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African Genetic Diversity: Implications For Human Demographic History, Modern Human Origins, And Complex Disease Mapping, Michael Campbell, Sarah Tishkoff

Department of Biology Faculty Publications

Comparative studies of ethnically diverse human populations, particularly in Africa, are important for reconstructing human evolutionary history and for understanding the genetic basis of phenotypic adaptation and complex disease. African populations are characterized by greater levels of genetic diversity, extensive population substructure, and less linkage disequilibrium (LD) among loci compared to non-African populations. Africans also possess a number of genetic adaptations that have evolved in response to diverse climates and diets, as well as exposure to infectious disease. This review summarizes patterns and the evolutionary origins of genetic diversity present in African populations, as well as their implications for the …

A Reverse Transcriptase-Pcr Assay For Detecting Filarial Infective Larvae In Mosquitoes, Sandra J. Laney, Caitlin J. Buttaro, Sabato Visconti, Nils Pilotte, Reda M.R. Ramzy, Gary J. Weil, Steven A. Williams

Biological Sciences: Faculty Publications

Background: Existing molecular assays for filarial parasite DNA in mosquitoes cannot distinguish between infected mosquitoes that contain any stage of the parasite and infective mosquitoes that harbor third stage larvae (L3) capable of establishing new infections in humans. We now report development of a molecular L3-detection assay for Brugia malayi in vectors based on RT-PCR detection of an L3-activated gene transcript.

Methodology/Principal Findings: Candidate genes identified by bioinformatics analysis of EST datasets across the B. malayilife cycle were initially screened by PCR using cDNA libraries as templates. Stage-specificity was confirmed using RNA isolated from infected mosquitoes. Mosquitoes were collected daily …

Zoonotic Disease Emergence : A Study Of Host-Pathogen-Ecosystem Dynamics, Laurie Jeanne Dizney

Dissertations and Theses

A growing body of work demonstrates that loss of biodiversity negatively impacts ecosystem functions. One function, or service, that biodiverse ecosystems provide is suppression of zoonotic diseases, which are defined as diseases carried by wildlife hosts that can spill over into human populations. Ebola, SARS, West Nile virus, Hantavirus, Avian Influenza and Lyme disease are just a few of the recently emerging zoonotic diseases. Disease suppression has been shown for Lyme disease by the dilution effect, whereby increasing species diversity decreases disease prevalence in the host populations. But does a dilution effect apply to other disease systems? To test this …

Estimating Gene Signals From Noisy Microarray Images, Pinaki Sarder, Arye Nehorai, Paul H. Davis, Samuel L. Stanley Jr.

Biology Faculty Publications

In oligonucleotide microarray experiments, noise is a challenging problem, as biologists now are studying their organisms not in isolation but in the context of a natural environment. In low photomultiplier tube (PMT) voltage images, weak gene signals and their interactions with the background fluorescence noise are most problematic. In addition, nonspecific sequences bind to array spots intermittently causing inaccurate measurements. Conventional techniques cannot precisely separate the foreground and the background signals. In this paper, we propose analytically based estimation technique. We assume a priori spot-shape information using a circular outer periphery with an elliptical center hole. We assume Gaussian statistics …

The Dynamic Nature Of Eukaryotic Genomes, Laura Wegener Parfrey, Daniel J.G. Lahr, Laura A. Katz

Biological Sciences: Faculty Publications

Analyses of diverse eukaryotes reveal that genomes are dynamic, sometimes dramatically so. In numerous lineages across the eukaryotic tree of life, DNA content varies within individuals throughout life cycles and among individuals within species. Discovery of examples of genome dynamism is accelerating as genome sequences are completed from diverse eukaryotes. Though much is known about genomes in animals, fungi, and plants, these lineages represent only 3 of the 60-200 lineages of eukaryotes. Here, we discuss diverse genomic strategies in exemplar eukaryotic lineages, including numerous microbial eukaryotes, to reveal dramatic variation that challenges established views of genome evolution. For example, in …

An Investigation Of The Diets Of Infants Born In Ireland During The First Six Months Of Life, Roslyn Tarrant

Doctoral

Appropriate infant feeding practices play a crucial part in achieving optimal health outcomes. It is well established that the protection, promotion and support of exclusive breastfeeding during the first 6-months of life would decrease the health inequalities experienced by mothers and infants (WHO/UNICEF, 2003c). Optimal weaning practices also have significant implications for infant health, notably in relation to normal development, mineral balance and the development of obesity (Department of Health, 1994). Historically, Ireland has one of the lowest breastfeeding rates in Europe. Furthermore, prior Irish-based research indicates significant deficiencies relating to weaning practices among mothers during the first year of …

