Myocardial work analysis for early detection of type 1 CTRCD and patient risk stratification

Aim

This prospective longitudinal study analyses the potential role of Myocardial Work in early detection of cardiotoxicity during chemotherapy and its added value for prognosis and patients' risk stratification.

Methods

We enrolled 47 consecutive female patients with HER2-positive breast cancer referred for anti-cancer therapy based on anthracycline and taxane. Patients with depressed LV function at baseline were excluded. Medical therapy, clinical parameters and echocardiographic data were recorded at baseline and at 3, 6, 12 months follow-up. Additionally, cuff blood pressure was measured at the time of 2D-TTE examination and adequate echocardiographic images were stored for off-line analysis.

Results

CTRCD was detected in 17 patients (36%) while 30 patients remained free of CTRCD (64%). There were no intergroup differences for age, body mass index, resting heart rate and brachial arterial pressure. Both groups presented unaltered LV systolic function after 3 months follow-up yet overt cardiac dysfunction showed up in the CTRCD group at 6 months with significant decline in LVEF, GLS, MWI, MWE and CW from baseline values (LVEF, %: 56.0±4.1 vs 52.2±6.5; GLS, %: −20.9±1.9 vs −17.6±3.2; MWI, mmHg%: 2125±348 vs 1704±620; MWE, %: 95±2.6 vs 93±3.9 and CW, mmHg%: 2562±3567 vs 2212±455, p<0.05). Additionally, GLS, MWI and MWE at 6 months were significantly worse in the CTRCD group vs non-CTRCD group (GLS, %: −17.6±3.2 vs −20.6±1.8; MWI, mmHg%: 1704±620 vs 2087±347; MWE, %: 93±3.9 vs 96±1.5, p<0.05). Depressed LV systolic function persisted after 1 year follow-up (Figure 1). After 3 months, only de relative change in GLS and WW from baseline were significantly worse in CTRCD vs non-CTRCD (ΔGLS: +3.7±11 vs −3.9±10, ΔWW: +46.1±83 vs +2.2±45). Whereas no correlation was found, the combination of both ΔGLS and ΔWW at 3 months showed stronger prognostic value for CTRCD than each parameter alone, AUC of 0.72 (Figure 2).

Conclusion

These findings point the superiority of Myocardial Work for early type 1 CTRCD detection in comparison to the current diagnostic tools. Additionally, we suggest the add-on value of ΔWW on top of ΔGLS quantification for better patient risk stratification. These are promising results for better clinical surveillance of cardiac function during cancer treatment.

Funding Acknowledgement

Type of funding sources: None.

Genetic background of pediatric PAH in Spain and its clinical implications: data from the REHIPED Spanish Registry

Background

The genetic background of pulmonary arterial hypertension (PAH) in the Spanish pediatric population could be different from the genetic background described in other countries. Besides, clinical implications of a positive genetic result in the PAH pediatric population are not fully understood yet, and could result in the “reclassification” of patients from one PAH group to another type among the current pediatric classification.

Material and methods

Patients under 19 years at diagnosis included in the REHIPED registry from January 2011 to December 2021 were included. Clinical variables and genetical results were recorded. Succesive NGS panels involving up to 35 genes were used. After the results of the genetic testing, we analyzed differences in survival, and if patients “moved” to another category in the current Nice classification.

Results

In the selected cohort of 98 patients (56.1% female), median age at diagnosis was 7.1 years (IQr 1.5–14.7), and ethnicity as follows: Caucasian (81.6%), Romani (8.2%), others (10.2%) (Table 1). Before the genetic testing, patients had been classified as Idiopathic (53.1%), Congenital Heart Disease-PAH (30.6%), Heritable (5.1%), Pulmonary veno-oclusive disease (PVOD) 6.1%, and Multisystemic disorder associated with PAH (5.1%). Pathogenic or likely pathogenic variants were found in 44 of the screened patients (44.9%): BMPR2 (12 cases), EIF2AK4 (9), TBX4 (n=4), MECP2 (n=3), KCNK3 (n=2), FOXF1 (n=2), NFU1 (N=4), ACVRL1 (n=1), BMPR1B (n=1), CLBCI (n=1), GBE1 (n=1), GDF2 (n=1), SOX17 (n=1), VHL (n=1), and digenic pathogenic variant in ABCC8/SMAD1 (n=1). After genetic analysis, 28 patients (28.6%) were “reclassified” (Fig. 1, panel A), with HPAH, PVOD and multisystemic disorders increasing up to 18.4%, 8.2%, and 12.2%, respectively. Worse Survival from death or lung transplantation was observed in heritable PVOD and multisystemic disorders (Fig. 1, panel B).

Conclusions

The Spanish pediatric PAH population showed higher prevalence of EIF2AK4 than other pediatric registries. Genetic testing resulted in the “reclassification” of a significant number of patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Rio Hortega grant from the Spanish Ministry of Science and Innovation (Instituto de Salud Carlos III).

Global longitudinal strain and NT-proBNP as predictors for LV function recovery after TAVR

Introduction

Abnormal GLS values as well as high plasma levels of NT-proBNP previous to TAVR are independent predictors for higher peri-procedural mortality. Moreover, in a subgroup of TAVR patients LV function does not recover following the procedure. Until today, it is still unclear how to predict impaired post-procedural LV function for optimal clinical patient's management.

Purpose

This study was set up to assess the predictive value of baseline GLS and NT-proBNP levels on LV function recovery (LVfr) in a cohort of patients with severe AS referred for TAVR.

Methods

A total of 25 patients (9 male, 84±5 yo, EF 50±11%) with severe AS (AVA 0.6±0.3 cm2, MPG 49±16 mmHg) referred for TAVR were included. Blood analysis and TTE were performed before intervention (baseline, bl) and at follow-up (fu). Myocardial work was analysed offline integrating the longitudinal strain and afterload pressure (SBP + AVPmean). LVfr was defined as GLS <−19% at fu. The median values at bl of NT-proBNP (1781 ng/L) and GLS (−15%) were taken as cut-off to categorize patients in 4 groups: NT-proBNPhighGLShigh, NT-proBNPlowGLShigh, NT-proBNPhighGLSlow and NT-proBNPlowGLSlow. The ROC curve analysis for prediction of LVfr after TAVR were performed.

Results

LV function recovered in 13 patients (52%). Despite similar EF and global MWI after TAVR, the LV contraction became more efficient as evidenced by a significant improvement (bl vs fu, p<0.05) in GLS (−14±4.5 vs −18±4.2%), MWW (400±510 vs 157±107 mmHg%) MWE (88±6 vs 92±6%) together with a reduction in afterload pressure (203±38 vs 156±22 mmHg, p<0.05). In the NT-proBNPlow groups, GLS (−15±4 vs −20±3%, p<0.05) and MCW (2166±874 vs 2978±634 mmHg%, p<0.05) at fu were significantly better when compared to the NT-proBNPhigh groups. Likewise, the GLSlow groups showed higher EF (47±10 vs 54±6%, p<0.05) and MCW (2181±832 vs 2961±715 mmHg%, p<0.05) than the GLShigh groups at fu. Interestingly, the GLSlow groups had lower LVESV (57±38 vs 29±10 ml, p<0.05) and LVEDV (113±49 vs 80±20 ml, p<0.05) post-TAVR than the GLShigh groups which suggests a positive remodelling following afterload reduction. At the ROC curve analysis, combined GLS and NT-proBNP at bl were better predictors for LVfr than each parameter alone, AUC 0.86 (Fig. 1). Additionally, only 20% LVfr was seen in the NT-proBNPhighGLShigh group in contrast to 67–75% in the other groups.

