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Impact of elevated CO2 background levels on the host-seeking behaviour of Aedes aegypti.

Mosquitoes rely on carbon dioxide (CO2) to detect and orient towards their blood hosts. However, the variable and rapid fluctuations of atmospheric CO2 concentrations may have an impact on the host-seeking behaviour of mosquitoes. In this study, we analysed the effect of transient elevated background levels of CO2 on the host-seeking behaviour and the physiological characteristics of the CO2-sensitive olfactory receptor neurones (ORNs) in female yellow fever mosquitoes, Aedes aegypti. We show that the take-off and source contact behaviour of A. aegypti is impeded at elevated background levels …

Systems biology in the development of HIV vaccines.

PURPOSE OF REVIEW: In the present review, we will provide the scientific rationale for applying systems biology to the development of vaccin … ECENT FINDINGS: Systems biology has been recently applied to the characterization of the protective yellow fever vaccine YF17D and of seasonal flu vaccines. This has been instrumental in the identification of the components of the immune response that need to be stimulated by the vaccine in order to generate protective immunity. It is worth noting that a syste …

Novel approaches to flavivirus drug discovery.

INTRODUCTION: The members of the family Flaviviridae, including West Nile virus, yellow fever virus and dengue virus, are important human pathogens that are expanding their impact around the globe. The four serotypes of dengue infect 50-100 million people each year, yet the only clinical treatment is supportive care to reduce symptoms. Drugs that employ novel inhibition mechanisms and targets are urgently needed to combat the growing incidence of dengue worldwide. AREAS COVERED: The authors discuss recently discovered flavivirus inhibitors with a focus on antivirals targeting non-enzymatic pr…

Silica nanoparticle: a potential new insecticide for mosquito vector control.

Presently, there is a need for increased efforts to develop newer and effective methods to control mosquito vectors as the existing chemical … ttraction/deterrence) of mosquito species that transmit human diseases, namely malaria (Anopheles), yellow fever, chickungunya and dengue (Aedes), lymphatic filariasis and encephalitis (Culex and Aedes). Application of hydrophobic nanosilica at 112.5 ppm was found effective against mosquito species tested. The larvicidal effect of hydrophobic nanosilica on mos …

Flavivirus replication complex assembly revealed by DNAJC14 functional mapping.

DNAJC14 is an Hsp40 family member that broadly modulates flavivirus replication. The mechanism by which DNAJC14 stoichiometrically participates in flavivirus replication complex (RC) formation is unknown; both reduced and elevated levels result in replication inhibition. Using yellow fever virus (YFV), we demonstrate that DNAJC14 redistributes and clusters with YFV nonstructural proteins via a transmembrane domain and a newly identified membrane-binding domain (MBD), which both mediate targeting to detergent-resistant membranes. Furthermore, the RC and DNAJC14 reside as part of a protein inter…

British Society for Allergy and Clinical Immunology guidelines for the management of egg allergy.

This guideline advises on the management of patients with egg allergy. Most commonly, egg allergy presents in infancy, with a prevalence of … hildren with egg allergy should receive measles, mumps and rubella (MMR) vaccination. Influenza and yellow fever vaccines should only be considered in egg-allergic patients under the guidance of an allergy specialist. This guideline was prepared by the Standards of Care Committee (SOCC) of the British Society for Allergy and Clinical Immunology (BSACI) and is …

A simple colorimetric assay for specific detection of glutathione-S transferase activity associated with DDT resistance in mosquitoes.

BACKGROUND: Insecticide-based methods represent the most effective means of blocking the transmission of vector borne diseases. However, ins … ST)-based DDT resistance in mosquito species, such as Aedes aegypti, the major vector of dengue and yellow fever worldwide. The colorimetric assay is based on the specific alkyl transferase activity of Epsilon GSTs for the haloalkene substrate iodoethane, which produces a dark blue colour highly correlated with AaGSTE2-2-overexpression in individual mosquitoes …

New approaches to design HIV-1 T-cell vaccines.

