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Systematic Relationships Of Natalid And Furipterid Bats, Based On Hyoid Morphology (Chiroptera: Natalidae And Furipteridae), Kosha N. Baxi '01 Apr 2001

Systematic Relationships Of Natalid And Furipterid Bats, Based On Hyoid Morphology (Chiroptera: Natalidae And Furipteridae), Kosha N. Baxi '01

Honors Projects

Themusculature of the hyoid regions of two species of bats (Order Chiroptera) from two separate families, Natalidae and Furipteridae, were examined using standard microscopic dissection techniques. Morphological variation was described and characters were scored and entered into the computer program PAUP, Phylogenetic Analysis Using Parsimony, along with characters of families previously examined by Griffiths. Cladistic analysis revealed support for the placement of Natalidae and Furipteridae together within the Superfamily Nataloidea, along with the families Thyropteridae and Myzopodidae, as recently proposed by Simmons (1998). The inclusion of Myzopodidae is surprising from a geographical standpoint. Myzopodids are endemic to Madagascar, while thyropterids, …

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Neotropical Nectar-Feeding Bats (Family Phyllostomidae) Revisited: Lingual Data Support A Recently-Proposed Molecular Phylogeny, Shawn De La Mar '01 Apr 2001

Neotropical Nectar-Feeding Bats (Family Phyllostomidae) Revisited: Lingual Data Support A Recently-Proposed Molecular Phylogeny, Shawn De La Mar '01

Honors Projects

From the early 1900s to the 1970s, all New World nectar-feeding bats were classified under the subfamily Glossophaginae. During the last few decades of the 20th century, however, several analyses supported the hypothesis that this taxon was an unnatural grouping. T. A. Griffiths (1982) proposed creating a new subfamily, the Lonchophyllinae, which would include Lonchophylla, Lionycteris, and Platalina, three genera formerly included in the Glossophaginae. This proposal raised significant controversy. A recent molecular study by R. J. Baker and colleagues (2000) examined the RAG2 gene DNA sequence in a large number of bats in the family Phyllostomidae, including Lonchophylla, Lionycteris, …

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Lipid Biochemistry Of House Wren Egg Yolk And Possible Effects On Incubation Period, Brian J. Payne '01 Apr 2001

Lipid Biochemistry Of House Wren Egg Yolk And Possible Effects On Incubation Period, Brian J. Payne '01

Honors Projects

House Wrens (Troglodytes aedon) are distributed throughout North and South America. As has been observed in many avian species, populations of House Wrens in the tropics have longer egg incubation periods than populations in temperate regions. The purpose of this study was to characterize incubation periods of a temperate population of House Wrens and to conduct a preliminary chemical analysis of the yellow and white yolk layers of House Wren eggs. The eggs were collected from a breeding population in Central Illinois from June-August 2000. Avian yolk is composed of yellow and white components, which are laid down in alternating …

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Litter Breakdown In Mountain Streams Affected By Mine Drainage: Biotic Mediation Of Abiotic Controls, Dev Niyogi, William M. Lewis Jr., Diane M. Mcknight Apr 2001

Litter Breakdown In Mountain Streams Affected By Mine Drainage: Biotic Mediation Of Abiotic Controls, Dev Niyogi, William M. Lewis Jr., Diane M. Mcknight

Biological Sciences Faculty Research & Creative Works

Breakdown of plant litter in streams was studied as an example of a major ecological process subject to change through multiple stresses associated with mine drainage. Rates of litter breakdown were measured at 27 sites in streams of the Rocky Mountains of Colorado, USA. Eight of the sites were pristine, and 19 were affected to varying degrees by mine drainage. The pH, concentrations of dissolved zinc, and deposition rates of metal oxides were measured in each stream. Rates of litter breakdown were estimated from changes in mass of willow leaves in litterbags. Biomass of shredding invertebrates in litterbags was monitored …

