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A subpopulation of human lymphoid cells called natural killers is able to lyse certain normal and neoplastic targets in an in vitro cytotoxicity assay. The molecules which enable them to recognize sensitive cells, or permit turnout cells to escape remain unknown. In the studies described here we have compared some of the plasma membrane characteristics of a NK-sensitive human leukaemia cell line (K562) with those of a partially resistant subclone derived from it (K562-Clone I). Gel electrophoresis of cell-surface proteins radiolabelled by lactoperoxidase-catalysed iodination, periodate-borohydride tritiation, or biosynthetically by incubation with [3H]fucose did not reveal any reproducible differences between the sensitive and resistant lines. However, analysis of glycolipids showed that Clone I incorporated significantly more fucose than did the parental line, and that it synthesized a minor population of complex structures not found in the original K562. A subclone of Clone I(Clone I-Con ArI), made resistant to the toxic effects of concanavalin A, became sensitive once again to NK, and showed the parental glycolipid profile. These results suggest that the Clone I line, selected for resistance to NK, may have altered one or more of its intermediate oligosaccharides or pathways of fucose incorporation into glycolipid, and points to one process by which a tumour cell might modulate its surface to escape recognition by natural killers. [ABSTRACT FROM AUTHOR]

Each year, unwanted plant pests and diseases, such as Hendel or potato soft rot, cause damage to crops and ecosystems all over the world. To continue to feed the growing population and protect the global ecosystems, the surveillance and management of the spread of these pests and diseases are crucial. Traditional methods of detection are often expensive, bulky and require expertise and training. Therefore, inexpensive, portable, and user-friendly methods are required. These include the use of different gas-sensing technologies to exploit volatile organic compounds released by plants under stress. These methods often meet these requirements, although they come with their own set of advantages and disadvantages, including the sheer number of variables that affect the profile of volatile organic compounds released, such as sensitivity to environmental factors and availability of soil nutrients or water, and sensor drift. Furthermore, most of these methods lack research on their use under field conditions. More research is needed to overcome these disadvantages and further understand the feasibility of the use of these methods under field conditions. This paper focuses on applications of different gas-sensing technologies from over the past decade to detect plant pests and diseases more efficiently.