PURPOSE OF REVIEW: Following the evidence that T-cell responses are crucial in the control of HIV-1 infection, vaccines targeting T-cell responses were tested in recent clinical trials. However, these vaccines showed a lack of efficacy. This review attempts to define the qualitative and quantitative features that are desirable for T-cell-induced responses by vaccines. We also describe strategies that could lead to achievement of this goal. RECENT FINDINGS: Using the yellow fever vaccine as a benchmark of an efficient vaccine, recent studies identified factors of immune protection and more imp…

Genetic structure of Aedes aegypti in the city of Córdoba (Argentina), a recently reinfested area.

To understand the transmission of a vector-borne disease, knowledge of the magnitude of dispersal among vector populations is essential beca … genetic variability and differentiation among populations of Ae. aegypti (the vector of dengue and yellow fever) in Córdoba, the second largest city in Argentina. We detected similar levels of genetic variability (He between 0.351-0.404) across samples and significant genetic differentiation between most population pairs within the city (F ST between 0.0013-0 …

Vector-borne diseases.

Vector-borne diseases have been the scourge of man and animals since the beginning of time. Historically, these are the diseases that caused the great plagues such as the 'Black Death' in Europe in the 14th Century and the epidemics of yellow fever that plagued the development of the New World. Others, such as Nagana, contributed to the lack of development in Africa for many years. At the turn of the 20th Century, vector-borne diseases were among the most serious public and animal health problems in the world. For the most part, these diseases were controlled by the middle of the 20th Century …

Transmission of zoonoses through immigration and tourism.

More than 200 of the documented zoonoses represent a high proportion of the infectious diseases that cause cases of morbidity and mortality and almost 75% are emerging infections. Immigration and tourism are human activities that are included in the broader field of human migration and travel. Travel plays a significant role in the emergence and spread of disease. The migration of humans has provided the route of spread for infectious diseases and zoonoses (for example, plague, yellow fever, monkey pox and severe acute respiratory syndrome). Tourism constitutes a small fraction of overall move…

Using a climate-dependent model to predict mosquito abundance: application to Aedes (Stegomyia) africanus and Aedes (Diceromyia) furcifer (Diptera: Culicidae).

Mosquitoes, acting as vectors, are involved in the transmission of viruses. Thus, their abundances, which strongly depend on the weather and … rs of two mosquito species, Aedes africanus (Theobald) and Aedes furcifer (Edwards), vectors of the yellow fever virus in Ivory Coast. As both these species breed in tree holes, the water dynamics in the tree hole was reproduced from daily rainfall data. The results we obtained showed a good match between the simulated populations and the field data over the t …

A stochastic population dynamics model for Aedes aegypti: formulation and application to a city with temperate climate.

Aedes aegypti is the main vector for dengue and urban yellow fever. It is extended around the world not only in the tropical regions but also beyond them, reaching temperate climates. Because of its importance as a vector of deadly diseases, the significance of its distribution in urban areas and the possibility of breeding in laboratory facilities, Aedes aegypti is one of the best-known mosquitoes. In this work the biology of Aedes aegypti is incorporated into the framework of a stochastic population dynamics model able to handle seasonal and total extinction as well as endemic situations. Th…

Ancestry and progeny of nutrient amino acid transporters.

The biosynthesis of structural and signaling molecules depends on intracellular concentrations of essential amino acids, which are maintained by a specific system of plasma membrane transporters. We identify a unique population of nutrient amino acid transporters (NATs) within the sodium-neurotransmitter symporter family and have characterized a member of the NAT subfamily from the larval midgut of the Yellow Fever vector mosquito, Aedes aegypti (aeAAT1, AAR08269), which primarily supplies phenylalanine, an essential substrate for the synthesis of neuronal and cuticular catecholamines. Further…

Godzilla in the corridor: The Ontario SARS crisis in historical perspective.

