Genetic interaction between TTG2 and AtPLC1 reveals a role for phosphoinositide signaling in a co-regulated suite of Arabidopsis epidermal pathways

The TTG2 transcription factor of Arabidopsis regulates a set of epidermal traits, including the differentiation of leaf trichomes, flavonoid pigment production in cells of the inner testa (or seed coat) layer and mucilage production in specialized cells of the outer testa layer. Despite the fact that TTG2 has been known for over twenty years as an important regulator of multiple developmental pathways, little has been discovered about the downstream mechanisms by which TTG2 co-regulates these epidermal features. In this study, we present evidence of phosphoinositide lipid signaling as a mechanism for the regulation of TTG2-dependent epidermal pathways. Overexpression of the AtPLC1 gene rescues the trichome and seed coat phenotypes of the ttg2-1 mutant plant. Moreover, in the case of seed coat color rescue, AtPLC1 overexpression restored expression of the TTG2 flavonoid pathway target genes, TT12 and TT13/AHA10. Consistent with these observations, a dominant AtPLC1 T-DNA insertion allele (plc1-1D) promotes trichome development in both wild-type and ttg2-3 plants. Also, AtPLC1 promoter:GUS analysis shows expression in trichomes and this expression appears dependent on TTG2. Taken together, the discovery of a genetic interaction between TTG2 and AtPLC1 suggests a role for phosphoinositide signaling in the regulation of trichome development, flavonoid pigment biosynthesis and the differentiation of mucilage-producing cells of the seed coat. This finding provides new avenues for future research at the intersection of the TTG2-dependent developmental pathways and the numerous molecular and cellular phenomena influenced by phospholipid signaling.

Gut microbiome is associated with recurrence-free survival in patients with resected Stage IIIB-D or Stage IV melanoma treated with immune checkpoint inhibitors

The gut microbiome (GMB) has been associated with outcomes of immune checkpoint blockade therapy in melanoma, but there is limited consensus on the specific taxa involved, particularly across different geographic regions. We analyzed pre-treatment stool samples from 674 melanoma patients participating in a phase-III trial of adjuvant nivolumab plus ipilimumab versus nivolumab, across three continents and five regions. Longitudinal analysis revealed that GMB was largely unchanged following treatment, offering promise for lasting GMB-based interventions. In region-specific and cross-region meta-analyses, we identified pre-treatment taxonomic markers associated with recurrence, including Eubacterium, Ruminococcus, Firmicutes, and Clostridium. Recurrence prediction by these markers was best achieved across regions by matching participants on GMB compositional similarity between the intra-regional discovery and external validation sets. AUCs for prediction ranged from 0.83-0.94 (depending on the initial discovery region) for patients closely matched on GMB composition (e.g., JSD ≤0.11). This evidence indicates that taxonomic markers for prediction of recurrence are generalizable across regions, for individuals of similar GMB composition.

Higher baseline resting metabolic rate is associated with 1-year frailty decline among older adults residing in an urban area

BACKGROUND

Dysregulated energy metabolism is one hypothesized mechanism underlying frailty. Resting energy expenditure, as reflected by resting metabolic rate (RMR), makes up the largest component of total energy expenditure. Prior work relating RMR to frailty has largely been done in cross section with mixed results. We investigated whether and how RMR related to 1-year frailty change while adjusting for body composition.

METHODS

N = 116 urban, predominantly African-American older adults were recruited between 2011 and 2019. One-year frailty phenotype (0-5) was regressed on baseline RMR, frailty phenotype, demographics and body composition (DEXA) in an ordinal logistic regression model. Multimorbidity (Charlson comorbidity scale, polypharmacy) and cognitive function (Montreal Cognitive Assessment) were separately added to the model to assess for change to the RMR-frailty relationship. The model was then stratified by baseline frailty status (non-frail, pre-frail) to explore differential RMR effects across frailty.

RESULTS

Higher baseline RMR was associated with worse 1-year frailty (odds ratio = 1.006 for each kcal/day, p = 0.001) independent of baseline frailty, demographics, and body composition. Lower fat-free mass (odds ratio = 0.88 per kg mass, p = 0.008) was independently associated with worse 1-year frailty scores. Neither multimorbidity nor cognitive function altered these relationships. The associations between worse 1-year frailty and higher baseline RMR (odds ratio = 1.009, p < 0.001) and lower baseline fat-free mass (odds ratio = 0.81, p = 0.006) were strongest among those who were pre-frail at baseline.

DISCUSSION

We are among the first to relate RMR to 1-year change in frailty scores. Those with higher baseline RMR and lower fat-free mass had worse 1-year frailty scores, but these relationships were strongest among adults who were pre-frail at baseline. These relationships were not explained by chronic disease or impaired cognition. These results provide new evidence suggesting higher resting energy expenditure is associated with accelerate frailty decline.

It's about time: small mammal communities and Lyme disease emergence

Theory predicts that biodiversity changes due to climate warming can mediate the rate of disease emergence. The mechanisms linking biodiversity-disease relationships have been described both theoretically and empirically but remain poorly understood. We investigated the relations between host diversity and abundance and Lyme disease risk in southern Quebec, a region where Lyme disease is rapidly emerging. We found that both the abundance of small mammal hosts and the relative abundance of the tick's natural host, the white-footed mouse (Peromyscus leucopus), influenced measures of disease risk in tick vectors (Borrelia burgdorferi infection abundance and prevalence in tick vectors). Our results suggest that the increase in Lyme disease risk is modulated by regional processes involving the abundance and composition of small mammal assemblages. However, the nature and strength of these relationships was dependent both on time and geographic area. The strong effect of P. leucopus abundance on disease risk we report here is of significant concern, as this competent host is predicted to increase in abundance and occurrence in the region, with the northern shift in the range of North American species under climate warming.

Enhanced Critical Field of Superconductivity at an Oxide Interface

The nature of superconductivity and its interplay with strong spin-orbit coupling at the KTaO3(111) interfaces remain a subject of debate. To address this problem, we grew epitaxial LaMnO3/KTaO3(111) heterostructures. We show that superconductivity is robust against the in-plane magnetic field, with the critical field of superconductivity reaching ∼25 T in optimally doped heterostructures. The superconducting order parameter is highly sensitive to the carrier density. We argue that spin-orbit coupling drives the formation of anomalous quasiparticles with vanishing magnetic moment, providing significant condensate immunity against magnetic fields beyond the Pauli paramagnetic limit. These results offer design opportunities for superconductors with extreme resilience against the applied magnetic fields.

NIRVANA-1: maintenance therapy with niraparib versus niraparib-bevacizumab in patients with advanced ovarian cancer

Following the results of the PRIMA and PAOLA-1 trials, the most effective maintenance strategy for International Federation of Gynecology and Obstetrics stage III patients is still debated, raising the question which of those two maintenance strategies is the most effective: PARP inhibitors alone or PARP inhibitors in combination with bevacizumab. The ongoing NIRVANA-1 study will try to answer this question by assessing the efficacy and safety of niraparib + bevacizumab in comparison with niraparib alone after adjuvant chemotherapy for completely resected stage III patients. Stratification factors include tumor BRCA status, International Federation of Gynecology and Obstetrics stage (IIIA vs IIIB/IIIC) and the use of hyperthermic intraperitoneal chemotherapy during surgery - within the OVHIPEC-2 trial. The primary end point will be progression-free survival rate at 24 months. Safety, median progression-free survival and overall survival will also be studied.

Greengenes2 unifies microbial data in a single reference tree

Studies using 16S rRNA and shotgun metagenomics typically yield different results, usually attributed to PCR amplification biases. We introduce Greengenes2, a reference tree that unifies genomic and 16S rRNA databases in a consistent, integrated resource. By inserting sequences into a whole-genome phylogeny, we show that 16S rRNA and shotgun metagenomic data generated from the same samples agree in principal coordinates space, taxonomy and phenotype effect size when analyzed with the same tree.

Diet Quality and the Fecal Microbiota in Adults in the American Gut Project

BACKGROUND

The Dietary Guidelines for Americans advises on dietary intake to meet nutritional needs, promote health, and prevent diseases. Diet affects the intestinal microbiota and is increasingly linked to health. It is vital to investigate the relationships between diet quality and the microbiota to better understand the impact of nutrition on human health.

OBJECTIVES

This study aimed to investigate the differences in fecal microbiota composition in adults from the American Gut Project based on their adherence to the Dietary Guidelines for Americans.

METHODS

This study was a cross-sectional analysis of the 16S sequencing and food frequency data of a subset of adults (n = 432; age = 18-60 y; 65% female, 89% white) participating in the crowdsourced American Gut Project. The Healthy Eating Index-2015 assessed the compliance with Dietary Guideline recommendations. The cohort was divided into tertiles based on Healthy Eating Index-2015 scores, and differences in taxonomic abundances and diversity were compared between high and low scorers.

RESULTS

The mean Total Score for low-scoring adults (58.1 ± 5.4) was comparable with the reported score of the average American adult (56.7). High scorers for the Total Score and components related to vegetables, grains, and dairy had greater alpha diversity than low scorers. High scorers in the fatty acid component had a lower alpha diversity than low scorers (95% CI: 0.35, 1.85). A positive log-fold difference in abundance of plant carbohydrate-metabolizing taxa in the families Lachnospiraceae and Ruminococcaceae was observed in high-scoring tertiles for Total Score, vegetable, fruit, and grain components (Benjamini-Hochberg; q < 0.05).

CONCLUSIONS

Adults with greater compliance to the Dietary Guidelines demonstrated higher diversity in their fecal microbiota and greater abundance of bacteria capable of metabolizing complex carbohydrates, providing evidence on how Dietary Guidelines support the gut microbiota.

