Circulating Plasma miRNA Homologs in Mice and Humans Reflect Familial Cerebral Cavernous Malformation Disease

Patients with familial cerebral cavernous malformation (CCM) inherit germline loss of function mutations and are susceptible to progressive development of brain lesions and neurological sequelae during their lifetime. To date, no homologous circulating molecules have been identified that can reflect the presence of germ line pathogenetic CCM mutations, either in animal models or patients. We hypothesize that homologous differentially expressed (DE) plasma miRNAs can reflect the CCM germline mutation in preclinical murine models and patients. Herein, homologous DE plasma miRNAs with mechanistic putative gene targets within the transcriptome of preclinical and human CCM lesions were identified. Several of these gene targets were additionally found to be associated with CCM-enriched pathways identified using the Kyoto Encyclopedia of Genes and Genomes. DE miRNAs were also identified in familial-CCM patients who developed new brain lesions within the year following blood sample collection. The miRNome results were then validated in an independent cohort of human subjects with real-time-qPCR quantification, a technique facilitating plasma assays. Finally, a Bayesian-informed machine learning approach showed that a combination of plasma levels of miRNAs and circulating proteins improves the association with familial-CCM disease in human subjects to 95% accuracy. These findings act as an important proof of concept for the future development of translatable circulating biomarkers to be tested in preclinical studies and human trials aimed at monitoring and restoring gene function in CCM and other diseases.

Defining in Detail and Evaluating Reliability of DSM-5 Criteria for Autism Spectrum Disorder (ASD) Among Children

This paper describes a process to define a comprehensive list of exemplars for seven core Diagnostic and Statistical Manual (DSM) diagnostic criteria for autism spectrum disorder (ASD), and report on interrater reliability in applying these exemplars to determine ASD case classification. Clinicians completed an iterative process to map specific exemplars from the CDC Autism and Developmental Disabilities Monitoring (ADDM) Network criteria for ASD surveillance, DSM-5 text, and diagnostic assessments to each of the core DSM-5 ASD criteria. Clinicians applied the diagnostic exemplars to child behavioral descriptions in existing evaluation records to establish initial reliability standards and then for blinded clinician review in one site (phase 1) and for two ADDM Network surveillance years (phase 2). Interrater reliability for each of the DSM-5 diagnostic categories and overall ASD classification was high (defined as very good .60-.79 to excellent ≥ .80 Kappa values) across sex, race/ethnicity, and cognitive levels for both phases. Classification of DSM-5 ASD by mapping specific exemplars from evaluation records by a diverse group of clinician raters is feasible and reliable. This framework provides confidence in the consistency of prevalence classifications of ASD and may be further applied to improve consistency of ASD diagnoses in clinical settings.

Abstract P46: Baseline Characteristics of Patients With Cerebral Cavernous Angiomas With Symptomatic Hemorrhage in a Multisite Trial Readiness Study

Background: Patients with cerebral cavernous angiomas with symptomatic hemorrhage (CASH) have high risk of disability from recurrent bleeding. Candidate medications to prevent rebleeding in CASH lesions will require multisite clinical trials with standardized data collection.

Objective: To report the prevalence and baseline cohort features in CASH patients and establish a research network infrastructure for trials.

Methods: This prospective observational cohort study includes adults with radiologically verified CASH lesion within 1-year of consent. Exclusions include prior or planned surgical intervention, spinal location, or prior brain irradiation. Six sites enrolled patients into the screening and clinical assessment portion of the study starting July 2018. Patients also had the option to participate in the follow up biomarker validation at 4 sites. Baseline demographics, clinical and imaging information, and outcomes (mRS, PROMIS-29, NIHSS, and EuroQol-5D) were collected. Biomarker imaging included dynamic contrast enhanced quantitative perfusion (DCEQP) and quantitative susceptibility mapping (QSM) that correlated with symptomatic bleeding. Descriptive statistics were performed and one-sample t-test was used to compare whether mean T-scores for PROMIS-29 domains differed significantly from a reference population.

Results: As of May 2020, 849 CASH patients were screened of whom 110 (13%) were eligible and enrolled; 73 also enrolled into the biomarker validation study. Average age at enrollment was 46±16 years at a mean of 4.4 months after symptom onset; 53% were female, 41% were familial, and 43% of CASH lesions were brainstem location. At enrollment, 90% of the cohort had independent functional outcome (mRS ≤ 2 and NIHSS <5). Perceived health problems affecting QoL were reported in >30% (EuroQol-5D). CASH cases had significantly worse anxiety but better depression and social satisfaction scores compared to a general population (all P<0.01). Baseline DCEQP and QSM measures did not differ significantly across sites.

