Surface waves and crustal structure on Mars

We detected surface waves from two meteorite impacts on Mars. By measuring group velocity dispersion along the impact-lander path, we obtained a direct constraint on crustal structure away from the InSight lander. The crust north of the equatorial dichotomy had a shear wave velocity of approximately 3.2 kilometers per second in the 5- to 30-kilometer depth range, with little depth variation. This implies a higher crustal density than inferred beneath the lander, suggesting either compositional differences or reduced porosity in the volcanic areas traversed by the surface waves. The lower velocities and the crustal layering observed beneath the landing site down to a 10-kilometer depth are not a global feature. Structural variations revealed by surface waves hold implications for models of the formation and thickness of the martian crust.

Effects of Vitamin D, Omega-3 Fatty Acids and a Home Exercise Program on Prevention of Pre-Frailty in Older Adults: The DO-HEALTH Randomized Clinical Trial

BACKGROUND

The benefits of supplemental vitamin D3, marine omega-3 fatty acids, and a simple home exercise program (SHEP) on frailty prevention in generally healthy community-dwelling older adults are unclear.

OBJECTIVE

To test the effect of vitamin D3, omega-3s, and a SHEP, alone or in combination on incident pre-frailty and frailty in robust older adults over a follow-up of 36 months.

METHODS

DO-HEALTH is a multi-center, double-blind, placebo-controlled, 2x2x2 factorial randomized clinical trial among generally healthy European adults aged 70 years or older, who had no major health events in the 5 years prior to enrollment, sufficient mobility and intact cognitive function. As a secondary outcome of the DO-HEALTH trial, among the subset of participants who were robust at baseline, we tested the individual and combined benefits of supplemental 2,000 IU/day of vitamin D3, 1 g/day of marine omega-3s, and a SHEP on the odds of being pre-frail and frail over 3 years of follow-up.

RESULTS

At baseline, 1,137 out of 2,157 participants were robust (mean age 74.3 years, 56.5% women, mean gait speed 1.18 m/s). Over a median follow-up time of 2.9 years, 696 (61.2%) became pre-frail and 29 (2.6%) frail. Odds ratios for becoming pre-frail were not significantly lower for vitamin D3, or omega 3-s, or SHEP, individually, compared to control (placebo for the supplements and control exercise). However, the three treatments combined showed significantly decreased odds (OR 0.61 [95% CI 0.38-0.98; p=0.04) of becoming pre-frail compared to control. None of the individual treatments or their combination significantly reduced the odds of becoming frail.

CONCLUSION

Robust, generally healthy and active older adults without major comorbidities, may benefit from a combination of high-dose, supplemental vitamin D3, marine omega-3s, and SHEP with regard to the risk of becoming pre-frail over 3 years.

Iron Deficiency and Incident Infections among Community-Dwelling Adults Age 70 Years and Older: Results from the DO-HEALTH Study

OBJECTIVES

To assess if baseline iron deficiency, with or without anemia, is associated with incident infections over 3 years among community-dwelling older adults.

DESIGN

Prospective secondary analysis of DO-HEALTH, a 3-year randomized, double-blind controlled trial.

SETTING AND PARTICIPANTS

2157 community-dwelling adults age 70+ from 5 European countries with good cognitive function and mobility and no major health events in the 5 years prior to enrollment Measurements: Incident infections, their severity and type were recorded every 3 months throughout the 3-year follow-up. Iron deficiency was defined as soluble transferrin receptor (sTfR) levels > 28.1 nmol/l and anemia as hemoglobin levels < 120 g/l for women and 130 g/l for men. We applied negative binomial mixed effects regression models with random effects for countries, and controlling for treatment allocation, age, sex, body mass index, polypharmacy, number of comorbidities, smoking status, living situation, alcohol intake, frailty status, and physical activity levels. A pre-defined stratified analysis was performed to explore if the associations between iron deficiency and infections were consistent by baseline anemia status.

RESULTS

In total, 2141 participants were included in the analyses (mean age 74.9 years, 61.5% of women, 26.8% with iron deficiency). Across all participants, baseline iron deficiency was not associated with incident overall infections, but was associated with a 63% greater rate of incident severe infections requiring hospitalization (incidence rate ratio [IRR] 1.63, 95% Confidence Interval [CI] 1.11-2.41, p=0.01). This association was more pronounced among the 2000 participants who did not have anemia at baseline (IRR=1.80, 95% CI 1.20-2.69, p=0.005).

