Summary Background A high-dose trivalent inactivated influenza vaccine was licensed in 2009 by the US Food and Drug Administration (FDA) on the basis of serological criteria. We sought to establish whether high-dose inactivated influenza vaccine was more effective for prevention of influenza-related visits and hospital admissions in US Medicare beneficiaries than was standard-dose inactivated influenza vaccine. Methods In this retrospective cohort study, we identified Medicare beneficiaries aged 65 years and older who received high-dose or standard-dose inactivated influenza vaccines from community pharmacies that offered both vaccines during the 2012–13 influenza season. Outcomes were defined with billing codes on Medicare claims. The primary outcome was probable influenza infection, defined by receipt of a rapid influenza test followed by dispensing of the neuraminidase inhibitor oseltamivir. The secondary outcome was a hospital or emergency department visit, listing a Medicare billing code for influenza. We estimated relative vaccine effectiveness by comparing outcome rates in Medicare beneficiaries during periods of high influenza circulation. Univariate and multivariate Poisson regression models were used for analyses. Findings Between Aug 1, 2012 and Jan 31, 2013, we studied 929 730 recipients of high-dose vaccine and 1 615 545 recipients of standard-dose vaccine. Participants enrolled in each cohort were well balanced with respect to age and presence of underlying medical disorders. The high-dose vaccine (1·30 outcomes per 10 000 person-weeks) was 22% (95% CI 15–29) more effective than the standard-dose vaccine (1·01 outcomes per 10 000 person-weeks) for prevention of probable influenza infections (rapid influenza test followed by oseltamivir treatment) and 22% (95% CI 16–27%) more effective for prevention of influenza hospital admissions (0·86 outcomes per 10 000 person-weeks in the high-dose cohort vs 1·10 outcomes per 10 000 person-weeks in the standard-dose cohort). Interpretation Our retrospective cohort study in US Medicare beneficiaries shows that, in people 65 years of age and older, high-dose inactivated influenza vaccine was significantly more effective than standard-dose vaccine in prevention of influenza-related medical encounters. Additionally, the large population in our study enabled us to show, for the first time, a significant reduction in influenza-related hospital admissions in high-dose compared to standard-dose vaccine recipients, an outcome not shown in randomised studies. These results provide important new information to be considered by policy makers recommending influenza vaccinations for elderly people. Funding FDA and the office of the Assistant Secretary of Planning and Evaluation.

From early detection of variants of concern to vaccine and therapeutic design, pandemic preparedness depends on identifying viral mutations that escape the response of the host immune system. While experimental scans are useful for quantifying escape potential, they remain laborious and impractical for exploring the combinatorial space of mutations. Here we introduce a biologically grounded model to quantify the viral escape potential of mutations at scale. Our method - EVEscape - brings together fitness predictions from evolutionary models, structure-based features that assess antibody binding potential, and distances between mutated and wild-type residues. Unlike other models that predict variants of concern based on newly observed variants, EVEscape has no reliance on recent community prevalence, and is applicable before surveillance sequencing or experimental scans are broadly available. We validate EVEscape predictions against experimental data on H1N1, HIV and SARS-CoV-2, including data on immune escape. For SARS-CoV-2, we show that EVEscape anticipates mutation frequency, strain prevalence, and escape mutations. Drawing from GISAID, we provide continually updated escape predictions for all current strains of SARS-CoV-2.

Biocomputing nanoplatforms are designed to detect and integrate single or multiple inputs under defined algorithms, such as Boolean logic gates, and generate functionally useful outputs, such as delivery of therapeutics or release of optically detectable signals. Using sensing modules composed of small molecules, polymers, nucleic acids, or proteins/peptides, nanoplatforms have been programmed to detect and process extrinsic stimuli, such as magnetic fields or light, or intrinsic stimuli, such as nucleic acids, enzymes, or pH. Stimulus detection can be transduced by the nanomaterial via three different mechanisms: system assembly, system disassembly, or system transformation. The increasingly sophisticated suite of biocomputing nanoplatforms may be invaluable for a multitude of applications, including medical diagnostics, biomedical imaging, environmental monitoring, and delivery of therapeutics to target cell populations.

Ru and Ru x Ni 30 dendrimer encapsulated nanoparticles (DENs) were synthesized using a redox-displacement method. DEN catalytic activity for the reduction of p-nitrophenol was evaluated and found to be dependent on the ratio of metals present.Dendrimer-templated nanoparticle synthesis is an efficient method for preparing a variety of mono-and bimetallic nanomaterials, whose sizes are constrained by the loading capacity of the dendrimer template.1,2 A common commercially available dendrimer is composed of repeating amino-amide units (polyamidoamine, PAMAM), whose internal amines coordinate with free metal ions in solution.3 The metal ion affinity for these amine groups strongly influences their partitioning into the dendrimer interior; metal ions such as Cu 2+ and Pd 2+ will readily complex within dendrimers under the appropriate conditions and may be directly reduced to metal nanoparticles. 4,5 However, weakly coordinating metal ions require either a dendrimer template with more appropriate interior groups for coordinating metal cations, which may not be readily available, or an indirect synthetic route. Intradendrimer redox displacement, which involves the formation of dendrimer encapsulated nanoparticles (DENs) of one metal followed by exchange for a second, more noble metal, has been previously reported.6 Zhao et al. 6 synthesized Cu 55 DENs using generation 6, hydroxyl-terminated (G6-OH) PAMAM dendrimers. Here, we describe the preparation of ruthenium-nickel dendrimer encapsulated nanoparticles (RuNi DENs) in generation 4 hydroxylterminated (G4-OH) PAMAM dendrimers. Previously reported syntheses of Ru DENs used sodium borohydride (NaBH 4 ) 7 as well as H 2(g) 8 as reductants, following complexation of the Ru 3+ for 2-3 days. In this report, we investigated Ni as a potential partner in a displacement scheme to form Ru and RuNi DENs; the displacement was evaluated for 5-20 molar excess (ME) of Ru 3+ and Ni 2+ , and the resulting effects on the DEN catalytic efficiency for a model reduction reaction were evaluated. This method of preparation eliminates significant metal ion complexation time and results in RuNi DENs that are stable for at least a week under an inert atmosphere.The galvanic displacement of Ni 0 with Ru 0 is based on the following set of half-reactions:During synthesis, 30 ME of Ni(NO 3 ) 2 was added to a 10 mM aqueous solution of G4-OH PAMAM dendrimer at pH B5 and placed on a VWR nutating mixer. After 60-90 min, the UV-Visible absorption spectrum showed a very weak band at 272 nm and no bands associated with Ni 2+ in solution, indicating that (Ni 2+ ) 30 was complexed within the dendrimer interior (Fig. 1A). After purging with Ar (g) for 20 min, the solution was reduced with 5 ME of NaBH 4 ; the colorless solution turned translucent brown, the spectrum shifted upward, and the distinctive peak at 272 nm flattened. The solution pH was adjusted to r 8 using B0.010 mL (per mL of solution) of 0.10 M HCl via a gas-tight syringe; the approximate solution pH was checked using pHydrion paper. The soluti...