Publications

ecdysis triggering hormone signaling in arthropods.	ecdysis triggering hormones (eths) from endocrine inka cells initiate the ecdysis sequence through action on central neurons expressing eth receptors (ethr) in model moth and dipteran species. we used various biochemical, molecular and blast search techniques to detect these signaling molecules in representatives of diverse arthropods. using peptide isolation from tracheal extracts, cdna cloning or homology searches, we identified eths in a variety of hemimetabolous and holometabolous insects. m ...	2010	19951734
molecular identification of salp15, a key salivary gland protein in the transmission of lyme disease spirochetes, from ixodes persulcatus and ixodes pacificus (acari: ixodidae).	salp15 is a multifunctional protein, vital to the tick in its need to obtain vertebrate host blood without stimulating a host inflammatory and immune response. the salpl5 protein from both ixodes scapularis say and ixodes ricinus (l.), the principal vectors of the lyme disease spirochete in eastern north america and europe, respectively, have been well characterized and found to bind the murine cd4 receptor, dc-sign, and the ospc protein of borrelia burgdorferi. in the current study, we characte ...	2009	19960697
update on powassan virus: emergence of a north american tick-borne flavivirus.	powassan virus (pow) (flaviviridae: flavivirus) is the cause of rare but severe neuroinvasive disease in north america and russia. the virus is transmitted among small- and medium-sized mammals by ixodid ticks. human infections occur via spillover from the main transmission cycle(s). since the late 1990s, the incidence of human disease seems to be increasing. in addition, pow constitutes a genetically diverse group of virus genotypes, including deer tick virus, that are maintained in distinct en ...	2010	19961325
tick-borne agents in rodents, china, 2004-2006.	a total of 705 rodents from 6 provinces and autonomous regions of mainland people's republic of china were tested by pcrs for tick-borne agents (anaplasma phagocytophilum, borrelia burgdorferi sensu lato, spotted fever group rickettsiae, and francisella tularensis). infection rates were 5.5%, 6.7%, 9.1% and 5.0%, respectively. eighteen (2.6%) rodents of 10 species were positive for 2 or 3 agents. sequence analysis of pcr products confirmed the presence and genotypes of detected agents. these fin ...	2009	19961668
endosymbionts of acanthamoeba isolated from domestic tap water in korea.	in a previous study, we reported our discovery of acanthamoeba contamination in domestic tap water; in that study, we determined that some acanthamoeba strains harbor endosymbiotic bacteria, via our molecular characterization by mitochondrial dna restriction fragment length polymorphism (mt dna rflp). five (29.4%) among 17 acanthamoeba isolates contained endosymbionts in their cytoplasm, as demonstrated via orcein staining. in order to estimate their pathogenicity, we conducted a genetic charact ...	2009	19967080
infection of the endothelium by members of the order rickettsiales.	the vascular endothelium is the main target of a limited number of infectious agents, rickettsia, ehrlichia ruminantium, and orientia tsutsugamushi are among them. these arthropod-transmitted obligately-intracellular bacteria cause serious systemic diseases that are not infrequently lethal. in this review, we discuss the bacterial biology, vector biology, and clinical aspects of these conditions with particular emphasis on the interactions of these bacteria with the vascular endothelium and how ...	2009	19967137
anticoagulant activity of a sulfated galactan: serpin-independent effect and specific interaction with factor xa.	an algal sulfated galactan has high anticoagulant and antithrombotic activities. its serpin-dependent anticoagulant action is due to promoting thrombin and factor (f)xa inhibition by antithrombin and heparin cofactor ii. here, we evaluated the anticoagulant effect of the algal sulfated galactan using serpin-free plasma. in contrast to heparin, the sulfated galactan is still able to prolong coagulation time and delay thrombin and fxa generation in serpin-free plasma. we further investigated this ...	2009	19967150
ineffectiveness of tigecycline against persistent borrelia burgdorferi.	the effectiveness of a new first-in-class antibiotic, tigecycline (glycylcycline), was evaluated during the early dissemination (1 week), early immune (3 weeks), or late persistent (4 months) phases of borrelia burgdorferi infection in c3h mice. mice were treated with high or low doses of tigecycline, saline (negative-effect controls), or a previously published regimen of ceftriaxone (positive-effect controls). infection status was assessed at 3 months after treatment by culture, quantitative os ...	2010	19995919
niche partitioning of borrelia burgdorferi and borrelia miyamotoi in the same tick vector and mammalian reservoir species.	the lyme borreliosis agent borrelia burgdorferi and the relapsing fever group species borrelia miyamotoi co-occur in the united states. we used species-specific, quantitative polymerase chain reaction to study both species in the blood and skin of peromyscus leucopus mice and host-seeking ixodes scapularis nymphs at a connecticut site. bacteremias with b. burgdorferi or b. miyamotoi were most prevalent during periods of greatest activity for nymphs or larvae, respectively. whereas b. burgdorferi ...	2009	19996447
central role of the holliday junction helicase ruvab in vlse recombination and infectivity of borrelia burgdorferi.	antigenic variation plays a vital role in the pathogenesis of many infectious bacteria and protozoa including borrelia burgdorferi, the causative agent of lyme disease. vlse, a 35 kda surface-exposed lipoprotein, undergoes antigenic variation during b. burgdorferi infection of mammalian hosts, and is believed to be a critical mechanism by which the spirochetes evade immune clearance. random, segmental recombination between the expressed vlse gene and adjacent vls silent cassettes generates a lar ...	2009	19997622
identification of a calcitonin-like diuretic hormone that functions as an intrinsic modulator of the american lobster, homarus americanus, cardiac neuromuscular system.	in insects, a family of peptides with sequence homology to the vertebrate calcitonins has been implicated in the control of diuresis, a process that includes mixing of the hemolymph. here, we show that a member of the insect calcitonin-like diuretic hormone (cldh) family is present in the american lobster, homarus americanus, serving, at least in part, as a powerful modulator of cardiac output. specifically, during an ongoing est project, a transcript encoding a putative h. americanus cldh precu ...	0	20008368
cd14 signaling restrains chronic inflammation through induction of p38-mapk/socs-dependent tolerance.	current thinking emphasizes the primacy of cd14 in facilitating recognition of microbes by certain tlrs to initiate pro-inflammatory signaling events and the importance of p38-mapk in augmenting such responses. herein, this paradigm is challenged by demonstrating that recognition of live borrelia burgdorferi not only triggers an inflammatory response in the absence of cd14, but one that is, in part, a consequence of altered pi3k/akt/p38-mapk signaling and impaired negative regulation of tlr2. cd ...	2009	20011115
