Feto arlequin articulo

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renal stem cells (Figure 1). The failure of  whole bone marrow to have this protective  effect (12) may be due to the extremely small  numbers of MSCs present in the bone marrow or the large numbers of inflammatory  cells infused in this preparation. It remains  unclear  whether  the  protective  effect  of MSCs requires them to leave the bone marrow and transit through the renal circulation or whether these cells can exert protective effects from distant sites. Identifying  the protective factor(s) and the signals that  prompt MSCs to secrete it should now be a  priority in our attempts to develop new therapeutic approaches for improving patient  outcomes following acute renal failure. Address  correspondence  to:  Lloyd  G.  Cantley,  Department  of  Internal Medicine, Yale University, 333 Cedar Street, Box  208029, New Haven, Connecticut 06520,  USA.  Phone:  (203)  785-7110;  Fax:  (203)  785-3756; E-mail: Lloyd.Cantley@yale.edu.
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Harlequin ichthyosis unmasked: a defect of lipid transport
Alain Hovnanian
Department of Medical Genetics and INSERM U563, Purpan Hospital, Toulouse, France.

Harlequin ichthyosis (HI) — the most severe form of keratinizing disorders, often lethal in the neonatal period — ischaracterized by a profound thickening of the keratin skin layer, a dense “armor”-like scale that covers the body, and contraction abnormalities of the eyes, ears, and mouth. In this issue of the JCI, Akiyama et al. report that mutations in ABCA12 caused defective lipid transport that significantly impacted normal development of the...