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Male accessory gland molecules inhibit harmonic convergence in the mosquito Aedes aegypti.

Aedes aegypti mosquitoes transmit pathogens such as yellow fever, dengue, Zika, and chikungunya viruses to millions of human hosts annually [1]. As such, understanding Ae. aegypti courtship and mating biology could prove crucial to the success of disease control efforts that target reproduction. Potentially to communicate reproductive fitness [2,3], mosquito males and females harmonize their flight tones prior to mating in a behavior known as harmonic convergence (HC) [4]. Furthermore, after mating or treatment with extracts from male accessory glands (MAG), which make seminal fluid molecules,…

Discovery of an Aedes (Stegomyia) albopictus population and first records of Aedes (Stegomyia) aegypti in Canada.

A population of Aedes (Stegomyia) albopictus (Skuse) (Diptera: Culicidae), a vector of chikungunya, dengue, yellow fever, and Zika and West Nile viruses, has been detected in Windsor, Ontario, Canada from 2016 onwards. Here, we describe its seasonal distribution, as well as the various aquatic habitats from which this species was collected and its larval co-habitation. We collected immatures from tires, treeholes, extruded polystyrene foam containers, discarded plastic cups, old recycling bins and oviposition traps. Aedes albopictus larvae were collected with Aedes japonicus (Theobald), Anophe…

Aedes vector-host olfactory interactions in sylvatic and domestic dengue transmission environments.

Interactions between Aedes (Stegomyia) species and non-human primate (NHP) and human hosts govern the transmission of the pathogens, dengue, zika, yellow fever and chikungunya viruses. Little is known about Aedes mosquito olfactory interactions with these hosts in the domestic and sylvatic cycles where these viruses circulate. Here, we explore how the different host-derived skin odours influence Aedes mosquito responses in these two environments. In field assays, we show that the cyclic ketone cyclohexanone is a signature cue for Aedes mosquitoes to detect the NHP baboon, sykes and vervet, whe…

Mechanisms of transport of H+, Na+ and K+, across the distal gastric caecum of larval Aedes aegypti.

Measured changes in ion fluxes, transepithelial potential (TEP) and basolateral membrane potential (Vb) in response to ion transporter inhibitors were used to assess the mechanisms of transport of H+, Na+ and K+, across the distal gastric caecum of larval Aedes aegypti, a vector of yellow fever. Preparations were stimulated with 5-hydroxytryptamine (5-HT, 10-6 M) in order to maintain stable rates of H+, Na+, and K+ transport across the distal caecum. Transepithelial potential (TEP), basolateral membrane potential (Vb), and H+, Na+ and K+ fluxes all declined after the addition of a vacuolar-typ…

Flavivirus Cross-Reactivity to Dengue Nonstructural Protein 1 Antigen Detection Assays.

Dengue virus (DENV) and Zika virus (ZIKV) are flaviviruses of public health relevance. Both viruses circulate in the same endemic settings a … viviruses. Our results showed that substantially high viral titres of ZIKV, Kunjin virus (KUNV) and yellow fever virus (YFV) are required to give false-positive results when using DENV NS1 rapid detection assays. Commercial DENV NS1 ELISAs did not react with ZIKV and YFV. In comparison, tested assays detected DENV at a significantly low virus titre. Given the …

Development and evaluation of a novel high-throughput image-based fluorescent neutralization test for detection of Zika virus infection.

Zika virus (ZIKV) is an emerging arbovirus belonging to the genus flavivirus that comprises other important public health viruses, such as dengue (DENV) and yellow fever (YFV). In general, ZIKV infection is a self-limiting disease, however cases of Guillain-Barré syndrome and congenital brain abnormalities in newborn infants have been reported. Diagnosing ZIKV infection remains a challenge, as viral RNA detection is only applicable until a few days after the onset of symptoms. After that, serological tests must be applied, and, as expected, high cross-reactivity between ZIKV and other flavivir…

High-throughput neutralization assay for multiple flaviviruses based on single-round infectious particles using dengue virus type 1 reporter replicon.

