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Human Synovial Mesenchymal Stem Cells Expressed Immunoregulatory Factors IDO and TSG6 in a Context of Arthritis Mediated by Alphaviruses.

Infection by arthritogenic alphaviruses (aavs) can lead to reactive arthritis, which is characterized by inflammation and persistence of the virus; however, its mechanisms remain ill-characterized. Intriguingly, it has been shown that viral persistence still takes place in spite of robust innate and adaptive immune responses, characterized notably by the infiltration of macrophages (sources of TNF-alpha) as well as T/NK cells (sources of IFN-gamma) in the infected joint. Aavs are known to target mesenchymal stem cells (MSCs) in the synovium, and we herein tested the hypothesis that the infecti…

Genetic diversity of Venezuelan alphaviruses and circulation of a Venezuelan equine encephalitis virus subtype IAB strain during an interepizootic period.

Several species of alphaviruses have been previously described in the Americas, some of which are associated with encephalitis and others are associated with arthralgia. Venezuelan equine encephalitis virus (VEEV) and eastern equine encephalitis virus (EEEV) are endemic to Venezuela, with the former being responsible for major outbreaks of severe and often fatal disease in animals and humans. The aim of this study was to analyze the genetic diversity of Venezuelan alphaviruses isolated during two decades (1973-1999) of surveillance in northern Venezuela. Phylogenetic analysis indicated the cir…

Chikungunya virus infection: an overview.

Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus belonging to the Togaviridae family, first isolated in Tanzania in 1952. The main vectors are mosquitoes from the Aedes species. Recently, the establishment of an envelope mutation increased infectivity for A. albopictus. CHIKV has recently re-emerged causing millions of infections in countries around the Indian Ocean characterized by climate conditions favourable to high vector density. Importation of human cases to European regions with high density of suitable arthropod vectors (such as A. albopictus) may trigger autochthonous o…

The effects of climate change and globalization on mosquito vectors: evidence from Jeju Island, South Korea on the potential for Asian tiger mosquito (Aedes albopictus) influxes and survival from Vietnam rather than Japan.

BACKGROUND: Climate change affects the survival and transmission of arthropod vectors as well as the development rates of vector-borne pathogens. Increased international travel is also an important factor in the spread of vector-borne diseases (VBDs) such as dengue, West Nile, yellow fever, chikungunya, and malaria. Dengue is the most important vector-borne viral disease. An estimated 2.5 billion people are at risk of infection in the world and there are approximately 50 million dengue infections and an estimated 500,000 individuals are hospitalized with dengue haemorrhagic fever annually. The

A post-epidemic study on awareness of vector habits of Chikungunya and vector indices in a rural area of Kerala.

Chikungunya struck Kerala in a devastating form in the years 2006 and 2007 and its after effects continued to 2008. In May 2008, a post epidemic study of the awareness of vector habits and prevalence of the vectors was done. A cross sectional study was conducted in a randomly selected Panchayat affected by Chikungunya in a rural area of Kerala, India. 93.3% respondents were aware that mosquitoes spread Chikungunya though 31.3% knew the type of mosquito that spreads it. 69% knew that the vector breeds in artificial collections of water. Although three-fourths (73.6%) had good knowledge, only 39

A study on chikungunya outbreak during 2007 in Kerala, south India.

BACKGROUND & OBJECTIVE: The first chikungunya outbreak occurred in Kerala during 2006 affecting 14 districts, followed by another during May 2007 affecting almost whole of the State. Four of the worst affected districts viz, Pathanamthitta, Idukki, Kottayam and Thrissur were surveyed during 2007 to understand the magnitude of the problem of chikungunya fever, particularly clinical signs and symptoms. METHODS: A total of 1265 persons from 310 houses were surveyed door-to-door in 20 different localities representing four affected districts. The history and examination findings from 354 clinical

Mucocutaneous features of Chikungunya fever: a study from an outbreak in West Bengal, India.

BACKGROUND: Chikungunya fever (CF) epidemic has recently re-emerged in India on a large scale affecting many parts of the country. We have reviewed the mucocutaneous manifestations of the disease in a number of cases. METHODS: Twenty six serologically proven cases of CF with rash from the district of 24-Paraganas (North) in the eastern Indian state of West Bengal were subjected to detailed clinical study to investigate the chronology and evolution of mucocutaneous lesions, the type and distribution of the rash, and systemic changes. RESULT: Most patients were in their 3rd and 4th decade (23%

Viral exanthems in the tropics.