Riding The Wave: Reconciling The Roles Of Disease And Climate Change In Amphibian Declines, Michael W. Sears, Karen R. Lips, Jay Diffendorfer, Joseph R. Mendelson

Publications

Once introduced, diseases may spread quickly through new areas, infecting naive host populations, such as has been documented in Ebola virus in African primates or rabies in North American mammals. What drives the spread of the pathogenic fungus Batrachochytrium dendrobatidis (Bd), which causes chytridiomycosis, is of particular concern because it has contributed to the global
decline of amphibians. We modeled the spatiotemporal pattern of the loss of upland amphibian populations in Central and South America as a proxy for the arrival of Bd and found that amphibian declines in Central and South America are best explained by Bd spreading through …

Geographic Variation In Adult Survival And Reproductive Tactics Of The Mosquito Aedes Albopictus, Paul T. Leisnham, L M. Sala, Steven A. Juliano

Faculty Publications – Biological Sciences

Climate differences across latitude can result in seasonal constraints and selection on life history characters. Since Aedes albopictus (Skuse) invaded North America in the mid-1980s, it has spread across a range of approximate to 14 degrees latitude and populations in the north experience complete adult mortality due to cold winter temperatures that are absent in the south. Life table experiments were conducted to test for differences in the adult survival and reproductive schedules of Ae. albopictus females from two populations from the northern (Bloomington, IN [BL] and Manassas, VA [VA]; approximate to 39 degrees N) and southern (Tampa, FL and …

Louis Pasteur’S Views On Creation, Evolution, And The Genesis Of Germs, Alan L. Gillen, Frank Sherwin

Faculty Publications and Presentations

“There is no remembrance of men of old, and even those who are yet to come will not be remembered by those who follow.” Ecclesiastes 1:11 (NIV)

In past years revisionist historians have been rewriting the worldview of Christians who have made some of the major discoveries in biology and medicine. It appears that postmodern revisionists are rewriting history to support their agenda of a more “secular” explanation to science. The Judeo-Christian worldview is not politically correct in most universities. This is true in regard to past scientists such as Louis Pasteur who believed in creation. According to reliable, primary …

Microbes And The Days Of Creation, Alan L. Gillen

Faculty Publications and Presentations

The world of germs and microbes has received much attention in recent years. But where do microbes fit into the creation account? Were they created along with the rest of the plants and animals in the first week of creation, or were they created later, after the Fall? These are some questions that creation microbiologists have been asking in recent years. Ongoing research, based on the creation paradigm, appears to provide some answers to these puzzling questions. The answers to these questions are not explicit in Scripture, so the answers cannot be dogmatic. However, a reasonable extrapolation from biological data …

Antiretroviral Pre-Exposure Prophylaxis Prevents Vaginal Transmission Of Hiv-1 In Humanized Blt Mice, Paul W. Denton, Jacob D. Estes, Zhifeng Sun, Florence A. Othieno, Bangdong L. Wei, Anja K. Wege, Daniel A. Powell, Deborah A. Payne, Ashley T. Haase, J. Victor Garcia

Biology Faculty Publications

Background: Worldwide, vaginal transmission now accounts for more than half of newly acquired HIV-1 infections. Despite the urgency to develop and implement novel approaches capable of preventing HIV transmission, this process has been hindered by the lack of adequate small animal models for preclinical efficacy and safety testing. Given the importance of this route of transmission, we investigated the susceptibility of humanized mice to intravaginal HIV-1 infection.

Methods and Findings: We show that the female reproductive tract of humanized bone marrow–liver–thymus (BLT) mice is reconstituted with human CD4þ T and other relevant human cells, rendering these humanized mice …

Genomic Organization And Phylogenetic Utility Of Deer Mouse (Peromyscus Maniculatus) Lymphotoxin-Alpha And Lymphotoxin-Beta, Tiffany Richens, Aparna D.N. Palmer, Joseph Prescott, Tony Schountz

Biological Sciences Faculty Publications

BACKGROUND: Deer mice (Peromyscus maniculatus) are among the most common mammals in North America and are important reservoirs of several human pathogens, including Sin Nombre hantavirus (SNV). SNV can establish a life-long apathogenic infection in deer mice, which can shed virus in excrement for transmission to humans. Patients that die from hantavirus cardiopulmonary syndrome (HCPS) have been found to express several proinflammatory cytokines, including lymphotoxin (LT), in the lungs. It is thought that these cytokines contribute to the pathogenesis of HCPS. LT is not expressed by virus-specific CD4+ T cells from infected deer mice, suggesting a limited role for this …