CONCLUSION

Based on this prospective study among generally healthy European community-dwelling older adults, iron deficiency was not associated with the incidence rate of overall infections but may increase the incidence of severe infections. Intervention studies are needed to prove the causality of this observation.

FRI0384 BODY COMPOSITION AS A MEDIATOR IN THE RELATIONSHIP BETWEEN PHYSICAL ACTIVITY AND PHYSICAL FUNCTION IN LOWER-LIMB OSTEOARTHRITIS: RESULTS FROM THE KHOALA COHORT

Background:

Many trials investigated the beneficial effect of physical activity (PA) on physical function (PF) in people with osteoarthritis (OA), but factors involved in this relationship are poorly understood. Considering the link between OA and obesity and obesity-related disorders, body composition (BC) could be one of these factors.

Objectives:

To examine the relationships between baseline components of PA and 5-year PF scores, considering BC variables measured at 3 years as potential mediators in theses associations (Figure).

Methods:

We used data from the KHOALA cohort, a French population-based multicenter cohort of 878 patients with symptomatic knee and/or hip OA, aged between 40 and 75 years old. Baseline PA intensity (Metabolic Equivalent of Task, MET), frequency (times/week), duration (hours/week) and type (weight-bearing or not) were assessed by the Modifiable Activity Questionnaire. PF was measured with the WOMAC questionnaire at 5 years (higher scores = greater functional limitations).

Skeletal muscle mass (grams) and fat mass (grams) were measured by dual X-ray absorptiometry (DXA) in 358 patients at 3 years. Fat mass index (kg/m2), appendicular fat mass (kg), % of fat mass, lean mass index (kg/m2), appendicular muscle mass (kg), skeletal muscle mass index (kg/m2or %) were calculated based on DXA data. Sarcopenia was defined according to the FNIH Sarcopenia Project recommendations.

A causal mediation analysis was used to highlight the mediating role of BC variables. Bivariate analyses (multiple linear and logistic regressions) were performed to select the variables of interest. Separate generalized linear models were used to describe the relationships between PA components, PF and selected BC variables. Unadjusted and adjusted for baseline confounders (age, gender, number of comorbidities, disease duration, mental health and vitality scores) models were ran.

Results:

A 1-MET increase in baseline PA intensity was significantly associated with an improvement in PF at 5 years (-3 points). Weight-bearing PA was also significantly associated with better PF scores (-5 points).

A 1-MET-increase in PA intensity at baseline was associated with a subsequent decrease at 3 years in fat mass index (-0.86 k/m2), an increase in skeletal muscle mass index (≥ 6%), and a decrease in % of fat mass (-2%). Non-weight-bearing PA was significantly associated with a decrease in fat mass index (-2.5 kg/m2).

A 1-point increase in PF score was associated with a reduction in skeletal muscle mass index (calculated from body mass index, -0.3%) and an increase in skeletal muscle mass index (calculated from height, +3 kg/m2). The presence of sarcopenia was significantly associated with a degradation of PF (+7 points).

Crude analyses indicated that 20.4% of the effect of baseline PA intensity on PF scores at 5 years was mediated by skeletal muscle mass index (calculated from height), 23.2% by fat mass index and 26.6% by % of fat mass. Similarly, 19.3% of the effect of baseline PA type on PF scores at 5 years was mediated by fat mass index and 15.1% by % of fat mass. After adjustment, we found no longer evidence of a mediating role of BC variables in these associations.

Conclusion:

We found significant associations between a 1-MET increase in PA intensity, weight-bearing PA at baseline and improvement in PF at 5 years, without any mediating role of BC variables. Further studies are needed to better understand the factors involved in these associations, especially psychosocial variables.

Disclosure of Interests:

Maud Wieczorek: None declared, Christine Rotonda: None declared, Jérémie SELLAM: None declared, Francis Guillemin Grant/research support from: Francis Guillemin received a grant from Expanscience paid to his institution., Anne-Christine Rat: None declared