Multi-level analysis of the gut-brain axis shows autism spectrum disorder-associated molecular and microbial profiles

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by heterogeneous cognitive, behavioral and communication impairments. Disruption of the gut-brain axis (GBA) has been implicated in ASD although with limited reproducibility across studies. In this study, we developed a Bayesian differential ranking algorithm to identify ASD-associated molecular and taxa profiles across 10 cross-sectional microbiome datasets and 15 other datasets, including dietary patterns, metabolomics, cytokine profiles and human brain gene expression profiles. We found a functional architecture along the GBA that correlates with heterogeneity of ASD phenotypes, and it is characterized by ASD-associated amino acid, carbohydrate and lipid profiles predominantly encoded by microbial species in the genera Prevotella, Bifidobacterium, Desulfovibrio and Bacteroides and correlates with brain gene expression changes, restrictive dietary patterns and pro-inflammatory cytokine profiles. The functional architecture revealed in age-matched and sex-matched cohorts is not present in sibling-matched cohorts. We also show a strong association between temporal changes in microbiome composition and ASD phenotypes. In summary, we propose a framework to leverage multi-omic datasets from well-defined cohorts and investigate how the GBA influences ASD.

Determination of Effect Sizes for Power Analysis for Microbiome Studies Using Large Microbiome Databases

Herein, we present a tool called Evident that can be used for deriving effect sizes for a broad spectrum of metadata variables, such as mode of birth, antibiotics, socioeconomics, etc., to provide power calculations for a new study. Evident can be used to mine existing databases of large microbiome studies (such as the American Gut Project, FINRISK, and TEDDY) to analyze the effect sizes for planning future microbiome studies via power analysis. For each metavariable, the Evident software is flexible to compute effect sizes for many commonly used measures of microbiome analyses, including α diversity, β diversity, and log-ratio analysis. In this work, we describe why effect size and power analysis are necessary for computational microbiome analysis and show how Evident can help researchers perform these procedures. Additionally, we describe how Evident is easy for researchers to use and provide an example of efficient analyses using a dataset of thousands of samples and dozens of metadata categories.

Herbivore-Dependent Induced Volatiles in Pear Plants Cause Differential Attractive Response by Lacewing Larvae

Biological control may benefit from the behavioral manipulation of natural enemies using volatile organic compounds (VOCs). Among these, herbivore-induced plant volatiles (HIPVs) provide potential tools for attracting or retaining predators and parasitoids of insect pests. This work aimed to characterize the VOCs emitted by pear plants in response to attack by Cacopsylla bidens (Hemiptera: Psyllidae), a major pest in pear orchards, to compare these with VOCs induced by a leaf chewing insect, Argyrotaenia sphaleropa (Lepidoptera: Tortricidae), and to evaluate the behavioral response of Chrysoperla externa (Neuroptera: Chrysopidae) to HIPVs from pear plants damaged by either herbivore. The results demonstrated that plants damaged by the pear psylla emitted VOC blends with increased amounts of aliphatic aldehydes. Leafroller damage resulted in increased amounts of benzeneacetonitrile, (E)-4,8-dimethylnona-1,3,7-triene, β-ocimene and caryophyllene. In olfactometer bioassays, larvae of C. externa were attracted to herbivore-damaged plants when contrasted with undamaged plants. When plant odors from psylla-damaged were contrasted with those of leafroller-damaged plants, C.externa preferred the former, also showing shorter response lag-times and higher response rates when psylla-damaged plants were present. Our results suggest that pear plants respond to herbivory by modifying their volatile profile, and that psylla-induced volatiles may be used as prey-specific chemical cues by chrysopid larvae. Our study is the first to report HIPVs in pear plants attacked by C. bidens, as well as the attraction of C. externa to psyllid-induced volatiles.

Insulin-regulated serine and lipid metabolism drive peripheral neuropathy

Diabetes represents a spectrum of disease in which metabolic dysfunction damages multiple organ systems including liver, kidneys and peripheral nerves1,2. Although the onset and progression of these co-morbidities are linked with insulin resistance, hyperglycaemia and dyslipidaemia3-7, aberrant non-essential amino acid (NEAA) metabolism also contributes to the pathogenesis of diabetes8-10. Serine and glycine are closely related NEAAs whose levels are consistently reduced in patients with metabolic syndrome10-14, but the mechanistic drivers and downstream consequences of this metabotype remain unclear. Low systemic serine and glycine are also emerging as a hallmark of macular and peripheral nerve disorders, correlating with impaired visual acuity and peripheral neuropathy15,16. Here we demonstrate that aberrant serine homeostasis drives serine and glycine deficiencies in diabetic mice, which can be diagnosed with a serine tolerance test that quantifies serine uptake and disposal. Mimicking these metabolic alterations in young mice by dietary serine or glycine restriction together with high fat intake markedly accelerates the onset of small fibre neuropathy while reducing adiposity. Normalization of serine by dietary supplementation and mitigation of dyslipidaemia with myriocin both alleviate neuropathy in diabetic mice, linking serine-associated peripheral neuropathy to sphingolipid metabolism. These findings identify systemic serine deficiency and dyslipidaemia as novel risk factors for peripheral neuropathy that may be exploited therapeutically.

Melatonin controls cell proliferation and modulates mitochondrial physiology in pancreatic stellate cells

We have investigated the effects of melatonin on major pathways related with cellular proliferation and energetic metabolism in pancreatic stellate cells. In the presence of melatonin (1 mM, 100 µM, 10 µM, or 1 µM), decreases in the phosphorylation of c-Jun N-terminal kinase and of p44/42 and an increase in the phosphorylation of p38 were observed. Cell viability dropped in the presence of melatonin. A rise in the phosphorylation of AMP-activated protein kinase was detected in the presence of 1 mM and 100 µM melatonin. Treatment with 1 mM melatonin decreased the phosphorylation of protein kinase B, whereas 100 µM and 10 µM melatonin increased its phosphorylation. An increase in the generation of mitochondrial reactive oxygen species and a decrease of mitochondrial membrane potential were noted following melatonin treatment. Basal and maximal respiration, ATP production by oxidative phosphorylation, spare capacity, and proton leak dropped in the presence of melatonin. The expression of complex I of the mitochondrial respiratory chain was augmented in the presence of melatonin. Conversely, in the presence of 1 mM melatonin, decreases in the expression of mitofusins 1 and 2 were detected. The glycolysis and the glycolytic capacity were diminished in cells treated with 1 mM or 100 µM melatonin. Increases in the expression of phosphofructokinase-1 and lactate dehydrogenase were noted in cells incubated with 100 µM, 10 µM, or 1 µM melatonin. The expression of glucose transporter 1 was increased in cells incubated with 10 µM or 1 µM melatonin. Conversely, 1 mM melatonin decreased the expression of all three proteins. Our results suggest that melatonin, at pharmacological concentrations, might modulate mitochondrial physiology and energy metabolism in addition to major pathways involved in pancreatic stellate cell proliferation.

Omega-Test: A Predictive Early-Z Culling to Improve the Graphics Pipeline Energy-Efficiency

The most common task of GPUs is to render images in real time. When rendering a 3D scene, a key step is to determine which parts of every object are visible in the final image. There are different approaches to solve the visibility problem, the Z-Test being the most common. A main factor that significantly penalizes the energy efficiency of a GPU, especially in the mobile arena, is the so-called overdraw, which happens when a portion of an object is shaded and rendered but finally occluded by another object. This useless work results in a waste of energy; however, a conventional Z-Test only avoids a fraction of it. In this article we present a novel microarchitectural technique, the Omega-Test, to drastically reduce the overdraw on a Tile-Based Rendering (TBR) architecture. Graphics applications have a great degree of inter-frame coherence, which makes the output of a frame very similar to the previous one. The proposed approach leverages the frame-to-frame coherence by using the resulting information of the Z-Test for a tile (a buffer containing all the calculated pixel depths for a tile), which is discarded by nowadays GPUs, to predict the visibility of the same tile in the next frame. As a result, the Omega-Test early identifies occluded parts of the scene and avoids the rendering of non-visible surfaces eliminating costly computations and off-chip memory accesses. Our experimental evaluation shows average EDP savings in the overall GPU/Memory system of 26.4 percent and an average speedup of 16.3 percent for the evaluated benchmarks.

Host biology, ecology and the environment influence microbial biomass and diversity in 101 marine fish species

Fish are the most diverse and widely distributed vertebrates, yet little is known about the microbial ecology of fishes nor the biological and environmental factors that influence fish microbiota. To identify factors that explain microbial diversity patterns in a geographical subset of marine fish, we analyzed the microbiota (gill tissue, skin mucus, midgut digesta and hindgut digesta) from 101 species of Southern California marine fishes, spanning 22 orders, 55 families and 83 genera, representing ~25% of local marine fish diversity. We compare alpha, beta and gamma diversity while establishing a method to estimate microbial biomass associated with these host surfaces. We show that body site is the strongest driver of microbial diversity while microbial biomass and diversity is lowest in the gill of larger, pelagic fishes. Patterns of phylosymbiosis are observed across the gill, skin and hindgut. In a quantitative synthesis of vertebrate hindguts (569 species), we also show that mammals have the highest gamma diversity when controlling for host species number while fishes have the highest percent of unique microbial taxa. The composite dataset will be useful to vertebrate microbiota researchers and fish biologists interested in microbial ecology, with applications in aquaculture and fisheries management.

Artificial intelligence-guided, single-lead EKG may be a game-changer for symptom-to-balloon time reduction in ST-elevated myocardial infarction

Background

Over decades, efforts to shave off life-saving minutes from ST-Elevated Myocardial Infarction (STEMI) care centred on reducing door-to-needle and door-to-balloon times. We firmly believe that symptom-to-balloon time should prove a better focus to this end. Challenges come with this goal as it heavily relies on a patient's perception and initiative to seek care, which we deem intelligent and wearable Artificial Intelligence (AI)-driven Single Lead EKG technologies as an attractive solution in modern-day cardiology.