Conclusion

Elevated afterload in severe AS leads to a physiological reduction of GLS. Although the decrease in afterload after TAVR beneficially affects GLS and may lead to LVfr, this was not observed in a subgroup of patients with high NT-proBNP levels in whom GLS remained impaired at follow-up. We speculate that myocardial tissue damage and fibrosis due to long lasting high pressure exposure may partly be responsible for this observation. The combination of pre-procedural NT-proBNP levels and GLS shows strong predictive potential for LVfr after TAVR and larger studies are warranted for further evaluation and cut-off values determination.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Cardiovascular Research Center Aalst (npo)

Performance of non-invasive myocardial work to predict the first hospitalization for de novo heart failure with preserved ejection fraction (HFpEF)

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Dr. Paolisso, Dr. Esposito, Dr. Fabbricatore are supported by a research grant from the CardioPaTh PhD Program of University of Naples Federico II

Background

Non-invasive myocardial work (MW) is a validated index of left ventricular (LV) systolic performance, incorporating afterload and myocardial metabolism. The role of MW in predicting the first hospitalization for de novo heart failure with preserved ejection fraction (HFpEF) is still unknown.

Purpose

To investigate the diagnostic performance of MW to predict the first de novo HFpEF hospitalization in ambulatory individuals with preserved LVEF.

Methods

Twenty-nine patients with trans-thoracic echocardiography performed at least 6 months before the first HFpEF hospitalization were compared with 29 matched controls. MW was derived as the area of pressure-strain loop using speckle-tracking and brachial artery blood pressure. Global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) were collected. First HFpEF hospitalization and its combination with cardiovascular death (MACE) and all-cause of death (MAE) were assessed.

Results

At baseline, future HFpEF patients showed lower GWI, GCW, GWE and higher GWW than controls (all p < 0.05).  At admission versus baseline, GWE significantly decreased, and GWW increased in the HFpEF group (p < 0.05), whereas no significant difference was observed in the controls over time. GWW, with a cut-off of 170 mmHg%, showed the largest AUC to predict first HFpEF hospitalization (AUC = 0.80, 95% CI 0.69–0.91, p < 0.001), MACE (AUC = 0.80, 95% CI 0.66–0.90, p < 0.001) and MAE (AUC = 0.79, 95% CI 0.62–0.88, p = 0.001). GWW > 170 mmHg% was associated with a 4-fold increase of MACE (HR = 4.5, 95% CI 1.59–13.12, p = 0.005) and a 3-fold higher risk of MAE (HR = 2.9, 95% CI 1.24–6.6, p = 0.014).

Conclusions

In ambulatory patients with preserved LVEF and risk factors, GWW showed high accuracy to predict the first HFpEF hospitalization and its combination with mortality. The GWW routine assessment may be clinically helpful in patients with dyspnea. Abstract Figure 1: Serial changes of LARs, LV GLS  Abstract Figure 2:Kaplan–Meier survival curves fo

Obesity status and obesity-associated gut dysbiosis effects on hypothalamic structural covariance

BACKGROUND

Functional connectivity alterations in the lateral and medial hypothalamic networks have been associated with the development and maintenance of obesity, but the possible impact on the structural properties of these networks remains largely unexplored. Also, obesity-related gut dysbiosis may delineate specific hypothalamic alterations within obese conditions. We aim to assess the effects of obesity, and obesity and gut-dysbiosis on the structural covariance differences in hypothalamic networks, executive functioning, and depressive symptoms.

METHODS

Medial (MH) and lateral (LH) hypothalamic structural covariance alterations were identified in 57 subjects with obesity compared to 47 subjects without obesity. Gut dysbiosis in the subjects with obesity was defined by the presence of high (n = 28) and low (n = 29) values in a BMI-associated microbial signature, and posthoc comparisons between these groups were used as a proxy to explore the role of obesity-related gut dysbiosis on the hypothalamic measurements, executive function, and depressive symptoms.

RESULTS

Structural covariance alterations between the MH and the striatum, lateral prefrontal, cingulate, insula, and temporal cortices are congruent with previously functional connectivity disruptions in obesity conditions. MH structural covariance decreases encompassed postcentral parietal cortices in the subjects with obesity and gut-dysbiosis, but increases with subcortical nuclei involved in the coding food-related hedonic information in the subjects with obesity without gut-dysbiosis. Alterations for the structural covariance of the LH in the subjects with obesity and gut-dysbiosis encompassed increases with frontolimbic networks, but decreases with the lateral orbitofrontal cortex in the subjects with obesity without gut-dysbiosis. Subjects with obesity and gut dysbiosis showed higher executive dysfunction and depressive symptoms.

CONCLUSIONS

Obesity-related gut dysbiosis is linked to specific structural covariance alterations in hypothalamic networks relevant to the integration of somatic-visceral information, and emotion regulation.

Simulating the impact of non-pharmaceutical interventions limiting transmission in COVID-19 epidemics using a membrane computing model

Epidemics caused by microbial organisms are part of the natural phenomena of increasing biological complexity. The heterogeneity and constant variability of hosts, in terms of age, immunological status, family structure, lifestyle, work activities, social and leisure habits, daily division of time and other demographic characteristics make it extremely difficult to predict the evolution of epidemics. Such prediction is, however, critical for implementing intervention measures in due time and with appropriate intensity. General conclusions should be precluded, given that local parameters dominate the flow of local epidemics. Membrane computing models allows us to reproduce the objects (viruses and hosts) and their interactions (stochastic but also with defined probabilities) with an unprecedented level of detail. Our LOIMOS model helps reproduce the demographics and social aspects of a hypothetical town of 10 320 inhabitants in an average European country where COVID-19 is imported from the outside. The above-mentioned characteristics of hosts and their lifestyle are minutely considered. For the data in the Hospital and the ICU we took advantage of the observations at the Nursery Intensive Care Unit of the Consortium University General Hospital, Valencia, Spain (included as author). The dynamics of the epidemics are reproduced and include the effects on viral transmission of innate and acquired immunity at various ages. The model predicts the consequences of delaying the adoption of non-pharmaceutical interventions (between 15 and 45 days after the first reported cases) and the effect of those interventions on infection and mortality rates (reducing transmission by 20, 50 and 80%) in immunological response groups. The lockdown for the elderly population as a single intervention appears to be effective. This modeling exercise exemplifies the application of membrane computing for designing appropriate multilateral interventions in epidemic situations.

Role of myocardial work index in early detection of cardiotoxicity in breast cancer patient

Introduction

Breast cancer patients receiving anthracyclines are particularly prone to develop cancer therapeutics-related cardiac dysfunction. Early detection of cardiotoxicity onset is required for optimal timing of cardio protection treatment. The latest guidelines consider a relative reduction of 15% in global longitudinal strain (GLS) from baseline as risk for cardiotoxicity. Nevertheless, the more recent Myocardial Work Index (MWI) offers a load-independent tool for detection of subclinical heart failure (HF). However, data in cancer patients are still scarce.

Purpose

This study analyses the predictive value of MWI for cardiotoxicity diagnosis after 6 months chemotherapy.

Methods

The study population consists of breast cancer patients referred for chemotherapy with anthracyclines and taxanes. Patients with a history of HF previous to chemotherapy or depressed LV function at baseline were excluded. Echocardiography was performed before onset of the chemotherapy (baseline) and after 6 months follow-up. LVEF, GLS and MWI were assessed offline using EchoPAC software. The values at baseline and 6 months follow-up were pairwise compared to detect subclinical cardiac dysfunction. LVEF, GLS and MWI means at baseline were taken as cut-off to compare the predictive value of each parameter. Moreover, patients were categorized in one group with GLS reduction >15% (Group 1) and one group with GLS reduction <15% (Group 2).