SEIS: Insight's Seismic Experiment for Internal Structure of Mars

By the end of 2018, 42 years after the landing of the two Viking seismometers on Mars, InSight will deploy onto Mars' surface the SEIS (Seismic Experiment for Internal Structure) instrument; a six-axes seismometer equipped with both a long-period three-axes Very Broad Band (VBB) instrument and a three-axes short-period (SP) instrument. These six sensors will cover a broad range of the seismic bandwidth, from 0.01 Hz to 50 Hz, with possible extension to longer periods. Data will be transmitted in the form of three continuous VBB components at 2 sample per second (sps), an estimation of the short period energy content from the SP at 1 sps and a continuous compound VBB/SP vertical axis at 10 sps. The continuous streams will be augmented by requested event data with sample rates from 20 to 100 sps. SEIS will improve upon the existing resolution of Viking's Mars seismic monitoring by a factor of ∼ 2500 at 1 Hz and ∼ 200 000 at 0.1 Hz. An additional major improvement is that, contrary to Viking, the seismometers will be deployed via a robotic arm directly onto Mars' surface and will be protected against temperature and wind by highly efficient thermal and wind shielding. Based on existing knowledge of Mars, it is reasonable to infer a moment magnitude detection threshold of M w ∼ 3 at 40 ∘ epicentral distance and a potential to detect several tens of quakes and about five impacts per year. In this paper, we first describe the science goals of the experiment and the rationale used to define its requirements. We then provide a detailed description of the hardware, from the sensors to the deployment system and associated performance, including transfer functions of the seismic sensors and temperature sensors. We conclude by describing the experiment ground segment, including data processing services, outreach and education networks and provide a description of the format to be used for future data distribution.

ELECTRONIC SUPPLEMENTARY MATERIAL

The online version of this article (10.1007/s11214-018-0574-6) contains supplementary material, which is available to authorized users.

Novel approach to two-component speciation analysis. Spectrophotometric flow-based determinations of Fe(II)/Fe(III) and Cr(III)/Cr(VI)

The proposed approach to two-component speciation analysis relies on simultaneous application of two calibration methods to determination of two different forms of an analyte. One form is determined in extrapolative way, whereas the second form is determined in interpolative way, with the use of the same calibration graph, after appropriate chemical treatment, e.g. oxidation or reduction. The applicability of the approach has been verified on the examples of spectrophotometric determinations of Fe(II)/Fe(III) and Cr(VI)/Cr(III) using 1,10-phenanthroline and 1,5-diphenylcarbazide methods, respectively. In the above methods, ascorbic acid and Ce(IV) have been used to reduce Fe(III) to Fe(II) and to oxidize Cr(III) to Cr(VI), respectively. Lab-In-Syringe and SIA systems (for determination of iron and chromium species, respectively) have been applied to make the implementation of the proposed approach more convenient. The approach was verified on the example of determination of the analytes in synthetic and certified reference materials of ground and waste water samples. Using the developed methods, Fe(II)/Fe(III) and Cr(VI)/Cr(III) were determined within the concentration ranges of 0.06-4.0/0.06-3.0 and 0.03-0.5/0.05-7.0mgL^-1, with precision (RSD, %) less than 3.8/2.0 and 2.2/6.0, and accuracy (RE, %) better than 2.9/4.3 and 6.8/5.2, respectively. The detection limits (mgL^-1) are 0.02/0.02 and 0.01/0.02 for determination of both forms of iron and chromium, respectively. The applicability of the approach has been checked by analysis of artesian water (Fe(II)/Fe(III)) and post-production waste samples (Cr(III)/Cr(VI)).

Anisotropic X-Ray Dark-Field Tomography: A Continuous Model and its Discretization

The x-ray dark-field signal measured in grating interferometers is anisotropic, depending on both the beam direction and the grating orientation with respect to the sample. We present a novel general closed-form, continuous forward model of the anisotropic dark-field signal. Furthermore, we derive a discretization using spherical harmonics, leading to a large-scale linear inverse problem. We present first experimental results of a wooden sample, demonstrating marked advantages over previous results, in particular, the resolution of multiple scattering directions in one volume element.

Endogenous event-related potentials in patients with primary Sjögren's syndrome without central nervous system involvement

OBJECTIVES

Endogenous cognitive event-related potentials (CERPs) reflect higher-level processing of sensory information and can be used to evaluate cognitive functions. The aim of this paper was to determine whether there are any abnormalities in the electrophysiological parameters of CERPs in patients with primary Sjögren's syndrome (pSS) but without symptoms of central nervous system (CNS) involvement or mental disorder. The analysis of CERP parameters was then correlated with the clinical status of the patients and with some of the immunological parameters in the patient group.

METHOD

Thirty consecutive patients with pSS (29 females, one male) were included in the study. All the patients underwent CERP examination.

RESULTS

There was a significant prolongation of the latency of P300 and N200 potentials in patients with pSS. Abnormalities in electrophysiological parameters of CERPs correlated with the duration of the disease, salivary gland abnormalities, and elevated erythrocyte sedimentation rate (ESR) values. Patients with coexisting chronic fatigue syndrome (CFS) had larger P300 amplitudes. There were no statistically significant changes in the electrophysiological parameters of CERPs in patients with pSS dependent on the presence of peripheral nervous system (PNS) lesions, skin changes, arthritis, abnormalities in white blood cells and the immune system or the levels of blood lipids.