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The Scientific Foundations Of Habitat Conservation Plans: A Quantitative Assessment, Elaine K. Harding, Elizabeth E. Crone, Bret D. Elderd, Jonathan M. Hoekstra, Alexa J. Mckerrow, John D. Perrine, Jim Regetz, Leslie J. Rissler, Amanda G. Stanley, Eric L. Walters, Nceas Habitat Conservation Plan Working Group Apr 2001

The Scientific Foundations Of Habitat Conservation Plans: A Quantitative Assessment, Elaine K. Harding, Elizabeth E. Crone, Bret D. Elderd, Jonathan M. Hoekstra, Alexa J. Mckerrow, John D. Perrine, Jim Regetz, Leslie J. Rissler, Amanda G. Stanley, Eric L. Walters, Nceas Habitat Conservation Plan Working Group

Biological Sciences

The number of habitat conservation plans ( HCP) has risen dramatically since the first plan was written over 18 years ago. Until recently, no studies have quantitatively investigated the scientific foundations underlying these documents. As part of a larger study of HCPs, we examined 43 plans primarily to assess the availability and use of scientific data and secondarily to determine the extent of involvement by, and influence of, independent scientists within the process. Specifically, our analysis focused on five key steps taken when an HCP is developed: assessing status of a species, determining take, predicting the project effects, mitigating for …

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In Vivo Titration Of Mitomycin C Action By The Presence Of Four Escherichia Coli Genomic Regions On Multicopy Plasmid, Y. Wei, Amy Cheng Vollmer, R. A. Larossa Apr 2001

In Vivo Titration Of Mitomycin C Action By The Presence Of Four Escherichia Coli Genomic Regions On Multicopy Plasmid, Y. Wei, Amy Cheng Vollmer, R. A. Larossa

Biology Faculty Works

Mitomycin C (MMC), a DNA-damaging agent, is a potent inducer of the bacterial SOS response; surprisingly, it has not been used to select resistant mutants from wild-type Escherichia coli. MMC resistance is caused by the presence of any of four distinct E. coli genes (mdfA, gyrl, rob, and sdiA) on high-copy-number vectors. mdfA encodes a membrane efflux pump whose overexpression results in broad-spectrum chemical resistance. The gyrI (also called sbmC) gene product inhibits DNA gyrase activity in vitro, while the rob protein appears to function in transcriptional activation of efflux pumps. SdiA is a transcriptional activator of ftsQAZ genes involved …

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Bird Migration Through A Mountain Pass Studied With High Resolution Radar, Ceilometers, And Census, Timothy C. Williams , '64, J. M. Williams, P. G. Williams, P. Stokstad Apr 2001

Bird Migration Through A Mountain Pass Studied With High Resolution Radar, Ceilometers, And Census, Timothy C. Williams , '64, J. M. Williams, P. G. Williams, P. Stokstad

Biology Faculty Works

Autumnal migration was studied with high-resolution radar, ceilometer, and daily census in the area of Franconia Notch, a major pass in the northern Appalachian Mountains. Under synoptic conditions favorable for migration, broadfront movements of migrants toward the south passed over the mountains, often above a temperature inversion. Birds at lower elevations appeared to be influenced by local topography. Birds moving southwest were concentrated along the face of the mountain range. Birds appeared to deviate their flights to follow local topography through the pass. Specific migratory behavior was not associated with species or species groups. Under synoptic conditions unfavorable for southward …

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Determining Differences In The Spatial Distribution Of Forest Structure On The Kaibab Plateau: Implications For Forest Management And The Northern Goshawk, Ryan S. Miller Apr 2001

Determining Differences In The Spatial Distribution Of Forest Structure On The Kaibab Plateau: Implications For Forest Management And The Northern Goshawk, Ryan S. Miller

Other Publications in Wildlife Management

The Kaibab Plateau, in North Central Arizona, has undergone extensive change in the last 100 years due to land management practices such as logging, road building, and fire suppression. The northern goshawk (Accipiter gentilis) has been a center of controversy, due to the potential effects of silvicultural practices on goshawk breeding habitat (Reynolds-1983, Bloom et al 1986, Kennedy 1989, Crocker-Bedford 1990). Current and past research efforts on the Kaibab Plateau have mapped Goshawk nesting territories and temporal change in nesting behavior and success. However, these research efforts have not determined how long-term spatial changes in land-use activities that have influenced …