Viral exanthems are a common problem in tropical regions, particularly affecting children. Most exanthems are transient and harmless, but some are potentially very dangerous. Pregnant women and malnourished or immunocompromised infants carry the greatest risk of adverse outcome. In this article, parvovirus B19; dengue and yellow fever; West Nile, Barmah Forest, Marburg, and Ebola viruses, and human herpesviruses; asymmetric periflexural exanthema of childhood; measles; rubella; enteroviruses; Lassa fever; and South American hemorrhagic fevers will be discussed.

[Detection of Sindbis virus-specific nucleic acid with SYBR GREEN I real time PCR assay].

BACKGROUND: To develop a rapid, specific and sensitive method for detecting Sindbis virus (SINV) with SYBR GREEN I real time PCR. METHODS: Total RNA of strains of Sindbis virus and a related virus were extracted and reverse transcribed to cDNAs. With the cDNAs as template, the SYBR GREEN I real time PCR assay was developed and optimized on ABI 7300 apparatus for specific-detection of Sindbis virus, and the sensitivity, specificity and reproducibility were evaluated. RESULTS: For the PCR, 55 degrees C was chosen as the optimal anneal temperature and 0.5 micromol/L as the optimal primer concen

Flavivirus isolations from mosquitoes collected from western Cape York Peninsula, Australia, 1999-2000.

After the 1st appearance of Japanese encephalitis virus (JE) on mainland Australia in 1998, a study was undertaken to investigate whether JE … ephalitis virus, Kunjin virus, Alfuy virus, and Kokobera virus (KOK) were isolated. Isolates of the alphaviruses Ross River virus, Barmah Forest virus (BF), and Sindbis virus (SIN) also were obtained. The majority (88%) of isolates were from members of the Culex sitiens subgroup. Single isolates of KOK, BF, and SIN were obtained from Ochlerotatus vigilax, Oc …

Application of enzyme immunoassay on infected cells (EIA-IC) for arboviruses.

Comparative titrations of alpha-, flavi- and Bunyamwera viruses were made by EIA-IC and according to cytopathic effect (CPE). Specific enzymatic reactions appeared earlier and in higher titres than CPE. The titres of dengue type 1, Mayaro, Powassan and Langat viruses measured by EIA-IC were comparable to those measured by intracerebral inoculation of mice. The cross-reactivity testing of EIA-IC among alphaviruses (Chikungunya, Sindbis and Mayaro), flaviviruses (Japanese encephalitis, Murray valley encephalitis, Kunjin, West Nile, yellow fever and louping ill, Powassan, Langat) and Bunyamwera a…

Chikungunya virus virus-like particle vaccine (Vimkunya) induces a rapid and durable antigen-specific CD4+ T cell response.

Chikungunya virus (CHIKV), a single-stranded, positive-sense RNA alphavirus, is transmitted to humans by infected Aedes mosquitoes. It poses an emerging threat to public health in Aedes-endemic countries and a growing risk to travelers visiting these countries. Typical acute symptoms include fever, arthralgia, rash, myalgia, fatigue and headache. In over 40% of cases, these symptoms can progress into chronic disease, primarily characterized by debilitating arthralgia. CHIKV vaccine (Vimkunya, Bavarian Nordic) is an aluminum hydroxide-adjuvanted virus-like particle (VLP) vaccine recently approv…

RNA Capping, Replication Complex Assembly, and Translational Regulation in Chikungunya Virus: Molecular Mechanisms and Antiviral Opportunities.

Chikungunya virus (CHIKV) is an emerging mosquito-borne alphavirus that has become a significant global public health concern due to its rapid spread and the debilitating acute and chronic joint pain (arthralgia) it causes. Understanding the molecular events that regulate CHIKV RNA synthesis and gene expression is essential for identifying vulnerable stages in the viral life cycle and guiding the development of targeted therapies. This narrative review summarises key aspects of CHIKV molecular biology, focusing on RNA capping, genome replication, and translation. CHIKV RNA capping is primarily…

Neuroaxis involvement in Chikungunya virus infection: a retrospective case series.

