Short RNA Guides Cleavage by Eukaryotic RNase III

In eukaryotes, short RNAs guide a variety of enzymatic activities that range from RNA editing to translation repression. It is hypothesized that pre-existing proteins evolved to bind and use guide RNA during evolution. However, the capacity of modern proteins to adopt new RNA guides has never been demonstrated. Here we show that Rnt1p, the yeast orthologue of the bacterial dsRNA-specific RNase III, can bind short RNA transcripts and use them as guides for sequence-specific cleavage. Target cleavage occurred at a constant distance from the Rnt1p binding site, leaving the guide RNA intact for subsequent cleavage. Our results indicate that RNase III may trigger sequence-specific RNA degradation independent of the RNAi machinery, and they open the road for a new generation of precise RNA silencing tools that do not trigger a dsRNA-mediated immune response

Nutrient scarcity as a selective pressure for mast seeding

Mast seeding is one of the most intriguing reproductive traits in nature. Despite its potential drawbacks in terms of fitness, the widespread existence of this phenomenon suggests that it should have evolutionary advantages under certain circumstances. Using a global dataset of seed production time series for 219 plant species from all the continents, we tested whether masting behaviour appears predominantly in species with low foliar N and P concentrations, when controlling for local climate and productivity. Here we show that masting intensity is higher in species with low foliar N and P concentrations and especially imbalanced N:P ratios, and that the evolutionary history of masting behaviour has been linked to that of nutrient economy. Our results support the hypothesis that masting is stronger in species growing under limiting conditions and suggest that this reproductive behaviour might have evolved as an adaptation to nutrient limitations and imbalances

HPV vaccination introduction worldwide and WHO and UNICEF estimates of national HPV immunization coverage 2010–2019

WHO/UNICEF estimates for HPV vaccination coverage from 2010 to 2019 are analyzed against the backdrop of the 90% coverage target for HPV vaccination by 2030 set in the recently approved global strategy for cervical cancer elimination as a public health problem. As of June 2020, 107 (55%) of the 194 WHO Member States have introduced HPV vaccination. The Americas and Europe are by far the WHO regions with the most introductions, 85% and 77% of their countries having already introduced respectively. A record number of introductions was observed in 2019, most of which in low- and middle- income countries (LMIC) where access has been limited. Programs had an average performance coverage of around 67% for the first dose and 53% for the final dose of HPV. LMICs performed on average better than high- income countries for the first dose, but worse for the last dose due to higher dropout. Only 5 (6%) countries achieved coverages with the final dose of more than 90%, 22 countries (21%) achieved coverages of 75% or higher while 35 (40%) had a final dose coverage of 50% or less. When expressed as world population coverage (i.e., weighted by population size), global coverage of the final HPV dose for 2019 is estimated at 15%. There is a long way to go to meet the 2030 elimination target of 90%. In the post-COVID era attention should be paid to maintain the pace of introductions, specially ensuring the most populous countries introduce, and further improving program performance globally

Low-value clinical practices in injury care: a scoping review and expert consultation survey

BACKGROUND: Tests and treatments that are not supported by evidence and could expose patients to unnecessary harm, referred to here as low-value clinical practices, consume up to 30% of healthcare resources. Choosing Wisely and other organisations have published lists of clinical practices to be avoided. However, few apply to injury and most are based uniquely on expert consensus. We aimed to identify low-value clinical practices in acute injury care. METHODS: We conducted a scoping review targeting articles, reviews and guidelines that identified low-value clinical practices specific to injury populations. Thirty-six experts rated clinical practices on a 5-point Likert scale from clearly low-value to clearly beneficial. Clinical practices reported as low-value by at least one level I, II or III study and considered clearly or potentially low-value by at least 75% of experts were retained as candidates for low-value injury care. RESULTS: Of 50,695 citations, 815 studies were included and led to the identification of 150 clinical practices. Of these 63 were considered candidates for low-value injury care; 33 in the emergency room, 9 in trauma surgery, 15 in the intensive care unit and 5 in orthopaedics. We also identified 87 'grey zone' practices, which did not meet our criteria for low-value care. CONCLUSIONS: We identified 63 low-value clinical practices in acute injury care that are supported by empirical evidence and expert opinion. Conditional on future research, they represent potential targets for guidelines, overuse metrics and de-implementation interventions. We also identified 87 'grey zone' practices, which may be interesting targets for value-based decision-making. Our study represents an important step towards the de-implementation of low-value clinical practices in injury care. LEVEL OF EVIDENCE: III

Small business owners' health and safety intentions: A cross-sectional survey

BACKGROUND: Little is known about the variables underlying small business owners' behavioural intentions toward workplace health and safety. This project explores the relationship between three mediating variables (Attitude Toward Safety, Subjective Norm and Perceived Behavioural Control) and owners' Intentions Toward Safety, following the Theory of Planned Behaviour. We also investigate the role of beliefs underlying each mediating variable. METHODS: Seven hundred businesses (5–50 employees) were randomly selected from 4084 eligible companies in a manufacturing business database (SIC codes 24 to 39). The 348 respondents are on average 51 yrs of age, 86% male, 96% white and have 2 to 4 years of post-secondary school. RESULTS: All three mediator variables are significantly correlated with Intentions Toward Safety; Attitude Toward Safety shows the strongest correlation, which is confirmed by path analysis. Owners with higher attitudes toward safety have a higher probability of believing that improving workplace health and safety will make employees' healthier and happier, show that they care, increase employee productivity, lower workers' compensation costs, increase product quality and lower costs. CONCLUSION: These results suggest that interventions aimed at increasing owners' health and safety intentions (and thus, behaviours) should focus on demonstrating positive employee health and product quality outcomes

Changes in microphytobenthos fluorescence over a tidal cycle: implications for sampling designs

Intertidal microphytobenthos (MPB) are important primary producers and provide food for herbivores in soft sediments and on rocky shores. Methods of measuring MPB biomass that do not depend on the time of collection relative to the time of day or tidal conditions are important in any studies that need to compare temporal or spatial variation, effects of abiotic factors or activity of grazers. Pulse amplitude modulated (PAM) fluorometry is often used to estimate biomass of MPB because it is a rapid, non-destructive method, but it is not known how measures of fluorescence are altered by changing conditions during a period of low tide. We investigated this experimentally using in situ changes in minimal fluorescence (F) on a rocky shore and on an estuarine mudflat around Sydney (Australia), during low tides. On rocky shores, the time when samples are taken during low tide had little direct influence on measures of fluorescence as long as the substratum is dry. Wetness from wave-splash, seepage from rock pools, run-off, rainfall, etc., had large consequences for any comparisons. On soft sediments, fluorescence was decreased if the sediment dried out, as happens during low-spring tides on particularly hot and dry days. Surface water affected the response of PAM and therefore measurements used to estimate MPB, emphasising the need for care to ensure that representative sampling is done during low tide

Intraspecific Variation in Pinus Pinaster PSII Photochemical Efficiency in Response to Winter Stress and Freezing Temperatures

As part of a program to select maritime pine (Pinus pinaster Ait.) genotypes for resistance to low winter temperatures, we examined variation in photosystem II activity by chlorophyll fluorescence. Populations and families within populations from contrasting climates were tested during two consecutive winters through two progeny trials, one located at a continental and xeric site and one at a mesic site with Atlantic influence. We also obtained the LT50, or the temperature that causes 50% damage, by controlled freezing and the subsequent analysis of chlorophyll fluorescence in needles and stems that were collected from populations at the continental trial site