Genomic variants within chromosome 14q32.32 regulate bone mass through MARK3 signaling in osteoblasts

Bone mineral density (BMD) is a highly heritable predictor of osteoporotic fracture. GWAS have identified hundreds of loci influencing BMD, but few have been functionally analyzed. In this study, we show that SNPs within a BMD locus on chromosome 14q32.32 alter splicing and expression of PAR-1a/microtubule affinity regulating kinase 3 (MARK3), a conserved serine/threonine kinase known to regulate bioenergetics, cell division, and polarity. Mice lacking Mark3 either globally or selectively in osteoblasts have increased bone mass at maturity. RNA profiling from Mark3-deficient osteoblasts suggested changes in the expression of components of the Notch signaling pathway. Mark3-deficient osteoblasts exhibited greater matrix mineralization compared with controls that was accompanied by reduced Jag1/Hes1 expression and diminished downstream JNK signaling. Overexpression of Jag1 in Mark3-deficient osteoblasts both in vitro and in vivo normalized mineralization capacity and bone mass, respectively. Together, these findings reveal a mechanism whereby genetically regulated alterations in Mark3 expression perturb cell signaling in osteoblasts to influence bone mass.     

A case report of pseudoaneurysm after a core needle biopsy of breast cancer

Breast pseudoaneurysms after a core needle biopsy are a rare complication with a low incidence. However, it is important to be aware of the possibility of complications that require treatment.     

Successful treatment of hemorrhagic bullous Henoch‐Schonlein purpura with intravenous immunoglobulins

Henoch‐Schonlein purpura (HSP) is the most common systemic vasculitis in childhood. There is no consensus about the management for isolated cutaneous manifestations in HSP. We describe a case of HSP presenting with severe skin lesions that did not respond to standard therapy with corticosteroids. The 11‐year‐old child was treated with intravenous immunoglobulins, which induced rapid and persistent resolution of symptomatology.