A narrative review on the similarities and dissimilarities between myalgic encephalomyelitis/chronic fatigue syndrome (me/cfs) and sickness behavior

It is of importance whether myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a variant of sickness behavior. The latter is induced by acute infections/injury being principally mediated through proinflammatory cytokines. Sickness is a beneficial behavioral response that serves to enhance recovery, conserves energy and plays a role in the resolution of inflammation. There are behavioral/symptomatic similarities (for example, fatigue, malaise, hyperalgesia) and dissimilarities (gastrointestinal symptoms, anorexia and weight loss) between sickness and ME/CFS. While sickness is an adaptive response induced by proinflammatory cytokines, ME/CFS is a chronic, disabling disorder, where the pathophysiology is related to activation of immunoinflammatory and oxidative pathways and autoimmune responses. While sickness behavior is a state of energy conservation, which plays a role in combating pathogens, ME/CFS is a chronic disease underpinned by a state of energy depletion. While sickness is an acute response to infection/injury, the trigger factors in ME/CFS are less well defined and encompass acute and chronic infections, as well as inflammatory or autoimmune diseases. It is concluded that sickness behavior and ME/CFS are two different conditions

Genetic contributions to self-reported tiredness

Self-reported tiredness and low energy, often called fatigue, are associated with poorer physical and mental health. Twin studies have indicated that this has a heritability between 6 and 50%. In the UK Biobank sample (N=108 976), we carried out a genome-wide association study (GWAS) of responses to the question, ‘Over the last two weeks, how often have you felt tired or had little energy?’ Univariate GCTA-GREML found that the proportion of variance explained by all common single-nucleotide polymorphisms for this tiredness question was 8.4% (s.e.=0.6%). GWAS identified one genome-wide significant hit (Affymetrix id 1:64178756_C_T; P=1.36 × 10−11). Linkage disequilibrium score regression and polygenic profile score analyses were used to test for shared genetic aetiology between tiredness and up to 29 physical and mental health traits from GWAS consortia. Significant genetic correlations were identified between tiredness and body mass index (BMI), C-reactive protein, high-density lipoprotein (HDL) cholesterol, forced expiratory volume, grip strength, HbA1c, longevity, obesity, self-rated health, smoking status, triglycerides, type 2 diabetes, waist–hip ratio, attention deficit hyperactivity disorder, bipolar disorder, major depressive disorder, neuroticism, schizophrenia and verbal-numerical reasoning (absolute rg effect sizes between 0.02 and 0.78). Significant associations were identified between tiredness phenotypic scores and polygenic profile scores for BMI, HDL cholesterol, low-density lipoprotein cholesterol, coronary artery disease, C-reactive protein, HbA1c, height, obesity, smoking status, triglycerides, type 2 diabetes, waist–hip ratio, childhood cognitive ability, neuroticism, bipolar disorder, major depressive disorder and schizophrenia (standardised β’s had absolute values<0.03). These results suggest that tiredness is a partly heritable, heterogeneous and complex phenomenon that is phenotypically and genetically associated with affective, cognitive, personality and physiological processes

Diseño y validación del cuestionario “Actitud hacia la investigación en estudiantes universitarios”

La actitud hacia la investigación es un tema a tomar en cuenta para quienes desean iniciar a los estudiantes universitarios en el mundo de la investigación, ya que los prejuicios y actitudes negativas pueden obstaculizar el aprendizaje. El objetivo de esta investigación fue diseñar y validar un cuestionario para evaluar la actitud hacia la investigación en estudiantes universitarios. A partir de la técnica de redes semánticas, se creó un cuestionario de 28 reactivos, que fue aplicado a 212 estudiantes de Psicología de 3 universidades. Se obtuvo un Alpha de Cronbach de .726 y en el análisis factorial resultaron 2 factores (actitud positiva y negativa) que explicaban el 30.24% de la varianza. Se encontró que los estudiantes de primer año tienden a tener mejor actitud hacia la investigación y esta va disminuyendo conforme avanzan en la carrera. En conclusión, el cuestionario mostró valores psicométricos aceptables para su uso

Illness progression in chronic fatigue syndrome: a shifting immune baseline.