elemol and amyris oil repel the ticks ixodes scapularis and amblyomma americanum (acari: ixodidae) in laboratory bioassays.	the essential oil from amyris balsamifera (rutaceae) and elemol, a principal constituent of the essential oil of osage orange, maclura pomifera (moraceae) were evaluated in in vitro and in vivo laboratory bioassays for repellent activity against host-seeking nymphs of the blacklegged tick, ixodes scapularis, and the lone star tick, amblyomma americanum. both bioassays took advantage of the tendency of these host-seeking ticks to climb slender vertical surfaces. in one bioassay, the central porti ...	2010	20016930
hunchback and ikaros-like zinc finger genes control reproductive system development in caenorhabditis elegans.	here we provide evidence for a c2h2 zinc finger gene family with similarity to ikaros and hunchback. the founding member of this family is caenorhabditis elegans ehn-3, which has important and poorly understood functions in somatic gonad development. we examined the expression and function of four additional hunchback/ikaros-like (hil) genes in c. elegans reproductive system development. two genes, ehn-3 and r08e3.4, are expressed in somatic gonadal precursors (sgps) and have overlapping functio ...	2010	20026024
genome sequence of the endosymbiont rickettsia peacockii and comparison with virulent rickettsia rickettsii: identification of virulence factors.	rickettsia peacockii, also known as the east side agent, is a non-pathogenic obligate intracellular bacterium found as an endosymbiont in dermacentor andersoni ticks in the western usa and canada. its presence in ticks is correlated with reduced prevalence of rickettsia rickettsii, the agent of rocky mountain spotted fever. it has been proposed that a virulent sfg rickettsia underwent changes to become the east side agent. we determined the genome sequence of r. peacockii and provide a compariso ...	2009	20027221
identification and molecular characterization of a cyclic-di-gmp effector protein, plza (bb0733): additional evidence for the existence of a functional cyclic-di-gmp regulatory network in the lyme disease spirochete, borrelia burgdorferi.	the borrelia burgdorferi rrp1 protein is a diguanylate cyclase that controls a regulon consisting of approximately 10% of the total genome. because rrp1 lacks a dna-binding domain, its regulatory capability is most likely mediated through the production of bis-(3'-5')-cyclic dimeric gmp (c-di-gmp). c-di-gmp binds to and activates the regulatory activity of proteins that harbor a pilz domain. the occurrence of a pilz domain within a protein is not in and of itself sufficient to convey c-di-gmp bi ...	2010	20030712
the borrelial fibronectin-binding protein reva is an early antigen of human lyme disease.	previous studies using small numbers of serum samples from human patients and experimentally infected animals identified the frequent presence of antibodies recognizing reva, a borrelial fibronectin-binding outer surface protein. we now demonstrate that most examined lyme disease spirochetes from north america and europe contain genes encoding reva proteins, some with extensive regions of conservation and others with moderate diversity. line blot analyses using recombinant reva from two diverse ...	2010	20032216
platelet aggregation inhibitors from hematophagous animals.	salivary glands from blood-sucking animals (e.g., mosquitoes, bugs, sand flies, fleas, ticks, leeches, hookworms, bats) are a rich source of bioactive molecules that counteract hemostasis in a redundant and synergistic manner. this review discusses recent progress in the identification of salivary inhibitors of platelet aggregation, their molecular characterization, and detailed mechanism of action. diversity of inhibitors is remarkable, with distinct families of proteins characterized as apyras ...	2009	20035779
seasonal population dynamics and behaviour of insects in models of vector-borne pathogens.		2004	20041037
rhipicephalus (boophilus) microplus: clotting time in tick-infested skin varies according to local inflammation and gene expression patterns in tick salivary glands.	ticks deposit saliva at the site of their attachment to a host in order to inhibit haemostasis, inflammation and innate and adaptive immune responses. the anti-haemostatic properties of tick saliva have been described by many studies, but few show that tick infestations or its anti-haemostatic components exert systemic effects in vivo. in the present study, we extended these observations and show that, compared with normal skin, bovine hosts that are genetically susceptible to tick infestations ...	2010	20045690
environmental health indicators of climate change for the united states: findings from the state environmental health indicator collaborative.	to develop public health adaptation strategies and to project the impacts of climate change on human health, indicators of vulnerability and preparedness along with accurate surveillance data on climate-sensitive health outcomes are needed. we researched and developed environmental health indicators for inputs into human health vulnerability assessments for climate change and to propose public health preventative actions.	2009	20049116
climate change, its impact on human health in the arctic and the public health response to threats of emerging infectious diseases.		2009	20052420
severe ehrlichia infection in pediatric oncology and stem cell transplant patients.	ehrlichiosis, a tickborne illness transmitted by tick vectors amblyomma americanum and ixodes scapularis, can be acquired in endemic areas. clinical manifestations range from asymptomatic to fulminant in nature. we report three cases of ehrlichiosis in pediatric oncology patients, one of whom was a stem cell transplant recipient. early symptoms included fever, malaise, and vague gastrointestinal symptoms. laboratory abnormalities were initially attributed to chemotherapy toxicity. illness was se ...	2010	20052776
the immunosuppresive tick salivary protein, salp15.	the interaction between ixodid ticks and their mammalian hosts is a complex relationship. while the mammalian host tries to avoid the completion of the feeding process, the tick has devised strategies to counteract these attempts. tick saliva contains a vast array of pharmacological activities that presumably aid the tick to evade host responses, including anticomplement, oxidative and innate and adaptive immune responses. the characterization of these activities has gained momentum in the last ...	2009	20054980
treatment of lyme borreliosis.	borrelia burgdorferi sensu lato is the causative agent of lyme borreliosis in humans. this inflammatory disease can affect the skin, the peripheral and central nervous system, the musculoskeletal and cardiovascular system and rarely the eyes. early stages are directly associated with viable bacteria at the site of inflammation. the pathogen-host interaction is complex and has been elucidated only in part. b. burgdorferi is highly susceptible to antibiotic treatment and the majority of patients p ...	2009	20067594
