Severe early-onset cardiomyopathy and poor prognosis observed in 73 patients with pathogenic KLHL24 variants

Background/Introduction

Pathogenic variants in KLHL24 might cause skin fragility or cardiomyopathy. KLHL24 controls desmin turnover and patients with heterozygous gain-of-function variants (HET-GOF; i.e. overactivity), typically born with epidermolysis bullosa simplex (EBS), can develop dilated cardiomyopathy (DCM), whereas patients with homozygous loss-of-function variants (HOM-LOF) can develop hypertrophic cardiomyopathy (HCM).

Purpose

This study aims to characterize the cardiac phenotype and prognosis of patients with pathogenic KLHL24 variants.

Methods

Observational studies on KLHL24 found in PUBMED were included in this analysis. Patients were stratified according to their genotype and the study outcomes were cardiomyopathy diagnosis and cardiovascular (CV) events. CV events were defined as sudden cardiac death (SCD), death from heart failure (HF) or heart transplantation (HTx). Kaplan-Meier (KM) curves were constructed to visualize the age at diagnosis and CV event free-survival. For the HET-GOF group, this analysis was stratified by sex and log-rank testing was used to test for significant differences in the distribution. To achieve between group balance, the sex-stratified KM curves were weighted for age and cohort.

Results

In total, 73 patients from 14 studies were included in this analysis and Figure 1A shows their geographic distribution. In general, patients have a median age [IQR] of 18 [7–33]), 53% were men, 38% were diagnosed with cardiomyopathy, and 84% were patients with HET-GOF variants. Patients with HOM-LOF variants have a median age of 27 [26–31] and 55% is male (Figure 1B). HOM-LOF variants c.917G>A [p.(Arg306His)] and c.1048G>T [p.(Glu350*)] segregated in 2 Middle Eastern families, reporting 11 patients born from seemingly unaffected consanguineous heterozygous parents. All HOM-LOF patients were diagnosed with HCM before the age of 32 (27, [26–31]; Figure 1C), resulting in 4 CV events (SCD n=3; HTx n=1; Figure 1D). Patients with HET-GOF variants have a median age of 14 [6–33] and 53% were men (Figure 1B). HET-GOF variants c.1A>G, c.1A>T, c.2T>C, c.3G>T, c.3G>A and c.22A>T [p.(Val2_Met29)] segregated with disease in 34 families, reporting 62 patients in 14 countries. All patients with HET-GOF had EBS at birth and 27% was diagnosed with DCM. The probability of diagnosis during lifetime was significantly different (p<0.001, weighted p<0.001) between men (25 [16–34], n=9) and women (45 [31–47], n=8; Figure 1E). In total, 7 CV events (SCD n=1; HF n=4; HTx n=2) were reported for patients with HET-GOF variants. Figure 1F shows the general differences in CV events between sexes (p=0.026, weighted p=0.073). The median age of CV events for men was 20 (n=4) and 54 for women (n=3).

Conclusions

Patients with HOM-LOF variants were diagnosed at an early age with a severe form of HCM. Men with HET-GOF variants were diagnosed with DCM earlier than women. Men also have a higher probability for CV events at a younger age than women.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Research Counsel (ERC-2016-STG)

Exploratory proteome profiling in patients with peripartum cardiomyopathy – a biomarker study on the EORP cohort

Background

The diagnosis of peripartum cardiomyopathy (PPCM) remains challenging as heart failure symptoms may also occur during normal pregnancy. This is further aggravated by the absence of biomarkers specific for diagnosis or prognosis of women with PPCM. Indeed, current evidence from the EURObservational Research Programme (EORP) Registry, an ongoing prospective, international, multicentre, observational registry for women with PPCM, report that the time to diagnosis after symptom onset varies from 19.4 to 38.3 days.

Aims

We performed exploratory serum proteome profiling on patients with PPCM, as compared with healthy postpartum mothers, to uncover novel protein biomarkers that would further our understanding of the pathogenesis of the disease and enhance diagnostic evaluation.

