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Full-Text Articles in Biology

Defining The Risk Of Zika And Chikungunya Virus Transmission In Human Population Centers Of The Eastern United States, Carrie A. Manore, Richard S. Ostfeld, Folashade B. Agusto, Holly Gaff, Shannon L. Ladeau Jan 2017

Defining The Risk Of Zika And Chikungunya Virus Transmission In Human Population Centers Of The Eastern United States, Carrie A. Manore, Richard S. Ostfeld, Folashade B. Agusto, Holly Gaff, Shannon L. Ladeau

Biological Sciences Faculty Publications

The recent spread of mosquito-transmitted viruses and associated disease to the Americas motivates a new, data-driven evaluation of risk in temperate population centers. Temperate regions are generally expected to pose low risk for significant mosquito-borne disease; however, the spread of the Asian tiger mosquito (Aedes albopictus) across densely populated urban areas has established a new landscape of risk. We use a model informed by field data to assess the conditions likely to facilitate local transmission of chikungunya and Zika viruses from an infected traveler to Ae. albopictus and then to other humans in USA cities with variable human …


Abiotic Factors Contributing To The Survival Of Three Tick Species In Southeastern Virginia, Amblyomma Americanum (Lone Star Tick), Dermacentor Variabilis (American Dog Tick), And Amblyomma Maculatum (Gulf Coast Tick), Lindsey A. Bidder Oct 2016

Abiotic Factors Contributing To The Survival Of Three Tick Species In Southeastern Virginia, Amblyomma Americanum (Lone Star Tick), Dermacentor Variabilis (American Dog Tick), And Amblyomma Maculatum (Gulf Coast Tick), Lindsey A. Bidder

Biological Sciences Theses & Dissertations

Amblyomma americanum, Amblyomma maculatum, and Dermacentor variabilis are hard-bodied ticks in the Hampton Roads area of southeastern Virginia. This study consisted of two field projects focused on these tick species. To estimate the off-host survival of local tick species, a capture-mark-recapture (CMR) study was performed. An environmental survival study was performed to quantify the ability of these three tick species to survive in situ. Four field sites were used in the Hampton Roads region covering a variety of habitat types and vegetation; specifically two drier, upland field sites and two flood-prone sites. CMR was conducted from May through …


Genomic Insights Into The Ixodes Scapularis Tick Vector Of Lyme Disease, Monika Gulia-Nuss, Andrew B. Nuss, Jason M. Meyer, Daniel E. Sonenshine, R. Michael Roe, Robert M. Waterhouse, David B. Sattelle, Jose De La Fuente, Jose M. Ribeiro, Karine Megy Jan 2016

Genomic Insights Into The Ixodes Scapularis Tick Vector Of Lyme Disease, Monika Gulia-Nuss, Andrew B. Nuss, Jason M. Meyer, Daniel E. Sonenshine, R. Michael Roe, Robert M. Waterhouse, David B. Sattelle, Jose De La Fuente, Jose M. Ribeiro, Karine Megy

Biological Sciences Faculty Publications

Ticks transmit more pathogens to humans and animals than any other arthropod. We describe the 2.1 Gbp nuclear genome of the tick, Ixodes scapularis (Say), which vectors pathogens that cause Lyme disease, human granulocytic anaplasmosis, babesiosis and other diseases. The large genome reflects accumulation of repetitive DNA, new lineages of retro-transposons, and gene architecture patterns resembling ancient metazoans rather than pancrustaceans. Annotation of scaffolds representing ~57% of the genome, reveals 20,486 protein-coding genes and expansions of gene families associated with tick-host interactions. We report insights from genome analyses into parasitic processes unique to ticks, including host 'questing', prolonged feeding, cuticle …


Behavioral Immunity Suppresses An Epizootic In Caribbean Spiny Lobsters, Mark J. Butler Iv, Donald C. Behringer Jr., Thomas W. Dolan Iii, Jessica Moss, Jeffrey D. Shields Jun 2015

Behavioral Immunity Suppresses An Epizootic In Caribbean Spiny Lobsters, Mark J. Butler Iv, Donald C. Behringer Jr., Thomas W. Dolan Iii, Jessica Moss, Jeffrey D. Shields

Biological Sciences Faculty Publications

Sociality has evolved in a wide range of animal taxa but infectious diseases spread rapidly in populations of aggregated individuals, potentially negating the advantages of their social interactions. To disengage from the coevolutionary struggle with pathogens, some hosts have evolved various forms of "behavioral immunity"; yet, the effectiveness of such behaviors in controlling epizootics in the wild is untested. Here we show how one form of behavioral immunity (i.e., the aversion of diseased conspecifics) practiced by Caribbean spiny lobsters (Panulirus argus) when subject to the socially transmitted PaV1 virus, appears to have prevented an epizootic over a large seascape. We …


