Impact of the COVID-19 pandemic on delivery of prostate cancer care in Australia: An interrupted time series analysis.

The COVID-19 pandemic led to a major disruption to health services across the world. The aim of this population-based study was to assess the downstream effects of the pandemic on diagnostic tests and treatment activities related to prostate cancer (PC). The Australian Government Department of Health Medicare Benefits Schedule and the Pharmaceutical Benefits Scheme databases were queried from January 2010 to June 2022. Two interrupted time series were performed Pre-COVID (January 2010 to February 2020) and peri-COVID (March 2020 to June 2022). Temporal modeling was performed to account for seasonal variation. Pre-COVID-19, monthly prostate-specific antigen (PSA) testing showed a declining trend and testing decreased by 81 tests per 100 000 annually. A single-month 38% drop in PSA testing was observed in April 2020; this corresponded to Australia's first wave. No change was observed in the rate of prostate biopsies. Peri-COVID-19 outbreaks, there was a slight shift toward the use of long-acting androgen deprivation therapy (ADT) at 4% with a predilection still for short-acting agents. with no registered change in the overall volume of radiotherapy or surgery. There were no deficits in the number of diagnostic and treatment activities for men with PC. Aside from a slight shift toward long-acting ADT use during the pandemic, no other patterns were observed. The longer-term impact such as missed diagnosis or late presentation affecting chances of survival due to COVID-19 is yet to be ascertained.

Probing the interaction of archaeal DNA polymerases with deaminated bases using X-ray crystallography and non-hydrogen bonding isosteric base analogues.

Archaeal family-B DNA polymerases stall replication on encountering the pro-mutagenic bases uracil and hypoxanthine. This publication describes an X-ray crystal structure of Thermococcus gorgonarius polymerase in complex with a DNA containing hypoxanthine in the single-stranded region of the template, two bases ahead of the primer-template junction. Full details of the specific recognition of hypoxanthine are revealed, allowing a comparison with published data that describe uracil binding. The two bases are recognized by the same pocket, in the N-terminal domain, and make very similar protein-DNA interactions. Specificity for hypoxanthine (and uracil) arises from a combination of polymerase-base hydrogen bonds and shape fit between the deaminated bases and the pocket. The structure with hypoxanthine at position 2 explains the stimulation of the polymerase 3'-5' proofreading exonuclease, observed with deaminated bases at this location. A beta-hairpin element, involved in partitioning the primer strand between the polymerase and exonuclease active sites, inserts between the two template bases at the extreme end of the double-stranded DNA. This denatures the two complementary primer bases and directs the resulting 3' single-stranded extension toward the exonuclease active site. Finally, the relative importance of hydrogen bonding and shape fit in determining selectivity for deaminated bases has been examined using nonpolar isosteres. Affinity for both 2,4-difluorobenzene and fluorobenzimidazole, non-hydrogen bonding shape mimics of uracil and hypoxanthine, respectively, is strongly diminished, suggesting polar protein-base contacts are important. However, residual interaction with 2,4-difluorobenzene is seen, confirming a role for shape recognition.