Methods

Demographic and clinical data, as well as serum samples were collected from 84 patients with PPCM from seven EORP participating countries and 29 healthy controls (HC) from South Africa. Serum proteomic profiling was conducted using DIA-based label-free quantitative (LFQ) LC-MS at the time of diagnosis from depleted serum samples. Mass spectrometry data were analyzed by Spectronaut v15 using a study-specific spectral library. Proteomic statistical analysis was performed using Perseus version 2.0.3.0 (FDR=0.05; S=0.1).

Results

Patients with PPCM had advanced heart failure (50% had New York Heart Association functional classes III/IV, mean left ventricular ejection fraction [LVEF] of 33.5%±9.3 [vs 57.0±8.8 in HC, p<0.001]). Amongst the 329 proteins that were identified in the serum samples, 17 proteins were significantly differentially upregulated and 18 downregulated in patients with PPCM as compared to the HC (all p<0.05; Figure 1). Adiponectin (log fold change 1.378, p=0.001), pregnancy-specific beta-1-glycoprotein 1 (1.207, p=0.022), disintegrin metalloproteinase domain-containing protein 12 (1.185, p=0.039), peptidyl-prolyl cis-trans isomerase (1.182, p=0.031) and sulfhydryl oxidase 1 (1.101, p=0.004) were among the upregulated proteins, whilst immunoglobulin kappa variable 2–29 (0.856, p=0.029), ficolin-3 (0.898, p=0.001), platelet basic protein (0.917, p=0.006) and thrombospondin-1 (0.930, p=0.043) were among the downregulated. Gene ontology indicated that thrombospondin receptor activity, fibronectin-binding, and vascular endothelial growth factor receptor 2 binding among the most significant regulated molecular functions. The area under the curve (AUC) of the top 10 up-regulated biomarkers ranged from 0.61–0.68 (p<0.05).

Conclusion

Salient biological themes related to immune response proteins, inflammation, fibrosis, angiogenesis, apoptosis, and blood coagulation were identified to be predominant in PPCM versus HC. This indicates the complex pathophysiological mechanisms of PPCM. The newly identified proteins warrant further studies to evaluate their potential use as diagnostic and prognostic markers for PPCM.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): 1. EurObservational Research Programme in conjunction with the Heart Failure Association of the European Society of Cardiology Study Group on Peripartum Cardiomyopathy2. Cape Heart Institute, University of Cape Town, South Africa

P-452 Suboptimal quality of integrated female oncofertility care is associated with a lowered quality of life and more decisional conflict and regret in female cancer survivors

Study question

Is quality of female oncofertility care associated with quality of life, decisional conflict, regret, reproductive concerns, and fertility preservation knowledge in female cancer survivors?

Summary answer

Receiving high-quality integrated female oncofertility care is associated with an improved quality of life, and with less decisional conflict and regret in female cancer survivors.

What is known already

Female adolescent and young adult cancer patients should be informed about their infertility risks due to cancer treatment. However, adherence to oncofertility guidelines is far from optimal. At this moment, it is not known whether adherence to oncofertility guidelines measured with quality indicators is associated with a better quality of life, less decisional conflict, regret, and reproductive concerns in female cancer survivors

Study design, size, duration

A multicenter cross-sectional survey study was conducted to measure the association between quality of oncofertility care and patient-reported outcome measures (PROMs).

Participants/materials, setting, methods

Female AYA cancer survivors (18-40 years) who were diagnosed in 2016 or 2017, and received a (potential) gonadotoxic treatment were eligible to participate. They were recruited from six hospitals across the Netherlands and were asked to fill in a survey. Quality indicators were used to assess quality of care, and validated scales to assess PROMs. Quality indicator and PROM scores were calculated, and associations were analyzed by T-tests and multilevel multivariate analyses

Main results and the role of chance

In total, 121 out of 344 female cancer survivors participated. Female cancer survivors received a suboptimal quality of care with 8 out of 11 quality indicators scoring <90% adherence. Of all patients, 72,7% was informed about their infertility, 51,2% was offered a referral, with 18,8% all aspects were discussed in counselling, and 35,5% received written and/or digital information. When survivors were informed about infertility risks, and were offered fertility preservation counseling, and received digital/written information (i.e. adherence to three quality indicators), their quality of life was highest, and levels of decisional conflict and regret were lowest. Physical quality of life, decision regret, reproductive concerns, and fertility preservation knowledge scores were significantly influenced by female cancer survivor’s age, relationship status, strength of wish to conceive, and type of cancer.