CONCLUSIONS

The results of the study suggest the presence of a minor cognitive dysfunction in patients with pSS without symptoms of CNS involvement or mental disorder. Cognitive dysfunction correlated with the disease duration time and the severity of inflammatory changes (salivary gland abnormalities and inflammatory markers in the blood). Further and larger longitudinal studies are necessary for confirmation of this correlation.

Genetic analysis of poliovirus strains isolated from sewage in Poland

The study describes genetic characterization of poliovirus (PV) strains isolated from sewage samples in Poland. The analyses were performed for the detection of any putative polio revertants and recombinants in three genomic regions by sequencing analysis. Thirty-six strains were analyzed. The analyzed strains were identified by neutralization assay as 7 strains of serotype P1, 10 strains of serotype P2, and 19 strains of serotype P3. Sewage isolates were sequenced in 5'UTR, VP1, and 3D genomic regions. All detected PVs were classified as vaccine strains on the basis of VP1 sequence. Mutational differences in the VP1 sequences of isolated viruses ranged from 0.0% to 0.4%, indicating a limited replication period. The genetic analysis of the 3D region showed that some strains have recombinant genomes. Nine strains were found as dipartite recombinants (seven strains--S3/S2, one strain--S2/S1, one strain--S3/S1), while one strain was found as tripartite recombinant (S3/S2/S1). No recombinants with non-PV enteroviruses were identified. None of wild-type PVs or vaccine-derived polioviruses (VDPVs) were detected. This study showed the absence of wild or VDPV circulation in the country and demonstrated the usefulness of environmental surveillance in addition to acute flaccid paralysis (AFP) surveillance in support of polio eradication initiatives.

European survey on efficacy and safety of duty-cycled radiofrequency ablation for atrial fibrillation

AIMS

Duty-cycled radiofrequency ablation (RFA) has been used for atrial fibrillation (AF) for around 5 years, but large-scale data are scarce. The purpose of this survey was to report the outcome of the technique.

METHODS AND RESULTS

A survey was conducted among 20 centres from seven European countries including 2748 patients (2128 with paroxysmal and 620 with persistent AF). In paroxysmal AF an overall success rate of 82% [median 80%, interquartile range (IQR) 74-90%], a first procedure success rate of 72% [median 74% (IQR 59-83%)], and a success of antiarrhythmic medication of 59% [median 60% (IQR 39-72%)] was reported. In persistent AF, success rates were significantly lower with 70% [median 74% (IQR 60-92%)]; P = 0.05) as well as the first procedure success rate of 58% [median 55% (IQR 47-81%)]; P = 0.001). The overall success rate was similar among higher and lower volume centres and were not dependent on the duration of experience with duty-cycled RFA (r = -0.08, P = 0.72). Complications were observed in 108 (3.9%) patients, including 31 (1.1%) with symptomatic transient ischaemic attack or stroke, which had the same incidence in paroxysmal and persistent AF (1.1 vs. 1.1%) and was unrelated to the case load (r = 0.24, P = 0.15), bridging anticoagulation to low molecular heparin, routine administration of heparin over the long sheath, whether a transoesophageal echocardiogram was performed in every patient or not and average procedure times.

CONCLUSION

Duty-cycled RFA has a self-reported success and complication rate similar to conventional RFA. After technical modifications a prospective registry with controlled data monitoring should be conducted to assess outcome.

Analysis of the course and treatment of toxocariasis in children-a long-term observation

Toxocariasis is a helminthozoonotic disease caused by ascarid larvae of Toxocara genus: Toxocara canis and Toxocara cati. In the reported study, the clinical course of toxocariasis and administered therapy were evaluated in 103 children. The majority of the children (68.9%) were from the rural environment, with a prevalence of boys (62.1%). At diagnosis of infection, 36 (35%) children reported recurrent abdominal pain, 19 (18.4%) headache, 6 (5.8%) loss of appetite, 2 subfebrile conditions, and 2 arthralgia, Moreover, 23 (22.3%) children demonstrated symptoms of atopic diseases; in 30 (29.1%) children, moderate enlargement of lymphatic nodes was noted. In five children (4.9%), ophthalmic examination revealed unilateral changes in the eye: in two cases retinitis; in one case fibrotic lesions in the vitreous body, complicated 1 year from diagnosis by retinal detachment; and in other children parafoveal lesions and cataract. Only two children with ocular changes at diagnosis reported visual disorders. In 64.3% of children, eosinophilia was observed. A covert form of the disease was diagnosed in 95.1% of the children and an ocular form in 4.9%. In all the children, antiparasitic treatment was implemented, repeated several times in some of them. After therapy, the mean titer of specific antibodies, the number of children with abdominal pains and enlarged lymphatic nodes were decreased, while headaches maintained at unchanged levels. In approximately one fourth of the children with negative results of antibodies after the therapy, the symptoms of the disease were still reported. Evaluation of the efficacy of treatment is not easy due to non-characteristic symptoms and low kinetics of specific anti Toxocara IgG decrease; however, high IgG titers suggest non-effective treatment of concomitant infection requiring subsequent therapy. Due to risk of ocular form, which may develop in any stage of the disease, irrespectively of specific antibodies concentrations, it seems justified to implement antiparasitic treatment in all children infected with T. canis.