Comparative Population Genetics Of Two Invading Ticks: Evidence Of The Ecological Mechanisms Underlying Tick Range Expansions, Robyn Nadolny, Holly Gaff, Jens Carlsson, David Gauthier Jan 2015

Comparative Population Genetics Of Two Invading Ticks: Evidence Of The Ecological Mechanisms Underlying Tick Range Expansions, Robyn Nadolny, Holly Gaff, Jens Carlsson, David Gauthier

Biological Sciences Faculty Publications

Two species of ixodid tick, Ixodes affinis Neumann and Amblyomma maculatum Koch, are simultaneously expanding their ranges throughout the mid-Atlantic region of the US. Although we have some understanding of the ecology and life history of these species, the ecological mechanisms governing where and how new populations establish and persist are unclear. To assess population connectivity and ancestry, we sequenced a fragment of the 16S mitochondrial rRNA gene from a representative sample of individuals of both species from populations throughout the eastern US. We found that despite overlapping host preferences throughout ontogeny, each species exhibited very different genetic and geographic …


Mutations In The Plasmodium Falciparum Chloroquine Resistance Transporter, Pfcrt, Enlarge The Parasite's Food Vacuole And Alter Drug Sensitivities, Serena Pulcini, Henry M. Staines, Andrew H. Lee, Sarah H. Shafik, Guillaume Bouyer, Catherine M. Moore, Daniel A. Daley, Matthew J. Hoke, Lindsey M. Altenhofen, Heather J. Painter, Jainbing Mu, David J.P. Ferguson, Manuel Llinás, Rowena E. Martin, David A. Fidock, Roland A. Cooper, Sanjeev Krishna Jan 2015

Mutations In The Plasmodium Falciparum Chloroquine Resistance Transporter, Pfcrt, Enlarge The Parasite's Food Vacuole And Alter Drug Sensitivities, Serena Pulcini, Henry M. Staines, Andrew H. Lee, Sarah H. Shafik, Guillaume Bouyer, Catherine M. Moore, Daniel A. Daley, Matthew J. Hoke, Lindsey M. Altenhofen, Heather J. Painter, Jainbing Mu, David J.P. Ferguson, Manuel Llinás, Rowena E. Martin, David A. Fidock, Roland A. Cooper, Sanjeev Krishna

Biological Sciences Faculty Publications

Mutations in the Plasmodium falciparum chloroquine resistance transporter, PfCRT, are the major determinant of chloroquine resistance in this lethal human malaria parasite. Here, we describe P. falciparum lines subjected to selection by amantadine or blasticidin that carry PfCRT mutations (C101F or L272F), causing the development of enlarged food vacuoles. These parasites also have increased sensitivity to chloroquine and some other quinoline antimalarials, but exhibit no or minimal change in sensitivity to artemisinins, when compared with parental strains. A transgenic parasite line expressing the L272F variant of PfCRT confirmed this increased chloroquine sensitivity and enlarged food vacuole phenotype. Furthermore, the introduction …


Transmission-Blocking Vaccines: Focus On Anti-Vector Vaccines Against Tick-Borne Diseases, Girish Neelakanta, Hameeda Sultana Jan 2015

Transmission-Blocking Vaccines: Focus On Anti-Vector Vaccines Against Tick-Borne Diseases, Girish Neelakanta, Hameeda Sultana

Biological Sciences Faculty Publications

Tick-borne diseases are a potential threat that account for significant morbidity and mortality in human population worldwide. Vaccines are not available to treat several of the tick-borne diseases. With the emergence and resurgence of several tick-borne diseases, emphasis on the development of transmission-blocking vaccines remains increasing. In this review, we provide a snap shot on some of the potential candidates for the development of anti-vector vaccines (a form of transmission-blocking vaccines) against wide range of hard and soft ticks that include Ixodes, Haemaphysalis, Dermacentor, Amblyomma, Rhipicephalus and Ornithodoros species.