ability of two natural products, nootkatone and carvacrol, to suppress ixodes scapularis and amblyomma americanum (acari: ixodidae) in a lyme disease endemic area of new jersey.	we evaluated the ability of the natural, plant-derived acaricides nootkatone and carvacrol to suppress ixodes scapularis say and amblyomma americanum (l.) (acari: ixodidae). aqueous formulations of 1 and 5% nootkatone applied by backpack sprayer to the forest litter layer completely suppressed i. scapularis nymphs through 2 d. thereafter, the level of reduction gradually declined to < or =50% at 28 d postapplication. against a. americanum nymphs, 1% nootkatone was less effective, but at a 5% con ...	2009	20069863
experimental vaccination of sheep and cattle against tick infestation using recombinant 5'-nucleotidase.	limited prior evidence suggests that 5'-nucleotidase, an ectoenzyme principally located in the malpighian tubules of the tick rhipicephalus (boophilus) microplus, could be an effective antigen in an anti-tick vaccine. to assess this, recombinant 5'-nucleotidase was expressed in escherichia coli and used in vaccination trials with both sheep and cattle. vaccinated sheep were challenged with freshly moulted adult ticks. those with high titres of anti-nucleotidase antibodies showed significant prot ...	2010	20070827
functional genomics tool: gene silencing in ixodes scapularis eggs and nymphs by electroporated dsrna.	ticks are blood-sucking arthropods responsible for transmitting a wide variety of disease-causing agents, and constitute important public health threats globally. ixodes scapularis is the primary vector of the lyme disease agent in the eastern and central u.s. rnai is a mechanism by which gene-specific double-stranded rna (dsrna) triggers degradation of homologous mrna transcripts. here, we describe an optimized protocol for effectively suppressing gene expression in the egg and nymphal stages o ...	2010	20074328
a new view on lyme disease: rodents hold the key to annual risk.		2006	20076583
[ehrlichiosis/anaplasmosis].	ehrlichiosis and anaplasmosis are zoonoses caused by bacteria from the family anaplasmataceae, including human and animal pathogens. the human pathogens are ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis (hme), anaplasma phagocytophilum, the pathogen causing human granulocytic anaplasmosis (hga), e. ewingii and neorickettsia sennetsu, granulocytotropic and monocytotropic ehrlichia species, respectively. ehrlichia spp. are small, gram-negative, obligate intracellular b ...	2009	20077398
a vertebrate gene, ticrr, is an essential checkpoint and replication regulator.	eukaryotes have numerous checkpoint pathways to protect genome fidelity during normal cell division and in response to dna damage. through a screen for g2/m checkpoint regulators in zebrafish, we identified ticrr (for topbp1-interacting, checkpoint, and replication regulator), a previously uncharacterized gene that is required to prevent mitotic entry after treatment with ionizing radiation. ticrr deficiency is embryonic-lethal in the absence of exogenous dna damage because it is essential for n ...	2010	20080954
coinfection of western gray squirrel (sciurus griseus) and other sciurid rodents with borrelia burgdorferi sensu stricto and anaplasma phagocytophilum in california.	overlapping geographic distributions of tick-borne disease agents utilizing the same tick vectors are common, and coinfection of humans, domestic animals, wildlife, and ticks with both borrelia burgdorferi and anaplasma phagocytophilum has been frequently reported. this study was undertaken in order to evaluate the prevalence of both b. burgdorferi sensu stricto (hereinafter referred to as b. burgdorferi) and a. phagocytophilum in several species of sciurid rodents from northern california, usa. ...	2010	20090047
wide dispersal and possible multiple origins of low-copy-number plasmids in rickettsia species associated with blood-feeding arthropods.	plasmids are mobile genetic elements of bacteria that can impart important adaptive traits, such as increased virulence or antibiotic resistance. we report the existence of plasmids in rickettsia (rickettsiales; rickettsiaceae) species, including rickettsia akari, "candidatus rickettsia amblyommii," r. bellii, r. rhipicephali, and reis, the rickettsial endosymbiont of ixodes scapularis. all of the rickettsiae were isolated from humans or north and south american ticks. r. parkeri isolates from b ...	2010	20097813
tick burden on european roe deer (capreolus capreolus).	in our study we assessed the tick burden on roe deer (capreolus capreolus l.) in relation to age, physical condition, sex, deer density and season. the main objective was to find predictive parameters for tick burden. in september 2007, may, july, and september 2008, and in may and july 2009 we collected ticks on 142 culled roe deer from nine forest departments in southern hesse, germany. to correlate tick burden and deer density we estimated deer density using line transect sampling that accoun ...	2010	20099011
rickettsial ompb promoter regulated expression of gfpuv in transformed rickettsia montanensis.	rickettsia spp. (rickettsiales: rickettsiaceae) are gram-negative, obligate intracellular, alpha-proteobacteria that have historically been associated with blood-feeding arthropods. certain species cause typhus and spotted fevers in humans, but others are of uncertain pathogenicity or may be strict arthropod endosymbionts. genetic manipulation of rickettsiae should facilitate a better understanding of their interactions with hosts.	2010	20126457
the mdm2 and p53 genes are conserved in the arachnids.	the p53 protein and its negative regulator the ubiquitin e3 ligase mdm2 have been shown to be conserved from the t. adhaerens to man. in common with d. melanogaster and c. elegans, there is a single copy of the p53 gene in t. adhaerens, while in the vertebrates three p53-like genes can be found: p53, p63 and p73. the mdm2 gene is not present within the fully sequenced and highly annotated genomes of c. elegans and d. melanogaster. however, it is present in placazoanand the presence of multiple d ...	2010	20160485
insights into the venom composition of the ectoparasitoid wasp nasonia vitripennis from bioinformatic and proteomic studies.	with the nasonia vitripennis genome sequences available, we attempted to determine the proteins present in venom by two different approaches. first, we searched for the transcripts of venom proteins by a bioinformatic approach using amino acid sequences of known hymenopteran venom proteins. second, we performed proteomic analyses of crude n. vitripennis venom removed from the venom reservoir, implementing both an off-line two-dimensional liquid chromatography matrix-assisted laser desorption/ io ...	0	20167014
bba52 facilitates borrelia burgdorferi transmission from feeding ticks to murine hosts.	borrelia burgdorferi, the pathogen of lyme borreliosis, persists in nature through a tick-rodent transmission cycle. a selective assessment of the microbial transcriptome, limited to gene-encoding putative membrane proteins, reveals that bba52 transcription in vivo is strictly confined to the vector-specific portion of the microbial life cycle, with the highest levels of expression noted in feeding ticks and with swift down-regulation noted in mice. bba52 deletion did not affect murine disease a ...	2010	20170377
