Friend turned foe: selfish behavior of a spontaneously arising mitochondrial deletion in an experimentally evolved Caenorhabditis elegans population.

Selfish mitochondrial DNA (mtDNA) mutations are variants that can proliferate within cells and enjoy a replication or transmission bias without fitness benefits for the host. mtDNA deletions in Caenorhabditis elegans can reach high heteroplasmic frequencies despite significantly reducing fitness, illustrating how new mtDNA variants can give rise to genetic conflict between different levels of selection and between the nuclear and mitochondrial genomes. During a mutation accumulation experiment in C.

Articular Cartilage- and Synoviocyte-Binding Poly(ethylene glycol) Nanocomposite Microgels as Intra-Articular Drug Delivery Vehicles for the Treatment of Osteoarthritis.

Intra-articular (IA) injection is an attractive route of administration for the treatment of osteoarthritis (OA). However, free drugs injected into the joint space are rapidly cleared and many of them can induce adverse off-target effects on different IA tissues. To overcome these limitations, we designed nanocomposite 4-arm-poly(ethylene glycol)-maleimide (PEG-4MAL) microgels, presenting cartilage- or synoviocyte-binding peptides, containing poly(lactic--glycolic) acid (PLGA) nanoparticles (NPs) as an IA small molecule drug delivery system.