Purpose

To provide an accurate, accessible, and cost-effective AI-driven Single Lead STEMI detection algorithm that can be embedded into wearable devices and employed in a self-administered fashion.

Methods

Database: EKG records from Mexico, Colombia, Argentina, and Brazil from April 2014 to December 2019. Dataset: A total of 11,567 12-lead EKG records of 10[s] length with a sampling frequency of 500 Hz, including the following balanced classes: angiographically confirmed and unconfirmed STEMI, branch blocks, non-specific ST-T abnormalities, normal and abnormal (200+ CPT codes, excluding those mentioned above). Cardiologists manually checked the label of each record to ensure precision. Pre-processing: We discard the first and last 250 samples as they may contain a standardisation pulse. The study applied a digital low pass filter of order 5 with a frequency cut-off of 35 Hz. The mean was subtracted from each Lead. Classification: The determined classes were “STEMI” (Including STEMI in different locations of the myocardium – anterior, inferior, and lateral); and “Not-STEMI” (Combination of randomly sample, branch blocks, non-specific ST-T changes, and abnormal records – 25% of each). Training and Testing: A 1-D Convolutional Neural Network was trained and tested with a dataset proportion of 90/10, respectively. A different model was trained and tested for each Lead, using the central 4,500 samples of the records. The last dense layer outputs a probability for each report of being STEMI or Not-STEMI. Lead V2 showed the best overall results. The model was further tested through the same methodology using the best Lead with a subset of the previous data, excluding the unconfirmed STEMI EKG records (Total 7,230 12-lead EKG records for Confirmed Only STEMI dataset). Performance metrics were reported for each experiment and compared.

Results

Combined STEMI data: Accuracy: 91.2%; Sensitivity: 89.6%; Specificity: 92.9%. Confirmed STEMI Only dataset: Accuracy: 92.4%; Sensitivity: 93.4%; Specificity: 91.4% (Figure 1).

Conclusion

By assiduously improving the quality of the model's input, we continue to assess our algorithm's performance and reliability for future clinical validation as a potential remote monitoring and early STEMI detection device.

Funding Acknowledgement

Type of funding sources: None.

Type III collagen formation is significantly associated with risk of outcome in HFpEF patients but loses its significant association with underlying AF

Introduction

Heart failure with preserved ejection fraction (HFpEF) is the most common type of heart failure, associated with high morbidity and mortality. Atrial fibrillation (AF) has been associated with structural remodelling and fibrosis and can coexist with HFpEF. Type III collagen is the second most abundant collagen in the heart wall and has been associated with cardiac fibrosis. It has been previously shown that type III collagen formation, measured by PRO-C3, is prognostic for all-cause mortality in HFpEF.

Purpose

In this study, we aimed at investigating if the prognostic power of PRO-C3 in relation to all-cause mortality would be affected by underlying AF in HFpEF patients.

Methods

The analysis included 166 individuals with hypertensive HFpEF. The patients were classified in three groups according to NYHA classification, 43.2% in NYHA Class II, 52.5% NYHA Class III and 2.5% NYHA Class IV. A previous history of AF was present in 53.4% of the patients. Cardiac function was assessed by echocardiography and standard clinical measures. Type III collagen formation was evaluated by means of ELISA with the biomarker PRO-C3, which targets the released N-terminal pro-peptide of type III collagen.

Results

Levels of PRO-C3 were significantly elevated in HFpEF patients with AF (p=0.0063). PRO-C3 was significantly predictive of all-cause mortality in HFpEF patients (AUC=0.643, p=0.0053), but lost its significant association when factoring in AF (AUC=0.581, p=0.235). There was an increased risk of all-cause mortality (p=0.0089) but not statistically significant differences in HFpEF patients with AF (p=0.178) with increasing tertiles of PRO-C3.

Conclusions

Type III collagen formation as measured by PRO-C3, was increased in patients with HFpEF and previously diagnosed AF. However, while PRO-C3 can be predictive of all-cause mortality in HFpEF patients, it lacks predicting ability when AF is considered. The presented data suggest a potential role of increased type III collagen formation in HFpEF patients with adverse outcomes, which is consistent with the presence of increased fibrosis, and can potentially be used as a tool of risk stratification.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Nordic Bioscience A/S

Performance metrics of AI-enhanced single lead EKG maintained after entry of organised clustered data

Background

Our experience in creating innovative Artificial Intelligence-guided single lead EKG methodologies for ST-Elevation Myocardial Infarction (STEMI) detection within complex EKG records has been previously validated.

Purpose

By expanding the intricate variables of our previously tested algorithm input, we seek to further improve our STEMI detecting tool.

Methods

11,567 12-lead EKG records (10-s length, 500 Hz sample frequency) derived from the Latin America Telemedicine Infarct Network database from April 2014 to December 2019. From these records, we included the following balanced classes: angiographically confirmed and unconfirmed STEMI (divided by wall affected), branch blocks, non-specific ST-T changes, normal, and abnormal (Remaining 200+ CPT codes). Cardiologist annotations ensured precision (Ground truth). Determined classes were “STEMI” and “Not-STEMI”. A 1-D Convolutional Neural Network model was trained and tested for each lead with dataset proportions of 90/10, respectively. The last dense layer outputs a probability for each record being STEMI/Not-STEMI. The analysis also included performance metrics and false-negative reports.

Results

Overall, the most promising Single lead for STEMI detection was V2 (91.2% Accuracy, 89.6% Sensitivity, and 92.9% Specificity). 55% of false negatives were inferior wall STEMI (Table 1).

Conclusion

Appreciable progress of our new methodology compared to our previous experiences in AI-guided Single Lead for STEMI detection, especially for lead V2. By performing a thorough analysis of false-negative reports, we aspire to identify potential areas of STEMI detection weakness which will become the focus of future ventures.

Funding Acknowledgement

Type of funding sources: None.

No need for a cardiologist for AMI diagnosis – progress of transforming a behemoth telemedicine program with artificial intelligence

Background

The Latin American Telemedicine Infarct Network (LATIN) Telemedicine is a mammoth hub and spoke model that provides an umbrella of AMI protection for 100 million patients. In the program, 826,043 patients had a telemedicine encounter; 7,400 with AMI were diagnosed; 4,332 of them managed with guidelines-based strategies. We have gradually begun implementing a system for using Artificial Intelligence (AI) algorithms embedded into EKGs for rapid and accurate STEMI detection and validated the results with a cardiologist's interpretations.

Purpose

To test whether an AI-driven EKG algorithm can effectively substitute a cardiologist for STEMI telemedicine protocols.

Methods

The AI algorithm construction was in the following fashion. Sample: a selection of 8,511 EKG and 90,592 classified heartbeats. Pre-processing: segmentation of each EKG into individual heartbeats. Training & testing: 90% and 10% of the total dataset, respectively. Classification: 1-D Convolutional Neural Network; the study constructed classes for each heartbeat. The algorithm was next deployed on a consecutive series of LATIN EKG records to diagnose STEMI. We afterwards compared the algorithm's results with eight expert cardiologists' interpretations of the same sample.

Results

This study achieved a concordance of 91% between the AI algorithm and cardiologist interpretation (Figure 1).

Conclusions

The initial results with AI algorithms for STEMI diagnosis are encouraging and may provide the base work for new tools for cardiologists to improve their efficiency. Moreover, implementing this innovative tool may overcome current limitations associated with the telemedical management of this disease.

Funding Acknowledgement

Type of funding sources: None.

Molecular characterization of thioester-containing proteins in Biomphalaria glabrata and their differential gene expression upon Schistosoma mansoni exposure

Schistosomiasis is a disease caused by trematode parasites of the genus Schistosoma that affects approximately 200 million people worldwide. Schistosomiasis has been a persistent problem in endemic areas as there is no vaccine available, currently used anti-helmintic medications do not prevent reinfection, and most concerning, drug resistance has been documented in laboratory and field isolates. Thus, alternative approaches to curtail this human disease are warranted. Understanding the immunobiology of the obligate intermediate host of these parasites, which include the freshwater snail Biomphalaria glabrata, may facilitate the development of novel methods to stop or reduce transmission to humans. Molecules from the thioester-containing protein (TEP) superfamily have been shown to be involved in immunological functions in many animals including corals and humans. In this study we identified, characterized, and compared TEP transcripts and their expression upon S. mansoni exposure in resistant and susceptible strains of B. glabrata snails. Results showed the expression of 11 unique TEPs in B. glabrata snails. These transcripts present high sequence identity at the nucleotide and putative amino acid levels between susceptible and resistant strains. Further analysis revealed differences in several TEPs’ constitutive expression levels between resistant and susceptible snail strains, with C3-1, C3-3, and CD109 having higher constitutive expression levels in the resistant (BS90) strain, whereas C3-2 and TEP-1 showed higher constitutive expression levels in the susceptible (NMRI) strain. Furthermore, TEP-specific response to S. mansoni miracidia exposure reiterated their differential expression, with resistant snails upregulating the expression of both TEP-4 and TEP-3 at 2 h and 48 h post-exposure, respectively. Further understanding the diverse TEP genes and their functions in invertebrate animal vectors will not only expand our knowledge in regard to this ancient family of immune proteins, but also offer the opportunity to identify novel molecular targets that could aid in the efforts to develop control methods to reduce schistosomiasis transmission.

Randomized double-blind controlled trial to assess the efficacy of intravenous acetaminophen associated with strong opioids in the treatment of acute pain in adult cancer patients: study protocol

Background

Cancer pain is one of the most frequent and relevant symptoms in cancer patients and impacts on patient’s quality of life. International and local standards recommend as an initial strategy the use of an analgesic scheme composed of strong opioids associated with adjuvants such as acetaminophen, based upon the assumption that combining drugs could have a better analgesic effect, could allow lowering opioid dosing, and could prevent the occurrence of adverse effects of opioids. However, there is uncertainty about the impact of acetaminophen as an adjuvant in patients who use strong opioids for moderate to severe pain management in cancer patients. The aim of this study is to assess the efficacy and safety of intravenous acetaminophen associated with strong opioids in hospitalized adult cancer patients who have moderate to severe cancer-related pain.

