Why current-carrying magnetic flux tubes gobble up plasma and become thin as a result

It is shown that if a current-carrying magnetic flux tube is bulged at its axial midpoint z=0 and constricted at its axial endpoints z=+h,-h, then plasma will be accelerated from z=+h,-h towards z=0 resulting in a situation similar to two water jets pointed at each other. The ingested plasma convects embedded, frozen-in toroidal magnetic flux from z=+h,-h to z=0. The counter-directed flows collide and stagnate at z=0 and in so doing (i) convert their translational kinetic energy into heat, (ii) increase the plasma density at z~0, and (iii) increase the embedded toroidal flux density at z~0. The increase in toroidal flux density at z~0 increases the toroidal field Bphi and hence increases the magnetic pinch force at z~0 and so causes a reduction of the flux tube radius at z~0. Thus, the flux tube develops an axially uniform cross-section, a decreased volume, an increased density, and an increased temperature. This model is proposed as a likely hypothesis for the long-standing mystery of why solar coronal loops are observed to be axially uniform, hot, and bright.Comment: to appear in Physics of Plasmas 24 pages, 5 figure

Fluoroquinolone-associated tendinopathy: a case report

Fluoroquinolone-associated tendinopathy is well described. This adverse effect however does not appear to be widely known among medical practitioners. We hereby described a case of ciprofloxacin-associated tendinopathy for which the adverse drug reaction was not suspected initially and the patient was inappropriately reassured and incorrectly advised to complete the antibiotic course. Given the frequent use of fluoroquinolones in clinical practice and the potential for severe disability from tendon rupture, we consider it important to remind your readers of this uncommon but potentially devastating adverse drug reaction

Replacing performance status with a simple patient-reported outcome in palliative radiotherapy prognostic modelling

Background and purpose Prognostication is key to determining care in advanced incurable cancer. Although performance status (PS) has been shown to be a strong prognostic predictor, inter-rater reliability is limited, restricting models to specialist settings. This study assessed the extent to which a simple patient-reported outcome measure (PROM), the EQ-5D, may replace PS for prognosis of patients with bone metastases. Materials and methods Data from 1,011 patients in the Dutch Bone Metastasis Study were used. Cox proportional hazards models were developed to investigate the prognostic value of models incorporating PS alone, the EQ-5D SC dimension alone, all EQ-5D dimensions and EQ–VAS, and finally all dimensions and PS. Three prognostic groups were identified and performance assessed using the Harrell’s C-index and Altman-Royston index of separation. Results Replacing performance status (PS) with the self-care (SC) dimension of the EQ-5D provides similar model performance. In our SC-based model, three groups are identified with median survival of 86 days (95 % CI 76–101), 174 days (95 % CI 145–213), and 483 days (95 % CI 431–539). Whilst not statistically significantly different, the C-index was 0.706 for the PS-only model, 0.718 for SC-only and 0.717 in our full model, suggesting patient-report outcome models perform as well as that based on PS. Conclusion Prognostic performance was similar across all models. The SC model provides prognostic value similar to that of PS, particularly where a prognosis of<6 months is considered. Larger, more contemporaneous studies are needed to assess the extent to which PROMs may be of prognostic value, particularly where specialist assessment is less feasible

SY38-2IMPULSIVITY, MOTIVATIONS AND ADDICTION TO ONLINE GAMES

Introduction. Problematic engagement in online video gaming has been considered recently in the appendix of the DSM-5. Underpinning psychological factors are yet to be clarified, mostly in adult populations. We present data from two studies investigating links between motives to play and impulsivity in one hand and excessive gaming in another hand. Methods. Online studies have been conducted on adult gamers in France (n = 516) and Switzerland (n = 1057). Problematic engagement has been assessed in France by DSM-IV-TR adapted substance dependence criteria (DAS) and by IAT in Switzerland. Motivations have been investigated using Yee's model. Impulsivity has been evaluated using respectively BIS-10 and UPPS-P. The French sample has been compared to heroin users and to healthy controls regarding impulsivity. In the Swiss study, cluster analysis has been conducted to identify subgroups of players regarding their engagement in-game, their motivations to play and their impulsivity. Results. DAS has been found to be predicted by BIS high scores as well as by competition and advancement. Problematic gamers presented higher levels of impulsivity than controls but less than heroin dependents. Three of five clusters were identified to be problematic and linked to high levels of impulsivity, achievement and escapism. Conclusion. Achievement motives to play and high impulsivity have been linked to problematic engagement in online videogames in two different samples evaluated by two different methods. Addiction to online gaming showed a difference in impulsivity traits with substance dependence and healthy controls and subgroups of problem gamers has been characterized. These data could help to design tailored treatments for excessive online gamer

