pinboard August 17, 2021

  • Britain’s Idyllic Country Houses Reveal a Darker History
    Great estates are among the country’s treasures. But their connections to slavery and colonialism are forcing visitors to reckon with myths they may not want to abandon.
  • Dynamics of SARS-CoV-2 Spike Proteins in Cell Entry: Control Elements in the Amino-Terminal Domains | mBio
    Selective pressures drive adaptive changes in the coronavirus spike proteins directing virus-cell entry. These changes are concentrated in the amino-terminal domains (NTDs) and the receptor-binding domains (RBDs) of complex modular spike protein trimers. The impact of this hypervariability on virus entry is often unclear, particularly with respect to sarbecovirus NTD variations. Therefore, we constructed indels and substitutions within hypervariable NTD regions and used severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus-like particles and quantitative virus-cell entry assays to elucidate spike structures controlling this initial infection stage. We identified NTD variations that increased SARS-CoV-2 spike protein-mediated membrane fusion and cell entry. Increased cell entry correlated with greater presentation of RBDs to ACE2 receptors. This revealed a significant allosteric effect, in that changes within the NTDs can orient RBDs for effective virus-cell binding. Yet, those NTD changes elevating receptor binding and membrane fusion also reduced interdomain associations, leaving spikes on virus-like particles susceptible to irreversible inactivation. These findings parallel those obtained decades ago, in which comparisons of murine coronavirus spike protein variants established inverse relationships between membrane fusion potential and virus stability. Considerable hypervariability in the SARS-CoV-2 spike protein NTDs also appear to be driven by counterbalancing pressures for effective virus-cell entry and durable extracellular virus infectivity. These forces may
  • The Messiest Phase of the Pandemic Yet
    Coronavirus data have always been incomplete—but the situation in America is particularly murky now.
  • Parting Stone® solidified remains | A Clean Alternative to Ashes
    Solidified remains open a gateway to healing and growth. Start the process today and hold the remains of your loved one close. No more uncomfortable ash.
  • Zometa ® – Chemotherapy Drugs – Chemocare
    Zoledronic acid is used as a support medication to treat symptoms of cancer such as hypercalcemia (high blood calcium levels) or to decrease complications (such as fractures or pain) produced by bone metastasis (spread of cancer to the bone).
  • Chasing the Lava Flow in Iceland — The New Yorker
    At a volcanic eruption, the sublime experience of watching land submerge land.

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