Do induced tachycardias within the scope of electrophysiological studies lead to elevated plasma troponin I levels?

AIMS

Troponin I (TNI) is an established marker for the diagnosis of acute coronary syndrome (ACS). The study evaluated if (induced) tachycardiac arrhyhthmias within the scope of the electrophysiological studies (EPS) led to elevation of TNI serum levels.

METHOD

TNI was measured in the serum of 28 patients before and after the EPS. The left ventricular ejection fraction (LV-EF) was investigated by two-dimensional echocardiography. Left ventricle hypertrophy (LVH) was measured according to the recommendations of the American Society of Echocardiography. All patients underwent coronary angiography prior to the EPS, and significant coronary heart disease was defined as stenosis > 50%. The EPS revealed supraventricular and ventricular tachycardias using the 18-step protocol with one, two, and three extrastimuli.

RESULTS

Indications for the EPS were syncope (n = 15), atrioventricular tachycardia (n = 4), non-sustained VT (n = 6), and sustained VT (n = 3). Coronary heart disease (CHD) was detected in 8 patients (1-vessel: n = 3; 2-vessel: n = 4; 3-vessel: n = 1), and 2 patients underwent percutaneous coronary intervention before EPS. Echocardiography revealed normal LV-EF in 18 patients and a reduction in the others (low n = 3, middle n = 5, high n = 2). Thirteen patients suffered from LVH. In 2 patients, external cardioversion was required during the EPS. TNI was elevated over 0.1 ng/ml (risk stratification cut-off for ACS) in 4 patients before and in 12 patients after EPS. There was no relationship between LV-EF, CHD, and the elevation of TNI after the EPS.

CONCLUSION

TNI can be elevated by (induced) tachycardias within the scope of electrophysiological studies without a relationship to LV-EF, LVH, and CHD.

Age related changes in mitochondrial function and new approaches to study redox regulation in mammalian oocytes in response to age or maturation conditions

Mammalian oocytes are long-lived cells in the human body. They initiate meiosis already in the embryonic ovary, arrest meiotically for long periods in dictyate stage, and resume meiosis only after extensive growth and a surge of luteinizing hormone which mediates signaling events that overcome meiotic arrest. Few mitochondria are initially present in the primordial germ cells while there are mitogenesis and structural and functional differentiation and stage-specific formation of functionally diverse domains of mitochondria during oogenesis. Mitochondria are most prominent cell organelles in oocytes and their activities appear essential for normal spindle formation and chromosome segregation, and they are one of the most important maternal contributions to early embryogenesis. Dysfunctional mitochondria are discussed as major factor in predisposition to chromosomal nondisjunction during first and second meiotic division and mitotic errors in embryos, and in reduced quality and developmental potential of aged oocytes and embryos. Several lines of evidence suggest that damage by oxidative stress/reactive oxygen species in dependence of age, altered antioxidative defence and/or altered environment and bi-directional signaling between oocyte and the somatic cells in the follicle contribute to reduced quality of oocytes and blocked or aberrant development of embryos after fertilization. The review provides an overview of mitogenesis during oogenesis and some recent data on oxidative defence systems in mammalian oocytes, and on age-related changes as well as novel approaches to study redox regulation in mitochondria and ooplasm. The latter may provide new insights into age-, environment- and cryopreservation-induced stress and mitochondrial dysfunction in oocytes and embryos.

[EP quiz part 1: Ventricular arrhythmia and tachycardia]

We present the case of a 56-year-old woman without heart disease who perceived a fast heart beat. The Holter ECG showed frequent ventricular premature beats, thus, allowing a tentative diagnosis, which was confirmed electrophysiologically.