subolesin expression in response to pathogen infection in ticks.	ticks (acari: ixodidae) are vectors of pathogens worldwide that cause diseases in humans and animals. ticks and pathogens have co-evolved molecular mechanisms that contribute to their mutual development and survival. subolesin was discovered as a tick protective antigen and was subsequently shown to be similar in structure and function to akirins, an evolutionarily conserved group of proteins in insects and vertebrates that controls nf-kb-dependent and independent expression of innate immune res ...	2010	20170494
structural cuticular proteins from arthropods: annotation, nomenclature, and sequence characteristics in the genomics era.	the availability of whole genome sequences of several arthropods has provided new insights into structural cuticular proteins (cps), in particular the distribution of different families, the recognition that these proteins may comprise almost 2% of the protein coding genes of some species, and the identification of features that should aid in the annotation of new genomes and est libraries as they become available. twelve cp families are described: cpr (named after the rebers and riddiford conse ...	2010	20171281
lyme disease vaccine.		2000	20177519
arthropod-borne disease in canada: a clinician's perspective from the 'cold zone'.	arthropod-borne diseases do not occur commonly in canada. nevertheless, canadians run the risk of contracting certain infections within the country during arthropod season, as well as when travelling abroad. therefore, it is important that clinicians are aware of the possible occurrence of arthropod-borne diseases, and consider them in their differential diagnoses. the present review is divided into two sections: arthropod-borne diseases or disease agents documented in canada, and imported arthr ...	0	20177520
immunity and other defenses in pea aphids, acyrthosiphon pisum.	recent genomic analyses of arthropod defense mechanisms suggest conservation of key elements underlying responses to pathogens, parasites and stresses. at the center of pathogen-induced immune responses are signaling pathways triggered by the recognition of fungal, bacterial and viral signatures. these pathways result in the production of response molecules, such as antimicrobial peptides and lysozymes, which degrade or destroy invaders. using the recently sequenced genome of the pea aphid (acyr ...	2010	20178569
two immunoregulatory peptides with antioxidant activity from tick salivary glands.	ticks are blood-feeding arthropods that may secrete immunosuppressant molecules, which inhibit host inflammatory and immune responses and provide survival advantages to pathogens at tick bleeding sites in hosts. in the current work, two families of immunoregulatory peptides, hyalomin-a and -b, were first identified from salivary glands of hard tick hyalomma asiaticum asiaticum. three copies of hyalomin-a are encoded by an identical gene and released from the same protein precursor. both hyalomin ...	2010	20178988
expansion of the mirna pathway in the hemipteran insect acyrthosiphon pisum.	the pathways that allow short noncoding rnas such as the micrornas (mirnas) to mediate gene regulation and control critical cellular and developmental processes involve a limited number of key protein components. these proteins are the dicer-like rnases, double-stranded rna (dsrna)-binding proteins, and the argonaute (ago) proteins that process stem-loop hairpin transcripts of endogenous genes to generate mirnas or long dsrna precursors (either exogenous or endogenous). comparative genomics stud ...	2010	20179251
extraction of total nucleic acids from ticks for the detection of bacterial and viral pathogens.	ticks harbor numerous bacterial, protozoal, and viral pathogens that can cause serious infections in humans and domestic animals. active surveillance of the tick vector can provide insight into the frequency and distribution of important pathogens in the environment. nucleic-acid based detection of tick-borne bacterial, protozoan, and viral pathogens requires the extraction of both dna and rna (total nucleic acids) from ticks. traditional methods for nucleic acid extraction are limited to extrac ...	2010	20180313
molecular evolution of the crustacean hyperglycemic hormone family in ecdysozoans.	crustacean hyperglycemic hormone (chh) family peptides are neurohormones known to regulate several important functions in decapod crustaceans such as ionic and energetic metabolism, molting and reproduction. the structural conservation of these peptides, together with the variety of functions they display, led us to investigate their evolutionary history. chh family peptides exist in insects (ion transport peptides) and may be present in all ecdysozoans as well. in order to extend the evolutiona ...	2010	20184761
a 60-year meta-analysis of tick paralysis in the united states: a predictable, preventable, and often misdiagnosed poisoning.	tick paralysis (tp) is a neurotoxic poisoning primarily afflicting young girls in endemic regions. recent case series of tp have described increasing misdiagnoses of tp as the guillain-barré syndrome (gbs). a meta-analysis of the scientific literature was conducted using internet search engines to assess the evolving epidemiology of tp. fifty well-documented cases of tp were analyzed over the period 1946-2006. cases were stratified by demographics, clinical manifestations, and outcomes. misdiagn ...	2010	20186584
identification of residues within ligand-binding domain 1 (lbd1) of the borrelia burgdorferi ospc protein required for function in the mammalian environment.	borrelia burgdorferi outer surface protein c (ospc) is required for the establishment of infection in mammals. however, its precise function remains controversial. the biologically active form of ospc appears to be a homodimer. alpha helix 1 and 1' of the apposing monomers form a solvent-accessible pocket at the dimeric interface that presents a putative ligand-binding domain (lbd1). here we employ site-directed and allelic-exchange mutagenesis to test the hypothesis that lbd1 is a determinant o ...	2010	20199597
two novel salp15-like immunosuppressant genes from salivary glands of ixodes persulcatus schulze tick.	salp15, a 15-kda tick salivary gland protein, is known for several suppressive activities against host immunity and critical functions for the transmission of lyme borrelia in ixodes scapularis and ixodes ricinus, the major vectors found in north america and western europe. salp15 inhibits the activation of cluster of differentiation (cd)4(+)t-cells through the repression of t-cell receptor (tcr)-triggered calcium fluxes and interleukin (il)-2 production. furthermore, salp15 adheres to the spiro ...	2010	20201978
bartonella spp. transmission by ticks not established.	bartonella spp. infect humans and many animal species. mainly because pcr studies have demonstrated bartonella dna in ticks, some healthcare providers believe that these microorganisms are transmitted by ticks. b. henselae, in particular, is regarded as being present in and transmissible by the ixodes scapularis tick. the presence of a microbial agent within a tick, however, does not imply that the tick might transmit it during the course of blood feeding and does not confer epidemiologic import ...	2010	20202410