This global study, which has been coordinated by the World Meteorological Organization Global Atmospheric Watch (WMO/GAW) programme, aims to understand the behaviour of key air pollutant species during the COVID-19 pandemic period of exceptionally low emissions across the globe. We investigated the effects of the differences in both emissions and regional and local meteorology in 2020 compared with the period 2015-2019. By adopting a globally consistent approach, this comprehensive observational analysis focuses on changes in air quality in and around cities across the globe for the following air pollutants PM 2.5 , PM 10 , PMC (coarse fraction of PM), NO 2 , SO 2 , NOx, CO, O 3 and the total gaseous oxidant (OX = NO 2  + O 3 ) during the pre-lockdown, partial lockdown, full lockdown and two relaxation periods spanning from January to September 2020. The analysis is based on in situ ground-based air quality observations at over 540 traffic, background and rural stations, from 63 cities and covering 25 countries over seven geographical regions of the world. Anomalies in the air pollutant concentrations (increases or decreases during 2020 periods compared to equivalent 2015-2019 periods) were calculated and the possible effects of meteorological conditions were analysed by computing anomalies from ERA5 reanalyses and local observations for these periods. We observed a positive correlation between the reductions in NO 2 and NOx concentrations and peoples' mobility for most cities. A correlation between PMC and mobility changes was also seen for some Asian and South American cities. A clear signal was not observed for other pollutants, suggesting that sources besides vehicular emissions also substantially contributed to the change in air quality. As a global and regional overview of the changes in ambient concentrations of key air quality species, we observed decreases of up to about 70% in mean NO 2 and between 30% and 40% in mean PM 2.5 concentrations over 2020 full lockdown compared to the same period in 2015-2019. However, PM 2.5 exhibited complex signals, even within the same region, with increases in some Spanish cities, attributed mainly to the long-range transport of African dust and/or biomass burning (corroborated with the analysis of NO 2 /CO ratio). Some Chinese cities showed similar increases in PM 2.5 during the lockdown periods, but in this case, it was likely due to secondary PM formation. Changes in O 3 concentrations were highly heterogeneous, with no overall change or small increases (as in the case of Europe), and positive anomalies of 25% and 30% in East Asia and South America, respectively, with Colombia showing the largest positive anomaly of ~70%. The SO 2 anomalies were negative for 2020 compared to 2015-2019 (between ~25 to 60%) for all regions. For CO, negative anomalies were observed for all regions with the largest decrease for South America of up to ~40%. The NO 2 /CO ratio indicated that specific sites (such as those in Spanish cities) were affected by biomass burning plumes, which outweighed the NO 2 decrease due to the general reduction in mobility (ratio of ~60%). Analysis of the total oxidant (OX = NO 2  + O 3 ) showed that primary NO 2 emissions at urban locations were greater than the O 3 production, whereas at background sites, OX was mostly driven by the regional contributions rather than local NO 2 and O 3 concentrations. The present study clearly highlights the importance of meteorology and episodic contributions (e.g., from dust, domestic, agricultural biomass burning and crop fertilizing) when analysing air quality in and around cities even during large emissions reductions. There is still the need to better understand how the chemical responses of secondary pollutants to emission change under complex meteorological conditions, along with climate change and socio-economic drivers may affect future air quality. The implications for regional and global policies are also significant, as our study clearly indicates that PM 2.5 concentrations would not likely meet the World Health Organization guidelines in many parts of the world, despite the drastic reductions in mobility. Consequently, revisions of air quality regulation (e.g., the Gothenburg Protocol) with more ambitious targets that are specific to the different regions of the world may well be required., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: The vast majority of adolescent mental health and substance use disorders go undiagnosed and undertreated. SMS text messaging is increasingly used as a method to deliver adolescent health services that promote psychological well-being and aim to protect adolescents from adverse experiences and risk factors critical for their current and future mental health. To date, there has been no comprehensive synthesis of the existing literature on the extent, range, and implementation contexts of these SMS text message interventions., Objective: The objective of this scoping review was to map and categorize gaps in the current body of peer-reviewed research around the use of SMS text messaging-based interventions for mental health and addiction services among adolescents., Methods: A scoping review was conducted according to Levac's adaptation of Arksey and O'Malley's methodological framework for scoping reviews in six iterative stages. A search strategy was cocreated and adapted for five unique databases. Studies were screened using Covidence software. The PICO (patient, intervention, comparator, outcome) framework and input from multiple stakeholder groups were used to structure and pilot a data extraction codebook. Data were extracted on study methodology and measures, intervention design, and implementation characteristics, as well as policy, practice, and research implications., Results: We screened 1142 abstracts. Of these, 31 articles published between 2013 and 2020 were eligible for inclusion. Intervention engagement was the most common type of outcome measured (18/31), followed by changes in cognitions (16/31; eg, disease knowledge, self-awareness) and acceptability (16/31). Interventions were typically delivered in less than 12 weeks, and adolescents received 1-3 messages per week. Bidirectional messaging was involved in 65% (20/31) of the studies. Limited descriptions of implementation features (eg, cost, policy implications, technology performance) were reported., Conclusions: The use of SMS text messaging interventions is a rapidly expanding area of research. However, lack of large-scale controlled trials and theoretically driven intervention designs limits generalizability. Significant gaps in the literature were observed in relation to implementation considerations, cost, clinical workflow, bidirectionality of texting, and level of personalization and tailoring of the interventions. Given the growth of mobile phone-based interventions for this population, a rigorous program of large-scale, well-designed trials is urgently required., (©Sarah MacDougall, Susan Jerrott, Sharon Clark, Leslie Anne Campbell, Andrea Murphy, Lori Wozney. Originally published in JMIR Mental Health (http://mental.jmir.org), 08.01.2021.)

The treatment of diseased vasculature remains challenging, in part because of the difficulty in implanting drug-eluting devices without subjecting vessels to damaging mechanical forces. Implanting materials using adhesive forces could overcome this challenge, but materials have previously not been shown to durably adhere to intact endothelium under blood flow. Marine mussels secrete strong underwater adhesives that have been mimicked in synthetic systems. Here we develop a drug-eluting bioadhesive gel that can be locally and durably glued onto the inside surface of blood vessels. In a mouse model of atherosclerosis, inflamed plaques treated with steroid-eluting adhesive gels had reduced macrophage content and developed protective fibrous caps covering the plaque core. Treatment also lowered plasma cytokine levels and biomarkers of inflammation in the plaque. The drug-eluting devices developed here provide a general strategy for implanting therapeutics in the vasculature using adhesive forces and could potentially be used to stabilize rupture-prone plaques.