Limitations, reasons for caution

Selection bias could have occurred as we have no insight into reasons for non-responding and we have a low response rate. Furthermore, recall bias could have played a role as patients were asked to fill in questions three to four years after their diagnosis, treatment, and consultation.

Wider implications of the findings

As quality of oncofertility care is suboptimal, strategies should be developed and tailored to the current gaps, and to guideline-specific barriers, to improve quality of care and, importantly, quality of life in female cancer survivors.

Trial registration number

N/A

A prospective validation of a deep learning-based automated workflow for the interpretation of the echocardiogram

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Us2.ai

Background. Deep learning can automate the interpretation of medical imaging tests. This study aimed to prospectively assess the interchangeability of deep learning algorithms with expert human measurements for interpreting echocardiographic studies, the primary method for assessing cardiac structure and function.

Methods. We compared a deep learning interpretation of 23 echocardiographic parameters—including cardiac volumes, ejection fraction, and Doppler measurements—with three repeated measurements by core lab human experts in a prospective study for submission to the United States Food and Drug Administration (FDA). The primary outcome metric was the individual equivalence coefficient (IEC), which compares the disagreement between deep learning and human readers relative to the disagreement among human readers. The pre-determined non-inferiority criterion was 0.25 for the upper bound of the 95% confidence interval (CI). Secondary outcomes included measures of agreement, including the mean absolute deviation.

Results. We included 602 studies from 600 participants (421 with heart failure, 179 controls, 69% women) with a mean age of 57 ± 16 years. The point estimates of IEC were all <0, indicating that the disagreement between the deep learning and human measures were lower than the disagreement among three core lab readers, and the upper bound of the 95% CI of IECs fell below the prespecified success criterion of 0.25. Secondary endpoints showed good agreement of automated with human expert measurements (Figure), with comparable or lower mean absolute deviations between automated and human experts relative to the mean absolute deviation among human experts.

Conclusion. This prospective validation study demonstrated excellent agreement between deep learning and expert human interpretation for a wide range of echocardiographic measurements. These results highlight the potential of deep learning algorithms to improve efficiency and reduce costs of echocardiography. Abstract Figure.

Global differences in heart failure with preserved ejection fraction: the paragon-hf trial

Background

Heart failure with preserved ejection fraction (HFpEF) is a global public health problem with important regional differences. We investigated these differences in the PARAGON-HF trial, the largest, most inclusive global HFpEF trial.

Methods

We studied differences in clinical characteristics, outcomes and regional treatment effects of Sacubitril/Valsartan in 4796 patients with HFpEF from the PARAGON-HF trial, grouped according to geographic region.

Results

Regional differences in patient characteristics and comorbidities were observed (Figure 1): patients from Western Europe were oldest (75±7 years) with the highest prevalence of atrial fibrillation (36%); Central/Eastern European patients were youngest (71±8 years) with the highest prevalence of coronary artery disease (CAD, 49%); North American patients had the highest prevalence of obesity (64%) with metabolic syndrome; Latin American patients were youngest and had a high prevalence of obesity (53%); Asia-Pacific patients had a high prevalence of diabetes (44%) despite low prevalence of obesity (26%). Rates of the primary composite endpoint of total hospitalizations for HF and death from cardiovascular causes was lowest in patients from Central Europe (9 per 100 patient years) and highest in patients from North America (28 per 100 patient years), which was primarily driven by a greater number of total hospitalizations for HF and independent of confounders. In the total population, sacubitril–valsartan did not result in a significantly lower rate of total hospitalizations for heart failure and death from cardiovascular causes with no significant heterogeneity in treatment response to sacubitril-valsartan across regions.