Transcriptome Of The Female Synganglion Of The Black-Legged Tick Ixodes Scapularis (Acari: Ixodidae) With Comparison Between Illumina And 454 Systems, Noble Egekwu, Daniel E. Sonenshine, Brooke W. Bissinger, R. Michael Roe Jul 2014

Transcriptome Of The Female Synganglion Of The Black-Legged Tick Ixodes Scapularis (Acari: Ixodidae) With Comparison Between Illumina And 454 Systems, Noble Egekwu, Daniel E. Sonenshine, Brooke W. Bissinger, R. Michael Roe

Biological Sciences Faculty Publications

Illumina and 454 pyrosequencing were used to characterize genes from the synganglion of female Ixodes scapularis. GO term searching success for biological processes was similar for samples sequenced by both methods. However, for molecular processes, it was more successful for the Illumina samples than for 454 samples. Functional assignments of transcripts predicting neuropeptides, neuropeptide receptors, neurotransmitter receptors and other genes of interest was done, supported by strong e-values (<-6), and high consensus sequence alignments. Transcripts predicting 15 putative neuropeptide prepropeptides ((allatostatin, allatotropin, bursicon α, corticotropin releasing factor (CRF), CRF-binding protein, eclosion hormone, FMRFamide, glycoprotein A, insulin-like peptide, ion transport peptide, myoinhibitory peptide, inotocin ( = neurophysin-oxytocin), Neuropeptide F, sulfakinin and SIFamide)) and transcripts predicting receptors for 14 neuropeptides (allatostatin, calcitonin, cardioacceleratory peptide, corazonin, CRF, eclosion hormone, gonadotropin-releasing hormone/AKH-like, insulin-like peptide, neuropeptide F, proctolin, pyrokinin, SIFamide, sulfakinin and tachykinin) are reported. Similar to Dermacentor variabilis, we found transcripts matching pro-protein convertase, essential for converting neuropeptide hormones to their mature form. Additionally, transcripts predicting 6 neurotransmitter/neuromodulator receptors (acetylcholine, GABA, dopamine, glutamate, octopamine and …


Comparison Of Phenology And Pathogen Prevalence, Including Infection With The Ehrlichia Muris-Like (Eml) Agent, Of Ixodes Scapularis Removed From Soldiers In The Midwestern And Northeastern United States Over A 15 Year Period (1997-2012), Ellen Stromdahl, Sarah Hamer, Sarah Jenkins, Lynne Sloan, Phillip Williamson, Erik Foster, Robyn Nadolny, Chad Elkins, Mary Vince, Bobbi Pritt Jan 2014

Comparison Of Phenology And Pathogen Prevalence, Including Infection With The Ehrlichia Muris-Like (Eml) Agent, Of Ixodes Scapularis Removed From Soldiers In The Midwestern And Northeastern United States Over A 15 Year Period (1997-2012), Ellen Stromdahl, Sarah Hamer, Sarah Jenkins, Lynne Sloan, Phillip Williamson, Erik Foster, Robyn Nadolny, Chad Elkins, Mary Vince, Bobbi Pritt

Biological Sciences Faculty Publications

Background: Since 1997, human-biting ticks submitted to the Department of Defense Human Tick Test Kit Program (HTTKP) of the US Army Public Health Command have been tested for pathogens by PCR. We noted differences in the phenology and infection prevalence among Ixodes scapularis ticks submitted from military installations in different geographic regions. The aim of this study was to characterize these observed differences, comparing the phenology and pathogen infection rates of I. scapularis submitted from soldiers at two sites in the upper Midwest ( Camp Ripley, MN, and Ft. McCoy, WI) and one site in the northeastern US (Ft. Indiantown …


In Vitro Propagation Of Candidatus Rickettsia Andeanae Isolated From Amblyomma Maculatum, Alison Luce-Fedrow, Chelsea Wright, Holly D. Gaff, Daniel E. Sonenshine, Wayne L. Hynes, Allen L. Richards Jan 2012

In Vitro Propagation Of Candidatus Rickettsia Andeanae Isolated From Amblyomma Maculatum, Alison Luce-Fedrow, Chelsea Wright, Holly D. Gaff, Daniel E. Sonenshine, Wayne L. Hynes, Allen L. Richards

Biological Sciences Faculty Publications

Candidatus Rickettsia andeanae was identified during an investigation of a febrile outbreak in northwestern Peru (2002). DNA sequencing from two ticks (Amblyomma maculatum, Ixodes boliviensis) collected during the investigation revealed a novel Rickettsia agent with similarity to the spotted fever group rickettsiae. Since then, Candidatus R. similar to andeanae has been detected in A. maculatum ticks collected in the southeastern and southcentral United States, Argentina, and Peru. To date, Candidatus R. andeanae has not been successfully cultivated in the laboratory. We present evidence for the continuous cultivation in three cell lines of Candidatus R. similar to …


Molecular Characterization And Related Aspects Of The Innate Immune Response In Ticks, Daniel E. Sonenshine, Wayne L. Hynes Jan 2008

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 …


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 Jan 2008

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 …


Tissue And Life Stage Distribution Of A Defensin-Like Gene In The Lone Star Tick Amblyomma Americanum, S. Michelle Todd, Daniel E. Sonenshine, Wayne L. Hynes Jan 2007