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Acid Phosphatase Activity In Human Breast Tumors, Reginald Halaby, Jafar Abdollahi, Minerva L. Martinez Apr 2001

Acid Phosphatase Activity In Human Breast Tumors, Reginald Halaby, Jafar Abdollahi, Minerva L. Martinez

Department of Biology Faculty Scholarship and Creative Works

We examined lysosomal participation in the degradation of tumor cells from human breast biopsies, utilizing the histochemical activity and localization of acid phosphatase (AP). Enzyme activities in benign and malignant lesions were compared. AP was faintly detected in normal mammary epithelia and was marked in malignant cells. The histochemical patterns of AP distribution in the breast tissues showed differences between normal and neoplastic cells. AP staining was more intense in ductal carcinoma in situ (DCIS) associated with invasive ductal carcinoma (IDC) cases compared to when IDC was present alone. These results suggest that non-invasive breast cancers, such as DCIS, may …

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Treefall Gaps And The Maintenance Of Species Diversity In A Tropical Forest, Stefan A. Schnitzer, Walter P. Carson Apr 2001

Treefall Gaps And The Maintenance Of Species Diversity In A Tropical Forest, Stefan A. Schnitzer, Walter P. Carson

Biological Sciences Faculty Research and Publications

The maintenance of species diversity by treefall gaps is a long‐standing paradigm in forest ecology. Gaps are presumed to provide an environment in which tree species of differing competitive abilities partition heterogeneous resources. The empirical evidence to support this paradigm, however, remains scarce, and some recent studies even suggest that gaps do not maintain the diversity of shade‐tolerant species. Although there is evidence that gaps maintain the diversity of pioneer trees, most of this evidence comes from studies that did not make comparisons between gaps and intact forest sites (controls). Further, nearly all studies on the maintenance of diversity by …

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Environmental Effects On Yield And Agronomic Traits Of Common Bean (Phaseolus Vulgaris L.), Tadesse Mebrahtu, Teklu Andebrhan, Ali Mohamed Apr 2001

Environmental Effects On Yield And Agronomic Traits Of Common Bean (Phaseolus Vulgaris L.), Tadesse Mebrahtu, Teklu Andebrhan, Ali Mohamed

Virginia Journal of Science

Common bean (Phaseolus vulgaris L.) demand is increasing with an alarming rate around the world, especially in Latin America, Africa, and Asia. Therefore, increase bean yield per hectare is the best way to meet the world demand rather than expansion of area under cultivation. The objectives of this experiment were to determine the genotypic variations for green bean and dry seed yield and magnitude of genotype x environment interaction effects on yield and yield components of common bean. Thirteen genotypes were planted during the 1992, 1994, and 1995 growing seasons. Genotypes were evaluated for green pod and seed …

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Isolation And Fusion Of Cotton Protoplasts, Michael H. Renfroe, Ronald C. Hartwig, Roberta H. Smith Apr 2001

Isolation And Fusion Of Cotton Protoplasts, Michael H. Renfroe, Ronald C. Hartwig, Roberta H. Smith

Virginia Journal of Science

Protoplasts were isolated from five species of Gossypium. Protoplast yield and viability were affected by incubation conditions, osmolarity, purification procedures, and cell source. Using an optimized procedure, highly viable protoplasts were isolated from cell suspensions, callus cultures, and leaf tissue of G. hirsutum, G. arboreum, G. klotzschianum, G. harknessii, and G. herbaceum. Protoplasts of G. harknessii were enucleated and successfully fused with protoplasts of G. hirsutum.