Results

From April 2016 to July 2020, 28 women with breast cancer were included (age 54±11 years, LVEF 58±4%, GLS −21±2%, MWI 2160±308 mmHg). All patients underwent the same standard chemotherapy protocol (4xEC, 12xTaxol). No difference in baseline characteristics between group 1 (n=13) and group 2 (n=15) was observed. At 6 months follow up a significant decrease in LVEF (53±8%, p=0.003), GLS (−19±3%, p=0.002) and MWI (1920±391 mmHg, p=0.005) was shown without any change in blood pressure. However, while mean LVEF and GLS at baseline did not predict any significant change, patients with MWI under the mean value at baseline (n=15) presented significant lower LVEF (50±8 vs 57±6% p=0.006), GLS (−17±3 vs −20±2%, p=0.01), MWI (1733±320 vs 2136±362 mmHg, p=0.005) after 6 months. Additionally, both groups had similar MWI at baseline (2148±335 mmHg vs 2170±294 mmHg, p=0.85), whereas those patients with GLS reduction >15% showed significant lower MWI after 6 months (1694±332 mmHg vs 2116±334 mmHg, p=0.003, Figure 1).

Conclusions

At 6 months follow up, a decline of the LV systolic function as side effect of chemotherapy can be seen. MWI at baseline shows the best predictive value for development of cardiotoxicity, in comparison to LVEF and GLS. Further studies are warranted to better understand the role of MWI for early detection of cardiotoxicity and its clinical relevance.

Funding Acknowledgement

Type of funding sources: Private hospital(s). Main funding source(s): Onze-Lieve-Vrouw hospital in Aalst (Belgium)

Genetic background in pediatric pulmonary arterial hypertension. Should we change the current recommendations for genetic testing?

Background

Pulmonary arterial hypertension (PAH) is a rare and severe disease, genetically predisposed in a high proportion of patients. PAH is subclassified in different subtypes depending on the underlying condition. Gene variants are more frequent among heritable or idiopathic forms. Nevertheless, pathogenic variants have been described across the entire spectrum of this disease. Evidence regarding genetics in pediatric PAH is scarce [1].

Purpose

Our aim is to describe the prevalence of significant gene mutations among a pediatric PAH cohort and to define specific data in the different subtypes.

Methods

Samples for genetic studies were obtained from blood tests of patients included in the Spanish National Registry of Pediatric Pulmonary Hypertension (REHIPED). Guardians signed informed consent before the inclusion in the study. Qualitative variables were compared by Chi-square test. Quantitative variables were assessed by Kruskal-Wallis, considering the asymmetric distribution of variables. STATA 14.0 was used for analyses.

Results

Sixty four patients were included between 2011 and 2021. Median age of the entire sample was 7.1 years (2.0–12.6) and 42.2% of them were male. There were significant differences in the age at diagnosis and race between the different included groups (table). Pathogenic or likely pathogenic variants were more frequent in familial pulmonary venooclusive disease (PVOD) and familial PAH cases. A similar percentage of mutations were found in idiopathic cases and in PAH associated with congenital heart disease (Figure). Gene variants in the gene encoding the bone morphogenetic protein receptor type 2 (BMPR2) were the most frequent mutations in the PAH familial cohort and there was also the most frequent finding in congenital heart disease and sporadic PAH, in conjunction with the TBX4 gene. Homozygous or compound heterozygous EIF2AK4 (eukaryotic translation initiation factor 2 a kinase 4) mutations were found in all the patients diagnosed with PVOD. Heritable PAH and PVOD cases were diagnosed more frequently after family screening.

Conclusions

This study shows a comparable proportion of pathogenic-likely pathogenic gene mutations in patients diagnosed of pulmonary arterial hypertension associated with congenital heart disease and idiopathic cases, with similar distribution of specific genes. BMPR2 and TBX 4 were the most frequent gene variants in this pediatric PAH population. BMPR2 and EIF2AK4 are the most common mutations in familial PAH and PVOD subtypes, respectively.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): ACU holds a Rio Hortega Grant from the Instituto de Salud Carlos III, Spanish Ministry of Science and Innovation.JAT and NG hold grants from FEDER (Federaciόn Española de Enfermedades Raras) and from the FCHP. Table 1. Characteristics of PAH subtypesFigure 1. PAH and ACMG classification.

The Significance of Genotypic Diversity in Coral Competitive Interaction: A Transcriptomic Perspective

Competitive interactions shape coral assemblages and govern the dynamics of coral ecosystems. Although competition is an ecological concept, the outcomes of competitive interactions are ultimately determined by patterns of gene expression. These patterns are subject to genotypic variation on both sides of any interaction. Such variation is typically treated as “noise”, but it is sometimes possible to identify patterns within it that reveal important hidden factors in an experiment. To incorporate genotypic variation into the investigation of coral competitive interactions, we used RNA-sequencing to study changes in gene expression in a hard coral (Porites cylindrica) resulting from non-contact competition experiment with a soft coral (Lobophytum pauciflorum). Hard coral genotype explained the largest proportion of variation between samples; however, it was also possible to detect gene expression changes in 76 transcripts resulting from interaction with the soft coral. In addition, we found a group of 20 short secreted proteins that were expressed as a coordinated unit in three interacting Porites-Lobophytum pairs. The presence of this secretion response was idiosyncratic in that it could not be predicted based on polyp behaviour, or the genotype of hard or soft coral alone. This study illustrates the significance of individual variation as a determinant of competitive behaviour, and also provides some intriguing glimpses into the molecular mechanisms employed by hard corals competing at a distance.

Myocardial work index: a novel tool for detection of early cardiotoxicity in breast cancer patient

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Cardiovascular Research Center Aalst, (Aalst, Belgium)

Introduction

Breast cancer patients receiving anthracyclines are particularly prone to develop cancer therapeutics-related cardiac dysfunction (CTRCD). Early detection of cardiotoxicity onset is required for optimal timing of cardio protection treatment. The latest guidelines consider a relative reduction of 15% in global longitudinal strain (GLS) from baseline as risk for cardiotoxicity. Nevertheless, the more recent Myocardial Work Index (MWI) offers a load-independent tool for detection of subclinical heart failure (HF). Data in cancer patients are still scarce. 

Purpose

This study analyses the predictive value of MWI for cardiotoxicity diagnosis after 6 months chemotherapy.

Methods

The study population consists of breast cancer patients referred for chemotherapy with anthracyclines and taxanes. Patients with a history of HF previous to chemotherapy or depressed LV function at baseline were excluded. Echocardiography was performed before onset of the chemotherapy (baseline) and after 6 months follow-up. LVEF, GLS and MWI were assessed offline using EchoPAC software. The values at baseline and 6 months follow-up were pairwise compared to detect subclinical cardiac dysfunction. Mean LVEF, GLS and MWI at baseline were taken as cut-off value to compare the predictive value of each parameter. Moreover, patients were categorized in one group with GLS reduction >15% (Group 1) and one group with GLS reduction <15% (Group 2).  

Results

From April 2016 to January 2020, 24 women with breast cancer were included (age 54 ± 11 years, LVEF 58 ± 4%, GLS -21 ± 2%, MWI 2181 ± 325 mmHg). All patients underwent the same standard chemotherapy protocol (4xEC, 12xTaxol). No difference in baseline characteristics between group 1 (n = 9) and group 2 (n = 15) was observed. At 6 months follow up a significant decrease in LVEF (53 ± 8%, p = 0.003), GLS (-19 ± 3%, p = 0.002) and MWI (1933 ± 410 mmHg, p = 0.005) was shown without any change in blood systolic pressure. However, while mean LVEF and GLS at baseline did not predict any significant change, patients with MWI under the mean value at baseline (n = 13) presented significant lower LVEF (49 ± 8%, p = 0.006), GLS (-18 ± 4%, p = 0.045), MWI (1753 ± 341 mmHg, p = 0.018) after 6 months. Additionally, both groups had similar MWI at baseline (2199 ± 390 mmHg vs 2170 ± 294 mmHg, p = 0.85), whereas those patients with GLS reduction >15% showed significant lower MWI after 6 months (1626 ± 344 mmHg vs 2116 ± 334 mmHg, p = 0.003, Figure 1).