potential for tick-borne bartonelloses.	as worldwide vectors of human infectious diseases, ticks are considered to be second only to mosquitoes. each tick species has preferred environmental conditions and biotopes that determine its geographic distribution, the pathogens it vectors, and the areas that pose risk for tick-borne diseases. researchers have identified an increasing number of bacterial pathogens that are transmitted by ticks, including anaplasma, borrelia, ehrlichia, and rickettsia spp. recent reports involving humans and ...	2010	20202411
borrelia, ehrlichia, and rickettsia spp. in ticks removed from persons, texas, usa.	data regarding the type, frequency, and distribution of tick-borne pathogens and bacterial agents are not widely available for many tick species that parasitize persons in the southern united states. we therefore analyzed the frequency and identity of pathogens and bacterial agents in ticks removed from humans and subsequently submitted to the texas department of state health services, zoonosis control program, from october 1, 2004, through september 30, 2008. the data showed associations of bac ...	2010	20202419
using the dfci gene index databases for biological discovery.	the dfci gene index web pages provide access to analyses of ests and gene sequences for nearly 114 species, as well as a number of resources derived from these. each species-specific database is presented using a common format with a home page. a variety of methods exist that allow users to search each species-specific database. methods implemented currently include nucleotide or protein sequence queries using wu-blast, text-based searches using various sequence identifiers, searches by gene, ti ...	0	20205187
meeting the challenges of on-host and off-host water balance in blood-feeding arthropods.	in this review, we describe water balance requirements of blood-feeding arthropods, particularly contrasting dehydration tolerance during the unfed, off-host state and the challenges of excess water that accompany receipt of the bloodmeal. most basic water balance characteristics during the off-host stage are applicable to other terrestrial arthropods, as well. a well-coordinated suite of responses enable arthropods to conserve water resources, enhance their desiccation tolerance, and increase t ...	2010	20206630
anaplasma phagocytophilum aph_1387 is expressed throughout bacterial intracellular development and localizes to the pathogen-occupied vacuolar membrane.	obligate vacuolar pathogens produce proteins that localize to the host cell-derived membranes of the vacuoles in which they reside, yielding unique organelles that are optimally suited for pathogen survival. anaplasma phagocytophilum is an obligate vacuolar bacterium that infects neutrophils and causes the emerging and potentially fatal disease human granulocytic anaplasmosis. here we identified aph_1387 as the first a. phagocytophilum-derived protein that associates with the a. phagocytophilum- ...	2010	20212090
silencing of three amblyomma americanum (l.) insulin-like growth factor binding protein-related proteins prevents ticks from feeding to repletion.	the insulin-like growth factor (igf) binding proteins (igfbp) family is the regulatory arm of the igf signaling system that control mitogenic and anabolic actions of igf peptide hormones. this study describes cloning and biological characterization of three amblyomma americanum (l.) (aam) proteins that show amino-terminal sequence and secondary structure similarity to the igfbp superfamily. the three molecules here provisionally identified as aamigfbp-rp1 and short (s) and long (l) aamigfbp-rp6 ...	2010	20228352
invasion of the lyme disease vector ixodes scapularis: implications for borrelia burgdorferi endemicity.	lyme disease risk is increasing in the united states due in part to the spread of blacklegged ticks ixodes scapularis, the principal vector of the spirochetal pathogen borrelia burgdorferi. a 5-year study was undertaken to investigate hypothesized coinvasion of i. scapularis and b. burgdorferi in lower michigan. we tracked the spatial and temporal dynamics of the tick and spirochete using mammal, bird, and vegetation drag sampling at eight field sites along coastal and inland transects originati ...	2010	20229127
use of the cre-lox recombination system to investigate the lp54 gene requirement in the infectious cycle of borrelia burgdorferi.	borrelia burgdorferi, the causative agent of lyme disease, has a complex genome consisting of a linear chromosome and up to 21 linear and circular plasmids. these plasmids encode numerous proteins critical to the spirochete's infectious cycle and many hypothetical proteins whose functions and requirements are unknown. the conserved linear plasmid lp54 encodes several proteins important for survival in the mouse-tick infectious cycle, but the majority of the proteins are of unknown function and l ...	2010	20231410
one-year duration of immunity induced by vaccination with a canine lyme disease bacterin.	laboratory-reared beagles were vaccinated with a placebo or a bacterin comprised of borrelia burgdorferi s-1-10 and ospa-negative/ospb-negative b. burgdorferi 50772 and challenged after 1 year with b. burgdorferi-infected ixodes scapularis ticks. for the placebo recipients, spirochetes were recovered from 9 (60%) skin biopsy specimens collected after 1 month, and the organisms persisted in the skin thereafter. ten (67%) dogs also developed joint infection (3 dogs), lameness or synovitis (7 dogs) ...	2010	20237200
differential expression of genes in salivary glands of male rhipicephalus (boophilus)microplus in response to infection with anaplasma marginale.	bovine anaplasmosis, caused by the rickettsial tick-borne pathogen anaplasma marginale (rickettsiales: anaplasmataceae), is vectored by rhipicephalus (boophilus)microplus in many tropical and subtropical regions of the world. a. marginale undergoes a complex developmental cycle in ticks which results in infection of salivary glands from where the pathogen is transmitted to cattle. in previous studies, we reported modification of gene expression in dermacentor variabilis and cultured ixodes scapu ...	2010	20298599
sequences essential for transmission of spiroplasma citri by its leafhopper vector, circulifer haematoceps, revealed by plasmid curing and replacement based on incompatibility.	spiroplasma citri gii3 contains highly related low-copy-number plasmids psci1 to -6. despite the strong similarities between their replication regions, these plasmids coexist in the spiroplasma cells, indicating that they are mutually compatible. the psci1 to -6 plasmids encode the membrane proteins known as s. citri adhesion-related proteins (scarps) (psci1 to -5) and the hydrophilic protein p32 (psci6), which had been tentatively associated with insect transmission, as they were not detected i ...	2010	20305023
