Investigation of the relationship between fatigue and cognition after stroke

Background: Stroke is among the most common causes of disability and stroke survivors may experience cognitive impairment, low mood and fatigue. These three are often associated, as mood and fatigue share some common symptoms and fatigue can also be expressed in a cognitive manner. Fatigue is multifaceted and cannot be easily defined which complicates its measurement. There is a lack of understanding regarding the relationship between fatigue and cognition after stroke and the studies suffer methodological limitations. Objective: This project examined the above concepts and the relationship between fatigue and cognition, more specifically, speed of information processing, sustained and selective attention. Methods: The relationship was examined by: i) systematically reviewing current evidence on this relationship and ii) by conducting three studies that investigated the relationship between fatigue, mood and cognitive impairment in first stroke survivors in the acute phase without depression, in first stroke survivors in the acute phase with depression and in chronic stroke survivors measuring cognitive aspects of fatigue (Fatigue Scale for Motor and Cognitive Functions) as well. We also iii) explored the reliability of and the components assessed by the Fatigue Severity Scale. Results: The systematic review identified 11 studies that examined the relationship. Results were inconclusive as some studies confirmed a significant relationship while others did not. Overall, the findings suggested that memory, attention and speed of information processing are associated with fatigue after stroke, with coefficients ranging from r= .36 to .46. Levels of fatigue and cognitive impairment were reported as moderate. Our three studies did not reveal any statistically significant association between fatigue (general, cognitive or motor) and cognitive performance (either selective and sustained attention or speed of information processing). We also confirmed the uni-dimensionality of the Fatigue Severity Scale in our sample with the use of component analysis; the scale also revealed nearly excellent internal consistency (α=0.95). Conclusion: The Fatigue Severity Scale is a reliable fatigue scale that is commonly used in stroke research. The Fatigue Scale for Motor and Cognitive Functions is a relatively new fatigue scale with high psychometric properties. The lack of significant relationship between fatigue and cognitive impairment may be attributed to the choice of cognitive components that were examined in this study. Implication of Project/Findings: Cognitive impairment after stroke is very common and so is fatigue. If these two are associated in any way, it will be beneficial to explore such a relationship, or even the lack of it, in order to better understand cognitive mechanisms of fatigue and to potentially incorporate them in future psychological interventions. Further Suggestions: Future studies may benefit from incorporating general and cognitive fatigue scales as well as including domain specific and general cognitive test. The findings of this study highlight the complexity of fatigue and speed of information processing as phenomena. Despite not revealing any significant relationship between certain cognitive aspects and fatigue, it may be worth examining the relationship between fatigue and memory components which are less commonly included in similar studies. Funding: This project was funded by the University of Nottingham (Vice Chancellor’s Scholarship for Research Excellence-European Union; Scholarship Reference Number: RFDX42DB2). No financial or other conflict is declared

Examining the relationship between fatigue and cognition after stroke: a systematic review

Many stroke survivors experience fatigue, which is associated with a variety of factors including cognitive impairment. A few studies have examined the relationship between fatigue and cognition and have obtained conflicting results. The aim of the current study was to review the literature on the relationship between fatigue and cognition post-stroke. The following databases were searched: EMBASE (1980–February, 2014), PsycInfo (1806–February, 2014), CINAHL (1937–February, 2014), MEDLINE (1946–February, 2014), Ethos (1600–February, 2014) and DART (1999–February, 2014). Reference lists of relevant papers were screened and the citation indices of the included papers were searched using Web of Science. Studies were considered if they were on adult stroke patients and assessed the following: fatigue with quantitative measurements (≥ 3 response categories), cognition using objective measurements, and the relationship between fatigue and cognition. Overall, 413 papers were identified, of which 11 were included. Four studies found significant correlations between fatigue and memory, attention, speed of information processing and reading speed (r = −.36 to .46) whereas seven studies did not. Most studies had limitations; quality scores ranged from 9 to 14 on the Critical Appraisal Skills Programme Checklists. There was insufficient evidence to support or refute a relationship between fatigue and cognition post-stroke. More robust studies are needed

Effective chemical management for prevention of aflatoxins in maize

The presence of aflatoxins in maize grain has been an increasing problem in the Mediterranean area, possibly due to climate change such as increased temperatures and extended drought periods. It is therefore important to prevent the growth of aflatoxigenic Aspergillus species in the field. There are no fungicides registered for control A. flavus in maize, so this study investigated the efficacy of azoxystrobin, boscalid, cyprodinil, fludioxonil and cyprodinil + fludioxonil to reduce A. flavus growth, sporulation and aflatoxin production in in vitro, and in maize field studies. Based on in vitro inhibition of mycelial growth, the most effective fungicides were cyprodinil (EC50 0.5 μg mL-1. Further evaluation of the fungicides on maize seeds infected with A. flavus demonstrated that all the fungicides reduced conidium production by 76 to 94%, and reduced aflatoxin contamination. In a 2-year field study, application of cyprodinil + fludioxonil reduced A. flavus ear rot severity by 40%, and was the most effective formulation for reducing aflatoxin contamination, by 83%. The other four single ingredient fungicides also decreased aflatoxin production on maize kernels (fludioxonil by 80%, cyprodinil by 75%, boscalid by 74% and azoxystrobin by 67%). Field data from this study provide farmers with a new effective chemical approach to control A. flavus and aflatoxin production in maize within an integrated strategy for management of aflatoxins in maize

