was evident against representative bacteria or eukarya. Halocin S8

(strain S8a) and halocin R1 (strain GN101) preparations were cytostatic, while halocin A4 (strain TuA4)

preparations were cytocidal. Subsequent studies focused on the use of halocin A4 preparations and Sulfolobus …

Biodiversity And Decomposition In Experimental Grassland Ecosystems, Johannes M. H. Knops, David A. Wedin, David Tilman

School of Biological Sciences: Faculty Publications

We examined the impact of biodiversity on litter decomposition in an experiment that manipulated plant species richness. Using biomass originating from the experimental species richness gradient and from a species used as a common substrate, we measured rates of decomposition in litterbags in two locations: in situ in the experiment plots and in an adjacent common garden. This allowed us to separate the effects of litter quality and decomposition location on decomposition. We found that plant species richness had a significant, but minor negative effect on the quality (nitrogen concentration) of the biomass. Neither litter type nor location had a …

A Synopsis Of The Ferns And Fern Allies Of Nebraska, With Maps Of Their Distribution, Steven B. Rolfsmeier, Robert B. Kaul, David M. Sutherland

School of Biological Sciences: Faculty Publications

An annotated list and country-by-country distribution maps are presented for the 32 species of ferns and fern allies native to Nebraska, based upon field and herbarium studies and critical evaluation of the literature. Native to the state are Isoëtes melanopoda, Selaginella rupestris, five species of Equisetum, and 25 species in 18 genera of ferns. Three native species are here verified for the first time, based upon recent collections: Matteuccia struthiopteris var. pensylvanica, Ophioglossum engelmannii, and Pellacaglabella ssp. glabella. Isoëtes melanopoda was rediscovered in 2000, the first record since 1941. Rejected are published reports of …

Identification Of A Defensin From The Hemolymph Of The American Dog Tick, Dermacentor Variabilis, Robert Johns, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

Hemolymph from partially fed virgin Dermacentor variabilis females was collected following Borrelia burgdorferi challenge and assayed for antimicrobial activity against Bacillus subtilis and B. burgdorferi. A small inducible cationic peptide was identified by SDS-PAGE in the hemolymph of these ticks as early as 1h post challenge. Following purification by a three-step procedure involving sequential SepPak elution, reversed phase high performance liquid chromatography (RP-HPLC) and gel electrophoresis, the yield of the active peptide was approximately 0.1% of the total protein in the hemolymph plasma. The molecular weight, 4.2kDa, was determined by MALDI-TOF mass spectrometry. N-terminal sequencing by the Edman degradation …

Tick Immunity To Microbial Infections: Control Of Representative Bacteria In The Hard Tick Dermacentor Variabilis (Acari: Ixodidae), Robert Johns, Shane Ceraul, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

No abstract provided.

Chondrocranium And Visceral Skeleton Of Atelopus Tricolor And Atelophryniscus Chrysophorus, E O. Lavilla, Rafael O. De Sá

Biology Faculty Publications

Atelopus tricolor and Atelophryniscus chrysophorus have gastromyzophorous tadpoles. Aside from specific differences, the larval chondrocrania and visceral skeletons show several shared character states, including an almost quadrangular, open chondrocranium , cornua trabeculae with expanded tips, cartilago suprarostralis as a single element, a posteriorly projected arcus subocularis quadrati, a closed muscular tunnel, and a simplified branchial basket, with only three pairs of ceratobranchiales. They are compared with diverse character states of suctorial larvae considering them as causally related to the stream life adaptations.

Expression Of Mslec1- And Mslec2-Antisense Genes In Alfalfa Plant Lines Causes Severe Embryogenic, Developmental And Reproductive Abnormalities, Laurence M. Brill, Cory J. Evans, Ann M. Hirsch

Biology Faculty Works

Although it has been proposed that plant lectins play a number of roles, the function of these proteins in normal plant growth and development has been unclear. To analyze the functions of putative alfalfa lectin genes, lines of transgenic alfalfa plants expressing approximately half of the open reading frame of MsLEC1 or MsLEC2, in the antisense or sense orientation, were established and analyzed. The antisense plants displayed severe abnormalities in embryogenesis, and both vegetative and reproductive development were perturbed. Some differences were observed between MsLEC1- and MsLEC2-antisense plants, and abnormalities were especially severe during the early stages of development in …

"On The Heterotreme-Thoracotreme Distinction In The Eubrachyura De Saint-Laurent, 1980" , Richard V. Sternberg, Neil Cumberlidge

Journal Articles

No abstract provided.

"A New Species Of Freshwater Crab From Rukwanzi, East Africa." , R Gregory Corace, Neil Cumberlidge, Rolf Garms

Journal Articles

No abstract provided.

