Characterization of intrinsic and effective fitness changes caused by temporarily fixed mutations in the SARS-CoV-2 spike E484 epitope and identification of an epistatic precondition for the evolution of E484A in variant Omicron.

Background: Intrinsic fitness costs are likely to have guided the selection of lineage-determining mutations during emergence of variants of SARS-CoV-2. Whereas changes in receptor affinity and antibody neutralization have been thoroughly mapped for individual mutations in spike, their influence on intrinsic replicative fitness remains understudied.

Methods: We analyzed mutations in immunodominant spike epitope E484 that became temporarily fixed over the pandemic.

Effects of AFQ056 on language learning in fragile X syndrome.

BACKGROUNDFXLEARN, the first-ever large multisite trial of effects of disease-targeted pharmacotherapy on learning, was designed to explore a paradigm for measuring effects of mechanism-targeted treatment in fragile X syndrome (FXS). In FXLEARN, the effects of metabotropic glutamate receptor type 5 (mGluR5) negative allosteric modulator (NAM) AFQ056 on language learning were evaluated in 3- to 6-year-old children with FXS, expected to have more learning plasticity than adults, for whom prior trials of mGluR5 NAMs have failed.METHODSAfter a 4-month single-blind placebo lead-in, participants were randomized 1:1 to AFQ056 or placebo, with 2 months of dose optimization to the maximum tolerated dose, then 6 months of treatment during which a language-learning intervention was implemented for both groups.

Low Risk Profile of Long-Term Repeated Lumbar Puncture for Intrathecal Delivery of 2-Hydroxypropyl-Beta-Cyclodextrin in Patients With Niemann-Pick Type C.

Background: Intrathecal delivery of 2-hydroxypropyl-beta-cyclodextrin (VTS-270, adrabetadex) by lumbar puncture (LP) has been performed on a biweekly schedule for over nine years for the treatment of Niemann-Pick type C1 (NPC1) at Rush University Medical Center.

Methods: Over this time 59 patients with NPC1 have been treated with 2935 infusions, performed with either a 22-G 3-inch Whitacre or a 22-G 2-inch Gertie Marx atraumatic needles, with or without general anesthesia. Adverse events potentially related to the LP infusion were collected from records for all patients treated for NPC.

Interdependence of sequential cytotoxic T lymphocyte and natural killer cell cytotoxicity against melanoma cells.

Cytotoxic T lymphocytes (CTL) and natural killer (NK) cells recognize and eliminate cancer cells. However, immune evasion, downregulation of immune function by the tumour microenvironment and resistance of cancer cells are major problems. Although CTL and NK cells are both important to eliminate cancer, most studies address them individually.