Loss of Fgfr1 and Fgfr2 in Scleraxis-lineage cells leads to enlarged bone eminences and attachment cell death

BACKGROUND Tendons and ligaments attach to bone are essential for joint mobility and stability in vertebrates. Tendon and ligament attachments (ie, entheses) are found at bony protrusions (ie, eminences), and the shape and size of these protrusions depend on both mechanical forces and cellular cues during growth. Tendon eminences also contribute to mechanical leverage for skeletal muscle. Fibroblast growth factor receptor (FGFR) signaling plays a critical role in bone development, and Fgfr1 and Fgfr2 are highly expressed in the perichondrium and periosteum of bone where entheses can be found. RESULTS AND CONCLUSIONS We used transgenic mice for combinatorial knockout of Fgfr1 and/or Fgfr2 in tendon/attachment progenitors (ScxCre) and measured eminence size and shape. Conditional deletion of both, but not individual, Fgfr1 and Fgfr2 in Scx progenitors led to enlarged eminences in the postnatal skeleton and shortening of long bones. In addition, Fgfr1/Fgfr2 double conditional knockout mice had more variation collagen fibril size in tendon, decreased tibial slope, and increased cell death at ligament attachments. These findings identify a role for FGFR signaling in regulating growth and maintenance of tendon/ligament attachments and the size and shape of bony eminences

The Global COVID-19 Observatory and Resource Center for Childhood Cancer: A response for the pediatric oncology community by SIOP and St. Jude Global

The COVID-19 pandemic quickly led to an abundance of publications and recommendations, despite a paucity of information on how COVID-19 affects children with cancer. This created a dire need for a trusted resource with curated information and a space for the pediatric oncology community to share experiences. The Global COVID-19 Observatory and Resource Center for Childhood Cancer was developed, launched, and maintained by the International Society of Pediatric Oncology and St. Jude Children's Research Hospital. The three components (Resource Library, Global Registry, and Collaboration Space) complement each other, establishing a mechanism to generate and transfer knowledge rapidly throughout the community.Fil: Moreira, Daniel C.. St. Jude Children's Research Hospital; Estados UnidosFil: Sniderman, Elizabeth. St. Jude Children's Research Hospital; Estados UnidosFil: Mukkada, Sheena. St. Jude Children's Research Hospital; Estados UnidosFil: Chantada, Guillermo Luis. Universidad Austral. Facultad de Ciencias Biomédicas. Instituto de Investigaciones en Medicina Traslacional. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Medicina Traslacional; ArgentinaFil: Bhakta, Nickhill. St. Jude Children's Research Hospital; Estados UnidosFil: Foster, Whitney. St. Jude Children's Research Hospital; Estados UnidosFil: Avula, Meghana. St. Jude Children's Research Hospital; Estados UnidosFil: Homsi, Maysam R.. St. Jude Children's Research Hospital; Estados UnidosFil: Faughnan, Lane. St. Jude Children's Research Hospital; Estados UnidosFil: Happ, Brooke. St. Jude Children's Research Hospital; Estados UnidosFil: Andujar, Allyson. St. Jude Children's Research Hospital; Estados UnidosFil: Sonnenfelt, Jason. St. Jude Children's Research Hospital; Estados UnidosFil: Dalvi, Rashmi. Bombay Hospital And Medical Research Centre; IndiaFil: Frazier, A. Lindsay. No especifíca;Fil: Hessissen, Laila. Universite Mohammed V. Rabat; Otros paises de ÁfricaFil: Kearns, Pamela R.. No especifíca;Fil: Luna Fineman, Sandra. No especifíca;Fil: Moreno, Arturo. Hospital Universitario de Puebla; MéxicoFil: Saghir Khan, Muhammad. No especifíca;Fil: Sullivan, Michael. Royal Children's Hospital, Melbourne; AustraliaFil: Devidas, Meenakshi. St. Jude Children's Research Hospital; Estados UnidosFil: Santana, Victor. St. Jude Children's Research Hospital; Estados UnidosFil: Caniza, Miguela. St. Jude Children's Research Hospital; Estados UnidosFil: Pritchard Jones, Kathy. University College London; Estados UnidosFil: Rodriguez Galindo, Carlos. St. Jude Children's Research Hospital; Estados Unido