Imaging the brain and vascular reactions to headache treatments: a systematic review

BACKGROUND

Neuroimaging studies have made an important contribution to our understanding of headache pathophysiology. This systematic review aims to provide a comprehensive overview and critical appraisal of mechanisms of actions of headache treatments and potential biomarkers of treatment response disclosed by imaging studies.

MAIN BODY

We performed a systematic literature search on PubMed and Embase databases for imaging studies investigating central and vascular effects of pharmacological and non-pharmacological treatments used to abort and prevent headache attacks. Sixty-three studies were included in the final qualitative analysis. Of these, 54 investigated migraine patients, 4 cluster headache patients and 5 patients with medication overuse headache. Most studies used functional magnetic resonance imaging (MRI) (n = 33) or molecular imaging (n = 14). Eleven studies employed structural MRI and a few used arterial spin labeling (n = 3), magnetic resonance spectroscopy (n = 3) or magnetic resonance angiography (n = 2). Different imaging modalities were combined in eight studies. Despite of the variety of imaging approaches and results, some findings were consistent. This systematic review suggests that triptans may cross the blood-brain barrier to some extent, though perhaps not sufficiently to alter the intracranial cerebral blood flow. Acupuncture in migraine, neuromodulation in migraine and cluster headache patients, and medication withdrawal in patients with medication overuse headache could promote headache improvement by reverting headache-affected pain processing brain areas. Yet, there is currently no clear evidence for where each treatment acts, and no firm imaging predictors of efficacy. This is mainly due to a scarcity of studies and heterogeneous treatment schemes, study designs, subjects, and imaging techniques. In addition, most studies used small sample sizes and inadequate statistical approaches, which precludes generalizable conclusions.

CONCLUSION

Several aspects of headache treatments remain to be elucidated using imaging approaches, such as how pharmacological preventive therapies work, whether treatment-related brain changes may influence therapy effectiveness, and imaging biomarkers of clinical response. In the future, well-designed studies with homogeneous study populations, adequate sample sizes and statistical approaches are needed.

Targeting epicardial adipose tissue with exercise, diet, bariatric surgery or pharmaceutical interventions: A systematic review and meta-analysis

Epicardial adipose tissue (EAT) and pericardial adipose tissue (PAT) are metabolically active fat depots implicated in cardiovascular disease, and EAT has potential as a novel cardiac risk factor, suitable as a target for interventions. The objective of this systematic review and meta-analysis was to investigate the evidence whether EAT and PAT volume can be reduced by weight-loss interventions (exercise, diet, bariatric surgery or pharmaceutical interventions). A systematic literature search identified 34 studies that were included in the qualitative synthesis (exercise, n = 10, diet, n = 5, bariatric surgery, n = 9 and pharmaceutical interventions, n = 10). Of the 34 studies, 10 reported sufficient data to be included in the meta-analysis. The meta-analysis was only conducted for changes in EAT volume, since only few controlled studies reported changes in PAT (n = 3) or total cardiac adipose tissue volume (n = 1). A significant pooled effect size (ES) for reduction in EAT volume was observed following weight-loss interventions as compared with control interventions (ES = -0.89, 95% CI: -1.23 to -0.55, P < 0.001). When comparing the effect of exercise training versus control on EAT volume reduction, there was a significant pooled ES favouring exercise training (ES: -1.11, 95% CI: -1.57 to -0.65, P < 0.001). Similarly, the ES of pharmaceutical versus control interventions on EAT volume reduction was significant, favouring pharmaceutical interventions (ES: -0.79, 95% CI: -1.37 to -0.21, P < 0.0072). In conclusion, this systematic review and meta-analysis provides evidence that exercise, diet, bariatric surgery and pharmaceutical interventions can reduce cardiac adipose tissue volume.

Epicardial adipose tissue predicts incident cardiovascular disease and mortality in patients with type 2 diabetes

Background

Cardiac fat is a cardiovascular biomarker but its importance in patients with type 2 diabetes is not clear. The aim was to evaluate the predictive potential of epicardial (EAT), pericardial (PAT) and total cardiac (CAT) fat in type 2 diabetes and elucidate sex differences.

Methods

EAT and PAT were measured by echocardiography in 1030 patients with type 2 diabetes. Follow-up was performed through national registries. The end-point was the composite of incident cardiovascular disease (CVD) and all-cause mortality. Analyses were unadjusted (model 1), adjusted for age and sex (model 2), plus systolic blood pressure, body mass index (BMI), low-density lipoprotein (LDL), smoking, diabetes duration and glycated hemoglobin (HbA_1c) (model 3).