Immunomodulatory Properties Of A Viral Homolog Of Human Interleukin-10 Expressed By Human Cytomegalovirus During The Latent Phase Of Infection, C Jenkins, W Garcia, M J. Godwin, Juliet V. Spencer, J Lewis Stern, Allison Abendroth, Barry Slobedman

Biology Faculty Publications

Human cytomegalovirus (HCMV) establishes a latent infection in hematopoietic cells, from which it can reactivate to cause significant disease in immunocompromised individuals. HCMV expresses a functional homolog of the immunosuppressive cytokine interleukin-10 (termed cmvIL-10), and alternate splicing of the cmvIL-10 transcript results in expression of a latency-associated cmvIL-10 transcript (LAcmvIL-10). To determine whether LAcmvIL-10 encodes immunosuppressive functions, recombinant LAcmvIL-10 protein was generated, and its impact on major histocompatibility complex class II (MHC-II) expression was examined on granulocyte macrophage progenitor cells (GM-Ps) and monocytes. LAcmvIL-10 (and cmvIL-10) downregulated MHC-II on the surfaces of both cell types. This downregulation was associated with …

Combating Amphibian Population Declines: An Investigation Of The Pathophysiology And Possible Treatments Of Batrachochytrium Dendrobatidis, Christopher A. Gaulke

Undergraduate Honors Theses

The fungus Batrachochytrium dendrobatidis has been linked to the decline of amphibians worldwide. Research has been devoted to examining the range of B. dendrobatidis and various physiological aspects of the fungus; however, little is known about how it causes mortality in individuals. Subsequently, we investigated the potential mechanisms of mortality by examining the pathogen's effect on metabolic rate and osmotic balance. In addition, we attempted to develop a field treatment for the pathogen using Itraconazol. Metabolic rates, mass, pathogen symptoms and osmotic concentrations were measured in Rana pipiens and Hyla rigilla. Results suggest symptoms are variable and individuals survive for …

Molecular Characterization And Related Aspects Of The Innate Immune Response In Ticks, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

Compared to insects, little is known about innate immunity in ticks. This chapter addresses the molecular processes that recognize non-self and the cellular and molecular processes mobilized to phagocytose, engulf, inhibit or kill invaders. We discuss the receptors that recognize pathogen associated molecular patterns (PAMPs) and the putative up-regulation of regulatory cascades that lead, ultimately, to cellular or molecular responses. We describe the molecular events that activate the cellular processes and the array of humoral factors that are mobilized against invading organisms, including antimicrobial peptides, proteases and protease inhibitors, lectins, coagulation factors and others. Special attention is directed to the …

Cis-Regulatory Analysis Of The Pigment Cell Differentiation Gene Polyketide Synthase, David Rogers

Electronic Theses and Dissertations

The analysis of Gene Regulatory Networks (GRNs) is essential to understanding the complete process of embryo development. Elucidating every gene regulatory circuit from maternal regulatory inputs all the way to the activation of differentiation gene batteries is an important step in increasing our understanding of developmental biology. In this work I study the cis-regulatory architecture of a pigment cell differentiation gene, polyketide synthase (SpPks) in the sea urchin Strongylocentrotus purpuratus. SpPks encodes an enzyme that is responsible for the biosynthesis of the sea urchin pigment echinochrome in larval pigment cells. The analysis of the promoter of a differentiation gene will …

Gliotoxin Production In Aspergillus Fumigatus, Susan Musyimi

Theses and Dissertations

Aspergillus fumigalus is a ubiquitous fungus that causes an infection called aspergillosis in immune-compromised surgery patients (Latge, 2001, 384; Bok et al. 2006). Aspergillosis cases have increased in the past decade due to the increasing number of patients undergoing immunosuppressive therapy and receiving organ transplants (Bok et al. 2006). Although there is still disagreement as to the causative agent of the symptoms accompanying aspergillosis, many scientists suspect that the compound, gliotoxin, plays a major role, hi this study, we compared the amounts of gliotoxin produced from clinical and environmental isolates of A. fumigatus. We hypothesized that the amount of gliotoxin …

Tracing Sperm In Multiply-Mated Female Anastrepha Suspensa, (Diptera:Tephridae), Preeti Dhakal

Masters Theses

Anastrepha suspensa females have four different sites of sperm storage in their reproductive tract, may mate with more than one male, and store sperm in differing amounts in each organ after copulation. In order to study the dynamics of sperm storage patterns and subsequent paternity outcomes, a method was developed for both genotyping and quantifying sperm in the spermathecae. Spermathecae were isolated and sonicated to remove maternal cells, and subsequently crushed between two microslides to release sperm from the capsule. After DNA isolation, microsatellite loci could be amplified by PCR for fragment analysis. A newly developed method was then used …