P-73AN INVESTIGATION OF ADDICTIONS (SUBSTANCES AND BEHAVIORS) IN A COMMUNITY SAMPLE

Chemical and behavioral addictions are highly prevalent in our societies. Nevertheless, studies investigating a large panel of addictive behaviors in a community sample are lacking from the current literature on the topic. The aim of the current study is to explore addictive behaviors prevalence, characteristics, and interrelations in a sample of French speaking adults from the general population. Both substances (alcohol, tobacco, cannabis, drugs) and behaviors (gambling, Internet, buying, sport, work, mobile phone, eating) were considered. Several features of these addictive behaviors (involved in the triggering of the behaviors) were considered, namely, frequency, loss of control, hedonic aspects, craving, impact upon the daily living, and emotional contexts. 770 subjects answered to the online survey. Descriptive results will be presented for each conducts and their related features (prevalence, comorbidities, specific characteristics associated with each addictive behaviors). Our study thus provides a detailed overview of the current conducts' prevalence along with their co-occurrences. It also sheds some lights on how these behaviors may have an impact upon the daily living, and eventually turn into problematic behaviors. A particular emphasis is set on some behavioral conducts, like Internet gaming which is particularly salien

Advance care planning in the Netherlands

The Dutch health care system fosters a strong public health sector offering accessible generalist care including generalist palliative care. General practitioners are well positioned to conduct ACP, for example, to continue or initiate conversations after hospitalization. However, research shows that ACP conversations are often ad hoc and in frail patients, ACP is often only initiated when admitted to a nursing home by elderly care physicians who are on the staff. Tools that raise awareness of triggers to initiate ACP, screening tools, information brochures, checklists and training have been developed and implemented with funding by national programs which currently focus on implementation projects rather than or in addition to, research. The programs commonly require educational deliverables, patient and public involvement and addressing diversity in patient groups. A major challenge is how to implement ACP systematically and continuously across sectors and disciplines in a way that supports a proactive yet person-centered approach rather than an approach with an exclusive focus on medical procedures. Digital solutions can support continuity of care and communication about care plans. Solutions should fit a culture that prefers trust-based, informal deliberative approaches. This may be supported by involving disciplines other than medicine, such as nursing and spiritual caregiving, and public health approaches. Public Health and primary careGeriatrics in primary car

An Easy-to-Use Prognostic Model for Survival Estimation for Patients with Symptomatic Long Bone Metastases

BACKGROUND: A survival estimation for patients with symptomatic long bone metastases (LBM) is crucial to prevent overtreatment and undertreatment. This study analyzed prognostic factors for overall survival and developed a simple, easy-to-use prognostic model. METHODS: A multicenter retrospective study of 1,520 patients treated for symptomatic LBM between 2000 and 2013 at the radiation therapy and/or orthopaedic departments was performed. Primary tumors were categorized into 3 clinical profiles (favorable, moderate, or unfavorable) according to an existing classification system. Associations between prognostic variables and overall survival were investigated using the Kaplan-Meier method and multivariate Cox regression models. The discriminatory ability of the developed model was assessed with the Harrell C-statistic. The observed and expected survival for each survival category were compared on the basis of an external cohort. RESULTS: Median overall survival was 7.4 months (95% confidence interval [CI], 6.7 to 8.1 months). On the basis of the independent prognostic factors, namely the clinical profile, Karnofsky Performance Score, and presence of visceral and/or brain metastases, 12 prognostic categories were created. The Harrell C-statistic was 0.70. A flowchart was developed to easily stratify patients. Using cutoff points for clinical decision-making, the 12 categories were narrowed down to 4 categories with clinical consequences. Median survival was 21.9 months (95% CI, 18.7 to 25.1 months), 10.5 months (95% CI, 7.9 to 13.1 months), 4.6 months (95% CI, 3.9 to 5.3 months), and 2.2 months (95% CI, 1.8 to 2.6 months) for the 4 categories. CONCLUSIONS: This study presents a model to easily stratify patients with symptomatic LBM according to their expected survival. The simplicity and clarity of the model facilitate and encourage its use in the routine care of patients with LBM, to provide the most appropriate treatment for each individual patient. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence

Early intervention for children at risk of visual processing dysfunctions from 1 year of age: a randomized controlled trial protocol

BACKGROUND: An increasing number of children are suffering from brain damage-related visual processing dysfunctions (VPD). There is currently a lack of evidence-based intervention methods that can be used early in development. We developed a visual intervention protocol suitable from 1 year of age. The protocol is structured, comprehensive and individually adaptive, and is paired with quantitative outcome assessments. Our aim is to investigate the effectiveness of this first visual intervention program for young children with (a risk of) VPD. METHODS: This is a single-blind, placebo-controlled trial that is embedded within standard clinical care. The study population consists of 100 children born very or extremely preterm (< 30 weeks) at 1 year of corrected age (CA), of whom 50% are expected to have VPD. First, children undergo a visual screening at 1 year CA. If they are classified as being at risk of VPD, they are referred to standard care, which involves an ophthalmic and visual function assessment and a (newly developed) visual intervention program. This program consists of a general protocol (standardized and similar for all children) and a supplement protocol (adapted to the specific needs of the child). Children are randomly allocated to an intervention group (starting upon inclusion at 1 year CA) or a control group (postponed: starting at 2 years CA). The control group will receive a placebo treatment. The effectiveness of early visual intervention will be examined with follow-up visual and neurocognitive assessments after 1 year (upon completion of the direct intervention) and after 2 years (upon completion of the postponed intervention). DISCUSSION: Through this randomized controlled trial we will establish the effectiveness of a new and earl