Conclusions

At 6 months follow up, a decline of the LV systolic function as side effect of chemotherapy can be seen. In comparison to LVEF and GLS, MWI shows the best predictive value for development of early cardiotoxicity. Further studies are warranted to better understand the role of MWI in predicting CTRCD and its clinical relevance.

Abstract Figure. Change in MWI

AmAMP1 from Acropora millepora and damicornin define a family of coral-specific antimicrobial peptides related to the Shk toxins of sea anemones

A candidate antimicrobial peptide (AmAMP1) was identified by searching the whole genome sequence of Acropora millepora for short (<125AA) cysteine-rich predicted proteins with an N-terminal signal peptide but lacking clear homologs in the SwissProt database. It resembled but was not closely related to damicornin, the only other known AMP from a coral, and was shown to be active against both Gram-negative and Gram-positive bacteria. These proteins define a family of AMPs present in corals and their close relatives, the Corallimorpharia, and are synthesised as preproproteins in which the C-terminal mature peptide contains a conserved arrangement of six cysteine residues. Consistent with the idea of a common origin for AMPs and toxins, this Cys motif is shared between the coral AMPs and the Shk neurotoxins of sea anemones. AmAMP1 is expressed at late stages of coral development, in ectodermal cells that resemble the "ganglion neurons" of Hydra, in which it has recently been demonstrated that a distinct AMP known as NDA-1 is expressed.

Evidence for Succession and Putative Metabolic Roles of Fungi and Bacteria in the Farming Mutualism of the Ambrosia Beetle Xyleborus affinis

The bacterial and fungal community involved in ambrosia beetle fungiculture remains poorly studied compared to the famous fungus-farming ants and termites. Here we studied microbial community dynamics of laboratory nests, adults, and brood during the life cycle of the sugarcane shot hole borer, Xyleborus affinis We identified a total of 40 fungal and 428 bacterial operational taxonomic units (OTUs), from which only five fungi (a Raffaelea fungus and four ascomycete yeasts) and four bacterial genera (Stenotrophomonas, Enterobacter, Burkholderia, and Ochrobactrum) can be considered the core community playing the most relevant symbiotic role. Both the fungal and bacterial populations varied significantly during the beetle's life cycle. While the ascomycete yeasts were the main colonizers of the gallery early on, the Raffaelea and other filamentous fungi appeared after day 10, at the time when larval hatching happened. Regarding bacteria, Stenotrophomonas and Enterobacter dominated overall but decreased in foundresses and brood with age. Finally, inferred analyses of the putative metabolic capabilities of the bacterial microbiome revealed that they are involved in (i) degradation of fungal and plant polymers, (ii) fixation of atmospheric nitrogen, and (iii) essential amino acid, cofactor, and vitamin provisioning. Overall, our results suggest that yeasts and bacteria are more strongly involved in supporting the beetle-fungus farming symbiosis than previously thought.IMPORTANCE Ambrosia beetles farm their own food fungi within tunnel systems in wood and are among the three insect lineages performing agriculture (the others are fungus-farming ants and termites). In ambrosia beetles, primary ambrosia fungus cultivars have been regarded essential, whereas other microbes have been more or less ignored. Our KEGG analyses suggest so far unknown roles of yeasts and bacterial symbionts, by preparing the tunnel walls for the primary ambrosia fungi. This preparation includes enzymatic degradation of wood, essential amino acid production, and nitrogen fixation. The latter is especially exciting because if it turns out to be present in vivo in ambrosia beetles, all farming animals (including humans) are dependent on atmospheric nitrogen fertilization of their crops. As previous internal transcribed spacer (ITS) metabarcoding approaches failed on covering the primary ambrosia fungi, our 18S metabarcoding approach can also serve as a template for future studies on the ambrosia beetle-fungus symbiosis.

AB0492 INTESTINAL MICROBIOTA COMPOSITION OF PATIENT’S WITH BEHCET’S DISEASE: DIFFERENCES BETWEEN EYE, MUCOCUTANEOUS AND VASCULAR INVOLVEMENT (RHEUMA-BIOTA STUDY)

Background:

Recently, it has been shown that changes in microbiota composition play a role in the etiology and pathogenesis of chronic diseases. Changes in oral and intestinal microbiota diversity and composition are suggested in Behcet disease (BD), however there are no study available about the potential gut microbiota changes among different clinical forms of BD.

Objectives:

The aim of this study was to evaluate the intestinal microbiota composition of patient with BD and healthy controls, and also compare BD patients regarding to their eye, mucocutaneous and vascular involvement.

Methods:

In this prospective cohort study,27 patients diagnosed with BD and 10 aged and sex matched healthy controls were included. Patients with a body mass index> 35, who have used antibiotics or probiotics in the last 4 weeks, patients with chronic gastrointestinal or other systemic diseases, and those with acute / severe gastrointestinal symptoms requiring medical treatment were excluded from the study. For the intestinal microbiota analysis, gene amplification, library formation, sequence analysis and bioinformatic evaluation of the results were performed with 16SrRNA next generation sequencing methods with Illumina MiSeq.

Results:

There was no difference between the BD group and the control group in terms of alpha (Chao-1 and Shannon) and beta (Bray-Curtis) microbiota diversity indices (p> 0.05).Actinomyces, Libanicoccus, Collinsella, Eggerthella, Enetrohabdus, Catenibacterium and Enterobacterwere significantly higher in BD group compared to the control group. In addition,Bacteriodes, Cricetibacter, Alistipes, Lachnospira, Dielma, Akkermansia, Sutterella, Anaerofilum, Ruminococcease-UCG007, Acetanaerobacterium; and Copropaacterwere lower than the control group. There was no difference between the uveitis, mucocutaneous and vascular involvement groups in terms of alpha (Chao-1 and Shannon) and beta (Bray-Curtis) microbiota diversity and wealth indices (p> 0.05) while we obtained a significant p value of the beta diversity between three groups in weighted UniFrac PCoA (p<0.05). When we compared 3 three different system involvement (Eye, Mucocutaneous and Vascular), The LEfSe provides us with cladograms of six-level (from kingdom to genus). We found difference for the generaLachnospiraceae NK4A136in uveitis group,Dialister, İntestinomonas and Marvinbryantiain mucocutaneous group andGemellain vascular involvement group.

Conclusion:

There was a significant difference in the composition of intestinal microbiota in Behçet’s disease compared to healthy adults. We found also found the different clinical forms of Behcet’s disease have some different gut microbiota composition. Especially in Behçet’s disease, it will be useful to evaluateCatenibacterium, Collinsella and Eggerthellaincrease,Bacteroides and Akkermansiadecrease in larger series. In addition, due to the increase in theEggerthella lentastrain observed both in the FMF and Behcet patient group, it is useful to make more detailed metagenomic analyzes regarding the role of this agent in the etiopathogenesis and course of rheumatic diseases.

Disclosure of Interests:

None declared

AB1035 INTESTINAL MICROBIOTA COMPOSITION OF ADULT PATIENTS WITH FAMILIAL MEDITERRANEAN FEVER AND HEALTHY CONTROLS (THE RHEUMA-BIOTA STUDY)

Background:

Although Familial Mediterranean Fever (FMF) is a monogenic disease, microbiota composition may play role in the pathogenesis or phenotypic expression.

Objectives:

We aim to evaluate the intestinal microbiota composition in patients with FMF and to compare with healthy controls.