Diseases caused by the genus Flavivirus, including dengue virus (DENV) and Zika virus (ZIKV), have a serious impact on public health worldwi … rane and envelope (prME) proteins from DENV1-4, ZIKV, Japanese encephalitis virus, West Nile virus, yellow fever virus, Usutu virus, and tick-borne encephalitis virus, along with a plasmid carrying DENV1 replicon containing the luciferase gene and plasmid for expression of DENV1 capsid. Luciferase activity of SRIPs-infected cells was well correlated with numbe …

Targeted reconstruction of T cell receptor sequence from single cell RNA-seq links CDR3 length to T cell differentiation state.

The T cell compartment must contain diversity in both T cell receptor (TCR) repertoire and cell state to provide effective immunity against … hes. Coupling TRAPeS with transcriptome analysis of CD8+ T cells specific for a single epitope from Yellow Fever Virus (YFV), we show that the recently described 'naive-like' memory population have significantly longer CDR3 regions and greater divergence from germline sequence than do effector-memory phenotype cells. This suggests that TCR usage is associated …

Enrichment of Viral Nucleic Acids by Solution Hybrid Selection with Genus Specific Oligonucleotides.

Despite recent advances, our knowledge of potential and rare human pathogens is far from exhaustive. Current molecular diagnostic tools main … on with genus-specific degenerate biotinylated oligonucleotides. Nucleic acids of the test viruses (yellow fever virus and Japanese encephalitis virus) were enriched by solution hybrid selection using pan-flavivirus oligonucleotides. Moreover, enterovirus (family: Picornaviridae, genus: Enterovirus) sequences were successfully enriched using foot-and-mouth dis …

Москито индицидальная активность листьев спондиас мамбин Л. против Aedes aegypti L. и изоляция активных принципов.

Aedes aegypti — домашний комарь и один из основных переносчиков денге и желтой лихорадки. Поскольку она является вектором смертельных заболеваний, ее борьба становится крайне важной. Лекарственные растения могут быть альтернативой индицидным агентам, поскольку они содержат богатый источник биоактивных соединений. Цель этого исследования состояла в том, чтобы определить индицидную активность метанола из спондиасских мамбинов, н-гексана, дихлорметана и этиловых ацетатовых фракций в отношении взрослых женщин Аэ. агипти комаров и выделить активное(ые) соединение(а), ответственное(ые) за биоактивно

Совпадение в аннотации оригинала
BACKGROUND & OBJECTIVES: Aedes aegypti is a domestic mosquito and one of the primary vectors for dengue and yellow fever. Since, it is a vector of deadly diseases, its control becomes essential. Medicinal plants may be an alternative to adulticidal agents since they contain rich source of bioactive compounds. This study was designed to determine the adultici…

Efficacy of the broad-spectrum antiviral compound BCX4430 against Zika virus in cell culture and in a mouse model.

Zika virus (ZIKV) is currently undergoing pandemic emergence. While disease is typically subclinical, severe neurologic manifestations in fetuses and newborns after congenital infection underscore an urgent need for antiviral interventions. The adenosine analog BCX4430 has broad-spectrum activity against a wide range of RNA viruses, including potent in vivo activity against yellow fever, Marburg and Ebola viruses. We tested this compound against African and Asian lineage ZIKV in cytopathic effect inhibition and virus yield reduction assays in various cell lines. To further evaluate the efficac…

Surveillance of mosquito-borne infectious diseases in febrile travelers entering China via Shenzhen ports, China, 2013.

BACKGROUND: About 100 million passengers enter China via Shenzhen ports every year and such huge populations increase the risk of various in … borne pathogens: Dengue virus (DENV), Japanese encephalitis virus (JEV), Chikungunya virus (CHIKV), yellow fever virus (YFV), and West Nile Virus (WNV). Additionally, malaria was diagnosed by rapid diagnostic tests (RDTs). RESULTS: In total, 34 cases were detected of DENV infection (serotype I to IV), 17 cases of JEV infection, 2 cases of CHIKV infection, and …

Chitosan/interfering RNA nanoparticle mediated gene silencing in disease vector mosquito larvae.

Vector mosquitoes inflict more human suffering than any other organism-and kill more than one million people each year. The mosquito genome projects facilitated research in new facets of mosquito biology, including functional genetic studies in the primary African malaria vector Anopheles gambiae and the dengue and yellow fever vector Aedes aegypti. RNA interference- (RNAi-) mediated gene silencing has been used to target genes of interest in both of these disease vector mosquito species. Here, we describe a procedure for preparation of chitosan/interfering RNA nanoparticles that are combined …

Identifying gaps in research prioritization: The global burden of neglected tropical diseases as reflected in the Cochrane database of systematic reviews.