Determination Of Antimicrobial And Antioxidant Activities Of Turkish Endemic Salvia Halophila Hedge, Sevi̇l Albayrak, Ahmet Aksoy, Ergi̇n Hamzaoğlu

Turkish Journal of Biology

In this study, the antioxidant activity of ethanol extract of Salvia halophila Hedge (Lamiaceae) was evaluated by 2 antioxidant assays, including phosphomolybdenum reduction and free radical scavenging activity. The ethanol extract showed free radical scavenging activity with IC_{50} of 67.73 \mug/mL in 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The antioxidant activity of the extract was found to be 84.87 ± 0.7 mg ascorbic acid equivalent (AAE)/g extract in phosphomolybdenum assay. In the addition to the antioxidant activity of the extract, the total phenolic content was measured. Total phenolic content of ethanol extract was found to be 8.21 ± 0.0 mg gallic acid equivalent …

An Unidentified Filarial Species And Its Impact On Fitness In Wild Populations Of The Black-Footed Ferret (Mustela Nigripes), Samantha M. Wisely, Jo Gayle Howard, Steven A. Williams, Odile Bain, Rachel M. Santymire, Katherine D. Bardsley, Elizabeth S. Williams

Biological Sciences: Faculty Publications

Disease can threaten the restoration of endangered species directly by substantially decreasing host survival or indirectly via incremental decreases in survival and reproduction. During a biomedical survey of reintroduced populations of the highly endangered black-footed ferret from 2002 to 2005, microfilariae discovered in the blood were putatively identified as Dirofilaria immitis, and widespread screening was initiated using a commercially available antigen-based ELISA test. A subset of animals (n = 16) was screened for D. immitis using a highly sensitive PCR-based assay. Microfilariae were also molecularly and morphologically characterized. Of 198 animals at six reintroduction sites, 12% had positive results using …

Editorial, First Science And Policy Issue, Jscas

Journal of the South Carolina Academy of Science

No abstract provided.

A Call For A Statewide Bioinformatics Institute, John R. Rose

Journal of the South Carolina Academy of Science

No abstract provided.

Bioactivities Of The Various Extracts And Essential Oils Of Salvia Limbata C.A.Mey. And Salvia Sclarea L., Hati̇ce Öğütçü, Atalay Sökmen, Münevver Sökmen, Moschos Polissiou, Julia Serkedjieva, Di̇mi̇tra Daferera, Fi̇kretti̇n Şahi̇n, Özlem Bariş, Medi̇ne Güllüce

Turkish Journal of Biology

The present study evaluated the in vitro antimicrobial, antioxidant, and antiviral activities of the essential oil and various extracts of Salvia limbata C.A.Mey. and Salvia sclarea L., as well as the content of its essential oil. The activities of essential oils were tested against a wide range of human-, plant-, and food-borne microorganisms. A total of 55 microbial organisms belonging to 35 bacteria and 19 fungi and yeast species were tested using disk diffusion, micro dilution, and micro-well dilution. The essential oils were found to possess antimicrobial activity against some of the tested fungi, while no activity was observed against …

Sensitivity Of Kinetoplastids To Aminoglycoside: Correlation With The 3’ Region Of The Small Subunit Rrna Gene, A. S. Hamad Elgazwy, Masoom M. Yasinzai

Turkish Journal of Biology

In vitro culture systems were used to assess the growth inhibition of kinetoplastids by a variety of aminoglycosides. The parasites were allowed to grow to the stationary phase in the presence of varying concentrations of the drugs. The IC-50 for every drug was calculated by comparison with the control. The sensitivity of various leishmanial strains to these drugs was in the order of: G418 > hygromycin > paromomycin > neomycin; however, under our assay conditions gentamycin and kanamycin were non-leishmanicidal. The effects of the drugs on the intracellular form of the parasite in the macrophage cell line were also tested. Other kinetoplastids, such …

Genome-Wide Compensatory Changes Accompany Drug-Selected Mutations In The Plasmodium Falciparum Crt Gene, Hongying Jiang, Jigar J. Patel, Ming Yi, Jianbing Mu, Jinhui Ding, Robert Stephens, Roland A. Cooper, Michael T. Ferdig, Xin-Zhuan Su

