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Persistent seropositivity for yellow fever in a previously vaccinated autologous hematopoietic stem cell transplantation recipient.

The duration of a protective level of yellow fever antibodies after autologous hematopoietic stem cell transplantation in a previously vaccinated person is unclear. The case of a patient who had previously been vaccinated for yellow fever and who remained seropositive for 22 months after autologous peripheral blood stem cell transplantation for malignant lymphoma is described herein.

Analysis of a Reverse Transcription Loop-mediated Isothermal Amplification (RT-LAMP) for yellow fever diagnostic.

Yellow Fever virus (YFV) is an important human pathogen in tropical areas of Africa and South America. Although an efficient vaccine is available and has been used since the early 1940s, sylvatic YFV transmission still occurs in forested areas where anthropogenic actions are present, such as mineral extraction, rearing livestock and agriculture, and ecological tourism. In this context, two distinct techniques based on the RT-PCR derived method have been previously developed, however both methods are expensive due to the use of thermo cyclers and labeled probes. We developed isothermal genome a…

Улучшенная генетическая стабильность рекомбинантной желтой лихорадки 17D вируса, выражающего осколок гена чечевицы Гаг.

Ранее мы разработали метод построения жизнеспособной рекомбинантной Желтой лихорадки (YF) 17D вирусов, выражающих гетерологические полипептиды, включая часть белка Симианского иммунодефицитного вируса (SIV). Однако выраженный регион, включающий остатки аминокислот от 45 до 269, является генетически нестабильным. В этом исследовании мы повысили генетическую стабильность этого рекомбинантного вируса YF 17D, введя мутации в элемент IRES, локализованный в 5' конце гена SIV. Новый устойчивый рекомбинантный вирус вызвал адаптивную иммунную реакцию, аналогичную тем, которые были вызваны исходным реко

Совпадение в аннотации оригинала
We have previously designed a method to construct viable recombinant Yellow Fever (YF) 17D viruses expressing heterologous polypeptides including part of the Simian Immunodeficiency Virus (SIV) Gag protein. However, the expressed region, encompassing amino acid residues from 45 to 269, was genetically unstable. In this study, we improved the genetic stabilit…

Adverse events following yellow fever immunization: Report and analysis of 67 neurological cases in Brazil.

Neurological adverse events following administration of the 17DD substrain of yellow fever vaccine (YEL-AND) in the Brazilian population are described and analyzed. Based on information obtained from the National Immunization Program through passive surveillance or intensified passive surveillance, from 2007 to 2012, descriptive analysis, national and regional rates of YFV associated neurotropic, neurological autoimmune disease, and reporting rate ratios with their respective 95% confidence intervals were calculated for first time vaccinees stratified on age and year. Sixty-seven neurological …

First international external quality assessment study on molecular and serological methods for yellow fever diagnosis.

OBJECTIVE: We describe an external quality assurance (EQA) study designed to assess the efficiency and accurateness of molecular and serological methods used by expert laboratories performing YF diagnosis. STUDY DESIGN: For molecular diagnosis evaluation, a panel was prepared of 14 human plasma samples containing specific RNA of different YFV strains (YFV-17D, YFV South American strain [Brazil], YFV IvoryC1999 strain), and specificity samples containing other flaviviruses and negative controls. For the serological panel, 13 human plasma samples with anti-YFV-specific antibodies against differ

Полярная ось в желтой лихорадке с яйцеклетки комаров эдеса (Стегомии) маскируется из-за инфохимии.

