Chikungunya virus (CHIKV) is an emerging arbovirus and is an important human pathogen. Infection of humans by CHIKV can cause a syndrome characterized by fever, headache, rash, nausea, vomiting, myalgia, arthralgia and occasionally neurological manifestations such as acute limb weakness. It is also associated with a fatal haemorrhagic condition. CHIKV is geographically distributed from Africa through Southeast Asia and South America, and its transmission to humans is mainly through the Aedes aegypti species mosquitoes. The frequency of recent epidemics in the Indian Ocean and La Reunion islands suggests that a new vector perhaps is carrying the virus, as Aedes aegypti are not found there. In fact, a relative the Asian tiger mosquito, Aedes albopictus, may be the culprit which and has raised concerns in the world health community regarding the potential for a CHIK virus pandemic. Accordingly steps should be taken to develop methods for control of CHIKV. Unfortunately, currently is no specific treatment for Chikungunya virus and there is no vaccine currently available. Here we present data of a novel consensus-based approach to vaccine design for CHIKV, employing a DNA vaccine strategy. The vaccine cassette was designed based on CHIKV Capsid and Envelope specific consensus sequences with several modifications, including codon optimization, RNA optimization, the addition of a Kozak sequence, and a substituted immunoglobulin E leader sequence. The expression of Capsid, envelope E1 and E1 was evaluated using T7-coupled transcription/translation and immunoblot analysis. A recently developed, adaptive constant-current electroporation technique was used to immunize C57BL/6 mice with an intramuscular injection of plasmid coding for the CHIK-Capsid, E1 and E2. Analysis of cellular immune responses, including epitope mapping, demonstrates that electroporation of these constructs induces both potent and broad cellular immunity. In addition, antibody ELISAs demonstrate that these synthetic immunogens are capable of inducing high titer antibodies capable of recognizing native antigen. Taken together, these data support further study of the use of consensus CHIK antigens in a potential vaccine cocktail.

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Background: Although the finding of SARS coronavirus (SARS-CoV) in caged palm civets suggested that wild animals are the origin of SARS-CoV, subsequent studies suggested that civet may have served only as an amplification host. In 2005, we identified a coronavirus closely related to SARS-CoV (bat-SARS-CoV) in Chinese horseshoe bats. However, it remains to be determined if bat-SARS-CoV or other coronaviruses in bats are the direct progenitor of SARS-CoV.Methods: To understand the diversity and evolution of coronaviruses in bats, a 2-year surveillance study for coronaviruses was conducted in bats from various rural areas in Hong Kong. As coronaviruses are known to have high recombination frequency, the genomes of the identified novel coronaviruses were also sequenced and analyzed to determine possible recombination events responsible for interspecies transmission.Results: Among 1389 bats of 16 species from 24 different locations, coronaviruses were identified from anal swabs of 132 (9.5%) bats by RT-PCR. Phylogenetic analysis revealed

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Calcium hexaluminate (CaO·6Al2O3–CA6) is usually associated as the product reaction between alumina and CA2 (CaO·2Al2O3) in cement‐bonded refractory castables. However, some investigations related to the Al2O3–CaO–MgO ternary system have indicated that CA6 could be generated by additional routes, involving two other high‐alumina phases: CaMg2Al16O27 (CM2A8) and Ca2Mg2Al28O46 (C2M2A14). Considering the lack of conclusive studies on this subject in the refractories field, the present study addresses an in‐depth microstructural evolution analysis of high‐alumina castables containing in situ or preformed spinel (MgAl2O4) in order to check the actual CA6 development steps in the presence of an MgO‐containing phase. By scanning electron microscopy (SEM) and thermodynamic calculations, it was observed that CA6 formation took place indeed as a result of the decomposition reaction of CM2A8, which was firstly generated due to the interaction between spinel and Al2O3–CaO–Na2O–SiO2 liquid. Although, the results confirmed this complex CA6 formation route regardless of the spinel incorporation method (pre‐formed grains addition or in situ reaction), the CA6 crystals distribution after the thermal treatment was entirely affected by the previous spinel grains location. Those different microstructural profiles could be the conclusive aspects to explain the poorer slag resistance of preformed spinel‐containing castables when in contact with steel ladle slags.