Co-therapy in Open Dialogue: Transforming therapists’ self in a shared space

The present study aimed to explore co-therapists’ relationship and how therapists’ individual presence influences this relationship in Open Dialogue. Although co-therapy is key in Open Dialogue network meetings, the processes of that relationship remain largely understudied. The study applied thematic analysis to semi-structured interviews with 20 Open Dialogue trained therapists working in public and private sectors internationally. The results indicate that therapists are present in a meeting with their experiencing and professional self. Specific co-therapy processes allow co-therapists to attune to one another verbally and physically, creating a shared space that promotes new common understandings, shared responsibility and ultimately a transformation of each therapist’s self and practice. Trust between co-therapists seems to be a prerequisite for co-therapy to flourish. Results of the present study reveal a dynamic influence of co-therapy practice, in which co-therapy promotes a more dialogical personality and allows the therapists’ own transformation, which in turn enables common understandings and sharing of responsibility. Considering the growing interest in dialogical approaches and Open Dialogue trainings, trainers, supervisors, and practitioners need to be aware of and attend to the dynamics of co-therapy relationship in order to care for themselves, their team and ultimately the networks they collaborate with

Effective chemical management for prevention of aflatoxins in maize

The presence of aflatoxins in maize grain has been an increasing problem in the Mediterranean area, possibly due to climate change such as increased temperatures and extended drought periods. It is therefore important to prevent the growth of aflatoxigenic Aspergillus species in the field. There are no fungicides registered for control A. flavus in maize, so this study investigated the efficacy of azoxystrobin, boscalid, cyprodinil, fludioxonil and cyprodinil + fludioxonil to reduce A. flavus growth, sporulation and aflatoxin production in in vitro, and in maize field studies. Based on in vitro inhibition of mycelial growth, the most effective fungicides were cyprodinil (EC50 < 0.05 μg mL-1) and fludioxonil (EC50 <0.11 μg mL-1), while the least effective was boscalid (EC50 4.35-4.50 μg mL-1). Azoxystrobin almost completely inhibited the conidium germination at > 0.5 μg mL-1. Further evaluation of the fungicides on maize seeds infected with A. flavus demonstrated that all the fungicides reduced conidium production by 76 to 94%, and reduced aflatoxin contamination. In a 2-year field study, application of cyprodinil + fludioxonil reduced A. flavus ear rot severity by 40%, and was the most effective formulation for reducing aflatoxin contamination, by 83%. The other four single ingredient fungicides also decreased aflatoxin production on maize kernels (fludioxonil by 80%, cyprodinil by 75%, boscalid by 74% and azoxystrobin by 67%). Field data from this study provide farmers with a new effective chemical approach to control A. flavus and aflatoxin production in maize within an integrated strategy for management of aflatoxins in maize

Disentangling interatomic repulsion and anharmonicity in the viscosity and fragility of glasses

Within the shoving model of the glass transition, the relaxation time and the viscosity are related to the local cage rigidity. This approach can be extended down to the atomic level in terms of the interatomic interaction or potential of mean force. We applied this approach to both real metallic glass formers and model Lennard-Jones glasses. The main outcome of this analysis is that in metallic glasses the thermal expansion contribution is mostly independent of composition and is uncorrelated with the interatomic repulsion: As a consequence, the fragility increases upon increasing the interatomic repulsion steepness. In the Lennard-Jones glasses, the scenario is opposite: Thermal expansion and interatomic repulsion contributions are strongly correlated, and the fragility decreases upon increasing the repulsion steepness. This framework allows one to tell apart systems where “soft atoms make strong glasses” from those where, instead, “soft atoms make fragile glasses.” Hence, it opens up the way for the rational, atomistic tuning of the fragility and viscosity of widely different glass-forming materials all the way from strong to fragile.The support of the EU through VitrimetTech ITN network FP7-PEOPLE-2013-ITN-607080 and DFG FG 1394P1 is thankfully acknowledged

Analysis of volatile emissions from grape berries infected with Aspergillus carbonarius using hyphenated and portable mass spectrometry

Mycotoxins represent a serious risk for human and animal health. Οchratoxin A (OTA) is a carcinogenic mycotoxin produced by A. carbonarius that constitutes a severe problem for viticulture. In this study, we investigate the development of novel detection and on-line monitoring approaches for the detection of OTA in the field (i.e. out of the chemical laboratory) using advanced molecular sensing. Both stand-alone and hyphenated mass spectrometry (MS) based systems (e.g. Time-of-Flight ToF–MS and gas chromatography GC combined with MS) and compact portable membrane inlet MS (MIMS) have been employed for the first time to detect and monitor volatile emissions of grape berries infected by the fungus Aspergillus carbonarius. In vacuo (electron impact—EI) and ambient ionisation (electrospray ionisation—ESI) techniques were also examined. On-line measurements of the volatile emissions of grape berries, infected by various strains of A. carbonarius with different toxicity levels, were performed resulting in different olfactory chemical profiles with a common core of characteristic mass fragments, which could be eventually used for on-site detection and monitoring allowing consequent improvement in food security.ISSN:2045-232

Modeling the Time Evolution of the Nanoparticle-Protein Corona in a Body Fluid

Background: Nanoparticles in contact with biological fluids interact with proteins and other biomolecules, thus forming a dynamic corona whose composition varies over time due to continuous protein association and dissociation events. Eventually equilibrium is reached, at which point the continued exchange will not affect the composition of the corona. Results: We developed a simple and effective dynamic model of the nanoparticle protein corona in a body fluid, namely human plasma. The model predicts the time evolution and equilibrium composition of the corona based on affinities, stoichiometries and rate constants. An application to the interaction of human serum albumin, high density lipoprotein (HDL) and fibrinogen with 70 nm N-iso-propylacrylamide/N-tert-butylacrylamide copolymer nanoparticles is presented, including novel experimental data for HDL. Conclusions: The simple model presented here can easily be modified to mimic the interaction of the nanoparticle protein corona with a novel biological fluid or compartment once new data will be available, thus opening novel applications in nanotoxicity and nanomedicine