Results

Median follow-up was 4.7 years and 248 patients (191 men vs. 57 women) experienced the composite end-point. Patients with high EAT (> median level) had increased risk of the composite end-point in model 1 [Hazard ratio (HR): 1.46 (1.13; 1.88), p = 0.004], model 2 [HR: 1.31 (1.01; 1.69), p = 0.038], and borderline in model 3 [HR: 1.32 (0.99; 1.77), p = 0.058]. For men, but not women, high EAT was associated with a 41% increased risk of CVD and mortality in model 3 (p = 0.041). Net reclassification index improved when high EAT was added to model 3 (19.6%, p = 0.035). PAT or CAT were not associated with the end-point.

Conclusion

High levels of EAT were associated with the composite of incident CVD and mortality in patients with type 2 diabetes, particularly in men, after adjusting for CVD risk factors. EAT modestly improved risk prediction over CVD risk factors.

Epicardial and pericardial adipose tissues are associated with reduced diastolic and systolic function in type 2 diabetes

The aim of this study was to investigate the association of epicardial (EAT) and pericardial (PAT) adipose tissues with myocardial function in type 2 diabetes (T2D). EAT and PAT were measured by ultrasound in 770 patients with T2D and 234 age- and sex-matched non-diabetic controls. Echocardiography was performed, including tissue Doppler imaging and 2D speckle tracking. Patients with T2D versus controls had increased EAT (4.6 ± 1.8 mm vs. 3.4 ± 1.2 mm, P < 0.0001) and PAT (6.3 ± 2.8 mm vs. 5.3 ± 2.4 mm, P < 0.0001). EAT and PAT were associated with structural cardiac measures both in T2D patients and controls (all P < 0.043), but only in T2D patients with functional measures: PAT was associated with impaired global longitudinal strain [beta coefficient (SE)] [0.11% (0.04), P = 0.002], while EAT was associated with reduced diastolic function by lateral early diastolic myocardial velocity (e'_lat ) [-0.31 (0.05) cm/s, P = 0.001], mitral inflow velocities: peak early (E)/peak atrial (A) ratio [-0.02 (0.01), P = 0.001] and lateral E/e'_lat [0.36 (0.10), P < 0.001]. However, no interaction was found between diabetes status and PAT (P = 0.75) or EAT (P = 0.45). Adipose tissue in intimate relation to the myocardium is higher in patients with T2D versus controls and is associated with functional myocardial measures in T2D.

Insights into the evolutionary conserved regulation of Rio ATPase activity

Eukaryotic ribosome biogenesis is a complex dynamic process which requires the action of numerous ribosome assembly factors. Among them, the eukaryotic Rio protein family members (Rio1, Rio2 and Rio3) belong to an ancient conserved atypical protein kinase/ ATPase family required for the maturation of the small ribosomal subunit (SSU). Recent structure–function analyses suggested an ATPase-dependent role of the Rio proteins to regulate their dynamic association with the nascent pre-SSU. However, the evolutionary origin of this feature and the detailed molecular mechanism that allows controlled activation of the catalytic activity remained to be determined. In this work we provide functional evidence showing a conserved role of the archaeal Rio proteins for the synthesis of the SSU in archaea. Moreover, we unravel a conserved RNA-dependent regulation of the Rio ATPases, which in the case of Rio2 involves, at least, helix 30 of the SSU rRNA and the P-loop lysine within the shared RIO domain. Together, our study suggests a ribosomal RNA-mediated regulatory mechanism enabling the appropriate stimulation of Rio2 catalytic activity and subsequent release of Rio2 from the nascent pre-40S particle. Based on our findings we propose a unified release mechanism for the Rio proteins.

Epicardial, pericardial and total cardiac fat and cardiovascular disease in type 2 diabetic patients with elevated urinary albumin excretion rate

Background We evaluated the association of cardiac adipose tissue including epicardial adipose tissue and pericardial adipose tissue with incident cardiovascular disease and mortality, coronary artery calcium, carotid intima media thickness and inflammatory markers. Design A prospective study of 200 patients with type 2 diabetes and elevated urinary albumin excretion rate (UAER). Methods Cardiac adipose tissue was measured from baseline echocardiography. The composite endpoint comprised incident cardiovascular disease and all-cause mortality. Coronary artery calcium, carotid intima media thickness and inflammatory markers were measured at baseline. Cardiac adipose tissue was investigated as continuous and binary variable. Analyses were performed unadjusted (model 1), and adjusted for age, sex (model 2), body mass index, low-density lipoprotein cholesterol, smoking, glycated haemoglobin, and systolic blood pressure (model 3). Results Patients were followed-up after 6.1 years for non-fatal cardiovascular disease ( n = 29) or mortality ( n = 23). Cardiac adipose tissue ( p = 0.049) and epicardial adipose tissue ( p = 0.029) were associated with cardiovascular disease and mortality in model 1. When split by the median, patients with high cardiac adipose tissue had a higher risk of cardiovascular disease and mortality than patients with low cardiac adipose tissue in unadjusted (hazard ratio 1.9, confidence interval: 1.1; 3.4, p = 0.027) and adjusted (hazard ratio 2.0, confidence interval: 1.1; 3.7, p = 0.017) models. Cardiac adipose tissue ( p =  0.033) was associated with baseline coronary artery calcium (model 1) and interleukin-8 (models 1-3, all p < 0.039). Conclusions In type 2 diabetes patients without coronary artery disease, high cardiac adipose tissue levels were associated with increased risk of incident cardiovascular disease or all-cause mortality even after accounting for traditional cardiovascular disease risk factors. High cardiac adipose tissue amounts were associated with subclinical atherosclerosis (coronary artery calcium) and with the pro-atherogenic inflammatory marker interleukin-8.