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Trans Fatty Acids In Adipose Tissue And Erythrocytes Of Irish Adults, Linda Hogan Apr 2001

Trans Fatty Acids In Adipose Tissue And Erythrocytes Of Irish Adults, Linda Hogan

Masters

Trans fatty acids (TFA) are produced by the partial hydrogenation of vegetable and marine oils. TFA are not synthesized in the human body. The fatty acid composition of adipose tissue reflects the habitual intake of TFA over the previous 1-2 years. Recent studies associate TFA with an increased serum level of low density lipoproteins (LDL) and therefore an increased risk of coronary heart disease (CHD). The objective of the present study was to assess the level of TFA in the subcutaneous fat and erythrocyte membranes of subjects from an Irish population. One fat aspirate and one blood sample were taken …

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Abp1 Is Required For Organized Cell Elongation And Division In Arabidopsis Embryogenesis, Hemayet Ullah Apr 2001

Abp1 Is Required For Organized Cell Elongation And Division In Arabidopsis Embryogenesis, Hemayet Ullah

Department of Biology Faculty Publications

To directly address the function of a putative auxin receptor designated ABP1, a reverse genetic approach was taken to identify and characterize ABP1 mutant alleles in Arabidopsis. A homozygous null mutation in ABP1 confers embryo lethality. Null mutant embryos develop normally until the early stages of the globular embryo but are unable to make the transition to a bilaterally symmetrical structure because cells fail to elongate. Cell division was also aberrant both in the suspensor and embryo proper. Antisense suppression of ABP1 in tobacco cells causes slow proliferation and eliminates auxin-induced cell elongation and reduces cell division. The complete lack …

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Ice Storm Damage To Virginia Coastal Plain Forests During The Christmas 1998 Ice Storm, Peter Elstner, Stewart Ware Apr 2001

Ice Storm Damage To Virginia Coastal Plain Forests During The Christmas 1998 Ice Storm, Peter Elstner, Stewart Ware

Virginia Journal of Science

On December 23-25, 1998, a major ice storm struck southeastern Virginia. The storm-deposited glaze ice felled trees and limbs, causing a power outage and highway blockage. Between February and April, 1999, we recorded occurrence, severity, and type of damage to trees over 2.5 cm dbh in nine mostly gently sloping plots in Matoaka Woods at the College of William and Mary. Frequency and severity of damage varied with species and with size of trees. Canopy damage occurred in 75% of large Fagus grandifolia trees, but in only 6% of small Sassafras albidum stems. As a group, small (2.5 to 15 …

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Comparison Of Spawning And Non-Spawning Substrates In Nests Of Species Of Exoglossum And Nocomis (Actinopterygii: Cyprinidae), Eugene G. Maurakis, Terre D. Green Apr 2001

Comparison Of Spawning And Non-Spawning Substrates In Nests Of Species Of Exoglossum And Nocomis (Actinopterygii: Cyprinidae), Eugene G. Maurakis, Terre D. Green

Virginia Journal of Science

Percent composition of pebble size classes from spawning and non-spawning substrates of nests were used to test the hypothesis that distribution of pebble sizes is random in nests of Exoglossum laurae, Exoglossum maxillingua, Nocomis leptocephalus, Nocomis micropogon, Nocomis platyrhynchus, and Nocomis raneyi in Virginia. In nests of the two species of Exoglossum, spawning areas (i.e., upstream bases of nests) contain significantly greater amounts of the 6.0 mm size class, and significantly smaller amounts of the 2.5 mm size class of stones than do non-spawning areas. Spawning areas (i.e., pits) in nests of N. leptocephalus contain …

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Energy Budgets, Growth Rates, And The Rmal Constraints: Toward An Integrative Approach To The Study Of Life-History Variation, Peter H. Niewiarowski Apr 2001

Energy Budgets, Growth Rates, And The Rmal Constraints: Toward An Integrative Approach To The Study Of Life-History Variation, Peter H. Niewiarowski

Biology Faculty Research

Variation in thermal constraints on activity has been hypothesized to be an important ecological source of geographic variation in growth rates of juvenile eastern fence lizards Sceloporus undulatus. However, most of the evidence to support this hypothesis is either inferential or indirect. In this study, I quantitatively compared thermal constraints on activity and their relationship to growth rates of free-ranging juvenile fence lizards from two extremes of the range of variation in growth rate (Nebraska and New Jersey) used in a reciprocal transplant experiment. I also examined energy allocation made to growth and storage by yearling lizards. Reduced growth rates …