Водные и связанные с водой насекомые должны найти подходящие водоемы, чтобы сложить в них яйца и позволить своим водным личинкам развиваться. Известно, что более 300 видов решают эту задачу с помощью позитивной полярной оси, опираясь главным образом на горизонтализованный полярный свет, отражаемый с водной поверхности. Желтый комарь лихорадки Аэдес (Стегомиа) считается исключением, поскольку его местообитания определяется химическими сигналами, например запахом конома, яйцами или водяным паром. Сейчас мы демонстрируем с помощью экспериментов с двойным выбором, что горизонтализованный полярный

Совпадение в аннотации оригинала
Aquatic and water-associated insects need to locate suitable bodies of water to lay their eggs in and allow their aquatic larvae to develop. More than 300 species are known to solve this task by positive polarotaxis, relying primarily on the horizontally polarized light reflected from the water surface. The yellow fever mosquito Aedes (Stegomyia) aegypti has…

Evolution of insect arylalkylamine N-acetyltransferases: structural evidence from the yellow fever mosquito, Aedes aegypti.

Arylalkylamine N-acetyltransferase (aaNAT) catalyzes the transacetylation from acetyl-CoA to arylalkylamines. aaNATs are involved in sclerotization and neurotransmitter inactivation in insects. Phyletic distribution analysis confirms three clusters of aaNAT-like sequences in insects: typical insect aaNAT, polyamine NAT-like aaNAT, and mosquito unique putative aaNAT (paaNAT). Here we studied three proteins: aaNAT2, aaNAT5b, and paaNAT7, each from a different cluster. aaNAT2, a protein from the typical insect aaNAT cluster, uses histamine as a substrate as well as the previously identified aryla

Mutation and docking studies on NS2b-NS3 complex from yellow fever virus towards drug discovery.

UNLABELLED: Yellow fever virus is the causative agent of Yellow fever. The genome of the virus contains three structural and seven non-structural proteins. Of these seven nonstructural proteins, NS2B-NS3 protein complex has protease activity required for viral replication. Predicting the 3D structure of this complex and studying the interaction of residues at the recognized catalytic triad of the complex is an integral part to understand the virus replication mechanism. In the present study, the structure was determined for NS2B-NS3 complex by Homology modeling and modeled structure was valida…

Successful immunization of an allogeneic bone marrow transplant recipient with live, attenuated yellow Fever vaccine.

Vaccination against yellow fever is effective, but available live virus vaccines are not recommended for use in immunocompromised or elderly patients. We report the successful and uneventful immunization of a 62-year-old man with a history of allogeneic bone marrow transplant and discuss evidence for this recommendation.

Restricted replication and lysosomal trafficking of yellow fever 17D vaccine virus in human dendritic cells.

The yellow fever virus attenuated 17D vaccine strain is a safe and effective vaccine and a valuable model system for evaluating immune responses against attenuated viral variants. This study compared the in vitro interactions of the commercially available yellow fever vaccine (YF-VAX), Dengue virus and the live-attenuated dengue vaccine PDK50 with dendritic cells (DCs), the main antigen-presenting cells at the initiation of immune responses. Similar to PDK50, infection with YF-VAX generated activated DCs; however, for YF-VAX, activation occurred with limited intracellular virus replication. Th…

nanos gene control DNA mediates developmentally regulated transposition in the yellow fever mosquito Aedes aegypti.

Transposable elements (TEs) are proposed as a basis for developing drive systems to spread pathogen resistance genes through vector mosquito populations. The use of transcriptional and translational control DNA elements from genes expressed specifically in the insect germ line to mediate transposition offers possibilities for mitigating some of the concerns about transgene behavior in the target vector species and eliminating effects on nontarget organisms. Here, we describe the successful use of the promoter and untranslated regions from the nanos (nos) orthologous gene of the yellow fever mo…

Yellow fever vaccination: some thoughts on how much is enough [Vaccine 23 (2005) 3908-3914].

In a recently published article in this journal, Massad et al. contraindicates yellow fever vaccination to persons 60 years or older, considering that the risk of serious adverse events is higher for this age class. The conclusion was based on the input of available data on age-related probabilities of developing serious adverse events in the United States, as well on other data not firmly established. We consider such contraindication inadequate, because the data input has limitations, higher letality of wild-type yellow fever infection in older adults, risk of introduction of yellow fever by…

Molecular characterization of sodium/proton exchanger 3 (NHE3) from the yellow fever vector, Aedes aegypti.