BACKGROUND: Chikungunya virus (CHIKV) is an arthropod-borne virus belonging to the genus Alphavirus; it has been increasingly linked to neurological complications. This study aimed to highlight the neurological manifestations of chikungunya virus infection. METHODS: This retrospective case series was conducted at the Aga Khan University Hospital, Karachi, Pakistan. Adult patients (aged 18 years and above) with typical arboviral prodrome (fever, arthralgias, myalgias) who tested positive for chikungunya IgM antibodies in serum and demonstrated new-onset neurological symptoms were included in t…

Standardized Diagnostic Assays for Omsk Hemorrhagic Fever Virus.

Omsk hemorrhagic fever is an acute zoonotic disease caused by Omsk hemorrhagic fever virus, a member of the genus Flavivirus (family Flavivi … ow fever virus, Zika virus, St. Louis encephalitis virus, and Tick-borne encephalitis virus) and an alphavirus (Venezuelan equine encephalitis virus) demonstrated no cross-reactivity. The assay demonstrated high sensitivity, specificity, and reproducibility, supporting its potential application in national and international Omsk hemorrhagic fever virus surve …

Development and validation of Mayaro virus with luciferase reporter genes as a tool for antiviral assays.

Arboviruses are etiological agents in an extensive group of emerging diseases with great clinical relevance in Brazil, due to the wide distr … viral drug screening using the compound EIDD-2749 (4'-Fluorouridine), which acts as an inhibitor of alphavirus RNA-dependent RNA polymerase.

Post-exposure intranasal IFNα suppresses replication and neuroinvasion of Venezuelan Equine Encephalitis virus within olfactory sensory neurons.

Venezuelan Equine Encephalitis virus (VEEV) may enter the central nervous system (CNS) within olfactory sensory neurons (OSN) that originate … critical and promising first evaluation of intranasal IFNα for the treatment of human encephalitic alphavirus exposures.

Организация двойной рентгеновской рентгеновской реплики на вирусе Чикунгуньи.

Альфавирусы - это вирусы, передающиеся через комары, в позитивном настроении - однострунные вирусы РНК. Среди альфавирусов вирус Чикунгуньи является крупным источником человеческих заболеваний, особенно в тропических и субтропических районах. Когда они вторгаются в клетку, альфавирусы создают специальные органили для репликации вирусного генома, так называемые правила сфе. Нормы Sphe формируются как зародыши наружу на плазменной мембране, и недавно было показано, что тонкая мембранная шея, соединяющая этот мембранный корень с цитоплазмой, охраняется двухмегадалтонным белковым комплексом, котор

Совпадение в аннотации оригинала
Alphaviruses are mosquito-borne, positive-sense single-stranded RNA viruses. Amongst the alphaviruses, chikungunya virus is notable as a large source of human illness, especially in tropical and subtropical regions. When they invade a cell, alphaviruses generate dedicated organelles for viral genome replication, so-called spherules. Spherules form as outward…

Bisacodyl Limits Chikungunya Virus Replication In Vitro and Is Broadly Antiviral.

Identifying novel antivirals requires significant time and resource investment, and the continuous threat of viruses to human health necessi … Institutes of Health's Developmental Therapeutic Program for activity against chikungunya virus, an alphavirus that is responsible for a significant outbreak in the Americas in 2013. Using this library, we identified several compounds with known antiviral activity, as well as several novel antivirals. Given its favorable in vitro activity and well-described …

Ecology of Eastern Equine Encephalitis Virus in the Southeastern United States: Incriminating Vector and Host Species Responsible for Virus Amplification, Persistence, and Dispersal.

Eastern equine encephalitis virus (EEEV; family Togaviridae, genus Alphavirus) is a mosquito-borne pathogen found in eastern North America that causes severe disease in humans and horses. The mosquito Culiseta melanura (Coquillett) (Diptera: Culicidae) is the primary enzootic vector of EEEV throughout eastern North America while several mosquito species belonging to diverse genera serve as bridge vectors. The ecology of EEEV differs between northern and southern foci, with respect to phenology of outbreaks, important vertebrate hosts, and bridge vector species. Active transmission is limited t…