Methods

We will perform a randomized double-blinded controlled study comparing intravenous acetaminophen 1 g 4 times a day versus placebo for 48 h as an adjuvant to strong opioids. We will assess pain intensity as a primary outcome, using the verbal numerical rating scale (VNRS, I0 to 10 scale with higher scores meaning higher pain intensity), and we will compare the mean difference in pain intensity between baseline and 48 h among the placebo and intervention groups. We estimate that a decrease of 1 point in the VNRS would be clinically significant. Assuming a standard deviation in pain intensity of 1.7 points, an alpha of 0.025, and a power of 0.8, we estimate a sample size of 112 patients, with 56 patients in each arm. Secondary outcomes include the difference in total opioid use between baseline and at 48 h among the groups, and adverse effects such as drowsiness, constipation, nausea, and vomiting would be evaluated.

Discussion

The randomized, double-blind, placebo-controlled design is the best strategy to assess the efficacy of acetaminophen as an adjuvant in adult cancer patients with moderate to severe pain who are receiving strong opioids. We expect to contribute to national and international guidelines with these results.

Trial registration

Clinicaltrials.gov NCT04779567. Registered on March 3, 2021. Retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06442-2.

POS0707 POTENTIAL USE OF BELIMUMAB IN LUPUS PATIENTS FROM ARGENTINE COHORT ACCORDING DISEASE ACTIVITY STATE

Background

The goal of targeted treatment in patients with Systemic Lupus Erythematosus (SLE) is to achieve clinical remission or low disease activity, with the best quality of life, low damage rates and better survival 1-4. RELESSAR is a multicenter, cross-sectional study registry of ≥18 years SLE (ACR 97) patients 5.

Objectives

To describe demographic, clinical characteristics and treatments in SLE patients according to disease activity state. To evaluate the proportion of SLE and refractory SLE patients that are potentially candidates for Belimumab treatment (Active SLE despite standard treatment including increased acDNA autoantibodies and low complement).

Methods

We evaluated demographic and clinical data, treatments, score of damage (SLICC), activity (SLEDAI) and comorbidity (Charlson), hospital admissions and severe infections. The patients were compared according to disease activity: remission (SLEDAI = 0 and without corticosteroids), low disease activity (LDA, SLEDAI> 0 and ≤4 and without corticosteroids) and non-optimal control (SLEDAI> 4 and any dose of corticosteroids). Refractory SLE was defined according to Rituximab (RTX) use, non-response to cyclophosphamide or two or more immunosuppressant or splenectomized patients. Potential use of Belimumab according approved prescription in Argentina was analyzed.

Results

Overall, 1277 patients were analyzed: 299 (23.4%) were in remission, 162 (12.7%) in LDA and 816 (63.9%) with non-optimal control of the disease.

Patients in non-optimal control group were younger, less frequently female and they showed less time of disease and lower socioeconomic status (p < 0.001). They were also more prevalent mestizos (p= 0.004), had higher SLEDAI and SLICC indexes (p <0.001) and higher use of immunosuppressant therapy (p <0.001). There was no difference regarding biologic treatment (RTX p= 0.547 and Belimumab p= 0.08). This group had higher proportion of hospital admissions and severe infections (p<0.001, respectively).

Two hundred and one SLE patients fulfilled the use of Belimumab prescription criteria but only 45/201 patients (22,3%) received it in the last visit. Malar rash was the only clinical variable associated with the use of Belimumab (72.7% vs 29.8% p= 0.005).

Seventy-six patients classified as refractory SLE (15.7%) and 56/76 (75.7%) never received Belimumab. Patients on Belimumab therapy were associated to treatment with lower doses of corticoids (p= 0.018) and lower rate of hospital admission caused by SLE flare (p= 0.027).

Conclusion

A high percentage of patients had uncontrolled disease upon entry into the registry and were potential candidates for treatment with Belimumab. The patients who received biologic treatment showed the benefit of requiring fewer doses of corticosteroids and having a lower rate of hospitalizations.

References

[1]Mok CC. Treat-to-target in systemic lupus erythematosus: Are we there yet? Expert Rev Clin Pharmacol. 2016;9(5).

[2]Morand EF, Mosca M. Treat to target, remission and low disease activity in SLE. Vol. 31, Best Practice and Research: Clinical Rheumatology. 2017.

[3]Golder V, Tsang-A-Sjoe MWP. Treatment targets in SLE: Remission and low disease activity state. Rheumatol (United Kingdom). 2020;59.

[4]Ruiz-Irastorza G, Bertsias G. Treating systemic lupus erythematosus in the 21st century: new drugs and new perspectives on old drugs. Vol. 59, Rheumatology (United Kingdom). 2021.

[5]Hochberg MC. Updating the American College of Rheumatology revised criteria for the classification of systemic lupus erythematosus. Arthritis Rheum [Internet]. 1997;40(9):1725. Available from: http://www.ncbi.nlm.nih.gov/pubmed/9324032

Disclosure of Interests

Rosana Quintana: None declared, Lucila Garcia: None declared, Paula Alba: None declared, Susana Roverano: None declared, Analia Alvarez: None declared, Cesar Graf: None declared, Cecilia Pisoni: None declared, Alberto Spindler: None declared, Catalina Gomez: None declared, Heber Matias Figueredo: None declared, Silvia Papasidero: None declared, Raul Horacio Paniego: None declared, Maria DeLaVega: None declared, Emma Estela Civit De Garignani: None declared, Luciana Gonzalez Lucero: None declared, Victoria Martire: None declared, Rodrigo Águila Maldonado: None declared, Sergio Gordon: None declared, Carla Gobbi: None declared, Romina Nieto: None declared, Gretel Rausch: None declared, Vanina Góngora: None declared, Maria Agustina D´Amico: None declared, Diana Dubinsky: None declared, Alberto Omar Orden: None declared, Johana Zacariaz: None declared, Julia Romero: None declared, Mariana Alejandra Pera: None declared, Oscar Rillo: None declared, Roberto Baez: None declared, Valeria Arturi: None declared, Andrea Gonzalez: None declared, Florencia Vivero: None declared, Marcela Schmid: None declared, Victor Caputo: None declared, Maria Silvia Larroude: None declared, Graciela Gomez: None declared, Graciela Rodriguez: None declared, Josefina Marin: None declared, Maria Victoria Collado: None declared, Marisa Jorfen: None declared, Zaida Bedran: None declared, Judith Sarano: None declared, David Zelaya: None declared, MONICA SACNUN: None declared, Pablo Finucci: None declared, Romina Rojas Tessel: None declared, Maria Emilia Sattler: None declared, MAXIMILIANO MACHADO ESCOBAR: None declared, Pablo Astesana: None declared, Ursula Vanesa Paris: None declared, Alberto Allievi: None declared, Juan Manuel Vandale: None declared, Bernardo Pons-Estel: None declared, Guillermo Pons-Estel: None declared, Mercedes García Grant/research support from: GSK grant

POS0438 IDENTIFICATION OF ANTI-CYTOKINE AUTOANTIBODIES WITH POTENTIAL TO PREDICT FLARE IN RHEUMATOID ARTHRITIS PATIENTS UNDERGOING BIOLOGICAL THERAPIES: A DISCOVERY STUDY

Background

The presence of anti-cytokine autoantibodies (ACAAs) seems to be a physiologic mechanism to control the immune response and regulate cytokine activity. Biological therapies also regulate cytokine activities and have greatly improved the quality of life of RA patients. However, alteration of the cytokine network by the use of these treatments may lead to a disbalance in the regulatory system of ACAAs. We hypothesize the ACAAs network may influence the course of immune response in RA patients and may be useful to predict the therapy efficacy.

Objectives

We aimed to explore the potential of circulating ACAAs to predict flare in a cohort of RA patients treated with biological therapy.

Methods

We employed sera at baseline from 194 RA patients of the clinical trial OPTIBIO1 (A Coruña), whose primary endpoint is to evaluate the usefulness of standardized protocol strategies of dose reduction in patients with RA in clinical remission treated with biologics. These patients were treated with TNF inhibitors (Etanercept, N=47; Infliximab, N=12; Adalimumab, N=35; Certolizumab (CTZ), N=17; Golimumab, N=5), Tocilizumab (TCZ, N=60) and Abatacept (ABA, N=18). Patients were in clinical remission (DAS 28 <2.6 or SDAI <5 or ACR/EULAR 2011 criteria) at least from 6 months. Patients were followed during a minimum period of one year and maximum period of 3 years. Flare was considered when remission criteria were not fulfilled. The bead-based antigen array MILLIPLEX MAP Human Cytokine Autoantibody Magnetic Bead Panel was used for the simultaneous detection and quantification in sera of anti-BAFF, anti-G-CSF, anti-IFNβ, anti-IFNγ, anti-IL-1α, anti-IL-6, anti-IL-8, anti-IL-10, anti-IL-12 (p40), anti-IL-15, anti-IL-17A, anti-IL-17F, anti-IL-18, anti-IL-22, and anti-TNFα. Non-parametrical tests, ROC curves and logistic regressions were performed for the statistical data analysis using SPSS. P-value < 0.05 was considered statistically significant.

