RESUMEN
Arenaviruses can cause severe haemorrhagic fever and neurological diseases in humans and other animals, exemplified by Lassa mammarenavirus, Machupo mammarenavirus and lymphocytic choriomeningitis virus, posing great threats to public health1-4. These viruses encode a large multi-domain RNA-dependent RNA polymerase for transcription and replication of the viral genome5. Viral polymerases are one of the leading antiviral therapeutic targets. However, the structure of arenavirus polymerase is not yet known. Here we report the near-atomic resolution structures of Lassa and Machupo virus polymerases in both apo and promoter-bound forms. These structures display a similar overall architecture to influenza virus and bunyavirus polymerases but possess unique local features, including an arenavirus-specific insertion domain that regulates the polymerase activity. Notably, the ordered active site of arenavirus polymerase is inherently switched on, without the requirement for allosteric activation by 5'-viral RNA, which is a necessity for both influenza virus and bunyavirus polymerases6,7. Moreover, dimerization could facilitate the polymerase activity. These findings advance our understanding of the mechanism of arenavirus replication and provide an important basis for developing antiviral therapeutics.
Asunto(s)
Arenavirus del Nuevo Mundo/enzimología , Microscopía por Crioelectrón , Virus Lassa/enzimología , ARN Polimerasa Dependiente del ARN/química , ARN Polimerasa Dependiente del ARN/ultraestructura , Replicación Viral , Apoenzimas/química , Apoenzimas/metabolismo , Apoenzimas/ultraestructura , Arenavirus del Nuevo Mundo/ultraestructura , Dominio Catalítico , Virus Lassa/ultraestructura , Virus de la Coriomeningitis Linfocítica/enzimología , Virus de la Coriomeningitis Linfocítica/ultraestructura , Modelos Moleculares , Regiones Promotoras Genéticas/genética , ARN Polimerasa Dependiente del ARN/metabolismoRESUMEN
Robotic surgical systems are relatively new in New Zealand and have been used mainly for laparoscopic radical prostatectomy. Checklists are successfully used in other industries and health care facilities, so we developed a checklist for use during robotic-assisted laparoscopic radical prostatectomy (RALRP) procedures. After a two-month trial using the checklist, we calculated the completeness of each phase of the checklist as a percentage of the number of completed checklists versus total number of compliant checklists in that phase. Operating room personnel participated in an audiotaped focus group and discussed their perceptions about using the RALRP checklist. We collected, transcribed, and reviewed the focus group discussion and thematically analyzed the responses, which confirmed that the checklist served as a guideline and reminder during the setup. Additionally, staff members associated the checklist with improved OR readiness, minimized workflow interruption, improved efficiency, and positive changes in confidence and teamwork.