Objective: To examine the effects of advanced access (same-day physician appointments) on patient and provider satisfaction and to determine its association with other variables such as physician income and patient emergency department use., Design: Patient satisfaction survey and semistructured interviews with physicians and support staff; analysis of physician medical insurance billings and patient emergency department visits., Setting: Cape Breton, NS., Participants: Patients, physicians, and support staff of 3 comparable family physician practices that had not implemented advanced access and an established advanced access practice., Main Outcome Measures: Self-reported provider and patient satisfaction, physician office income, and patients' emergency department use., Results: The key benefits of implementation of advanced access were an increase in provider and patient satisfaction levels, same or greater physician office income, and fewer less urgent (triage level 4) and nonurgent (triage level 5) emergency department visits by patients., Conclusion: Currently within the Central Cape Breton Region, 33% of patients wait 4 or more days for urgent appointments. Findings from this study can be used to enhance primary care physician practice redesign. This research supports many benefits of transitioning to an advanced access model of patient booking.

This article reports the development and validation of a measure of Irrational Food Beliefs (IFB), defined as cognitively distorted and unhealthy attitudes and beliefs pertaining to food, which is proposed to be a factor that undermines success at weight loss and maintenance. Studies 1 and 2 demonstrated that the Irrational Food Beliefs Scale (IFBS) contains ecologically valid items and is comprised of two primary factors (irrational and rational food beliefs) whose items are internally consistent. Study 3 established that irrational subscale scores were positively associated with first semester weight gain in college freshmen. In Study 4, irrational food belief scores related predictably to measures of recent weight gain, poor weight loss maintenance, and bulimic symptoms in another college sample. In addition, IFB scores were not unduly influenced by test-taking response sets, and they were positively associated with depression and phobic anxiety and negatively correlated with self-esteem and need for cognition. Study 5 revealed strong positive associations between irrational food beliefs and bulimic symptoms, as well as number of previous diets in an obese community sample. The role irrational food beliefs may play in poor weight loss outcomes and maintenance is discussed.

Clear boundaries between physicians and patients help prevent abusive behaviour. Enforced boundaries help physicians fulfil their legal, ethical, and professional tasks. We review common elements in boundary violations: role reversal, secrecy, double binds, and indulgence of professional privilege. We also outline the legal and licensing issues of boundary violations and offer examples of nine boundaries.

The activity of natural killer (NK) cells can be augmented by incubation with interferons, or with other compounds, such as staphylococcal protein A, which stimulate interferon production. In the experiments described here we compared the patterns of lytic activity of human lymphoid effector cells, before (NK-B) and after (NK-A) short-term activation. Target cells used were K562, Clone I (a partially NK-resistant K562 variant), and those that had been preincubated with neuraminidase or trypsin. The results obtained include the following: proteases, but not neuraminidase, decreased lysis by NK-B, but not by NK-A, of both K562 and Clone I in the standard Cr-release assay. In the single cell assay, trypsin minimally decreased conjugate formation and the fraction of bound cells that were killed by NK-B, but did not reverse the increased lytic efficiency of NK-A. In the cold-target competition assay, Clone I, which does not compete as well with K562 for NK-B, did so equally well for NK-A. Trypsinized targets, regardless of their equal sensitivity to lysis by NK-A, were not as active competitors for NK-A. We conclude that the most reasonable interpretation is that K562 cells bear surface structures which can induce release of lytic mediators from NK-A under conditions that are not sufficient to stimulate NK-B. Although it appears that NK-A may respond to a smaller number of the same target molecules recognized by NK-B, the process must be better defined at the molecular level to exclude the possibility that there are qualitative differences between the proposed recognition structures for these two states of NK activity.

By depletion of effector-target conjugates and cloning, a variant of the human leukemic line K562 that is partially resistant to lysis by natural killer (NK) cells when tested under conditions of culture and assay identical to that of the parent has been derived. Its karyotype shows markers similar to the original K562. The resistant phenotype remains stable after over 1 year of continuous passage and persists in multiple replicate subclones. However, it can be killed to a degree equal to the parent by antibody-activated complement, antibody-dependent cellular mechanisms, and by effector cells activated by staphylococcal protein A. These observations and experiments on cold target competition suggest that on its surface there is a significantly decreased, absent, or blocked effective target structure for a major population of unstimulated peripheral blood NK cells.