Results

The levels of anti-17A and anti-IL-1α were increased in the sera from patients who suffered a flare during the follow-up period (N= 76), compared to those who remained in remission (N= 118), showing an area under the curve (AUC) of 0.586 and 0.594, respectively. Segregating by treatment, the levels of anti-17A were specifically increased in those relapsing patients under CTZ (N=6), ABA (N=12) and TCZ (N=20) treatment. The AUC of anti-17A within these three therapies was 0.867, 0.903 and 0.682, respectively. Logistic regression analysis also associated the levels of anti-17A with the risk of suffering a flare in TCZ-treated patients (OR=1.11; p=0.015, for 100 MFI increase). In addition, the TCZ-treated patients who suffered a flare also showed higher levels of anti-IL17F, anti-IL-1α, and anti-IL-18 compared to those that remained in remission, showing AUCs of 0.689, 0.657 and 0.698, respectively. Anti-IL-18 was also associated with the risk of flare in these patients (OR=1.65; p=0.028, for 100 MFI increase). The presence of these three ACAAs was also higher in the TCZ-treated patients who suffered a flare compared to those in remission.

Conclusion

Although further validation of our results is needed, we present a ground-breaking study showing the potential of anti-IL17A, anti-IL-1α, and anti-IL18 to predict flare in RA patients under biological therapies.

References

[1]Bejerano C, et al. Clinical evaluation usefulness of standardized protocol strategies of dose reduction in patients with RA in clinical remission treated with biologic therapies. The Optibio Study. Arthritis Rheumatol. 2016; 68 (suppl 10): 649.

Table 1.

Table showing a summary of the results. CI: confidence interval

• Treatments• ACAAs• AUC (CI 95%; p)Allanti-IL17A0.586 (0.504-0.668; 0.044)anti-IL-1α0.594 (0.512-0.676; 0.028)CTZanti-IL17A0.867 (0.675,1.000; 0.017)ABAanti-IL17A0.903 (0.761-1.000; 0.007)TCZanti-IL-1α0.657 (0.494-0.820; 0.049)anti-IL-17F0.689 (0.551-0.827; 0.018)anti-IL17A0.682 (0.528-0.835; 0.023)anti-IL180.698 (0.545-0.850; 0.013)

Disclosure of Interests

None declared.

Use of verbal de-escalation in reducing need for mechanical restraint in patients with psychotic disorders during non-voluntary transfers from home to the psychiatric emergency department

Introduction

Little is known about the need for mechanical restraint during non-voluntary transfers from patient’s homes to the psychiatric emergency department in patients diagnosed with Paranoid Schizophrenia. Although there is no evidence of its efficacy, one of the main tools used for the reduction of mechanical restraints is verbal de-escalation training.

Objectives

The aim is to describe which symptoms predispose to mechanical restrain in patients with Paranoid Schizophrenia transferred in a non-voluntary manner from home to the psychiatric emergency department, and the effect on reducing mechanical restraints after receiving verbal de-escalation training.

Methods

All patients with Paranoid Schizophrenia who, after being visited by a home psychiatry team, have required non-voluntary transfer from their homes to the psychiatric emergency department were selected (N = 442).

Results

Young age, being male, having a poor adherence to treatment, higher scores for de following variables; Excitement, Grandiosity, Suspiciousness, Hostility, Abstract thinking, Motor tension, Uncooperativeness, Poor attention, Lack of insight and Poor impulse control as well as lower scores in motor retardation on the PANSS, are related to a higher frequency of mechanical restrain (P<0,005). Before the verbal de-escalation training, 43.9% of the transferred patients required mechanical restraint, after the training, the need for restraints was reduced to 25.5% (P<0.001).

Conclusions

Training in verbal de-escalation has allowed an important reduction in mechanical restraints in patients with schizophrenia who have required non-voluntary transfers from home to the psychiatric emergency department.

Disclosure

No significant relationships.

Antithrombotic Treatment after Carotid Stenting in Patients with Concomitant Atrial Fibrillation

BACKGROUND AND PURPOSE

Antithrombotic therapy following carotid artery stent placement with concomitant atrial fibrillation is not well-established. Our aim was to assess the safety and efficacy of the combination of direct oral anticoagulants and a P2Y12 inhibitor at 30 days after carotid artery stent placement in patients with atrial fibrillation.

MATERIALS AND METHODS

We designed an observational single-center study including patients who underwent carotid artery stent placement with concomitant atrial fibrillation. We studied 3 groups according to antithrombotic therapy: 1) the direct oral anticoagulants plus clopidogrel (DC) group: receiving direct oral anticoagulants plus a P2Y12 inhibitor; 2) the triple therapy group: anticoagulation and dual antiplatelet therapy; and 3) the dual antiplatelet therapy group: following dual antiplatelet therapy alone. The safety outcome was a major or clinically relevant non-major bleeding event at the first month. The efficacy outcomes were the thromboembolic events (myocardial infarction, stroke, systemic embolism, or stent thrombosis).

RESULTS

Of 959 patients with carotid artery stent placement, 91 met the inclusion criteria, including 24 patients in the DC group, 42 patients in the triple therapy group, and 25 in the dual antiplatelet therapy group. The mean age was 72.27 (SD, 8.1 ) years, with similar baseline characteristics. The median CHA₂DS₂-VASc score for each group was 6 (interquartile range  = 5-6), 5 (interquartile range = 4-6), and 5 (interquartile range = 4-6), respectively. The median HAS-BLED score was 4 in the 3 groups (P = .17). The primary safety end point was 23.8% in the triple therapy group compared with 4% in the dual antiplatelet therapy group (P = .032), with no bleeding events in the DC group (P = .007). There was 1 stent thrombosis in DC group and a cardioembolic stroke in the dual antiplatelet therapy group (P = .41).

CONCLUSIONS

Among patients with carotid artery stent placement with atrial fibrillation, triple therapy confers a high bleeding risk. A regimen of direct oral anticoagulants plus a P2Y12 inhibitor might confer a good safety profile with significantly lower rates of bleeding and optimal efficacy.

Phylogeny-Aware Analysis of Metagenome Community Ecology Based on Matched Reference Genomes while Bypassing Taxonomy

We introduce the operational genomic unit (OGU) method, a metagenome analysis strategy that directly exploits sequence alignment hits to individual reference genomes as the minimum unit for assessing the diversity of microbial communities and their relevance to environmental factors. This approach is independent of taxonomic classification, granting the possibility of maximal resolution of community composition, and organizes features into an accurate hierarchy using a phylogenomic tree. The outputs are suitable for contemporary analytical protocols for community ecology, differential abundance, and supervised learning while supporting phylogenetic methods, such as UniFrac and phylofactorization, that are seldom applied to shotgun metagenomics despite being prevalent in 16S rRNA gene amplicon studies. As demonstrated in two real-world case studies, the OGU method produces biologically meaningful patterns from microbiome data sets. Such patterns further remain detectable at very low metagenomic sequencing depths. Compared with taxonomic unit-based analyses implemented in currently adopted metagenomics tools, and the analysis of 16S rRNA gene amplicon sequence variants, this method shows superiority in informing biologically relevant insights, including stronger correlation with body environment and host sex on the Human Microbiome Project data set and more accurate prediction of human age by the gut microbiomes of Finnish individuals included in the FINRISK 2002 cohort. We provide Woltka, a bioinformatics tool to implement this method, with full integration with the QIIME 2 package and the Qiita web platform, to facilitate adoption of the OGU method in future metagenomics studies. IMPORTANCE Shotgun metagenomics is a powerful, yet computationally challenging, technique compared to 16S rRNA gene amplicon sequencing for decoding the composition and structure of microbial communities. Current analyses of metagenomic data are primarily based on taxonomic classification, which is limited in feature resolution. To solve these challenges, we introduce operational genomic units (OGUs), which are the individual reference genomes derived from sequence alignment results, without further assigning them taxonomy. The OGU method advances current read-based metagenomics in two dimensions: (i) providing maximal resolution of community composition and (ii) permitting use of phylogeny-aware tools. Our analysis of real-world data sets shows that it is advantageous over currently adopted metagenomic analysis methods and the finest-grained 16S rRNA analysis methods in predicting biological traits. We thus propose the adoption of OGUs as an effective practice in metagenomic studies.

Acceleration of the DNA methylation clock among lynch syndrome-associated mutation carriers

Background

DNA methylation (DNAm) age metrics have been widely accepted as an epigenetic biomarker for biological aging and disease. The purpose of this study is to assess whether or not individuals carrying Lynch Syndrome-associated mutations are affected in their rate of biological aging, as measured by the epigenetic clock.

Methods

Genome-wide bisulfite DNA sequencing data were generated using DNA from CD4 + T-cells obtained from peripheral blood using 27 patient samples from Lynch syndrome families. Horvath’s DNAm age model based on penalized linear regression was applied to estimate DNAm age from patient samples with distinct clinical and genetic characteristics to investigate cancer mutation-related aging effects.

Results

Both Lynch mutation carriers and controls exhibited high variability in their estimated DNAm age, but regression analysis showed steeper slope for the Lynch mutation carriers. Remarkably, six Lynch Syndrome-associated mutation carriers showed a strong correlation to the control group, and two sisters carrying Lynch Syndrome-associated mutations, with no significant difference in lifestyle and similar chronological age, were assigned very different DNAm age.

Conclusions

Future studies will be required to explore, in larger patient populations, whether specific epigenetic age acceleration is predictive of time-to-cancer development, treatment response, and survival. Epigenetic clock DNAm metrics may be affected by the presence of cancer mutations in the germline, and thus show promise of potential clinical utility for stratified surveillance strategies based on the relative risk for imminent emergence of tumor lesions in otherwise healthy Lynch Syndrome-associated mutation carriers.

Applications and Comparison of Dimensionality Reduction Methods for Microbiome Data

Dimensionality reduction techniques are a key component of most microbiome studies, providing both the ability to tractably visualize complex microbiome datasets and the starting point for additional, more formal, statistical analyses. In this review, we discuss the motivation for applying dimensionality reduction techniques, the special characteristics of microbiome data such as sparsity and compositionality that make this difficult, the different categories of strategies that are available for dimensionality reduction, and examples from the literature of how they have been successfully applied (together with pitfalls to avoid). We conclude by describing the need for further development in the field, in particular combining the power of phylogenetic analysis with the ability to handle sparsity, compositionality, and non-normality, as well as discussing current techniques that should be applied more widely in future analyses.