Methods:

In this prospective cohort study, a group of 10 adult patients with FMF and 10 age-appropriate healthy controls, for which there was strict inclusion/exclusion, were enrolled. Fecal samples were stored at -80°C until DNA extraction. A region of the 16S rRNA gene (V3-V4) was selected and sequencing was performed on the Illumina MiSeq platform at the Sequencing and Bioinformatics Service of FISABIO foundation.

Results:

Alpha and beta diversity tests were similar between FMF and control groups except that Chao1 index. Chao1 index was modestly decreased in FMF group comparing the healthy controls (p<0.05). Our results showed differences in the intestinal microbiota composition of patients with FMF, with a higher abundance ofEggerthella, at genus level. At species level,Eggerthella sinensisandEggerthella lentawere more abundant in patients with FMF.

Conclusion:

Eggerthella lentawas previously shown to be higher in type II diabetes, multiple sclerosis, rheumatoid arthritis and some disseminated infections. In this study we firstly showed abundance ofEggerthellain patients with FMF, especially inE. sinensisandE. lenta;in addition to. Whether any of observed associations are causal, or the direction of causality is unclear yet and further studies with patients with FMF at the first diagnosis might clarify this issue.

Disclosure of Interests:

None declared

Human milk mycobiota composition: relationship with gestational age, delivery mode, and birth weight

Intestinal and human milk microbiota studies during infancy have shown variations according to geographical location, delivery mode, gestational age, and mother-related factors during pregnancy. In this study, we performed metagenomic mycobiota analyses of 44 transient and mature human milk among five different groups: mothers of normal spontaneous delivery-term (NS-T), caesarean delivery-term (CS-T), premature (PT), small for gestational age (SGA), and large for gestational age (LGA) infants. Fungi were detected in 80 out of the 88 samples. Regarding the number of observed fungal species, the NS-T group was more homogeneous (less variable) comparing the other groups (P<0.05). In the transient human milk samples, the most abundant species were Saccharomyces cerevisiae (33.3%) and Aspergillus glaucus (27.4%). While A. glaucus (33.7%) was second most abundant species in mature milk, S. cerevisiae disappeared (P<0.01) and Penicillium rubens became the most abundant species (35.5%) (P<0.05). Among the NS-T group, the most abundant species was Malassezia globosa in both transient and mature milk. In contrast, S. cerevisiae was the most abundant species in transient human milk (45.0%) in the CS-T group, but it disappeared in mature milk (P<0.01). In transient milk, M. globosa was only represented 6.0-9.0% of taxa in the PT, SGA, and LGA groups (P<0.05). In transient and mature milk in the PT, SGA and LGA groups, the most abundant species were A. glaucus and P. rubens. In mature milk samples, P. rubens is more abundant in CS-T group, PT group and LGA group, than the NS-T groups (P<0.05 for all). Although fungi constitute only a very small part of the human milk microbiome, we observed some changes that the human milk mycobiota composition varies in caesarean delivery, premature, SGA and LGA groups, comparing the normal spontaneous delivery, as well as differences between transient and mature human milk.

Analysis of the gut microbiota in alopecia areata: identification of bacterial biomarkers

BACKGROUND

Alopecia areata is a T-cell-mediated autoimmune disease with an unknown etiopathogenesis. Gut microbiota has been revealed as a key modulator of systemic immunity.

OBJECTIVE

To determine whether patients affected by alopecia universalis present differences in gut bacteria composition compared with healthy controls and investigate possible bacterial biomarkers of the disease.

METHODS

We conducted a cross-sectional study that involved 15 patients affected by alopecia universalis and 15 controls. Gut microbiome of the study subjects was analysed by sequencing the 16SrRNA of stool samples. We searched for bacterial biomarkers of alopecia universalis using the linear discriminant analysis effect size (LEFse) tool.

RESULTS

In total, 30 study subjects (46.6% female; mean [SD] age, 40.1 [9.8] years) were enrolled. Neither alpha (Shannon diversity index 5.31 ± 0.43 vs. 5.03 ± 0.43, P 0.1) or beta diversity (ADONIS P value: 0.35) of gut microbiota showed statistically significant differences between cases and controls. In patients affected with alopecia, we found an enriched presence (LDA SCORE > 2) of Holdemania filiformis, Erysipelotrichacea, Lachnospiraceae, Parabacteroides johnsonii, Clostridiales vadin BB60 group, Bacteroides eggerthii and Parabacteroides distasonis. A predictive model based on the number of bacterial counts of Parabacteroides distasonis and Clostridiales vadin BB60 group correctly predicted disease status in 80% of patients (AUC 0.804 (0.633-0.976), P 0.004).

CONCLUSION

Alopecia universalis does not seem to affect broadly gut microbiota structure. Bacterial biomarkers found associated with the disease (Holdemania filiformis, Erysipelotrichacea, Lachnospiraceae, Parabacteroides johnsonii, Eggerthellaceae, Clostridiales vadin BB60 group, Bacteroides eggerthii and Parabacteroides distasonis) should be further studied as they could be involved in its pathophysiology or be used as diagnostic tools.

P1597 15-year follow-up of regional right and left ventricular function after the Senning operation: a colour-Doppler myocardial imaging study

OnBehalf

Ana Moya, 1994

Introduction

Although the development of right ventricular (RV) dysfunction in patients who underwent an atrial switch procedure is a major concern, long-term follow-up data on the evolution of myocardial function over time, especially using deformation myocardial imaging, is still lacking.

Purpose

This study aimed (1) at evaluating regional (base-mid-apex) RV and left ventricular (LV) function using Colour-Doppler myocardial imaging over a 15-year follow-up period (longitudinal analysis) and (2) at comparing results with age- and gender-matched controls (cross-sectional analysis).

Methods

For the longitudinal analysis, we compared systolic and diastolic function between 2004 and 2019 in 10 Senning patients. For the cross-sectional analysis, we compared the subaortic RV (sRV) of Senning patients with the RV and LV of matched controls and the subpulmonary LV (spLV) of Senning patients with the LV of matched controls.

Results

The longitudinal analysis (2004-2019) of sRV function showed a significant decrease in peak systolic strain (-16.9 ± 7.1% vs -12.0 ± 4.0%; P = 0.045), peak systolic strain rate (-1.1 ± 0.3s-1 vs -0.8 ± 0.4s-1; P = 0.003) and peak early diastolic velocity (-2.0 ± 1.2 cm/s vs -1.0 ± 0.5 cm/s; P = 0.036) at the apex. spLV function showed a significant decrease in peak systolic velocity (mid: 5.6 ± 1.8 cm/s vs 3.7 ± 1.1 cm/s; P = 0.013 and apex: 5.0 ± 1.7 cm/s vs 2.1 ± 1.2 cm/s; P = 0.011) and peak systolic strain rate (mid: -1.7 ± 0.5s-1 vs -1.0 ± 0.4s-1; P = 0.048).

The cross-sectional analysis revealed significant lower values for peak systolic velocity, peak systolic strain rate, peak systolic strain at all myocardial regions of the sRV when compared to both LV and RV of matched controls (all P &lt; 0.05). Similarly, early and late diastolic velocity were lower when compared to controls (P &lt; 0.05). The spLV showed lower values for peak systolic velocity and peak systolic strain rate (mid and apex, P &lt; 0.05), but not for peak systolic strain when compared to the LV of matched controls.

Conclusion

Our study shows little change in systolic and diastolic sRV function over a 15-year period, except in the apical region. Interestingly, there was a decline of spLV systolic function which may be of clinical value. On the other hand, when compared to age- and gender-matched controls, both the sRV and spLV of Senning patients exhibit significantly decreased measurements of longitudinal systolic and diastolic function.