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C2 Domains From Different Ca2+ Signaling Pathways Display Functional And Mechanistic Diversity, E. A. Nalefski, M. A. Wisner, J. Z. Chen, S. R. Sprang, M. Fukuda, K. Mikoshiba, J. J. Falke Mar 2001

C2 Domains From Different Ca2+ Signaling Pathways Display Functional And Mechanistic Diversity, E. A. Nalefski, M. A. Wisner, J. Z. Chen, S. R. Sprang, M. Fukuda, K. Mikoshiba, J. J. Falke

Biological Sciences Faculty Publications

The ubiquitous C2 domain is a conserved Ca2+-triggered membrane-docking module that targets numerous signaling proteins to membrane surfaces where they regulate diverse processes critical for cell signaling. In this study, we quantitatively compared the equilibrium and kinetic parameters of C2 domains isolated from three functionally distinct signaling proteins: cytosolic phospholipase A2-α (cPLA2-α), protein kinase C-β (PKC-β), and synaptotagmin-IA (Syt-IA). The results show that equilibrium C2 domain docking to mixed phosphatidylcholine and phosphatidylserine membranes occurs at micromolar Ca2+ concentrations for the cPLA2-α C2 domain, but requires 3- and 10-fold higher Ca2+ …

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Binding Of Urate And Caffeine To Hemocyanin Analyzed By Isothermal Titration Calorimetry, Michael A. Menze, Nadja Hellmann, Heinz Decker, Manfred K. Grieshaber Mar 2001

Binding Of Urate And Caffeine To Hemocyanin Analyzed By Isothermal Titration Calorimetry, Michael A. Menze, Nadja Hellmann, Heinz Decker, Manfred K. Grieshaber

Faculty Research & Creative Activity

Haemocyanin serves as an oxygen carrier in the haemolymph of decapod crustaceans. The oxygen-binding behaviour of the pigment is modulated by the two major anaerobic metabolites, L-lactate and urate. The binding of these two metabolites to haemocyanin has been investigated mainly indirectly by following the effectorinduced changes in the oxygen-binding properties of the respiratory pigment. Only a few direct investigations of effector binding, employing ultracentrifugation techniques and equilibrium dialysis, have been carried out. No evidence for cooperative binding for either effector was detected using these methods. However, isothermal titration calorimetry (ITC) offers a useful tool to gain additional insight into …

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Correlated Evolution Of Chloroplast Heat Shock Protein Expression In Closely Related Plant Species, Charles A. Knight, David D. Ackerly Mar 2001

Correlated Evolution Of Chloroplast Heat Shock Protein Expression In Closely Related Plant Species, Charles A. Knight, David D. Ackerly

Biological Sciences

Interspecific variation in chloroplast low molecular weight (cLMW) HSP (heat shock protein) expression was examined with respect to phylogeny, species specific leaf area, chlorophyll fluorescence, and mean environmental conditions within species ranges. Eight species of Ceanothus (Rhamnaceae) were heat shocked for 4 h at several different temperatures. Leaf samples were collected immediately after the heat shock, and cLMW HSP expression was quantified using Western blots. At 450C species from the subgenus Cerastes had significantly greater cLMW HSP expression than species from the subgenus Ceanothus. Specific leaf area was negatively correlated with cLMW HSP expression after the 45 …

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A New Aglyptorhynchus (Perciformes: Scombroidei: Blochiidae) From The Late Oligocene Of Oregon, Harry L. Fierstine Mar 2001

A New Aglyptorhynchus (Perciformes: Scombroidei: Blochiidae) From The Late Oligocene Of Oregon, Harry L. Fierstine

Biological Sciences

A partial fish skull with a nearly complete rostrum, a cup-shaped sclerotic hone, and cycloid scales (UCMP 123170) from the Yaquina Formation (late Oligocene, Oregon) is described and identified as Aglyptorhynchus maxillaris, sp. nov. Unusual features of the rostrum include a fused premaxillary segment with a low dorsal keel, and a maxilla with both a flat flange on its postero-ventral margin and a large condyle that presumably allowed dorsoventral movement of the rostrum to increase the gape. The Yaquina Formation was estimated to have been deposited at a water depth of over 100m and a sea surface temperature of at …

