CHIEF: A retrospective self-control study of children with severe hemophilia A without inhibitors comparing emicizumab to FVIII prophylaxis.

Background: Hemophilia A (HA) is an X-linked bleeding disorder diagnosed by a deficiency in factor VIII (FVIII). For severe HA (SHA), prophylaxis clotting factor concentrates (CFC) has become the standard of care; however, it imparts a high treatment burden and typically results in an annualized bleeding rate (ABR) of 2-6. Emicizumab, a subcutaneously administered FVIII substitute, has become the de facto standard-of-care prophylaxis for children with SHA in many countries.

The antiretroviral agents azidothymidine, stavudine, and didanosine have the identical mutational fingerprint in the rpoB region of Escherichia coli.

We looked at the mutational fingerprints of three antiretroviral (anti-HIV) agents, azidothymidine (AZT), stavudine (STAV), and didanosine (DIDA) in the rpoB system of Escherichia coli and compared them with each other and with the fingerprints of trimethoprim and of spontaneous mutations in a wild-type and a mutT background. All three agents gave virtually identical fingerprints in the wild-type background, causing only A:T→C:G changes at 3 of the 12 A:T→C:G possible sites among the total of 92 possible base substitution mutations, even though AZT and STAV are thymidine analogs but DIDA is an adenosine analog. As all three agents are reverse transcriptase inhibitors, and act as chain blockers, the common fingerprint may be a property of chain blocking agents.

Mutations induced by Bleomycin, 4-nitroquinoline-1-oxide, and hydrogen peroxide in the rpoB gene of Escherichia coli: Perspective on Mutational Hotspots.

We report the mutational spectra in a segment of the E. coli rpoB gene of bleomycin (BLEO), 4-nitroquinoline-1-oxide (NQO), and hydrogen peroxide (HO). We compare these spectra with those of other mutagens and repair deficient strains in the same rpoB system, and review the key elements determining mutational hotspots and outline the questions that remain unanswered.