BACKGROUND: Validation of biomarkers for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) across data sets has proven disappointing. As immune signature may be affected by many factors, our objective was to explore the shift in discriminatory cytokines across ME/CFS subjects separated by duration of illness. METHODS: Cytokine expression collected at rest across multiple studies for female ME/CFS subjects (i) 18 years or younger, ill for 2 years or less (n = 18), (ii) 18–50 years of age, ill for 7 years (n = 22), and (iii) age 50 years or older (n = 28), ill for 11 years on average. Control subjects were matched for age and body mass index (BMI). Data describing the levels of 16 cytokines using a chemiluminescent assay was used to support the identification of separate linear classification models for each subgroup. In order to isolate the effects of duration of illness alone, cytokines that changed significantly with age in the healthy control subjects were excluded a priori. RESULTS: Optimal selection of cytokines in each group resulted in subsets of IL-1α, 6, 8, 15 and TNFα. Common to any 2 of 3 groups were IL-1α, 6 and 8. Setting these 3 markers as a triple screen and adjusting their contribution according to illness duration sub-groups produced ME/CFS classification accuracies of 75–88 %. The contribution of IL-1α, higher in recently ill adolescent ME/CFS subjects was progressively less important with duration. While high levels of IL-8 screened positive for ME/CFS in the recently afflicted, the opposite was true for subjects ill for more than 2 years. Similarly, while low levels of IL-6 suggested early ME/CFS, the reverse was true in subjects over 18 years of age ill for more than 2 years. CONCLUSIONS: These preliminary results suggest that IL-1α, 6 and 8 adjusted for illness duration may serve as robust biomarkers, independent of age, in screening for ME/CFS. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12865-016-0142-3) contains supplementary material, which is available to authorized users

Pain characteristics of people with Chronic Fatigue Syndrome

Objectives: Until now, there has been a lack of fundamental research into the pain experienced in chronic fatigue syndrome [CFS]. The aims of this study were to (1) investigate the pain experiences of people with CFS with a range of disability, and (2) identify specific pain characteristics of people with CFS. Methods: Fifty people were recruited, including 10 people who were severely disabled by CFS [25% Group]. Participants completed a structured interview and a series of pain assessments about their current pain, which included the McGill Pain Questionnaire [MPQ], the Pain Anxiety Symptoms Scale [PASS], and visual analog scales. Results: Muscle pain was the most reported painful symptom [68 percent]. The current pain intensity was 43.2 mm ± 20.8 mm measured on a visual analog scale. The MPQ pain rating index was 23.6 ± 10.8. The PASS total score was 37.9 ± 17.6. Thirty percent [N = 15] of participants reported the cervical spine the location of “most severe” pain, followed by the left and right scapular and right lumbar spine [N = 10 each, 20 percent each]. Further analysis indicated that those people, who were severely disabled by CFS, also experienced significantly more pain [P &lt; 0.05]. Conclusion: The results of this study provide objective data to support anecdotal and clinical reports of pain in people with CFS. Pain in people with CFS should be accepted and treated as seriously as other conditions where pain is a significant symptom. Management strategies need to be tailored to the individual requirements of patients presenting with symptoms of both fatigue and pain

Dynamic all-optical drug screening on cardiac voltage-gated ion channels

Abstract Voltage-gated ion channels (VGCs) are prime targets for the pharmaceutical industry, but drug profiling on VGCs is challenging, since drug interactions are confined to specific conformational channel states mediated by changes in transmembrane potential. Here we combined various optogenetic tools to develop dynamic, high-throughput drug profiling assays with defined light-step protocols to interrogate VGC states on a millisecond timescale. We show that such light-induced electrophysiology (LiEp) yields high-quality pharmacological data with exceptional screening windows for drugs acting on the major cardiac VGCs, including hNav1.5, hKv1.5 and hERG. LiEp-based screening remained robust when using a variety of optogenetic actuators (ChR2, ChR2(H134R), CatCh, ChR2-EYFP-βArchT) and different types of organic (RH421, Di-4-ANBDQPQ, BeRST1) or genetic voltage sensors (QuasAr1). The tractability of LiEp allows a versatile and precise alternative to state-of-the-art VGC drug screening platforms such as automated electrophysiology or FLIPR readers