La sédation consciente par inhalation de protoxyde d'azote en odontologie pédiatrique

MONTPELLIER-BU Médecine UPM (341722108) / SudocMONTPELLIER-BU Odontologie (341722110) / SudocPARIS-BIUM (751062103) / SudocMONTPELLIER-BU Médecine (341722104) / SudocSudocFranceF

Genome Microevolution of Chikungunya Viruses Causing the Indian Ocean Outbreak

Article Number: e263International audienceA chikungunya virus outbreak of unprecedented magnitude is currently ongoing in Indian Ocean territories. In Réunion Island, this alphavirus has already infected about one-third of the human population. The main clinical symptom of the disease is a painful and invalidating poly-arthralgia. Besides the arthralgic form, 123 patients with a confirmed chikungunya infection have developed severe clinical signs, i.e., neurological signs or fulminant hepatitis

Localization of the E1 Changes on the 3D Structure Modelled from the Crystal Structure of SFV E1

<div><p>(A) Ribbon diagram of E1, with domain I coloured red, domain II yellow, and domain III blue. Green tubes mark the disulfide bonds. The fusion peptide, at the tip of the molecule (in domain II) is coloured orange and labelled. The N-terminus and the C-terminus observed in the crystal (which is 30 aa upstream of the trans-membrane region) are also labelled. The two unique changes observed in the Indian Ocean isolates are indicated by stars and labelled: positions 226 (white) and 284 (magenta).</p> <p>(B) Partial representation (one octant, slightly extended) of the icosahedral E1 scaffold at the surface of the virion, viewed down a 5-fold symmetry axis. One E1 protomer is highlighted in colours, as in (A); all the others are represented in grey. The location of the some of the icosahedral symmetry axes are drawn as solid black symbols: pentagon for 5-fold axis, triangle for 3-fold axes, ellipse for 2-fold axes (which in the T = 4 lattice of alphaviruses are coincident with quasi 6-fold axes). Open triangles indicate roughly the location of the E2 trimers that interact tightly with E1, covering domain II and the fusion peptide, and presenting the main antigenic sites. The open triangles mark also quasi 3-fold symmetry axes of the T = 4 surface icosahedral lattice. A magenta ball marks the location of Glu 284, at an inter-E1 protomer contact site. This contact is propagated 240 times at the surface lattice (note all pink balls drawn on the grey protomers). Note that the fusion peptide, in orange, is pointing up and away from contacts with other E1 protomers. This is more easily seen at the periphery of the virion, where one of them is labelled (FP). In the virion, this region of E1 is not accessible, covered underneath the E2 molecule [<a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.0030263#pmed-0030263-b020" target="_blank">20</a>]. </p></div

Proposed Evolutionary Scenario of CHIKV Isolates from the Indian Ocean Outbreak

<div><p>The scenario is based on six genome sequences determined by direct sequencing of RT-PCR products obtained using RNA extracts as templates; the sequences (Seq.) thus correspond to consensus sequences of the possible mixture of coexisting genomes (quasispecies).</p> <p>Inset: number of cases of E1-226A and E1-226V at different time intervals in Réunion Island, based on partial E1 sequences. E1-226V was observed in consensus sequences 2, 3, and 4, and therefore most E1-226V isolates genotyped based on partial E1 sequences are likely related to these genotypes. However, the independent appearance of E1-226V in other genotypes cannot be excluded. The location, size, and relative position of the islands and the African border are indicative. Consensus sequence 1 was obtained from a Réunion patient who travelled back from Comoros in March 2005, and from a Réunion Island patient. Sequences 2–4 were sampled in Réunion Island; sequence 5 was sampled in the Seychelles. The strain codes are given under the corresponding sequences. The question mark in Comoros Archipelago indicates that Sequence 1 possibly originates from Comoros. The dotted link between Sequence 1 and Sequence 5 indicates that the transmission route is hypothetical.</p> <p>CSF, cerebrospinal fluid; Int., deduced intermediate sequence, which was not sampled.</p></div