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Low Genetic Diversity In An Endangered Species: Recent Or Historic Pattern?, Marjorie D. Matocq, Francis X. Villablanca Mar 2001

Low Genetic Diversity In An Endangered Species: Recent Or Historic Pattern?, Marjorie D. Matocq, Francis X. Villablanca

Biological Sciences

Examining patterns of genetic diversity has become an integral component of many management plans concerning endangered species, yet interpreting the processes underlying such patterns remains challenging. We demonstrate low genetic diversity in a critically endangered small mammal population. A common interpretation of this pattern would be that it is the result of a known, recent decline in this population. We test this interpretation and find it to be incorrect. Instead, by using museum voucher specimens, we show that the pattern of low genetic diversity is historical. This study demonstrates the importance of choosing appropriate reference groups by which to interpret …

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Experimental Model Of Human Body Louse Infection Using Green Fluorescent Protein-Expressing Bartonella Quintana, Pierre-Edouard Fournier, Michael F. Minnick, Hubert Lepidi, Eric Salvo, Didier Raoult Mar 2001

Experimental Model Of Human Body Louse Infection Using Green Fluorescent Protein-Expressing Bartonella Quintana, Pierre-Edouard Fournier, Michael F. Minnick, Hubert Lepidi, Eric Salvo, Didier Raoult

Biological Sciences Faculty Publications

A laboratory colony of human body lice was experimentally infected by feeding on rabbits made artificially bacteremic with a green fluorescent protein-expressing Bartonella quintana. B. quintana was detected in the gut and feces until death but not in the eggs. The life span of the lice was not modified. The rabbit model should provide valuable clues to the role of lice in the transmission of B. quintana.

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Antibody Binding And Neutralization Of Primary And T-Cell Line-Adapted Isolates Of Human Immunodeficiency Virus Type 1, Joanne York, Kathryn E. Follis, Meg Trahey, Phillipe N. Nyambi, Susan Zolla-Pazner, Jack H. Nunberg Mar 2001

Antibody Binding And Neutralization Of Primary And T-Cell Line-Adapted Isolates Of Human Immunodeficiency Virus Type 1, Joanne York, Kathryn E. Follis, Meg Trahey, Phillipe N. Nyambi, Susan Zolla-Pazner, Jack H. Nunberg

Biological Sciences Faculty Publications

The relative resistance of human immunodeficiency virus type 1 (HIV-1) primary isolates (PIs) to neutralization by a wide range of antibodies remains a theoretical and practical barrier to the development of an effective HIV vaccine. One model to account for the differential neutralization sensitivity between Pls and laboratory (or T-cell line-adapted [TCLA]) strains of HN suggests that the envelope protein (Env) complex is made more accessible to antibody binding as a consequence of adaptation to growth in established cell lines. Here, we revisit this question using genetically related PI and TCLA viruses and molecularly cloned env genes. By using complementary …

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Review Of "Illuminating Life: Selected Papers From Cold Spring Harbor (1903-1969). Volume 1" By J. Witkowski, John B. Jenkins Mar 2001

Review Of "Illuminating Life: Selected Papers From Cold Spring Harbor (1903-1969). Volume 1" By J. Witkowski, John B. Jenkins

Biology Faculty Works

No abstract provided.

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Vertical And Horizontal Transcendence, Ursula Goodenough Mar 2001

Vertical And Horizontal Transcendence, Ursula Goodenough

Biology Faculty Research

Transcendence is explored from two perspectives: the traditional concept wherein the origination of the sacred is “out there,” and the alternate concept wherein the sacred originates “here.” Each is evaluated from the perspectives of aesthetics and hierarchy. Both forms of transcendence are viewed as essential to the full religious life.