Acute cigarette smoke exposure leads to higher viral infection in human bronchial epithelial cultures by altering interferon, glycolysis and GDF15-related pathways

Background Acute exacerbations of chronic inflammatory lung diseases, such as chronic obstructive pulmonary disease (COPD), are frequently associated with rhinovirus (RV) infections. Despite these associations, the pathogenesis of virus-induced exacerbations is incompletely understood. We aimed to investigate effects of cigarette smoke (CS), a primary risk factor for COPD, on RV infection in airway epithelium and identify novel mechanisms related to these effects. Methods Primary bronchial epithelial cells (PBEC) from COPD patients and controls were differentiated by culture at the air-liquid interface (ALI) and exposed to CS and RV-A16. Bulk RNA sequencing was performed using samples collected at 6 and 24 h post infection (hpi), and viral load, mediator and l-lactate levels were measured at 6, 24 and 48hpi. To further delineate the effect of CS on RV-A16 infection, we performed growth differentiation factor 15 (GDF15) knockdown, l-lactate and interferon pre-treatment in ALI-PBEC. We performed deconvolution analysis to predict changes in the cell composition of ALI-PBEC after the various exposures. Finally, we compared transcriptional responses of ALI-PBEC to those in nasal epithelium after human RV-A16 challenge. Results CS exposure impaired antiviral responses at 6hpi and increased viral replication at 24 and 48hpi in ALI-PBEC. At 24hpi, CS exposure enhanced expression of RV-A16-induced epithelial interferons, inflammation-related genes and CXCL8. CS exposure increased expression of oxidative stress-related genes, of GDF15, and decreased mitochondrial membrane potential. GDF15 knockdown experiments suggested involvement of this pathway in the CS-induced increase in viral replication. Expression of glycolysis-related genes and l-lactate production were increased by CS exposure, and was demonstrated to contribute to higher viral replication. No major differences were demonstrated between COPD and non-COPD-derived cultures. However, cellular deconvolution analysis predicted higher secretory cells in COPD-derived cultures at baseline. Conclusion Altogether, our findings demonstrate that CS exposure leads to higher viral infection in human bronchial epithelium by altering not only interferon responses, but likely also through a switch to glycolysis, and via GDF15related pathways.Pathogenesis and treatment of chronic pulmonary disease

The dynamics in applied COVID-19 pharmacotherapy and the influence of national guidance in The Netherlands: a quantitative and qualitative study

OBJECTIVE: At the beginning of the COVID-19 pandemic in the Netherlands, the Dutch Working Party on Antibiotic Policy constructed an advisory document about off-label drug treatment options that was regularly updated with new scientific findings. The aim of this study is to describe the dynamics in applied COVID-19 pharmacotherapy during the first 100 days of the pandemic and to assess how the national advisory document influenced local hospital policies. METHODS: A multicentre observational cohort study was conducted in six hospitals in the Netherlands. Patients with confirmed COVID-19 admitted between 27 February and 7 June 2020 were studied. Drug prescription data were collected and percentages of patients receiving a specific treatment were calculated. These percentages were plotted together with release dates of the national advisory document. Semi-structured in-depth interviews with hospital pharmacists and infectious diseases specialists were conducted to gain insight into the development and implementation of pharmacotherapy treatment protocols in hospitals. RESULTS: Data from 1511 patients (60% men, mean age 66 years) were analysed. From mid-March (hydroxy)chloroquine was being prescribed in all six hospitals to approximately 70% of patients at admission. Frequencies of other off-label treatments were below 2%. In the week of 6 April 2020, the first hospital discontinued prescribing (hydroxy)chloroquine and the last hospital discontinued in the week of 4 May 2020 (total range -19 to +10 days after the national advisory document advised against its use (1 May 2020)). All interviewees (n=6) stated that the hospitals based their policies mainly on the national advisory document but also assessed scientific literature themselves. Order panels were constructed to support prescribing. CONCLUSION: Dutch hospitals opted en masse for (hydroxy)chloroquine as COVID-19 therapy at the start of the pandemic, although the time until the therapy was no longer prescribed differed by several weeks. The fact that hospitals defined pharmacotherapy regimens based on their own assessment of the scientific literature besides the national advisory document can explain this variation