BACKGROUND: Neglected tropical diseases (NTDs) impact disadvantaged populations in resource-scarce settings. Availability of synthesized evi … with each NTD. RESULTS: Overall, there was poor correlation between CDSR representation and DALYs. Yellow fever, echinococcus, onchocerciasis, and schistosomiasis representation was well-aligned with DALY. Leprosy, trachoma, dengue, leishmaniasis, and Chagas disease representation was greater, while cysticercosis, human African trypanosomiasis, ascariasis, ly …

Polymerases of hepatitis C viruses and flaviviruses: structural and mechanistic insights and drug development.

The family Flaviviridae comprises several major human pathogens including hepatitis C virus (genus hepacivirus), yellow fever virus, West Nile virus and dengue virus (genus flavivirus). Flaviviridae genomes comprise a single-stranded RNA segment encoding a single polyprotein that is subsequently processed into 10 mature viral proteins. The nonstructural proteins are released from the C-terminus of the polyprotein and contribute to the infectious cycle by forming membrane-bound, multi-protein compartments within host cells, named the replication complexes, where synthesis of new viral genomes t…

Optimization of the cutoff value for a commercial anti-dengue virus IgG immunoassay.

A commercial anti-dengue virus (anti-DENV) indirect IgG enzyme-linked immunosorbent assay (ELISA) for serological diagnosis was evaluated fo … e specificity of the anti-DENV IgG ELISA from 24% to 95.7%. Additionally, previous vaccination with yellow fever virus contributed to 52.8% of the false-positive rate in the anti-DENV IgG ELISA results. Optimization of the cutoff value of the anti-DENV IgG ELISA provided better interpretation and confidence in the results and eliminated the need for confirmati …

Antibody-dependent enhancement of dengue virus infection is inhibited by SA-17, a doxorubicin derivative.

Antibody-dependent enhancement (ADE) is thought to play a critical role in the exacerbation of dengue virus (DENV)-induced disease during a heterologous re-infection. Despite ADE's clinical impact, only a few antiviral compounds have been assessed for their anti-ADE activity. We reported earlier that SA-17, a doxorubicin derivative, efficiently inhibits the in vitro infection of DENV and yellow fever virus. Here we explored SA-17's mechanism of inhibition and investigated if the compound is active against ADE of DENV infection. Since enhanced infectivity stimulated by antibodies has been obser…

Flaviviruses in Europe: complex circulation patterns and their consequences for the diagnosis and control of West Nile disease.

In Europe, many flaviviruses are endemic (West Nile, Usutu, tick-borne encephalitis viruses) or occasionally imported (dengue, yellow fever viruses). Due to the temporal and geographical co-circulation of flaviviruses in Europe, flavivirus differentiation by diagnostic tests is crucial in the adaptation of surveillance and control efforts. Serological diagnosis of flavivirus infections is complicated by the antigenic similarities among the Flavivirus genus. Indeed, most flavivirus antibodies are directed against the highly immunogenic envelope protein, which contains both flavivirus cross-reac…

Proof of concept for a novel insecticide bioassay based on sugar feeding by adult Aedes aegypti (Stegomyia aegypti).

Aedes aegypti L. (Stegomyia aegypti) (Diptera: Culicidae) is the principal vector of dengue and yellow fever viruses in tropical and subtropical regions of the world. Disease management is largely based on mosquito control achieved by insecticides applied to interior resting surfaces and through space sprays. Population monitoring to detect insecticide resistance is a significant component of integrated disease management programmes. We developed a bioassay method for assessing insecticide susceptibility based on the feeding activity of mosquitoes on plant sugars. Our prototype sugar-insectici…

VIGOR extended to annotate genomes for additional 12 different viruses.

A gene prediction program, VIGOR (Viral Genome ORF Reader), was developed at J. Craig Venter Institute in 2010 and has been successfully per … y syncytial virus, alphavirus and Venezuelan equine encephalitis virus, norovirus, metapneumovirus, yellow fever virus, Japanese encephalitis virus, parainfluenza virus and Sendai virus. VIGOR accurately detects the complex gene features like ribonucleicacid editing, stop codon leakage and ribosomal shunting. Precisely identifying the mat_peptide cleavage for …