Molnupiravir for Oral Treatment of Covid-19 in Nonhospitalized Patients

BACKGROUND

New treatments are needed to reduce the risk of progression of coronavirus disease 2019 (Covid-19). Molnupiravir is an oral, small-molecule antiviral prodrug that is active against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

METHODS

We conducted a phase 3, double-blind, randomized, placebo-controlled trial to evaluate the efficacy and safety of treatment with molnupiravir started within 5 days after the onset of signs or symptoms in nonhospitalized, unvaccinated adults with mild-to-moderate, laboratory-confirmed Covid-19 and at least one risk factor for severe Covid-19 illness. Participants in the trial were randomly assigned to receive 800 mg of molnupiravir or placebo twice daily for 5 days. The primary efficacy end point was the incidence hospitalization or death at day 29; the incidence of adverse events was the primary safety end point. A planned interim analysis was performed when 50% of 1550 participants (target enrollment) had been followed through day 29.

RESULTS

A total of 1433 participants underwent randomization; 716 were assigned to receive molnupiravir and 717 to receive placebo. With the exception of an imbalance in sex, baseline characteristics were similar in the two groups. The superiority of molnupiravir was demonstrated at the interim analysis; the risk of hospitalization for any cause or death through day 29 was lower with molnupiravir (28 of 385 participants [7.3%]) than with placebo (53 of 377 [14.1%]) (difference, -6.8 percentage points; 95% confidence interval [CI], -11.3 to -2.4; P = 0.001). In the analysis of all participants who had undergone randomization, the percentage of participants who were hospitalized or died through day 29 was lower in the molnupiravir group than in the placebo group (6.8% [48 of 709] vs. 9.7% [68 of 699]; difference, -3.0 percentage points; 95% CI, -5.9 to -0.1). Results of subgroup analyses were largely consistent with these overall results; in some subgroups, such as patients with evidence of previous SARS-CoV-2 infection, those with low baseline viral load, and those with diabetes, the point estimate for the difference favored placebo. One death was reported in the molnupiravir group and 9 were reported in the placebo group through day 29. Adverse events were reported in 216 of 710 participants (30.4%) in the molnupiravir group and 231 of 701 (33.0%) in the placebo group.

CONCLUSIONS

Early treatment with molnupiravir reduced the risk of hospitalization or death in at-risk, unvaccinated adults with Covid-19. (Funded by Merck Sharp and Dohme; MOVe-OUT ClinicalTrials.gov number, NCT04575597.).

Phase 2/3 Trial of Molnupiravir for Treatment of Covid-19 in Nonhospitalized Adults

Molnupiravir in Nonhospitalized Patients Molnupiravir induces viral mutations to a threshold beyond which Covid-19 cannot replicate. For nonhospitalized adults with mild-to-moderate Covid-19 symptoms before randomization, molnupiravir did not have dose-related effects on adverse events or laboratory results; 3.1% of patients were hospitalized or died compared with 5.4% treated with placebo.

Stool multi-omics for the study of host-microbe interactions in inflammatory bowel disease

Inflammatory Bowel Disease (IBD) is a chronic immune-mediated inflammatory disease of the gastrointestinal tract that is a growing public burden. Gut microbes and their interactions with hosts play a crucial role in disease pathogenesis and progression. These interactions are complex, spanning multiple physiological systems and data types, making comprehensive disease assessment difficult, and often overwhelming single-omic capabilities. Stool-based multi-omics is a promising approach for characterizing host-gut microbiome interactions using deep integration of technologies such as 16S rRNA sequencing, shotgun metagenomics, meta-transcriptomics, metabolomics, and metaproteomics. The wealth of information generated through multi-omic studies is poised to usher in advancements in IBD research and precision medicine. This review highlights historical and recent findings from stool-based muti-omic studies that have contributed to unraveling IBD's complexity. Finally, we discuss common pitfalls, issues, and limitations, and how future pipelines should address them to standardize multi-omics in IBD research and beyond.

Efficient computation of Faith's phylogenetic diversity with applications in characterizing microbiomes

The number of publicly available microbiome samples is continually growing. As data set size increases, bottlenecks arise in standard analytical pipelines. Faith's phylogenetic diversity (Faith's PD) is a highly utilized phylogenetic alpha diversity metric that has thus far failed to effectively scale to trees with millions of vertices. Stacked Faith's phylogenetic diversity (SFPhD) enables calculation of this widely adopted diversity metric at a much larger scale by implementing a computationally efficient algorithm. The algorithm reduces the amount of computational resources required, resulting in more accessible software with a reduced carbon footprint, as compared to previous approaches. The new algorithm produces identical results to the previous method. We further demonstrate that the phylogenetic aspect of Faith's PD provides increased power in detecting diversity differences between younger and older populations in the FINRISK study's metagenomic data.

Uniform Manifold Approximation and Projection (UMAP) Reveals Composite Patterns and Resolves Visualization Artifacts in Microbiome Data

Microbiome data are sparse and high dimensional, so effective visualization of these data requires dimensionality reduction. To date, the most commonly used method for dimensionality reduction in the microbiome is calculation of between-sample microbial differences (beta diversity), followed by principal-coordinate analysis (PCoA). Uniform Manifold Approximation and Projection (UMAP) is an alternative method that can reduce the dimensionality of beta diversity distance matrices. Here, we demonstrate the benefits and limitations of using UMAP for dimensionality reduction on microbiome data. Using real data, we demonstrate that UMAP can improve the representation of clusters, especially when the clusters are composed of multiple subgroups. Additionally, we show that UMAP provides improved correlation of biological variation along a gradient with a reduced number of coordinates of the resulting embedding. Finally, we provide parameter recommendations that emphasize the preservation of global geometry. We therefore conclude that UMAP should be routinely used as a complementary visualization method for microbiome beta diversity studies. IMPORTANCE UMAP provides an additional method to visualize microbiome data. The method is extensible to any beta diversity metric used with PCoA, and our results demonstrate that UMAP can indeed improve visualization quality and correspondence with biological and technical variables of interest. The software to perform this analysis is available under an open-source license and can be obtained at https://github.com/knightlab-analyses/umap-microbiome-benchmarking; additionally, we have provided a QIIME 2 plugin for UMAP at https://github.com/biocore/q2-umap.

Association of soluble ST2 and right ventricular dysfunction with mortality in chronic hemodialysis patients

Background

End stage kidney disease (ESKD), is a triggering and facilitating factor for cardiac remodelling (i.e., morphologic hypertrophy and/or dilatation associated with deterioration of systolic and/or diastolic function) that contribute to heart failure (HF). RV dysfunction (RVD) has been demonstrated to predict mortality in ESKD patients.

Purpose

The present study aimed to investigate the potential associations between RVD and circulating biomarkers of myocardial inflammation and fibrosis with all-cause mortality in HD patients.

Method

We performed a retrospective single-centre cohort study of prevalent patients admitted in a chronic HD program for more than 3 months. Clinical characteristics and echocardiographic parameters were assessed in all patients. Pre-dialysis blood samples for measurement of inflammatory (e.g., C reactive protein, interleukin-1, interleukin-18) and fibrotic (e.g., soluble suppression of tumorigenesis-2 [sST2], galectin-3, C-terminal pro-peptide of procollagen type I and N-terminal pro-peptide of procollagen type III) biomarkers were collected. RVD was defined using tricuspid annular plane systolic excursion (TAPSE) &lt;1.7 cm or pulsed Doppler peak annular velocity (S') &lt;9.5 cm/s. The ability of sST2 to discriminate between mortality was assessed using AuROC curve.

Results

We enrolled forty-eight patients, mean patients age was 74 (64 – 79)years, and 62.5% were males. 95.8% of the patients had high blood pressure, and at least 70.8% had HF criteria. About 52.1% of the patients were on OnLine HDF. Regarding the echocardiogram parameters, 56.3% had no functional heart disease, 10.4% had LVD (LVEF ≤45% and diastolic dysfunction ≥ grade 2), and 33.3% had RVD (TAPSE &lt;17mm and/or S'&lt;9.5cm/s), with or without LVD. Mortality was higher 45.5% (log-rank, p=0.003) in patients with RVD as diagnosed by S' than in patients without RVD. No difference in mortality was observed for RVD defined by TAPSE. There were no differences in the morphology and function parameters of the left ventricle between patients with and without RVD. From all biomarkers measured only sST2 was associated with RVD. Indeed, an age- and sex-adjusted analyses showed that doubling of sST2 was inversely associated with a decreased in S' (estimate = −2.03, 95% CI [−3.04 to −1.00] cm/s; P=0.002). Mortality was increased in patients with sST2 ≥40.45 ng/mL compared to patients with sST2 &lt;40.45 ng/mL (66.7% vs. 18.9%, log-rank; p=0.004).

Conclusion

This preliminary data would suggest that patients on chronic HD, circulating levels of sST2 were independently associated with RVD. In addition, elevated sST2 levels and RVD were associated with increased all-cause mortality. The myocardial pro-remodelling effect of sST2 in HD patients with RVD warrants further investigation.

Funding Acknowledgement

Type of funding sources: None.

Impact of previous cardiac conditions in prognosis and clinical management of patient with COVID-19 infection

Background

Recent studies suggest a higher mortality rate because of COVID-19 in patients with previous cardiac conditions compared to those without. Given the limited resources of intensive care units (ICU) during the pandemic outbreak, this fact has important implications.

Purpose

The main purpose of this study was to compare the 30-day mortality of the COVID-19 infection in patients with and without previous cardiac conditions. The secondary end point was to assess the differences in clinical severity of the infection (as development of Acute Respiratory Distress Syndrome – ARDS) and ICU admission amongst these patients.