A giant exoplanet orbiting a very-low-mass star challenges planet formation models

Surveys have shown that super-Earth and Neptune-mass exoplanets are more frequent than gas giants around low-mass stars, as predicted by the core accretion theory of planet formation. We report the discovery of a giant planet around the very-low-mass star GJ 3512, as determined by optical and near-infrared radial-velocity observations. The planet has a minimum mass of 0.46 Jupiter masses, very high for such a small host star, and an eccentric 204-day orbit. Dynamical models show that the high eccentricity is most likely due to planet-planet interactions. We use simulations to demonstrate that the GJ 3512 planetary system challenges generally accepted formation theories, and that it puts constraints on the planet accretion and migration rates. Disk instabilities may be more efficient in forming planets than previously thought.

Online oxygen monitoring using integrated inkjet-printed sensors in a liver-on-a-chip system

The demand for real-time monitoring of cell functions and cell conditions has dramatically increased with the emergence of organ-on-a-chip (OOC) systems. However, the incorporation of co-cultures and microfluidic channels in OOC systems increases their biological complexity and therefore makes the analysis and monitoring of analytical parameters inside the device more difficult. In this work, we present an approach to integrate multiple sensors in an extremely thin, porous and delicate membrane inside a liver-on-a-chip device. Specifically, three electrochemical dissolved oxygen (DO) sensors were inkjet-printed along the microfluidic channel allowing local online monitoring of oxygen concentrations. This approach demonstrates the existence of an oxygen gradient up to 17.5% for rat hepatocytes and 32.5% for human hepatocytes along the bottom channel. Such gradients are considered crucial for the appearance of zonation of the liver. Inkjet printing (IJP) was the selected technology as it allows drop on demand material deposition compatible with delicate substrates, as used in this study, which cannot withstand temperatures higher than 130 °C. For the deposition of uniform gold and silver conductive inks on the porous membrane, a primer layer using SU-8 dielectric material was used to seal the porosity of the membrane at defined areas, with the aim of building a uniform sensor device. As a proof-of-concept, experiments with cell cultures of primary human and rat hepatocytes were performed, and oxygen consumption rate was stimulated with carbonyl-cyanide-4-(trifluoromethoxy)phenylhydrazone (FCCP), accelerating the basal respiration of 0.23 ± 0.07 nmol s-1/106 cells up to 5.95 ± 0.67 nmol s-1/106 cells s for rat cells and the basal respiration of 0.17 ± 0.10 nmol s-1/106 cells by up to 10.62 ± 1.15 nmol s-1/106 cells for human cells, with higher oxygen consumption of the cells seeded at the outflow zone. These results demonstrate that the approach of printing sensors inside an OOC has tremendous potential because IJP is a feasible technique for the integration of different sensors for evaluating metabolic activity of cells, and overcomes one of the major challenges still remaining on how to tap the full potential of OOC systems.

The effects of prebiotics on microbial dysbiosis, butyrate production and immunity in HIV-infected subjects

Altered interactions between the gut mucosa and bacteria during HIV infection seem to contribute to chronic immune dysfunction. A deeper understanding of how nutritional interventions could ameliorate gut dysbiosis is needed. Forty-four subjects, including 12 HIV⁺ viremic untreated (VU) patients, 23 antiretroviral therapy-treated (ART⁺) virally suppressed patients (15 immunological responders and 8 non-responders) and 9 HIV^- controls (HIV^-), were blindly randomized to receive either prebiotics (scGOS/lcFOS/glutamine) or placebo (34/10) over 6 weeks in this pilot study. We assessed fecal microbiota composition using deep 16S rRNA gene sequencing and several immunological and genetic markers involved in HIV immunopathogenesis. The short dietary supplementation attenuated HIV-associated dysbiosis, which was most apparent in VU individuals but less so in ART⁺ subjects, whose gut microbiota was found more resilient. This compositional shift was not observed in the placebo arm. Significantly, declines in indirect markers of bacterial translocation and T-cell activation, improvement of thymic output, and changes in butyrate production were observed. Increases in the abundance of Faecalibacterium and Lachnospira strongly correlated with moderate but significant increases of butyrate production and amelioration of the inflammatory biomarkers soluble CD14 and high-sensitivity C-reactive protein, especially among VU. Hence, the bacterial butyrate synthesis pathway holds promise as a viable target for interventions.

External prolonged electrocardiogram monitoring in unexplained syncope and palpitations: results of the SYNARR-Flash study

AIMS

SYNARR-Flash study (Monitoring of SYNcopes and/or sustained palpitations of suspected ARRhythmic origin) is an international, multicentre, observational, prospective trial designed to evaluate the role of external 4-week electrocardiogram (ECG) monitoring in clinical work-up of unexplained syncope and/or sustained palpitations of suspected arrhythmic origin.

METHODS AND RESULTS

Consecutive patients were enrolled within 1 month after unexplained syncope or palpitations (index event) after being discharged from emergency room or hospitalization without a conclusive diagnosis. A 4-week ECG monitoring was obtained by external high-capacity loop recorder (SpiderFlash-T(®), Sorin) storing patient-activated and auto-triggered tracings. Diagnostic monitorings included (i) conclusive events with reoccurrence of syncope or palpitation with concomitant ECG recording (with/without arrhythmias) and (ii) events with asymptomatic predefined significant arrhythmias (sustained supraventricular or ventricular tachycardia, advanced atrio-ventricular block, sinus bradycardia <30 b.p.m., pauses >6 s). SYNARR-Flash study enrolled 395 patients (57.7% females, 56.9 ± 18.7 years, 28.1% with syncope, and 71.9% with palpitations) from 10 European centres. For syncope, the 4-week diagnostic yield was 24.5%, and predictors of diagnostic events were early start of recording (0-15 vs. >15 days after index event) (OR 6.2, 95% CI 1.3-29.6, P = 0.021) and previous history of supraventricular arrhythmias (OR 3.6, 95% CI 1.4-9.7, P = 0.018). For palpitations, the 4-week diagnostic yield was 71.6% and predictors of diagnostic events were history of recurrent palpitations (P < 0.001) and early start of recording (P = 0.001).

CONCLUSION

The 4-week external ECG monitoring can be considered as first-line tool in the diagnostic work-up of syncope and palpitation. Early recorder use, history of supraventricular arrhythmia, and frequent previous events increased the likelihood of diagnostic events during the 4-week external ECG monitoring.

Altered metabolism of gut microbiota contributes to chronic immune activation in HIV-infected individuals

Altered interplay between gut mucosa and microbiota during treated HIV infection may possibly contribute to increased bacterial translocation and chronic immune activation, both of which are predictors of morbidity and mortality. Although a dysbiotic gut microbiota has recently been reported in HIV+ individuals, the metagenome gene pool associated with HIV infection remains unknown. The aim of this study is to characterize the functional gene content of gut microbiota in HIV+ patients and to define the metabolic pathways of this bacterial community, which is potentially associated with immune dysfunction. We determined systemic markers of innate and adaptive immunity in a cohort of HIV-infected individuals on successful antiretroviral therapy without comorbidities and in healthy non-HIV-infected subjects. Metagenome sequencing revealed an altered functional profile, with enrichment of the genes involved in various pathogenic processes, lipopolysaccharide biosynthesis, bacterial translocation, and other inflammatory pathways. In contrast, we observed depletion of genes involved in amino acid metabolism and energy processes. Bayesian networks showed significant interactions between the bacterial community, their altered metabolic pathways, and systemic markers of immune dysfunction. This study reveals altered metabolic activity of microbiota and provides novel insight into the potential host-microbiota interactions driving the sustained inflammatory state in successfully treated HIV-infected patients.