Transport across insect epithelia is thought to depend on the activity of a vacuolar-type proton ATPase (V-ATPase) that energizes ion transport through a secondary proton/cation exchanger. Although several of the subunits of the V-ATPase have been cloned, the molecular identity of the exchanger has not been elucidated. Here, we present the identification of sodium/proton exchanger isoform 3 (NHE3) from yellow fever mosquito, Aedes aegypti (AeNHE3). AeNHE3 localizes to the basal plasma membrane of Malpighian tubule, midgut and the ion-transporting sector of gastric caeca. Midgut expression of N…

Safety and efficacy of chimeric yellow Fever-dengue virus tetravalent vaccine formulations in nonhuman primates.

To construct chimeric YF/DEN viruses (ChimeriVax-DEN), the premembrane (prM) and envelope (E) genes of yellow fever (YF) 17D virus were replaced with those of each wild-type (WT) dengue (DEN) virus representing serotypes 1 to 4. ChimeriVax-DEN1-4 vaccine viruses were prepared by electroporation of Vero cells with RNA transcripts prepared from viral cDNA (F. Guirakhoo, J. Arroyo, K. V. Pugachev, C. Miller, Z.-X. Zhang, R. Weltzin, K. Georgakopoulos, J. Catalan, S. Ocran, K. Soike, M. Ratteree, and T. P. Monath, J. Virol. 75:7290-7304, 2001; F. Guirakhoo, K. Pugachev, J. Arroyo, C. Miller, Z.-X.…

Neuroadapted yellow fever virus 17D: determinants in the envelope protein govern neuroinvasiveness for SCID mice.

A molecular clone of mouse-neuroadapted yellow fever 17D virus (SPYF-MN) was used to identify critical determinants of viral neuroinvasiveness in a SCID mouse model. Virus derived from this clone differs from nonneuroinvasive YF5.2iv virus at 29 nucleotide positions, encoding 13 predicted amino acid substitutions and 2 substitutions in the 3' untranslated region (UTR). The virulence determinants of SPYF-MN for SCID mice were identified by constructing and characterizing intratypic viruses in which the E protein of SPYF-MN was expressed in the YF5.2iv background (SPYF-E) or the E protein of YF5…

[Culicidae insect fauna from rural zone in Amazonas State with incidence of sylvatic yellow fever].

After the occurrence of 14 sylvatic yellow fever cases in 10 cities in the State of Amazonas during 1996, an investigation into the presence of sylvatic yellow fever vectors was carried out. The material of larvae and adult insects was collected around residences and canopy trees within forests, using a light trap (CDC) and human bait. A total of 424 insects was collected. Thirty seven species were identified, some of which were sylvatic yellow fever vectors: Haemagogus janthinomys, Ha. leucocelaenus, Aedes fulvus.

Host-range restriction of chimeric yellow fever-West Nile vaccine in fish crows (Corvus ossifragus).

We evaluated a recombinant virus chimera, ChimeriVax-WN, in which the West Nile virus (WNV) surface protein genes (pre-membrane [prM] and envelope [E]) are substituted into the genome of the 17D vaccine strain yellow fever virus (YF-17D), as a vaccine candidate for protection of birds from WNV disease. Using fish crows (Corvus ossifragus) as a model, we found that none of eight crows that received two high doses of vaccine (approximately 100,000 plaque-forming units [PFU]) developed viremia and only one developed WNV-neutralizing antibodies. When challenged with subcutaneous injection of 2,000…

In vitro potency assay for yellow fever vaccines: comparison of three vero cell lines sources.

Quality control of Yellow Fever vaccines performed by Control Authorities prior to marketing vaccines batches requires in vitro potency assays. The two currently available methods are the plaque formation assay and the cytopathic effect assay based on the use of porcine kidney PS cells or monkey kidney Vero cells. Among several sources of variation in virus titration, the cell systems are considered as important issues and Quality Assurance strongly recommends working with cell banks from certified suppliers. The aim of our study was to compare the behaviour and the sensitivity of three Vero c…