borrelia carolinensis sp. nov., a novel species of the borrelia burgdorferi sensu lato complex isolated from rodents and a tick from the south-eastern usa.	a group of 16 isolates with genotypic characteristics different from those of known species of the borrelia burgdorferi sensu lato complex were cultured from ear biopsies of the rodents peromyscus gossypinus and neotoma floridana trapped at five localities in south carolina, usa, and from the tick ixodes minor feeding on n. floridana. multilocus sequence analysis of members of the novel species, involving the 16s rrna gene, the 5s-23s (rrf-rrl) intergenic spacer region and the flagellin, ospa an ...	2011	20305062
genome organization of major tandem repeats in the hard tick, ixodes scapularis.	in spite of the global medical and veterinary importance of ixodid ticks, relatively little is known about their genome organization. to address this, we developed the first fluorescence in situ hybridization (fish)-based chromosome markers in the lyme disease vector, ixodes scapularis. shotgun genomic dna (gdna) sequences were used to identify three major tandem repeat families which were localized to specific heterochromatic regions of i. scapularis chromosomes prepared from the mitotic cell l ...	2010	20306126
phagocytosis of the lyme disease spirochete, borrelia burgdorferi, by cells from the ticks, ixodes scapularis and dermacentor andersoni, infected with an endosymbiont, rickettsia peacockii.	tick cell lines were used to model the effects of endosymbiont infection on phagocytic immune responses. the lines tested for their ability to phagocytose the lyme disease spirochete, borrelia burgdorferi (spirochaetales: spirochaetaceae), were ise6 and ide12 from the black-legged tick, ixodes scapularis say (acari: ixodidae) and dae15 from the rocky mountain wood tick, dermacentor andersoni stiles. rickettsia peacockii (rickettsiales: rickettsiaceae), an endosymbiont of d. andersoni, was used a ...	2007	20331397
fucosylation enhances colonization of ticks by anaplasma phagocytophilum.	fucosylated structures participate in a wide range of pathological processes in eukaryotes and prokaryotes. the impact of fucose on microbial pathogenesis, however, has been less appreciated in arthropods of medical relevance. thus, we used the tick-borne bacterium anaplasma phagocytophilum- the agent of human granulocytic anaplasmosis to understand these processes. here we show that a. phagocytophilum uses alpha1,3-fucose to colonize ticks. we demonstrate that a. phagocytophilum modulates the e ...	2010	20331643
identification of a tsetse fly salivary protein with dual inhibitory action on human platelet aggregation.	tsetse flies (glossina sp.), the african trypanosome vectors, rely on anti-hemostatic compounds for efficient blood feeding. despite their medical importance, very few salivary proteins have been characterized and functionally annotated.	2010	20351782
cloning and characterisation of schistosoma japonicum insulin receptors.	schistosomes depend for growth and development on host hormonal signals, which may include the insulin signalling pathway. we cloned and assessed the function of two insulin receptors from schistosoma japonicum in order to shed light on their role in schistosome biology.	2010	20352052
horizontal and vertical movements of host-seeking ixodes pacificus (acari: ixodidae) nymphs in a hardwood forest.	the nymph of the western black-legged tick (ixodes pacificus) is an important bridging vector of the lyme disease spirochete (borrelia burgdorferi) to humans in the far-western united states. the previously unknown dispersal capabilities of this life stage were studied in relation to logs, tree trunks, and adjacent leaf-litter areas in a mixed hardwood forest using mark-release-recapture methods. in two spatially and temporally well-spaced trials involving logs, the estimated mean distances that ...	2009	20352083
an insight into the sialome of glossina morsitans morsitans.	blood feeding evolved independently in worms, arthropods and mammals. among the adaptations to this peculiar diet, these animals developed an armament of salivary molecules that disarm their host's anti-bleeding defenses (hemostasis), inflammatory and immune reactions. recent sialotranscriptome analyses (from the greek sialo = saliva) of blood feeding insects and ticks have revealed that the saliva contains hundreds of polypeptides, many unique to their genus or family. adult tsetse flies feed e ...	2010	20353571
novel technique for quantifying adhesion of metarhizium anisopliae conidia to the tick cuticle.	the present study describes an accurate quantitative method for quantifying the adherence of conidia to the arthropod cuticle and the dynamics of conidial germination on the host. the method was developed using conidia of metarhizium anisopliae var. anisopliae (metschn.) sorokin (hypocreales: clavicipitaceae) and engorged rhipicephalus annulatus (say) (arachnida: ixodidae) females and was also verified for m. anisopliae var. acridum driver et milner (hypocreales: clavicipitaceae) and alphitobius ...	2010	20363785
the bba64 gene of borrelia burgdorferi, the lyme disease agent, is critical for mammalian infection via tick bite transmission.	the spirochetal agent of lyme disease, borrelia burgdorferi, is transmitted by bites of ixodes ticks to mammalian reservoir hosts and humans. the mechanism(s) by which the organism is trafficked from vector to host is poorly understood. in this study, we demonstrate that a b. burgdorferi mutant strain deficient in the synthesis of the bba64 gene product was incapable of infecting mice via tick bite even though the mutant was (i) infectious in mice when introduced by needle inoculation, (ii) acqu ...	2010	20368453
the alveolate perkinsus marinus: biological insights from est gene discovery.	perkinsus marinus, a protozoan parasite of the eastern oyster crassostrea virginica, has devastated natural and farmed oyster populations along the atlantic and gulf coasts of the united states. it is classified as a member of the perkinsozoa, a recently established phylum considered close to the ancestor of ciliates, dinoflagellates, and apicomplexans, and a key taxon for understanding unique adaptations (e.g. parasitism) within the alveolata. despite intense parasite pressure, no disease-resis ...	2010	20374649
emergence of zoonotic arboviruses by animal trade and migration.	abstract: arboviruses are transmitted in nature exclusively or to a major extend by arthropods. they belong to the most important viruses invading new areas in the world and their occurrence is strongly influenced by climatic changes due to the life cycle of the transmitting vectors. several arboviruses have emerged in new regions of the world during the last years, like west nile virus (wnv) in the americas, usutu virus (usuv) in central europe, or rift valley fever virus (rvfv) in the arabian ...	2010	20377873
community ecology and disease risk: lizards, squirrels, and the lyme disease spirochete in california, usa.	vector-borne zoonotic diseases are often maintained in complex transmission cycles involving multiple vertebrate hosts and their arthropod vectors. in the state of california, u.s.a., the spirochete borrelia burgdorferi, which causes lyme disease, is transmitted between vertebrate hosts by the western black-legged tick, ixodes pacificus. several mammalian species serve as reservoir hosts of the spirochete, but levels of tick infestation, reservoir competence, and borrelia-infection prevalence va ...	2010	20380218