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Contributions Of Identifiable Neurons And Neuron Classes To Lamprey Vertebrate Neurobiology, James T. Buchanan Mar 2001

Contributions Of Identifiable Neurons And Neuron Classes To Lamprey Vertebrate Neurobiology, James T. Buchanan

Biological Sciences Faculty Research and Publications

Among the advantages offered by the lamprey brainstem and spinal cord for studies of the structure and function of the nervous system is the unique identifiability of several pairs of reticulospinal neurons in the brainstem. These neurons have been exploited in investigations of the patterns of sensory input to these cells and the patterns of their outputs to spinal neurons, but no doubt these cells could be used much more effectively in exploring their roles in descending control of the spinal cord. The variability of cell positions of neurons in the spinal cord has precluded the recognition of unique spinal …

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Oxa1p Acts As A General Membrane Insertion Machinery For Proteins Encoded By Mitochondrial Dna, Kai Hell, Walter Neupert, Rosemary A. Stuart Mar 2001

Oxa1p Acts As A General Membrane Insertion Machinery For Proteins Encoded By Mitochondrial Dna, Kai Hell, Walter Neupert, Rosemary A. Stuart

Biological Sciences Faculty Research and Publications

Oxa1p is a member of the conserved Oxa1/YidC/Alb3 protein family involved in the membrane insertion of proteins. Oxa1p has been shown previously to directly facilitate the export of the N‐terminal domains of membrane proteins across the inner membrane to the intermembrane space of mitochondria. Here we report on a general role of Oxa1p in the membrane insertion of proteins. (i) The function of Oxa1p is not limited to the insertion of membrane proteins that undergo N‐terminal tail export; rather, it also extends to the insertion of other polytopic proteins such as the mitochondrially encoded Cox1p and Cox3p proteins. These are …

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Fiber-Type Susceptibility To Eccentric Contraction-Induced Damage Of Hindlimb-Unloaded Rat Al Muscles, K. P. Vijayan, Joyce L. Thompson, Kris M. Norenberg, Robert H. Fitts, Danny A. Riley Mar 2001

Fiber-Type Susceptibility To Eccentric Contraction-Induced Damage Of Hindlimb-Unloaded Rat Al Muscles, K. P. Vijayan, Joyce L. Thompson, Kris M. Norenberg, Robert H. Fitts, Danny A. Riley

Biological Sciences Faculty Research and Publications

Slow oxidative (SO) fibers of the adductor longus (AL) were predominantly damaged during voluntary reloading of hindlimb unloaded (HU) rats and appeared explainable by preferential SO fiber recruitment. The present study assessed damage after eliminating the variable of voluntary recruitment by tetanically activating all fibers in situ through the motor nerve while applying eccentric (lengthening) or isometric contractions. Muscles were aldehyde fixed and resin embedded, and semithin sections were cut. Sarcomere lesions were quantified in toluidine blue-stained sections. Fibers were typed in serial sections immunostained with antifast myosin and antitotal myosin (which highlights slow fibers). Both isometric and eccentric paradigms …

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Binding Of Urate And Caffeine To Hemocyanin Analyzed By Isothermal Titration Calorimetry., Michael Menze, Nadja Hellmann, Heinz Decker, Manfred Grieshaber Mar 2001

Binding Of Urate And Caffeine To Hemocyanin Analyzed By Isothermal Titration Calorimetry., Michael Menze, Nadja Hellmann, Heinz Decker, Manfred Grieshaber

Faculty and Staff Scholarship

Haemocyanin serves as an oxygen carrier in the haemolymph of decapod crustaceans. The oxygen-binding behaviour of the pigment is modulated by the two major anaerobic metabolites, L-lactate and urate. The binding of these two metabolites to haemocyanin has been investigated mainly indirectly by following the effectorinduced changes in the oxygen-binding properties of the respiratory pigment. Only a few direct investigations of effector binding, employing ultracentrifugation techniques and equilibrium dialysis, have been carried out. No evidence for cooperative binding for either effector was detected using these methods. However, isothermal titration calorimetry (ITC) offers a useful tool to gain additional insight into …

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