Biological Sciences Faculty Publications

Mutations in PfCRT (Plasmodium falciparum chloroquine-resistant transporter), particularly the substitution at amino acid position 76, confer chloroquine (CQ) resistance in P. falciparum. Point mutations in the homolog of the mammalian multidrug resistance gene (pfmdr1) can also modulate the levels of CQ response. Moreover, parasites with the same pfcrt and pfmdr1 alleles exhibit a wide range of drug sensitivity, suggesting that additional genes contribute to levels of CQ resistance (CQR). Reemergence of CQ sensitive parasites after cessation of CQ use indicates that changes in PfCRT are deleterious to the parasite. Some CQR parasites, however, persist in the …

Historical Mammal Extinction On Christmas Island (Indian Ocean) Correlates With Introduced Infectious Disease, Kelly B. Wyatt, Paula F. Campos, M. Thomas P. Gilbert, Sergios-Orestis Kolokotronis, Wayne H. Hynes, Rob Desalle, Peter Daszak, Ross D.E. Macphee, Alex D. Greenwood

Biological Sciences Faculty Publications

It is now widely accepted that novel infectious disease can be a leading cause of serious population decline and even outright extinction in some invertebrate and vertebrate groups (e. g., amphibians). In the case of mammals, however, there are still no well-corroborated instances of such diseases having caused or significantly contributed to the complete collapse of species. A case in point is the extinction of the endemic Christmas Island rat (Rattus macleari): although it has been argued that its disappearance ca. AD 1900 may have been partly or wholly caused by a pathogenic trypanosome carried by fleas hosted …

A Survey Of Carrion And Burying Beetles (Coleoptera:Silphidae) In Mchenry County, Illinois, David Suhrbur

Masters Theses

This study compared the occurrence of beetles in the family Silphidae using historical collection records with that of field collections from five different sites within McHenry County. The five sites include: Glacial Park, Woodstock, Silver Creek, Rush Creek, and Coral Woods. Historically, 11 known silphid species have been found in McHenry County, compared with seven species found during this study' collection period.

Percentages of silphid species at each site was calculated, as well as total number of individuals sampled, and two indices of diversity (Shannon-Weiner and Simpson's) were applied to both current and historical collection data. The historical collection (when …

Transcriptional Response Of Mexican Axolotls To Ambystoma Tigrinum Virus (Atv) Infection, J. D. Cotter, A. Storfer, Robert B. Page, C. K. Beachy, S. R. Voss

Biology Faculty Publications (Archived)

Background: Very little is known about the immunological responses of amphibians to pathogens that are causing global population declines. We used a custom microarray gene chip to characterize gene expression responses of axolotls (Ambystoma mexicanum) to an emerging viral pathogen, Ambystoma tigrinum virus (ATV). Result: At 0, 24, 72, and 144 hours post-infection, spleen and lung samples were removed for estimation of host mRNA abundance and viral load. A total of 158 up-regulated and 105 down-regulated genes were identified across all time points using statistical and fold level criteria. The presumptive functions of these genes suggest a robust innate immune …

Laboratory Diagnosis Of Clostridium Difficile In The Republic Of Ireland: A Survey Of Irish Microbiology Laboratories., Denise Drudy, F. Fitzpatrick, A. Oza, A. Gilleece, A. M. O’Byrne

Articles

The Health Protection Surveillance Centre (HPSC) established a group to produce national guidelines for Clostridium difficile in Ireland in 2006. A laboratory questionnaire was distributed to determine current C. difficile diagnostic practices. Twenty-nine out of 44 laboratories providing C. difficile diagnostic services to 34 hospitals responded. Twenty-five out of 29 (86%) laboratories processed specimens for C. difficile and four (13.8%) forwarded specimens to another laboratory. Sixteen laboratories (64%) processed specimens for other healthcare facilities. None routinely examined stool for C. difficile, seven (28%) examined specimens only when requested to do so and 18 (72%) used specific selection criteria, including testing …

Update Of Clostridium Difficile Infection Due To Pcr Ribotype 027 In Europe, 2008, Denise Drudy, E. J. Kuijper, F. Barbut, J. S. Brazier

Articles

Since the emergence of a new virulent strain of Clostridium difficile characterised as toxinotype III, North American pulsedfield type 1 (NAP1), restriction-endonuclease analysis group type BI and PCR-ribotype 027 (Type 027), multiple outbreaks have been reported in North America and Europe [1-9]. The increased virulence of C. difficile Type 027 is thought to be associated with a 1 base pair deletion at position 117 of the tcdC gene which leads to an increased or prolonged production of toxins A and B, and possibly the production of a binary toxin [1-3]. However, these virulence factors are not unique for Type 027 …