Rna Binding Domain Of Telomerase Reverse Transcriptase, Cary Lai, James R. Mitchell, Kathleen Collins

Biology Faculty Publications

Telomerase is a ribonucleoprotein reverse transcriptase that extends the ends of chromosomes. The two telomerase subunits essential for catalysis in vitro are the telomerase reverse transcriptase (TERT) and the telomerase RNA. Using truncations and site-specific mutations, we identified sequence elements of TERT and telomerase RNA required for catalytic activity and protein-RNA interaction for Tetrahymena thermophila telomerase. We found that the TERT amino and carboxyl termini, although evolutionarily poorly conserved, are nonetheless important for catalytic activity. In contrast, high-affinity telomerase RNA binding requires only a small region in the amino terminus of TERT. Surprisingly, the TERT region necessary and sufficient for …

A Critical Evaluation Of Research Techniques In Animal Ecology, Michelle A. Baker

Biology Faculty Publications

No abstract provided.

High Frequency Of Extra-Pair Paternity In Eastern Kingbirds, D. L. Rowe, M. T. Murphy, R. C. Feischer, Paul G. Wolf

Biology Faculty Publications

Genetic parentage in the socially monogamous and territorial Eastern Kingbird( Tyrannust tyrannus) was examined in a central New York population by multilocus DNA fingerprinting. Extra-pair young were identified in 60% (12 of 20) of nests. Of the 64 nestlings profiled, 42% were sired by extra-pair males, but no cases of conspecific brood parasitism were detected. These results are markedly different from a previous electrophoretic study of the same species in a Michigan population, which reported 39% of nestlings were unrelated to one (typically the mother, quasiparasitismo)r both (conspecificb roodp arasitism) of the putative parents. In the New York population, extra-pairp …

Patch-Clamp Analysis Of Voltage-Activated And Chemically Activated Currents In The Vomeronasal Organ Of Sternotherus Odoratus (Stinkpot/Musk Turtle), D. A. Fadool, M. Wachowiak, J. H. Brann

Biology: Faculty Publications and Other Works

The electrophysiological basis of chemical communication in the specialized olfactory division of the vomeronasal (VN) organ is poorly understood. In total, 198 patch-clamp recordings were made from 42 animals (Sternotherus odoratus, the stinkpot/musk turtle) to study the electrically and chemically activated properties of VN neurons. The introduction of tetramethylrhodamine-conjugated dextran into the VN orifice permitted good visualization of the vomeronasal neural epithelium prior to dissociating it into single neurons. Basic electrical properties of the neurons were measured (resting potential, -54.5 +/- 2.7 mV, N=11; input resistance, 6.7 +/- 1.4 G Omega, N=25; capacitance, 4.2 +/- 0.3 pF, N=22; means +/- …

Cloning Of Hsds Gene And Characterization Of The Protein From Haemophilus Influenzae Rd, Srividya Chalapatti

Seton Hall University Dissertations and Theses (ETDs)

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Yield-Per-Recruit Analysis For Black Drum, Pogonias Cromis, Along The East Coast Of The United States And Management Strategies For Chesapeake Bay, Cynthia M. Jones, Brian K. Wells

OES Faculty Publications

Black drum, Pogonias cromis along the U.S. East Coast is subject to commercial and recreational harvest. However, prior to this study no modeling had been undertaken to examine the potential for overfishing in the Chesapeake Bay region. We present evidence from yield-per-recruit models that growth overfishing of black drum is unlikely under current fishing practices in this region. Particular attention was given to fishing practices in the Chesapeake Bay region where old, large fish predominate in the commercial and recreational catches (mean age=26 years: mean total length=108.4 cm; mean weight 22.1 kg). Yield-per-recruit model results showed that growth overfishing was …

Resilience And Recovery Of Coral Reefs From Large-Scale Disturbances: Contrasting Patterns For San Salvador Island, Bahamas, And Belize, Paulette Peckol, Benjamin J. Greenstein

Arts & Sciences Faculty Publications

Coral cover and diversity are declining while macroalgal abundance is increasing in most Caribbean coral reef systems. Although a complex interaction of natural and anthropogenic disturbances is likely causal, the effects of a specific disturbance may vary dramatically for different reef systems. The coral reefs off the coasts of San Salvador Island, Bahamas and Belize, considered to be in relatively good condition, recently experienced near-direct hits by Hurricanes Floyd (1999) and Mitch (1998), respectively. In addition, NOAA scientists indicated that during 1998, tropical sea surface temperatures (SSTs) reached their highest levels above the normal annual maximum for this past century. …