Methods

A total of 1708 consecutive patients were prospectively included. The inclusion criteria were: a confirmed positive diagnosis of COVID-19 infection by PCR and being admitted to our centre between 18th and 23rd March 2020 and 22nd August and 9th January 2021. Patients were classified in two groups according to the presence of previous cardiac conditions (defined as previous history of myocardial infarction, heart failure and atrial fibrillation). Other comorbidities were extensively explored and Charlson Comorbidity Index was calculated. A propensity-score matching was performed and 145 patients with previous cardiac conditions were matched with 145 patients without.

Results

The group of patients with a previous cardiac condition included 421 patients (24.6%). The crude analysis showed a higher 30-day mortality rate among patients with previous cardiac affections (35.6% vs. 14.6%, p&lt;0.001). They were also less likely to be admitted to the ICU (9.8% vs. 6.2%, p=0.022) and had a higher prevalence ARDS (48.9% vs. 33.9%, p&lt;0.001). In the matched cohort, there were no significant differences between both groups regarding mortality (24.8% in the group of patients with previous cardiac conditions vs. 31.0%, p=0.272) nor ARDS prevalence (50.3% vs. 53.1%, p=0.655). There was a trend toward patients with previous cardiac conditions to be less likely to be admitted to the ICU (4.8% vs. 9.7%, p=0.090).

Conclusions

Patients with a personal history of previous cardiac conditions were less likely to be admitted to the ICU. However, our results show that when comparing cohorts with similar comorbidity burden, a previous cardiopathy “per se” does not significantly increase the risk of death in patients with a concomitant COVID infection.

Funding Acknowledgement

Type of funding sources: None. Mortality unmatched vs matched cohort

Endotrophin is significantly associated with disease severity and increased risk of adverse outcome in HFpEF but not in HFrEF patients

Introduction

The global burden of heart failure (HF), with either reduced (HFrEF) or preserved (HFpEF) ejection fraction, has increased dramatically over the past years, and HFpEF is projected to become the dominant type of HF. Fibrogenesis, promoted by fibroblast activity, plays an important role in the pathology of HF regardless of subtype, causing impaired cardiac function. Endotrophin is a bioactive molecule released from collagen type VI during its maturation, and it is a marker of fibroblast activity. The aim of this post-hoc analysis was to confirm the previously observed prognostic potential of endotrophin (measured by PRO-C6) for adverse outcome in HFpEF and to test its prognostic abilities in HFrEF.

Methods

234 patients with hypertension and either HFrEF (30.3%) or HFpEF (69.7%) were included for analysis. 43.2% were NYHA Class II, 52.5% NYHA Class III and 2.5% NYHA Class IV. 53.4% of patients had a previous history of atrial fibrillation. The cohort did not include diabetic patients. Cardiac function was assessed by echocardiography and standard clinical measures, including left ventricle ejection fraction (EF), blood pressure (BP) and measurement of N-terminal natriuretic brain-peptide (NT-proBNP). Circulating endotrophin was quantified at baseline in serum by means of an enzyme-linked immunosorbent assay, PRO-C6.

Results

PRO-C6 levels increased significantly with disease severity in HFpEF patients (NYHA Class III vs II, p=0.0003), but not in HFrEF patients (NYHA Class III vs II, p=0.33). In HFpEF patients, PRO-C6 was able to discriminate between patients that were hospitalized for HF (AUC=0.69, p&lt;0.001), died from cardiovascular (CV) causes (AUC=0.74, p&lt;0.001), or by any other cause (AUC=0.73, p&lt;0.001). PRO-C6 was not associated with none of these outcomes in HFrEF patients (AUC=0.56, p=0.42; AUC=0.53, p=0.73; AUC=0.56, p=0.53, respectively). Adding PRO-C6 to a risk prediction model containing age, sex, body mass index and systolic BP significantly increased the discriminatory power of the model for mortality (deltaAUC=0.037, p=0.04). When looking at patients stratified in PRO-C6 tertiles, patients in the upper tertile had a significantly higher risk of mortality (p&lt;0.0001, hazard ratios 3 vs 1=4.1, 3 vs 2=3.5, respectively) and HF hospitalization (p&lt;0.0001, hazard ratio 3 vs 1=4.4, 3 vs 2=1.6, respectively) compared to tertiles 1 and 2.

Conclusion

In this population of hypertensive HF patients, circulating endotrophin, measured by PRO-C6, was increased with increasing disease severity, and associated with a higher risk of adverse outcome in HFpEF, but not in HFrEF patients. The data presented here suggest a potential role of endotrophin in HFpEF pathophysiology and further underline the differences between HFpEF and HFrEF. These data confirm previous observations, and strengthen the usefulness of endotrophin, measured by the PRO-C6 biomarker, as a prognostic tool aiding in assessment of HFpEF patients.

Funding Acknowledgement

Type of funding sources: None.

Prognostic factors at admission on patients with cancer and COVID-19: Analysis of HOPE registry data

Background

Previous works seem to agree in the higher mortality of cancer patients with COVID-19. Identifying potential prognostic factors upon admission could help identify patients with a poor prognosis.

Methods

We aimed to explore the characteristics and evolution of COVID-19 cancer patients admitted to hospital in a multicenter international registry (HOPE COVID-19).

Our primary objective is to define those characteristics that allow us to identify cancer patients with a worse prognosis (mortality within 30 days after the diagnosis of COVID-19).

Results

5838 patients have been collected in this registry, of whom 770 had cancer among their antecedents. In hospital mortality reached 258 patients (33.51%). The median was 75 years (65–82). Regarding the distribution by sex, 34.55% of the patients (266/770) were women.

The distribution by type of cancer: genitourinary 238/745 (31.95%), digestive 124/745 (16.54%), hematologic 95/745 (12.75%).

In multivariate regression analysis, factors that are independently associated with mortality at admission are: renal impairment (OR 3.45, CI 97.5% 1.85–6.58), heart disease (2.32, 1.47–3.66), liver disease (4.69, 1.94–11.62), partial dependence (2.41, 1.34–4.33), total dependence (7.21, 2.60–21.82), fatigue (1.84, 1.16–2.93), arthromialgias (0.45, 0.26–0.78), SatO2 < 92% (4.58, 2.97–7.17), elevated LDH (2.61, 1.51–4.69) and abnormal decreased Blood Pressure (3.57, 1.81–7.15). Analitical parameters are also significant altered.

Conclusion

In patients with cancer from the HOPE registry, 30-day mortality from any cause is high and is associated with easily identifiable clinical factors upon arrival at the hospital. Identifying these patients can help initiate more intensive treatments from the start and evaluate the prognosis of these patients.

Splicing machinery is impaired in rheumatoid arthritis, associated with disease activity and modulated by anti-TNF therapy

OBJECTIVES

To characterise splicing machinery (SM) alterations in leucocytes of patients with rheumatoid arthritis (RA), and to assess its influence on their clinical profile and therapeutic response.

METHODS

Leucocyte subtypes from 129 patients with RA and 29 healthy donors (HD) were purified, and 45 selected SM elements (SME) were evaluated by quantitative PCR-array based on microfluidic technology (Fluidigm). Modulation by anti-tumour necrosis factor (TNF) therapy and underlying regulatory mechanisms were assessed.

RESULTS

An altered expression of several SME was found in RA leucocytes. Eight elements (SNRNP70, SNRNP200, U2AF2, RNU4ATAC, RBM3, RBM17, KHDRBS1 and SRSF10) were equally altered in all leucocytes subtypes. Logistic regressions revealed that this signature might: discriminate RA and HD, and anti-citrullinated protein antibodies (ACPAs) positivity; classify high-disease activity (disease activity score-28 (DAS28) >5.1); recognise radiological involvement; and identify patients showing atheroma plaques. Furthermore, this signature was altered in RA synovial fluid and ankle joints of K/BxN-arthritic mice. An available RNA-seq data set enabled to validate data and identified distinctive splicing events and splicing variants among patients with RA expressing high and low SME levels. 3 and 6 months anti-TNF therapy reversed their expression in parallel to the reduction of the inflammatory profile. In vitro, ACPAs modulated SME, at least partially, by Fc Receptor (FcR)-dependent mechanisms. Key inflammatory cytokines further altered SME. Lastly, induced SNRNP70-overexpression and KHDRBS1-overexpression reversed inflammation in lymphocytes, NETosis in neutrophils and adhesion in RA monocytes and influenced activity of RA synovial fibroblasts.

CONCLUSIONS

Overall, we have characterised for the first time a signature comprising eight dysregulated SME in RA leucocytes from both peripheral blood and synovial fluid, linked to disease pathophysiology, modulated by ACPAs and reversed by anti-TNF therapy.