The circadian schedule for childhood acute lymphoblastic leukemia maintenance therapy does not influence event-free survival in the NOPHO ALL92 protocol

BACKGROUND

The event-free survival of childhood acute lymphoblastic leukemia (ALL) has been reported to be superior when oral methotrexate (MTX) and 6-mercaptopurine (6MP) maintenance therapy (MT) is administered in the evening compared to the morning.

PROCEDURE

In the ALL92 MT study we prospectively registered the intake of MTX/6MP. The registration was done when blood samples for erythrocyte MTX/6MP metabolite measurements were collected, and referred to the time of intake in the period since last registration. Nine thousand one hundred ninety-five registrations in total. The administration of MTX/6MP was scored as morning, midday, or evening.

RESULTS

Of 532 patients, 296 took their medication consistently in the evening, 129 in the evening 50.0-99.9% of the time, and 101 in the evening <50% of the time, six did not have any registrations. The circadian schedule did not differ significantly by age, sex, MTX/6MP doses, and average absolute neutrophil counts. The circadian schedule groups did differ on risk groups (P = 0.003) with fewer HR patients in the 50-99.9% group, and there was a negative correlation between percentage of time on evening schedule and average WBC (Spearman's rho -0.15; P = 0.0004). Average WBC was not associated with relapse on ALL92. In a Cox multivariate model the circadian schedule of MTX/6MP was not of prognostic significance for the risk of relapse, and the 10-year cumulative relapse risk was below 20% in all groups.

CONCLUSION

An evening schedule may still be recommended based on the previous publications, but in this study morning administration of MTX and 6MP does not seem to impact EFS.

Combining necrosis and platelet markers for perfecting myocardial infarction rule out: how close are we?

Each year, at least 5 million patients in the United States present to hospital emergency departments with the complaint of chest pain, and more than 10% of them will be diagnosed with acute myocardial infarction. One of the foremost tasks of the emergency department physician is to avoid unnecessary admissions and concomitantly to minimize the number of patients discharged home inappropriately. Currently available diagnostic tools, including the electrocardiogram and myocardial markers, have several shortcomings, including low specificity, and delayed sensitivity for the timely detection of myocardial necrosis. Therefore, the search for better methods of rapidly identifying patients with unstable coronary syndromes is one of the utmost priorities of modern emergency medicine. Available biochemical diagnostic tools are discussed in this review, focusing on the potential benefits of combining myocardial necrosis markers with indicators of platelet activation. It is hypothesized that such a combined approach may be more powerful in myocardial infarction risk stratification than separate marker determination.

Neutrophil elastase activity and superoxide production are diminished in neutrophils of alcoholics

Several lines of evidence indicate that neutrophil elastase and oxidants secreted by phagocytic inflammatory cells play key roles in the development of centrilobular emphysema. A recent report suggests that ethanol consumption may have a protective role against this disease in smokers. The aim of this study was to examine the effect of ethanol consumption on neutrophil elastase activity and superoxide production of peripheral blood neutrophils. These activities were measured in neutrophils from 52 male intoxicated patients and compared to activities in neutrophils from 20 male volunteers. Neutrophils from intoxicated patients contained 31% less elastase activity than that found in controls, 0.99 +/- 0.27 versus 1.44 +/- 0.23 micrograms/10(6) neutrophils (p less than 0.0001) and produced 25 to 27% less superoxide than controls in response to phorbol 12-myristate-13-acetate, 0.90 +/- 0.17 versus 1.2 +/- 0.21 nmol/min/10(6) PMN (p less than 0.0001) or N-formylmethionylleucylphenylalanine, 0.64 +/- 0.19 versus 0.88 +/- 0.24 (p less than 0.001). In follow-up studies of 10 patients admitted for acute alcoholism, elastase activity and superoxide production remained low for 2 to 4 days. After 6 to 10 days, elastase activity and superoxide production were significantly greater than they were at Day 0 and approached normal levels. Neutrophils isolated from blood samples of healthy abstaining donors, which had been exposed to ethanol or to plasma from inebriated patients for 16 to 20 h, showed no loss of elastase activity or superoxide production.(ABSTRACT TRUNCATED AT 250 WORDS)