Ontario nurses were employed as the front-line workers when SARS descended upon Toronto in March 2003. Once the crisis had subsided, many nu … historical epidemics of unknown or contested epidemiology. The historical literature on nursing in yellow fever, cholera and influenza epidemics has been employed to offer insight. The goal is to determine whether the SARS outbreak was a unique experience for nurses or whether similar experiences were shared by nurses in the past? In summary, the reactions of …

[Aedes (Stegomyia) aegypti (Linnaeus, 1762) breeding sites in native bromeliads in Vitória City, ES].

Some insects that are vectors of human diseases have accompanied man in his migrations throughout the world and breed exclusively in the proximity of human dwellings. The mosquito Aedes aegypti has been responsible for epidemics of dengue in Brazil and its presence also constitutes a serious risk for future outbreaks of urban yellow fever. The failure of campaigns to eradicate this species justifies the search for alternative breeding sites, which may be beyond the reach of present control measures. In this study the occurrence of Aedes aegypti breeding sites in native bromeliads on rocky slop…

Потенциальная роль фенилалиновой гидроксилазы в иммунной реакции комаров.

У комаров меланотическая инкапсуляция иммунной реакции является важным механизмом противодействия филариальным червим и паразитам малярии. Скорость, ограничивающая субстрат для производства меланина, представляет собой тиросин, который гидроксилизируется феноксидазом (PO) для производства 3, 4-дигидроксифенилалалин. Единственный способ эндогенного производства тиросина заключается в гидроксилировании фениланина с помощью фенилалиновой гидроксилазы (ПАУ). В этом исследовании мы описываем потенциальную роль ПАУ в меланотической иммунной реакции на желтую лихорадку комаров, Aedes aegypti. 1,6 кб

Совпадение в аннотации оригинала
In mosquitoes the melanotic encapsulation immune response is an important resistance mechanism against filarial worms and malaria parasites. … lase (PAH). In this study we describe a potential role for PAH in melanotic immune responses in the yellow fever mosquito, Aedes aegypti. A 1.6 kb A. aegypti PAH cDNA, encoding a 51 kDa protein, was isolated and subsequently expressed in an Escherichia coli expression system. In developing mosquitoes, PAH transcript is present in all stages and it is different …

Plant growth regulatory effect and insecticidal activity of the extracts of the Tree of Heaven (Ailanthus altissima L.).

BACKGROUND: There is an urgent need to explore and utilize naturally occurring products for combating harmful agricultural and public health … lant growth enhancing effect at lower concentrations. The extract was slightly insecticidal against yellow fever mosquito larvae (Aedes aegypti). CONCLUSIONS: The extract or its semi-purified fractions of A. altissima were strong plant growth inhibitors, therefore good candidates as potential environmentally safe and effective agricultural pest management age …

[Pneumonia caused by Nocardia nova].

This is the first clinical report of a case of pneumonia caused by Nocardia nova in Japan. A 52 year-old woman who had received steroids and cyclophosphamide for six years because of polymyositis was admitted to our hospital for further examination. On admission she had a mild cough, and her chest radiography and computed tomography revealed bilateral multiple nodules, some of which were cavitated. She developed a cough productive of yellow sputum and fever up to 38 degrees C. Examination of the sputum revealed a gram-positive branched organism and sputum cultures repeatedly grew Nocardia spec

The countrie continues sicklie': white mortality in Jamaica, 1655-1780.

The tropical regions of the New World in the early modern era offered European migrants great wealth but were also demographically deadly. This paper presents hard data on white mortality in seventeenth- and eighteenth-century Jamaica and shows that white susceptibility to disease, especially yellow fever, led to appalling white mortality. High white mortality, especially in urban areas in the first half of the eithteenth century, meant that Jamaica did not become a settler society full of native-born whites, as occurred in plantation British North America. The failure of white settlement and …