Ruminiclostridium 5, Parabacteroides distasonis, and bile acid profile are modulated by prebiotic diet and associate with facilitated sleep/clock realignment after chronic disruption of rhythms

Chronic disruption of rhythms (CDR) impacts sleep and can result in circadian misalignment of physiological systems which, in turn, is associated with increased disease risk. Exposure to repeated or severe stressors also disturbs sleep and diurnal rhythms. Prebiotic nutrients produce favorable changes in gut microbial ecology, the gut metabolome, and reduce several negative impacts of acute severe stressor exposure, including disturbed sleep, core body temperature rhythmicity, and gut microbial dysbiosis. In light of previous compelling evidence that prebiotic diet broadly reduces negative impacts of acute, severe stressors, we hypothesize that prebiotic diet will also effectively mitigate the negative impacts of chronic disruption of circadian rhythms on physiology and sleep/wake behavior. Male, Sprague Dawley rats were fed diets enriched in prebiotic substrates or calorically matched control chow. After 5 weeks on diet, rats were exposed to CDR (12 h light/dark reversal, weekly for 8 weeks) or remained on undisturbed normal light/dark cycles (NLD). Sleep EEG, core body temperature, and locomotor activity were recorded via biotelemetry in freely moving rats. Fecal samples were collected on experimental days -33, 0 (day of onset of CDR), and 42. Taxonomic identification and relative abundances of gut microbes were measured in fecal samples using 16S rRNA gene sequencing and shotgun metagenomics. Fecal primary, bacterially modified secondary, and conjugated bile acids were measured using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Prebiotic diet produced rapid and stable increases in the relative abundances of Parabacteroides distasonis and Ruminiclostridium 5. Shotgun metagenomics analyses confirmed reliable increases in relative abundances of Parabacteroides distasonis and Clostridium leptum, a member of the Ruminiclostridium genus. Prebiotic diet also modified fecal bile acid profiles; and based on correlational and step-wise regression analyses, Parabacteroides distasonis and Ruminiclostridium 5 were positively associated with each other and negatively associated with secondary and conjugated bile acids. Prebiotic diet, but not CDR, impacted beta diversity. Measures of alpha diversity evenness were decreased by CDR and prebiotic diet prevented that effect. Rats exposed to CDR while eating prebiotic, compared to control diet, more quickly realigned NREM sleep and core body temperature (ClockLab) diurnal rhythms to the altered light/dark cycle. Finally, both cholic acid and Ruminiclostridium 5 prior to CDR were associated with time to realign CBT rhythms to the new light/dark cycle after CDR; whereas both Ruminiclostridium 5 and taurocholic acid prior to CDR were associated with NREM sleep recovery after CDR. These results support our hypothesis and suggest that ingestion of prebiotic substrates is an effective strategy to increase the relative abundance of health promoting microbes, alter the fecal bile acid profile, and facilitate the recovery and realignment of sleep and diurnal rhythms after circadian disruption.

Modulation of cell physiology under hypoxia in pancreatic cancer

In solid tumors, the development of vasculature is, to some extent, slower than the proliferation of the different types of cells that form the tissue, both cancer and stroma cells. As a consequence, the oxygen availability is compromised and the tissue evolves toward a condition of hypoxia. The presence of hypoxia is variable depending on where the cells are localized, being less extreme at the periphery of the tumor and more severe in areas located deep within the tumor mass. Surprisingly, the cells do not die. Intracellular pathways that are critical for cell fate such as endoplasmic reticulum stress, apoptosis, autophagy, and others are all involved in cellular responses to the low oxygen availability and are orchestrated by hypoxia-inducible factor. Oxidative stress and inflammation are critical conditions that develop under hypoxia. Together with changes in cellular bioenergetics, all contribute to cell survival. Moreover, cell-to-cell interaction is established within the tumor such that cancer cells and the microenvironment maintain a bidirectional communication. Additionally, the release of extracellular vesicles, or exosomes, represents short and long loops that can convey important information regarding invasion and metastasis. As a result, the tumor grows and its malignancy increases. Currently, one of the most lethal tumors is pancreatic cancer. This paper reviews the most recent advances in the knowledge of how cells grow in a pancreatic tumor by adapting to hypoxia. Unmasking the physiological processes that help the tumor increase its size and their regulation will be of major relevance for the treatment of this deadly tumor.

Consistent evidence of indirect effects of impulsive delay discounting and negative urgency between childhood adversity and adult substance use in two samples

RATIONALE

Exposure to adverse life experiences (ACEs) is robustly associated with problematic alcohol and other drug use. In addition, both ACEs and substance use have been independently associated with impulsivity.

OBJECTIVE

To examine whether impulsivity is implicated in the link between ACE and adult substance use in two samples.

METHODS

The primary sample was a cohort of community adults (N = 1431) who completed a one-time in-person assessment. A second sample was crowdsourced using Amazon Mechanical Turk (N = 3021). All participants were assessed for ACEs using the Adverse Childhood Experience Questionnaire and for current alcohol and other drug use. Given its multidimensional nature, impulsivity was assessed using the UPPS-P measure of impulsive personality traits, Go/NoGo (GNG) task (in-person community adult sample only), and delay discounting (Monetary Choice Questionnaire [MCQ] in the community adults and Effective Delay-50 [ED₅₀] in the crowdsourced sample. Structural equation modeling was used to examine the hypothesized indirect effects for the measures of impulsivity between ACEs and substance use.

RESULTS

In the community adults, significant indirect effects were observed from ACEs to substance use via UPPS-Negative Urgency (β = 0.07, SE = 0.02, 95% CI [0.04, 0.10]), and the MCQ (β = 0.02 SE = .01, 95% CI [0.01, 0.03]). In the crowdsourced sample, significant indirect effects were observed from ACEs to substance use via UPPS-Negative Urgency (β = 0.05, SE = .01, 95% CI [0.04, 0.07]), UPPS-Premeditation (β = 0.04, SE = .01, 95% CI [0.02, 0.05), and the ED₅₀ (β = 0.02, SE = .01; 95% CI [0.01, 0.03]).

CONCLUSION

These findings provide consistent evidence that decrements in regulation of negative emotions and overvaluation of immediate rewards indirectly link ACE and substance use. These robust cross-sectional findings support the need for elucidating the underlying neural substrates implicated and for longitudinal evaluations.

POS0185 IDENTIFICATION AND VALIDATION OF TWO NOVEL SERUM BIOMARKERS ASSOCIATED WITH THE SEROLOGICAL STATUS OF RHEUMATOID ARTHRITIS PATIENTS

Background:

Despite the diagnostic value of Rheumatoid Factor (RF) and Anti-Citrullinated Protein Antibodies (ACPA), more serological markers are needed in order to improve early diagnosis and treatment response of the Rheumatoid Arthritis (RA) patients. Increased knowledge about how these two major autoreactivities arise is crucial for understanding how RA develops and what mechanisms drive pathogenesis.

Objectives:

We aimed to investigate, using a proteomic strategy, novel protein biomarkers associated with RF and/or ACPA that might be useful to stratify seropositive and seronegative RA patients.

Methods:

A shotgun proteomic analysis was performed on 80 sera from the RA cohort of the Rheumatology Unit of the University Hospital of Santiago de Compostela (CHUS). Sera were classified as seropositive or seronegative according to their RF and ACPA values, and were then analyzed employing the iTRAQ labelling technique (Sciex) followed by LC-MALDI-MS/MS analysis (MALDI-TOF). A Multiple Reaction Monitoring (MRM) method was subsequently developed using the Skyline Software for the simultaneous quantification of 26 peptides belonging to ten putative protein biomarkers. The quantitative targeted analysis was performed using peptides with isotope labelled amino acids as internal standards. Serum levels of orosomucoid 1 (ORM1) and haptoglobin (HPT) were measured using commercially available ELISA Kits in the whole RA cohort (n=260) from the Rheumatology Unit of the University Hospital of A Coruña (HUAC).

Results:

For the initial screening, eighty sera were grouped according to the ACPA/RF status in 4 pools (20 patients/pool). Using an iTRAQ technology-based quantitative proteomic approach, the abundance of eleven proteins was altered in the sera from ACPApos/RFpos, 13 proteins in ACPAneg/RFpos and 12 proteins in ACPApos/RFneg, compared to ACPAneg/RFneg. Vitamin D binding protein (VTDB) was the unique protein that resulted increased in all the comparisons. For the biomarker verification phase, all the samples from the CHUS cohort were analyzed individually (n=80). Using the MRM technology, 26 peptides belonging to ten putative protein biomarkers associated with double positivity were simultaneously quantified. The statistical analysis showed a significant modulation of 9 peptides (belonging to 4 different proteins) in ACPApos/RFpos, 7 peptides (5 proteins) in ACPAneg/RFpos, and 9 peptides (6 proteins) in ACPApos/RFneg compared to ACPAneg/RFneg (p<0.05). Two acute phase reactants (ORM1 and HPT) displayed the same modulation in both screening and verification phases, thus confirming their association with the double positivity. Finally, in the biomarker validation phase, a total of 260 patients from CHUAC were included (Table 1). RA patients were classified as follows: (1) 112 patients (43.1%) were ACPApos/RFpos; (2) 73 patients (28.1%) were ACPAneg/RFneg; (3) 51 patients (19.6%) were ACPAneg/RFpos; and (4) 24 patients (9.2%) were ACPApos/RFneg. Serum levels of ORM1 and HPT (Figure 1), measured by commercial immunoassays, confirmed their increased values in double seropositive patients (p=0,0053 ORM1; p=0,0026 HPT). Finally, the increased level of ORM1 resulted associated with RF rather than ACPA status (p=0,0008 ACPAneg/RFpos); whereas HPT was associated with ACPA rather than RF status (p=0,0112 ACPApos/RFneg).

Table 1.

The different phases of RA biomarker development followed in this study.

DISCOVERYPHASEVERIFICATIONPHASEVALIDATIONPHASESource centerCHUSCHUSCHUACN° ofsamplesn= 4n= 80n= 260ACPA+RF+Pool 1ACPA+RF+20ACPA+RF+112ACPA-RF-Pool 2ACPA-RF-20ACPA-RF-73ACPA-RF+Pool 3ACPA-RF+20ACPA-RF+51ACPA+RF-Pool 4ACPA+RF-20ACPA+RF-24N° ofbiomarkersORM1, ORM2, HPT, A2GL, AACT, RBP4, PLMN, IC1, VDBP, APOBORM1, HPT, A2GL, AACTORM1, HPTFigure 1.

Conclusion:

The determination of ORM1 and HPT in sera provides novel information useful for patient stratification, which might improve diagnostic and prognostic approaches and facilitate the development of personalized medicine strategies in RA.

Acknowledgements:

This work is supported by grants from Fondo de Investigación Sanitaria (RD16/0012/0002, PT17/0019/0014) integrated in the National Plan for Scientific Program, Development and Technological Innovation 2013–2016 and funded by the ISCIII-General Subdirection of Assessment and Promotion of Research-European Regional Development Fund (FEDER) “A way of making Europe”.

Disclosure of Interests:

None declared