Conclusion

This first report on regional differences in the largest prospective global trial in HFpEF suggests substantial regional heterogeneity with respect to phenotype, outcomes and quality of life.

Figure 1

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Study funded by Novartis

Ischemic heart disease is more prevalent in low-income-countries and more often undertreated: data from report-hf

Background

The pathogenic role of ischemic heart disease (IHD) in heart failure is well known. However, little is known about the global differences in the prognostic significance and treatment patterns of IHD in acute heart failure (AHF).

Methods

We prospectively enrolled 18,553 patients with AHF from 44 countries and 365 centers in the REPORT-HF registry. Patients with a history of coronary artery disease, an ischemic etiology of the AHF event or coronary revascularization were classified as IHD. Differences in clinical characteristics, treatment and outcome were analyzed.

Results

Compared to 9,344 (50%) patients without IHD, the 9,189 (50%) patients with IHD were older, more often had a left ventricular ejection fraction [LVEF] <40%, (HFrEF) and decompensated chronic HF (DCHF) and had a greater comorbidity burden. Despite patients from lower-income countries having a higher prevalence of IHD (55% vs. 45% in high-income countries), only 27% of patients with IHD from low-income countries were treated with medicines commonly prescribed for HF (Figure A) compared to 16% of patients with IHD from high income countries. After correction for clinical confounders and medication use, patients with IHD had a shorter “door-to-nitrates and -diuretics time” and worse 1-year mortality (hazard ratio: 1.18, 95% CI: 1.09, 1.27, Figure B) irrespective of geographic region (Pinteraction >0.1). We found a significant interaction for prognosis (Pinteraction <0.001) between IHD and HF diagnosis (DCHF vs. new-onset HF) as well as HF subtype (HFrEF vs. HF with preserved ejection fraction) respectively, such that IHD conveyed worse outcomes in patients with new-onset HF and HFrEF respectively in all world regions.

Conclusion

In this large global contemporary cohort of patients with AHF, IHD was more common in patients from low income countries, conveyed worse 1-year mortality, particularly in patients with new onset HF and patients with HFrEF. Despite worse outcomes, patients in regions with the greatest burden of IHD were more often undertreated.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Novartis

Cognitive and brain development is independently influenced by socioeconomic status and polygenic scores for educational attainment

Genetic factors and socioeconomic status (SES) inequalities play a large role in educational attainment, and both have been associated with variations in brain structure and cognition. However, genetics and SES are correlated, and no prior study has assessed their neural associations independently. Here we used a polygenic score for educational attainment (EduYears-PGS), as well as SES, in a longitudinal study of 551 adolescents to tease apart genetic and environmental associations with brain development and cognition. Subjects received a structural MRI scan at ages 14 and 19. At both time points, they performed three working memory (WM) tasks. SES and EduYears-PGS were correlated (r = 0.27) and had both common and independent associations with brain structure and cognition. Specifically, lower SES was related to less total cortical surface area and lower WM. EduYears-PGS was also related to total cortical surface area, but in addition had a regional association with surface area in the right parietal lobe, a region related to nonverbal cognitive functions, including mathematics, spatial cognition, and WM. SES, but not EduYears-PGS, was related to a change in total cortical surface area from age 14 to 19. This study demonstrates a regional association of EduYears-PGS and the independent prediction of SES with cognitive function and brain development. It suggests that the SES inequalities, in particular parental education, are related to global aspects of cortical development, and exert a persistent influence on brain development during adolescence.

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.

Identification of FAM173B as a protein methyltransferase promoting chronic pain

Chronic pain is a debilitating problem, and insights in the neurobiology of chronic pain are needed for the development of novel pain therapies. A genome-wide association study implicated the 5p15.2 region in chronic widespread pain. This region includes the coding region for FAM173B, a functionally uncharacterized protein. We demonstrate here that FAM173B is a mitochondrial lysine methyltransferase that promotes chronic pain. Knockdown and sensory neuron overexpression strategies showed that FAM173B is involved in persistent inflammatory and neuropathic pain via a pathway dependent on its methyltransferase activity. FAM173B methyltransferase activity in sensory neurons hyperpolarized mitochondria and promoted macrophage/microglia activation through a reactive oxygen species–dependent pathway. In summary, we uncover a role for methyltransferase activity of FAM173B in the neurobiology of pain. These results also highlight FAM173B methyltransferase activity as a potential therapeutic target to treat debilitating chronic pain conditions.