coxiella burnetii in humans and ticks in rural senegal.	q fever is a worldwide zoonotic disease caused by coxiella burnetii. epidemiologically, animals are considered reservoirs and humans incidental hosts.	2010	20386603
cold storage and cryopreservation of tick cell lines.	abstract:	2010	20388200
uncoordinated phylogeography of borrelia burgdorferi and its tick vector, ixodes scapularis.	vector-borne microbes necessarily co-occur with their hosts and vectors, but the degree to which they share common evolutionary or biogeographic histories remains unexplored. we examine the congruity of the evolutionary and biogeographic histories of the bacterium and vector of the lyme disease system, the most prevalent vector-borne disease in north america. in the eastern and midwestern us, ixodes scapularis ticks are the primary vectors of borrelia burgdorferi, the bacterium that causes lyme ...	2010	20394659
translocation of borrelia burgdorferi surface lipoprotein ospa through the outer membrane requires an unfolded conformation and can initiate at the c-terminus.	borrelia burgdorferi surface lipoproteins are essential to the pathogenesis of lyme borreliosis, but the mechanisms responsible for their localization are only beginning to emerge. we have previously demonstrated the critical nature of the amino-terminal 'tether' domain of the mature lipoprotein for sorting a fluorescent reporter to the borrelia cell surface. here, we show that individual deletion of four contiguous residues within the tether of major surface lipoprotein ospa results in its inef ...	2010	20398211
identification of two small heat shock proteins with different response profile to cadmium and pathogen stresses in venerupis philippinarum.	small heat shock proteins (shsps) encompass a widespread and diverse class of proteins with molecular chaperone activity. in the present study, two shsp isoforms (vpshsp-1 and vpshsp-2) were cloned from venerupis philippinarum haemocytes by rapid amplification of cdna ends (race) approaches. the expression profiles of these two genes under vibrio anguillarum challenge and cadmium exposure were investigated by quantitative real-time reverse transcriptase polymerase chain reaction. the bacterial c ...	2010	20405260
rapid identification of vector-borne flaviviruses by mass spectrometry.	flaviviruses are a highly diverse group of rna viruses classified within the genus flavivirus, family flaviviridae. most flaviviruses are arthropod-borne, requiring a mosquito or tick vector. several flaviviruses are highly pathogenic to humans; however, their high genetic diversity and immunological relatedness makes them extremely challenging to diagnose. in this study, we developed and evaluated a broad-range flavivirus assay designed to detect both tick- and mosquito-borne flaviviruses by us ...	2010	20412852
an invertebrate mdm homolog interacts with p53 and is differentially expressed together with p53 and ras in neoplastic mytilus trossulus haemocytes.	the mussel mytilus trossulus can develop a neoplasia of the haemolymph, which occurs with high frequency (up to 40%) in nature. associated with this disease are pro-apoptotic tumor-suppressor protein p53 isoforms, which are highly conserved between molluscs and vertebrates. the vertebrate wildtype p53 protein is maintained at low levels by the mdm2 protein in non-stressed cells to prevent undesired apoptosis. identification of a putative invertebrate mdm-like homolog suggests early evolution of ...	2010	20417299
active and passive surveillance and phylogenetic analysis of borrelia burgdorferi elucidate the process of lyme disease risk emergence in canada.	northward expansion of the tick ixodes scapularis is driving lyme disease (ld) emergence in canada. information on mechanisms involved is needed to enhance surveillance and identify where ld risk is emerging.	2010	20421192
role of the surface lipoprotein bba07 in the enzootic cycle of borrelia burgdorferi.	borrelia burgdorferi, the lyme disease pathogen, dramatically alters its protein profile when it is transmitted between ticks and mammals. several differentially expressed proteins have been shown to be critical for the enzootic cycle of b. burgdorferi. in this study, we demonstrated that expression of the surface lipoprotein-encoding gene bba07 is induced by an elevated temperature and a reduced ph during in vitro cultivation, as well as during nymphal tick feeding. expression of bba07 is regul ...	2010	20421380
lyme disease: a review.	lyme disease is the most common vector-borne illness in the united states and is also endemic in europe and asia. it is caused by the spirochete borrelia burgdorferi and transmitted by the bite of the ixodes (deer) tick. it occurs most frequently during spring and summer and may involve the skin, nervous system, heart, and joints. this article reviews the pathogenesis, epidemiology, clinical manifestations, diagnosis, treatment, and prevention of lyme disease.	2010	20425509
the novel membrane protein tmem59 modulates complex glycosylation, cell surface expression, and secretion of the amyloid precursor protein.	ectodomain shedding of the amyloid precursor protein (app) by the two proteases alpha- and beta-secretase is a key regulatory event in the generation of the alzheimer disease amyloid beta peptide (abeta). at present, little is known about the cellular mechanisms that control app shedding and abeta generation. here, we identified a novel protein, transmembrane protein 59 (tmem59), as a new modulator of app shedding. tmem59 was found to be a ubiquitously expressed, golgi-localized protein. tmem59 ...	2010	20427278
gene up-regulation in response to predator kairomones in the water flea, daphnia pulex.	numerous cases of predator-induced polyphenisms, in which alternate phenotypes are produced in response to extrinsic stimuli, have been reported in aquatic taxa to date. the genus daphnia (branchiopoda, cladocera) provides a model experimental system for the study of the developmental mechanisms and evolutionary processes associated with predator-induced polyphenisms. in d. pulex, juveniles form neckteeth in response to predatory kairomones released by chaoborus larvae (insecta, diptera).	2010	20433737
homogeneity of powassan virus populations in naturally infected ixodes scapularis.	powassan virus (powv, flaviviridae: flavivirus) is the sole north american member of the tick-borne encephalitis complex and consists of two distinct lineages that are maintained in ecologically discrete enzootic transmission cycles. the underlying genetic mechanisms that lead to niche partitioning in arboviruses are poorly understood. therefore, intra- and interhost genetic diversity was analyzed to determine if powv exists as a quasispecies in nature and quantify selective pressures within and ...	2010	20434750