Tissue And Life Stage Distribution Of A Defensin-Like Gene In The Lone Star Tick Amblyomma Americanum, S. Michelle Todd, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

The transcript sequence of the Amblyomma americanum Linnaeus (Acari: Ixodidae) defensin, termed amercin (amn), was ascertained and a 219-bp amn coding region identified. The gene encodes a 72-amino acid prepropeptide with a putative 37-amino acid mature peptide. This gene shows little similarity to either of the defensins from Amblyomma hebraeum Koch, the only other Amblyomma species for which a defensin has been described. Sequence comparisons with other tick defensins reveal amn to be shorter (6 bp or 2 amino acids) than the Ixodes scapularis Linnaeus (Acari: Ixodidae) and Dermacentor variabilis (Say) (Acari: Ixodidae) defensin sequences. The amercin prepropeptide …


A Defensin-Like Gene Expressed In The Black-Legged Tick, Ixodes Scapularis (Acari: Ixodidae), Wayne L. Hynes, S. M. Ceraul, S. M. Todd, K. C. Seguin, Daniel E. Sonenshine Jan 2005

A Defensin-Like Gene Expressed In The Black-Legged Tick, Ixodes Scapularis (Acari: Ixodidae), Wayne L. Hynes, S. M. Ceraul, S. M. Todd, K. C. Seguin, Daniel E. Sonenshine

Biological Sciences Faculty Publications

The black-legged tick Ixodes scapularis linnaeus (Acari: Ixodidae) is an important vector of microbial pathogens. Knowledge of the tick's innate immune response, particularly defensin and other antimicrobial peptides, is important for understanding how microbes survive in this tick. A defensin gene (slnA) from I. scapularis was obtained by reverse transcription-polymerase chain reaction (RT-PCR) using mRNA extracted from tissues of female ticks. RT-PCR indicated the gene was expressed in the midgut, haemocytes, and fat-body, although no evidence of a peptide was found. Sequencing a cloned cDNA fragment revealed a 225 bp open reading frame encoding a 74 amino acid pre-prodefensin, including …


Glass Capillary Tube Feeding: A Method For Infecting Nymphal Ixodes Scapularis (Acari: Ixodidae) With The Lyme Disease Spirochete Borrelia Burgdorferi, Anne H. Broadwater, Daniel E. Sonenshine, Wayne L. Hynes, Shane Ceraul, Aravinda M. De Silva Jan 2002

Glass Capillary Tube Feeding: A Method For Infecting Nymphal Ixodes Scapularis (Acari: Ixodidae) With The Lyme Disease Spirochete Borrelia Burgdorferi, Anne H. Broadwater, Daniel E. Sonenshine, Wayne L. Hynes, Shane Ceraul, Aravinda M. De Silva

Biological Sciences Faculty Publications

We evaluated an artificial capillary feeding method to infect nymphal Ixodes scapularis (Say) ticks with Borrelia burgdorferi, the causative agent of Lyme disease. Thirty to 70% of the nymphs were infected after feeding for 2.5 h from glass capillary tubes filled with a solution of spirochetes. Capillary infection was stable and persisted in the nymphs for at least 10 d after feeding. Capillary feeding also maintained natural vector competence patterns because I. scapularis ticks acquired infection unlike Dermacentor variablis (Say), which did not become infected. Capillary infected I. scapularis nymphs were capable of transmitting the infection to naive mice …


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 Jan 2001

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 …


Identification Of A Defensin From The Hemolymph Of The American Dog Tick, Dermacentor Variabilis, Robert Johns, Daniel E. Sonenshine, Wayne L. Hynes Jan 2001

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 Jan 2001

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.


Evidence Of A Neurogenic Component During Ige-Mediated Inflammation In Murine Skin, Victoria Jean Cavanaugh Jul 1990

Evidence Of A Neurogenic Component During Ige-Mediated Inflammation In Murine Skin, Victoria Jean Cavanaugh

Biological Sciences Theses & Dissertations

The direct stimulation of sensory nerves or the intradermal injection of neuropeptides triggers a cutaneous inflammatory response that involves the degranulation of mast cells. These neurogenic inflammatory reactions are physiologically similar to IgE-mediated hypersensitivity responses, which also depend on mast cells. Although non-antigenic stimuli distinguish neurogenic from IgE-mediated inflammation, the similarity of their effector stages suggested that peripheral nerves may also participate in lgE-mediated responses. To examine this hypothesis, IgE responses were elicited in denervated skin. A murine model was developed where the footpad was denervated by surgically removing a 2 mm segment of the sciatic nerve, proximal to the …