Influenza vaccine: Delayed vaccination schedules and missed opportunities in children under 2 years old

INTRODUCTION

In Argentina respiratory disease is the third leading cause of death in children under 5 years. In 2011 influenza vaccination was included in the National Calendar for children between 6 and 24 months (two doses schedule). Influenza vaccine coverage for second dose was 46.1% in 2013. The aim was to determine the proportion of delayed schedules and missed opportunities, to assess the characteristics of missed opportunities for vaccination and to explore the perception of influenza disease and vaccination from the parents of children between 6 and 24 months in different regions of Argentina in 2013.

METHODS

Analytical observational multicenter cross-sectional study. Structured surveys were carried out to the children's parents who were between 6 and 24 months of age during the influenza virus vaccination season (April-October 2013). Chi-Square test was used to assess association and differences between proportions and categorical variables. A logistic regression model was built to identify delay predictor variables in the vaccination schedules. Missed opportunities for vaccination were characterized through the estimation of proportions.

RESULTS

1350 surveys were conducted in the three centers. We detected 65% (884/1340) of delayed influenza vaccination schedules, 97% of them associated with missed opportunities of vaccination. The independent protective factors associated with a decreases risk of delayed schedules were: (a) perception of the importance of influenza vaccination (OR=0.42(0.18-0.94); p=0.035), (b) having less than one year of age (OR=0.75(0.59-0.96); p=0.022), (c) to have received information in pediatric visits or in any media (OR=0.71(0.56-0.90); p=0.004). There was 38% of MOIV in 1st dose and 63.4% in 2nd dose. The main cause of MOIV in 1st dose was not detecting the need for vaccination (39%) and in 2nd dose the unknowledge of the vaccination schedule (35.3%). No cultural reasons were detected.

CONCLUSIONS

High frequency of delayed vaccination schedules and missed opportunities were detected. Parents had little concern about the safety of influenza vaccine.

Simultaneous monitoring of Staphylococcus aureus growth in a multi-parametric microfluidic platform using microscopy and impedance spectroscopy

We describe the design, construction, and characterization of a scalable microfluidic platform that allows continuous monitoring of biofilm proliferation under shear stress conditions. Compared to other previous end-point assay studies, our platform offers the advantages of integration into multiple environments allowing simultaneous optical microscopy and impedance spectroscopy measurements. In this work we report a multi-parametric sensor that can monitor the growth and activity of a biofilm. This was possible by combining two interdigitated microelectrodes (IDuEs), and punctual electrodes to measure dissolved oxygen, K+, Na+ and pH. The IDuE has been optimized to permit sensitive and reliable impedance monitoring of Staphylococcus aureus V329 growth with two- and four-electrode measurements. We distinguished structural and morphological changes on intact cellular specimens using four-electrode data modeling. We also detected antibiotic mediated effects using impedance. Results were confirmed by scanning electrode microscopy and fluorescence microscopy after live/dead cell staining. The bacitracin mediated effects detected with impedance prove that the approach described can be used for guiding the development of novel anti-biofilm agents to better address bacterial infection.

Retrospective case-control study of viral pathogen screening in proliferative verrucous leukoplakia lesions

OBJECTIVE

This study aimed to survey the presence of known oncoviruses in oral biopsies from patients diagnosed with the aetiologically undetermined proliferative verrucous leukoplakia and compare results to those from milder oral leukoplakia (OL) cases, oral squamous cell carcinoma, a common outcome of the lesions of interest, and healthy controls.

DESIGN

Blind, retrospective, case-control study.

SETTING

A stomatology unit in an academic Hospital and a Public Health laboratory.

PARTICIPANTS

Forty patients were divided in four groups. Ten patients had been diagnosed with proliferative verrucous leukoplakia, 10 with OL and 10 with OSCC, and 10 were healthy subjects.

MAIN OUTCOME MEASURES

The presence or absence of oncovirus DNA was assayed with the amplification of viral genetic markers using PCR and subsequent gel electrophoresis confirmation. Amplified fragments were sequenced and identified bioinformatically.

RESULTS

No DNA from the herpesvirus, papillomavirus or polyomavirus species was detected in the samples.

CONCLUSIONS

No association between proliferative verrucous leukoplakia and target viruses was detected. A higher throughput viral metagenomic approach may prove valuable for future analyses, as it would not be restricted to a priori knowledge of potential targets.

Bronchial microbiome of severe COPD patients colonised by Pseudomonas aeruginosa

The bronchial microbiome in severe COPD during stability and exacerbation in patients chronically colonised by Pseudomonas aeruginosa (PA), has not been defined. Our objective was to determine the characteristics of the bronchial microbiome of severe COPD patients colonised and not colonised by P. aeruginosa and its changes during exacerbation. COPD patients with severe disease and frequent exacerbations were categorised according to chronic colonisation by P. aeruginosa. Sputum samples were obtained in stability and exacerbation, cultured, and analysed by 16S rRNA gene amplification and pyrosequencing. Sixteen patients were included, 5 of them showing chronic colonisation by P. aeruginosa. Pseudomonas genus had significantly higher relative abundance in stable colonised patients (p = 0.019), but no significant differences in biodiversity parameters were found between the two groups (Shannon, 3 (2-4) vs 3 (2-3), p = 0.699; Chao1, 124 (77-159) vs 140 (115-163), p = 0.364). In PA-colonised patients bronchial microbiome changed to a microbiome similar to non-PA-colonised patients during exacerbations. An increase in the relative abundance over 20 % during exacerbation was found for Streptococcus, Pseudomonas, Moraxella, Haemophilus, Neisseria, Achromobacter and Corynebacterium genera, which include recognised potentially pathogenic microorganisms, in 13 patients colonised and not colonised by P. aeruginosa with paired samples. These increases were not identified by culture in 5 out of 13 participants (38.5 %). Stable COPD patients with severe disease and PA-colonised showed a similar biodiversity to non-PA-colonised patients, with a higher relative abundance of Pseudomonas genus in bronchial secretions. Exacerbation in severe COPD patients showed the same microbial pattern, independently of previous colonisation by P. aeruginosa.

Meconium microbiota types dominated by lactic acid or enteric bacteria are differentially associated with maternal eczema and respiratory problems in infants

BACKGROUND

Culture-dependent methods have shown that meconium, the newborn's first intestinal discharge, is not sterile, but the diversity of bacteria present in this material needs to be further characterized by means of more sensitive molecular techniques.

OBJECTIVE

Our aims were to characterize molecularly the meconium microbiota in term infants, to assess whether it contributes to the future microbiota of the infants' gastrointestinal tract, and to evaluate how it relates to lifestyle variables and atopy-related conditions.

METHODS

We applied high-throughput pyrosequencing of the 16S rRNA gene to study the meconium microbiota in twenty term newborns from a Spanish birth cohort. For comparison, we characterized the microbiota in fecal samples from seven pregnant women days before delivery and in two series of infant samples spanning the first seven months of life. We also compared our data with vaginal and skin microbiota characterized in independent studies. Different types of meconium microbiota were defined based on taxonomic composition and abundance and their associations with different factors were statistically evaluated.

RESULTS

The meconium microbiota differs from those in adult feces, vagina and skin, but resembles that of fecal samples from young infants. Meconium samples clustered into two types with different bacterial diversity, richness and composition. One of the types was less diverse, dominated by enteric bacteria and associated with a history of atopic eczema in the mother (P = 0.038), whereas the second type was dominated by lactic acid bacteria and associated with respiratory problems in the infant (P = 0.040).

CONCLUSIONS & CLINICAL RELEVANCE

Our findings suggest that the meconium microbiota has an intrauterine origin and participates in gut colonization. Although based on a small population sample, our association analyses also suggest that the type of bacteria detected in meconium is influenced by maternal factors and may have consequences for childhood health.

Metagenomics of human microbiome: beyond 16s rDNA

The gut microbiota presents a symbiotic relationship with the human host playing a beneficial role in human health. Since its establishment, the bacterial community is subjected to the influence of many different factors that shape its composition within each individual. However, an important convergence is observed at functional level in the gut microbiota. A metatranscriptomic study of healthy individuals showed homogeneity in the composition of the active microbiota that increased further at functional level.

