Workplace challenges, supports, and accommodations for people with inflammatory bowel disease: a scoping review.

PURPOSE: To characterize the breadth of challenges that people with IBD experience in the workplace and identify supports and accommodations that can help sustain employment. MATERIALS AND METHODS: A scoping review was conducted using the Arksey and O'Malley framework. Electronic databases (MEDLINE, PsycINFO, CINAHL, EMBASE) and grey literature websites identified English-language studies published from inception through to June 2020. Studies where details were insufficient to extract the study purpose, sample, methods, and findings were deemed of poorer quality and excluded. RESULTS: Eighteen studies met selection criteria. Studies discussed common workplace challenges, including career planning, work performance, managing physical and cognitive symptoms, social impacts at work, and challenges related to the physical work environment and commuting. The range of workplace supports identified by studies was classified into five categories: flexibility, changes to the physical work environment, social support, self-management strategies, and extended health benefits. CONCLUSIONS: IBD research typically has been descriptive and focused on broad characterizations of workplace challenges and supports. Future work needs to examine causal pathways and assess the efficacy of workplace supports, as well as conduct subgroup analyses and develop resources to facilitate communication and accommodation planning between workers living with IBD and their employers.Implications for RehabilitationRehabilitation professionals can play an important role in supporting people working with inflammatory bowel disease (IBD) by identifying accommodations and ways to make work environments more supportive.Providing rehabilitation support to people with IBD goes beyond symptom management and needs to consider the broader social, policy, and environmental challenges of employment.

Characterization of the B6.61 polymerase ribozyme accessory domain.

The "RNA world" hypothesis rests on the assumption that RNA polymerase ribozymes can replicate RNA without the use of protein. In the laboratory, in vitro selection has been used to create primitive versions of such polymerases. The best variant to date is a ribozyme called B6.61 that can extend a RNA primer template by 20 nucleotides (nt). This polymerase has two domains: the recently crystallized Class I ligase core, responsible for phosphodiester bond formation, and the poorly characterized accessory domain that makes polymerization possible. Here we find that the accessory domain is specified by a 37-nt bulged stem-loop structure. The accessory domain is positioned by a tertiary interaction between the terminal AL4 loop of the accessory and the J3/4 triloop found within the ligase core. This docking interaction is associated with an unwinding of the A3 and A4 helixes that appear to facilitate the correct positioning of an essential 8-nt purine bulge found between the two helices. This, together with other constraints inferred from tethering the accessory domain to a range of sites on the ligase core, indicates that the accessory domain is draped over the vertex of the ligase core tripod structure. This geometry suggests how the purine bulge in the polymerase replaces the P2 helix in the Class I ligase with a new structure that may facilitate the stabilization of incoming nucleotide triphosphates.

Closing the circle: replicating RNA with RNA.

How life emerged on this planet is one of the most important and fundamental questions of science. Although nearly all details concerning our origins have been lost in the depths of time, there is compelling evidence to suggest that the earliest life might have exploited the catalytic and self-recognition properties of RNA to survive. If an RNA based replicating system could be constructed in the laboratory, it would be much easier to understand the challenges associated with the very earliest steps in evolution and provide important insight into the establishment of the complex metabolic systems that now dominate this planet. Recent progress into the selection and characterization of ribozymes that promote nucleotide synthesis and RNA polymerization are discussed and outstanding problems in the field of RNA-mediated RNA replication are summarized.