Kif9 is an active kinesin motor required for ciliary beating and proximodistal patterning of motile axonemes.

Most motile cilia have a stereotyped structure of nine microtubule outer doublets and a single central pair of microtubules. The central pair of microtubules are surrounded by a set of proteins, termed the central pair apparatus. A specific kinesin, Klp1 projects from the central pair and contributes to ciliary motility in Chlamydomonas. The vertebrate ortholog, Kif9, is required for beating in mouse sperm flagella, but the mechanism of Kif9/Klp1 function remains poorly defined. Here, using Xenopus epidermal multiciliated cells, we show that Kif9 is necessary for ciliary motility and the proper distal localization of not only central pair proteins, but also radial spokes and dynein arms. In addition, single-molecule assays in vitro reveal that Xenopus Kif9 is a long-range processive motor, although it does not mediate long-range movement in ciliary axonemes in vivo. Together, our data suggest that Kif9 is integral for ciliary beating and is necessary for proper axonemal distal end integrity.

Culicoides (Diptera: Ceratopogonidae) midges, the vectors of African horse sickness virus--a host/vector contact study in the Niayes area of Senegal.

BACKGROUND: African horse sickness (AHS) is an equine disease endemic to Senegal. The African horse sickness virus (AHSV) is transmitted to the mammalian hosts by midges of the Culicoides Latreille genus. During the last epizootic outbreak of AHS in Senegal in 2007, 1,169 horses died from this disease entailing an estimated cost of 1.4 million euros. In spite of the serious animal health and economic implications of AHS, very little is known about determinants involved in transmission such as contact between horses and the Culicoides species suspected of being its vectors. METHODS: The monthly variation in host/vector contact was determined in the Niayes area, Senegal, an area which was severely affected by the 2007 outbreak of AHS. A horse-baited trap and two suction light traps (OVI type) were set up at each of five sites for three consecutive nights every month for one year. RESULTS: Of 254,338 Culicoides midges collected 209,543 (82.4%) were female and 44,795 (17.6%) male. Nineteen of the 41 species collected were new distribution records for Senegal. This increased the number of described Culicoides species found in Senegal to 53. Only 19 species, of the 41 species found in light trap, were collected in the horse-baited trap (23,669 specimens) largely dominated by Culicoides oxystoma (22,300 specimens, i.e. 94.2%) followed by Culicoides imicola (482 specimens, i.e. 2.0%) and Culicoides kingi (446 specimens, i.e. 1.9%). CONCLUSIONS: Culicoides oxystoma should be considered as a potential vector of AHSV in the Niayes area of Senegal due to its abundance on horses and its role in the transmission of other Culicoides-borne viruses.

Ex utero intrapartum treatment (EXIT), a resuscitation option for intra-thoracic foetal pathologies.

The ex utero intrapartum treatment (EXIT) procedure is designed to guarantee sufficient oxygenation for a foetus at risk of airway obstruction. This is achieved by improving lung ventilation, usually by establishing an airway during caesarean delivery whilst preserving the foetal-placental circulation temporarily. Indications for the EXIT procedure have extended from its original use in reversing iatrogenic tracheal obstruction in congenital diaphragmatic hernia to naturally occurring upper airway obstructions. We report our experience with a new and rarely mentioned indication for the EXIT procedure, intra-thoracic volume expansions. The elaboration of lowest risk scenarios through balancing risks with alternative options, foetal or neonatal intervention and coordination between professionals from various disciplines are the most important conditions for a successful EXIT procedure. The EXIT procedure requires a caesarean section that specifically differs from the traditional caesarean section during which uterine tone is maintained to minimize maternal bleeding. To guarantee foetal oxygenation during the EXIT procedure, profound uterine relaxation is desired. To gain time with optimal placental oxygenation in order to safely perform an airway intervention in a baby at risk of hypoxia may require deep inhalation anaesthesia and/or tocolytic agents. We review the EXIT procedure and present a case series from the University Hospital of Geneva that contrasts with the common indication for the EXIT procedure usually based on upper airway obstruction by its exclusive indication for intra-thoracic malformations/diseases.