Urinary leukotriene excretion profile in children with exercise-induced asthma compared with controls: a preliminary study

BACKGROUND

Leukotrienes are among the most important mediators associated with inflammatory responses in patients with exercise induced asthma (EIA). The aim of this study was to investigate the impact of exercise on the urinary leukotriene profile. Hence, we compared post exercise changes of urinary leukotriene E4 (LTE4) concentration between children with EIA and healthy controls.

METHODS

Ten children with EIA and 15 controls were enrolled. Both groups underwent a standardised exercise challenge test (ECT). LTE4 concentration was measured in urine samples obtained pre and post ECT, using enzyme immunoassay and adjusted by urinary creatinine concentrations.

RESULTS

Median (minimum-maximum) pre ECT concentration of LTE4 was 17.82 (7.58-90.23 pg/ml) in EIA and 17.24 (4.64-64.02 pg/ml) in controls, p=0.86. LTE4 concentration post ECT were 23.37 (4.02-93.00 pg/ml) in EIA and 11.74 (0.13-25.09 pg/ml) in controls, p=0.02. Changes of LTE4 concentration post ECT were 2.54 (-31.98 to 43.31 pg/ml) in cases and -13.53 (-46.00 to 11.02 pg/ml) in controls, p=0.03. There was no significant correlation between basal predicted FEV(1) [%] and changes in LTE4 concentration in cases (i.e., r(s)=0.14) nor controls (i.e., r(s)=0.12). There was a tendency towards more pronounced changes in LTE4 concentration post ECT in children with moderate/mild persistent asthma compared to those with mild but intermittent asthma.

CONCLUSIONS

Children with EIA had significantly higher changes of urinary LTE4 concentrations post ECT compared to healthy controls. Urinary measurement of LTE4 may be an interesting and non-invasive option to assess control of EIA in children.

The transcriptomic response to thermal stress is immediate, transient and potentiated by ultraviolet radiation in the sea anemone Anemonia viridis

Among the environmental threats to coral reef health, temperature and ultraviolet increases have been proposed as major agents, although the relative contribution of each in the cnidarian/zooxanthellae symbiosis breakdown has been poorly addressed. We have investigated the transcriptomic response to thermal stress, with and without ultraviolet radiation (UVR), in the symbiotic sea anemone Anemonia viridis. Using the Oligo2K A. viridis microarray, dedicated to genes potentially involved in the symbiosis interaction, we monitored the gene expression profiles after 1, 2 and 5 days of stresses that further lead to massive losses of zooxanthellae. Each stress showed a specific gene expression profile with very little overlap. We showed that the major response to thermal stress is immediate (24 h) but returns to the baseline gene expression profile after 2 days. UVR alone has little effect but potentiates thermal stress, as a second response at 5 days was observed when the two stresses were coupled. Several pathways were highlighted, such as mesoglea loosening, cell death and calcium homeostasis and described in more details. Finally, we showed that the dermatopontin gene family, potentially involved in collagen fibrillogenesis, issued from actinarian-specific duplication events, with one member preferentially expressed in the gastroderm and specifically responding to stress. Anemonia viridis EST sequences have been deposited into GenBank dbEST ([GenBank:FK719875–FK759813].

Abdominal radiographic and ultrasonographic findings in ferrets (Mustela putorius furo) with systemic coronavirus infection

Ferret systemic coronavirus infection (FSCV) is a systemic disease in ferrets that clinically and pathologically resembles the dry form of FIP. The present study describes abdominal imaging features of 11 ferrets with FSCV. Abdominal survey radiographs were available for eight ferrets and ultrasound examination for all cases. Loss of lumbar musculature, decreased peritoneal detail, presence of mid-abdominal soft-tissue masses and splenomegaly were the most significant radiographic signs in these patients. Ultrasonographic findings including peritonitis, abdominal lymphadenopathy, splenomegaly, abdominal soft-tissue masses, nephromegaly and changes in the renal cortex echogenicity were recorded in the majority of cases with FSCV. As an imaging modality, ultrasound is superior to radiology when abdominal contrast is reduced, as it frequently occurs in these cases. However, although imaging techniques provide additional information in the antemortem diagnosis, they can not replace the definitive diagnosis based on histological and immunohistochemical results.

Pyogranulomatous pleuropneumonia and mediastinitis in ferrets (Mustela putorius furo) associated with Pseudomonas luteola Infection

Between 2008 and 2009, three pet ferrets from different sources presented with acute episode of dyspnoea. Cytological examination of pleural exudates revealed severe purulent inflammation with abundant clusters of rod-shaped microorganisms with a clear surrounding halo. Treatment was ineffective and the ferrets died 2–5 days later. Two ferrets were subjected to necropsy examination, which revealed pyothorax, mediastinal lymphadenopathy and multiple white nodules (1–2 mm) in the lungs. Microscopical examination showed multifocal necrotizing-pyogranulomatous pleuropneumonia and lymphadenitis with aggregates of encapsulated microorganisms, some of which were positively stained by periodic acid–Schiff and alcian blue. In-situ hybridization for Pneumocystis spp., Ziehl–Neelsen staining and immunohistochemistry for distemper, coronavirus and influenza antigen were negative in all cases. Electron microscopically, the bacteria were 2–3 μm long with a thick electron-lucent capsule. Microbiology from one ferret yielded a pure culture of gram-negative bacteria identified phenotypically as Pseudomonas luteola. This speciation was later confirmed by 16S RNA gene amplification.

Mitochondrial DNA effects on fitness in Drosophila subobscura

We tested different fitness components on a series of conspecific mtDNA haplotypes, detected by RFLPs in Drosophila subobscura. Additionally, haplotype VIII, endemic to the Canary Islands, was tested upon its own native nuclear DNA background and upon that of the rest of mtDNAs tested herein. We found that both nuclear and mitochondrial DNA can have a significant effect upon their hosts' fitness, and that negative selection is one of the mechanisms that can intervene in this species' mtDNA haplotype pattern. We discuss the importance of this mechanism in relation to genetic drift, in the form of periodic population bottlenecks, and how the latter can enhance the former. We also detected a significant positive effect of haplotype VIII upon fitness that could explain in part the dominance of this endemic haplotype on some of the Canary Islands, and a mitochondrial heterosis involving this haplotype when on a foreign nuclear DNA background.

Evolution of mitochondrial DNA in Drosophila subobscura

The colonization of the New World by the Palearctic species Drosophila subobscura was first detected in 1978 in South America and around 1982 in western North America. The ensuing dramatic expansion of the species, in territory as well as numbers, provides an opportunity for studying evolution in a scale rarely possible. We have used 10 restriction endonucleases to analyze the mitochondrial DNA (mtDNA) of individuals from 23 widely dispersed localities. Only two mtDNA composite morphs have been detected in the Americas. None of the two morphs has been found in Africa, and only one in the Atlantic islands; but both are widespread in Europe, which provides no clue of the precise geographic origin of the colonizers. The amount of nucleotide-substitution polymorphism detected in D. subobscura is typical for animals, but it is greater in the Old than in the New World, presumably due to the recent colonization by a limited number of colonizers. Assuming standard evolutionary rates of mtDNA base substitution, the mtDNA morphs found in D. subobscura can be traced to a single one that existed no less than one million years ago. We argue against the inference that the D. subobscura flies now living descend from only one or a few females that lived at that time. This type of inference, which we call the "Mother Eve hypothesis," has been made to conclude that the human population went through a severe constriction about 200,000 years ago, so that all living humans descend from only one or a few women who lived at that time. The Mother Eve hypothesis is fallacious.