Pain is an evolutionarily conserved physiological phenomenon necessary for survival. Yet, pain can become pathological when it occurs independently of noxious stimuli. The molecular mechanisms of pathological pain are still poorly understood, limiting the development of highly needed novel analgesics. Recently, genetic variations in the genomic region encoding FAM173B—a functionally uncharacterized protein—have been linked to chronic pain in humans. In this study, we identify the role and function of FAM173B in the development of pathological pain. We used genetic, biochemical, and behavioral approaches in mice to show that FAM173B is a mitochondrial lysine methyltransferase—a protein that transfers methyl group to donor proteins. By genetically silencing or overexpressing FAM173B in sensory neurons, we showed that FAM173B methyltransferase activity promotes the development of chronic pain. In addition, we discovered that FAM173B methyltransferase activity in the mitochondria of sensory neurons promotes chronic pain via a pathway that depends on the production of reactive oxygen species and on the engagement of spinal cord microglia—engulfing cells of the central nervous system. These data point to an essential role of FAM173B in the regulation of pathological pain.

Normal-mode and free-Air gravity constraints on lateral variations in velocity and density of Earth's mantle

With the use of a large collection of free-oscillation data and additional constraints imposed by the free-air gravity anomaly, lateral variations in shear velocity, compressional velocity, and density within the mantle; dynamic topography on the free surface; and topography on the 660-km discontinuity and the core-mantle boundary were determined. The velocity models are consistent with existing models based on travel-time and waveform inversions. In the lowermost mantle, near the core-mantle boundary, denser than average material is found beneath regions of upwellings centered on the Pacific Ocean and Africa that are characterized by slow shear velocities. These anomalies suggest the existence of compositional heterogeneity near the core-mantle boundary.

On the nearest neighbour interchange distance between evolutionary trees

We present some new results on a well-known distance measure between evolutionary trees. The trees we consider are free 3-trees having n leaves labeled 0,...,n - 1 (representing species), and n - 2 internal nodes of degree 3. The distance between two trees is the minimum number of nearest neighbour interchange (NNI) operations required to transform one into the other. First, we improve an upper bound on the nni-distance between two arbitrary n-node trees from 4n log n (Culik & Wood, 1982, Inf. Pro. Letts. 15, 39-42) to n log n. Second, we present a counterexample disproving several theorems in (Waterman & Smith, 1978, J. theor. Biol. 73, 789-800). Roughly speaking, finding an equal partition between two trees does not imply decomposability of the distance finding problem. Third, we present a polynomial-time approximation algorithm that, given two trees, finds a transformation between them of length O(log n) times their distance. We also present some results of computations we performed on small size trees.

Reduction of ferricytochrome c, methemoglobin and metmyoglobin by hydroxyl and alcohol radicals

We have studied the reaction of ferricytochrome c, methemoglobin and metmyoglobin with OH and alcohol radicals (methanol, ethanol, ethylene glycol and glycerol). These radicals can be divided into three groups: 1. The OH radicals which reduce the ferricytochrome c with a yield of (30 +/- 10)% and methemoglobin with a yield of (40 +/- 10)%. They do not reduce metmyoglobin. The reduction is not a normal bimolecular reaction but is most probably an intramolecular electron transfer of a protein radical. 2. Methanol and ethanol radicals which reduce all three hemoproteins with a yield of (100 +/- 5)%. This reduction is a normal bimolecular reaction. 3. Glycerol radicals which do not reduce the ferrihemoproteins under our experimental conditions. Ethylene glycol radicals do not reduce ferricytochrome c and metmyoglobin but they do reduce methemoglobin with a yield of (30 +/- 10)%.