functional characterization of a phospholipase a(2) homolog from rickettsia typhi.	phospholipase a(2) (pla(2)) has long been proposed to be involved in rickettsial entry into host cells, escape from the phagosome to evade destruction by lysosomal exposure, and lysis of the host cells. however, the corresponding rickettsial gene(s) encoding a protein with pla(2) activity has not been identified or functionally characterized. here, we report that the rickettsia typhi genome possesses two genes encoding patatin-like pla(2) proteins, rt0590 and rt0522. sequence analysis of rt0522 ...	2010	20435729
identification of anaplasma marginale proteins specifically upregulated during colonization of the tick vector.	the transition between infection of the mammalian host and colonization of an arthropod vector is required for the ongoing transmission of a broad array of pathogens, from viruses to protozoa. understanding how this transition is mediated provides opportunities to disrupt transmission through either chemotherapy or immunization. we used an unbiased proteomic screen to identify anaplasma marginale proteins specifically upregulated in the tick compared to the mammalian host. comparative mass spect ...	2010	20439479
analysis of a borrelia burgdorferi phosphodiesterase demonstrates a role for cyclic-di-guanosine monophosphate in motility and virulence.	the genome of borrelia burgdorferi encodes a set of genes putatively involved in cyclic-dimeric guanosine monophosphate (cyclic-di-gmp) metabolism. although bb0419 was shown to be a diguanylate cyclase, the extent to which bb0419 or any of the putative cyclic-di-gmp metabolizing genes impact b. burgdorferi motility and pathogenesis has not yet been reported. here we identify and characterize a phosphodiesterase (bb0363). bb0363 specifically hydrolyzed cyclic-di-gmp with a k(m) of 0.054 microm, c ...	2010	20444101
pd-1 on immature and pd-1 ligands on migratory human langerhans cells regulate antigen-presenting cell activity.	langerhans cells (lcs) are known as "sentinels" of the immune system that function as professional antigen-presenting cells (apcs) after migration to draining lymph node. lcs are proposed to have a role in tolerance and the resolution of cutaneous immune responses. the programmed death-1 (pd-1) receptor and its ligands, pd-l1 and pd-l2, are a co-inhibitory pathway that contributes to the negative regulation of t-lymphocyte activation and peripheral tolerance. surprisingly, we found pd-1 to be ex ...	2010	20445553
bacterial pathogens in ixodid ticks from a piedmont county in north carolina: prevalence of rickettsial organisms.	in north carolina, reported human cases of tick-borne illness, specifically rocky mountain spotted fever, have escalated over the past decade. to determine the relative abundance of vectors and to estimate the risk of acquiring a tick-borne illness in peri-residential landscapes, ticks were collected in chatham county, a typical piedmont county and, samples of the ticks were tested for infection with selected bacterial pathogens using real-time quantitative polymerase chain reaction assays. tick ...	2010	20455778
phantom, a new subclass of mutator dna transposons found in insect viruses and widely distributed in animals.	transposons of the mutator (mu) superfamily have been shown to play a critical role in the evolution of plant genomes. however, the identification of mutator transposons in other eukaryotes has been quite limited. here we describe a previously uncharacterized group of dna transposons designated phantom identified in the genomes of a wide range of eukaryotic taxa, including many animals, and provide evidence for its inclusion within the mutator superfamily. interestingly three phantom proteins we ...	2010	20457878
evolution of a genomic regulatory domain: the role of gene co-option and gene duplication in the enhancer of split complex.	the drosophila enhancer of split complex [e(spl)-c] is a remarkable complex of genes many of which are effectors or modulators of notch signaling. the complex contains different classes of genes including four bearded genes and seven basic helix-loop-helix (bhlh) genes. we examined the evolution of this unusual complex by identifying bearded and bhlh genes in the genome sequences of arthropods. we find that a four-gene e(spl)-c, containing three bhlh genes and one bearded gene, is an ancient com ...	2010	20458100
massively parallel pyrosequencing-based transcriptome analyses of small brown planthopper (laodelphax striatellus), a vector insect transmitting rice stripe virus (rsv).	the small brown planthopper (laodelphax striatellus) is an important agricultural pest that not only damages rice plants by sap-sucking, but also acts as a vector that transmits rice stripe virus (rsv), which can cause even more serious yield loss. despite being a model organism for studying entomology, population biology, plant protection, molecular interactions among plants, viruses and insects, only a few genomic sequences are available for this species. to investigate its transcriptome and d ...	2010	20462456
detection of anaplasma marginale and a. phagocytophilum in bovine peripheral blood samples by duplex real-time reverse transcriptase pcr assay.	insufficient diagnostic sensitivity and specificity coupled with the potential for cross-reactivity among closely related anaplasma species has made the accurate determination of infection status problematic. a method for the development of simplex and duplex real-time quantitative reverse transcriptase pcr (qrt-pcr) assays for the detection of a. marginale and a. phagocytophilum 16s rrna in plasma-free bovine peripheral blood samples is described. the duplex assay was able to detect as few as 1 ...	2010	20463162
host associations of dermacentor, amblyomma, and ixodes (acari: ixodidae) ticks in tennessee.	from april 2007 to september 2008, 1,793 adult and nymphal ixodid ticks were collected from 49 counties in tennessee. six species were identified, including dermacentor variabilis (say), amblyomma americanum (l.), ixodes texanus (banks), ixodes cookei packard, ixodes scapularis (say), and amblyomma maculatum koch, from 13 medium- to large-sized mammalian hosts and dragging through vegetation. raccoons were the most common vertebrate source (198 captures), accounting for 60% of ticks collected. d ...	2010	20496589
forest and surface water as predictors of borrelia burgdorferi and its vector ixodes scapularis (acari: ixodidae) in indiana.	the objective of this study was to assess whether the distribution of borrelia burgdorferi, the causative agent of lyme disease, and its vector tick ixodes scapularis say (acari: ixodidae) across indiana is influenced by large-scale landscape features, specifically the proportion of forest within the surrounding landscape and the distance to water features such as lakes and major streams. hunter-killed deer were checked for ticks in designated check-stations in the opening firearm hunting season ...	2010	20496594
genotypic variation and mixtures of lyme borrelia in ixodes ticks from north america and europe.	lyme disease, caused by various species of borrelia, is transmitted by ixodes ticks in north america and europe. studies have shown the genotype of borrelia burgdorferi sensu stricto (s.s.) or the species of b. burgdorferi sensu lato (s.l.) affects the ability of the bacteria to cause local or disseminated infection in humans.	2010	20498837