Conclusion: We demonstrate feasibility of multisite recruitment of CASH patients and report prevalence of baseline features that will aid in design of clinical trials and inclusion of appropriate outcome measures.

Abstract P737: Human Homologs Of Differentially Expressed Plasma MicroRNAs In Preclinical Murine Models Target Fundamental Mechanisms Of Cerebral Cavernous Malformation

Introduction: There is a current need for sensitive and specific biomarkers of Cerebral Cavernous Malformation (CCM) that can be readily translated from preclinical to human models to accurately diagnose and monitor disease states and response to novel therapeutics. MiRNAs are small non-coding RNAs that influence gene expression and whose levels can be affected by disease states. We hypothesize that there are human homologs of differentially expressed (DE) miRNA in the plasma of CCM murine models that can be identified in CCM patients. We further hypothesize that these miRNAs have gene targets within previously published CCM transcriptomes, mechanistically linking them to CCM disease.

Methods: Plasma miRNAs from homozygous and heterozygous Ccm1 and Ccm3 mice, as well as their respective wild type controls were sequenced and analyzed. Putative gene targets of DE miRNAs [p<0.05, false discovery rate (FDR) corrected] were queried in previously published mouse CCM transcriptomes. The human homologs of the DE miRNAs in the plasma of Ccm1 and Ccm3 mouse models were identified and assessed in the plasma of healthy controls (n=13), CCM1 (n=11), and CCM3 (n=11) patients using RT-qPCR.

Results: 5 miRNAs in homozygous and 10 in heterozygous for Ccm1 , while 45 in homozygous and 2 in heterozygous for Ccm3 were DE in the plasma of mouse models (p<0.05, FDR corrected), had gene targets within CCM mouse transcriptomes, and have a human homolog. Preliminary results show mmu-miR-375-3p as DE in both Ccm1 +/- and Ccm3 -/- mice. RT-qPCR assays show that plasma relative quantification values of the human homolog hsa-miR-375-3p were higher in CCM3 than in CCM1 patients ( p <0.001) and in healthy controls ( p <0.05).

Conclusion: DE plasma miRNAs identified in mouse models with human homologs and putative gene targets mechanistically implicated in CCM disease may be used as candidate biomarkers for specific clinical contexts.

Common transcriptome, plasma molecules, and imaging signatures in the aging brain and a Mendelian neurovascular disease, cerebral cavernous malformation

Brain senescence is associated with impaired endothelial barrier function, angiogenic and inflammatory activity, and propensity to brain hemorrhage. The same pathological changes occur in cerebral cavernous malformations (CCM), a genetic neurovascular anomaly. We hypothesized common transcriptomic and plasma cytokine signatures in the aging brain and CCM. We identified 320 genes [fold change ≥1.5; p < 0.05; false discovery rate (FDR) corrected] commonly dysregulated in the aging brain and CCM. Ontology and pathway analyses of the common differentially expressed genes were related to inflammation and extracellular matrix organization. Plasma levels of C-reactive protein and angiopoietin-2 were significantly greater in older compared to younger healthy non-CCM subjects and were also greater in CCM (Sporadic and Familial) subjects regardless of age (all: p < 0.05; FDR corrected). Plasma levels of vascular endothelial growth factor were significantly greater in older compared to younger subjects, in both healthy non-CCM and Sporadic-CCM groups (all: p_adj < 0.05). Plasma levels of vascular endothelial growth factor were also significantly greater in Familial-CCM cases with germ line mutations regardless of age (all: p_adj < 0.05) compared to both healthy non-CCM and Sporadic-CCM subjects. Brain white matter vascular permeability assessed by MRI followed the same pattern as vascular endothelial growth factor across all groups. In addition, quantitative susceptibility mapping of brain white matter, a measure of iron deposition, was increased in older compared to younger healthy non-CCM subjects. Genetic aberrations, plasma molecules, and imaging biomarkers in a well characterized Mendelian neurovascular disease may also be applicable in the aging brain. Graphical abstract.

Development and validation of study filters for identifying controlled non-randomized studies in PubMed and Ovid MEDLINE

A retrospective analysis published by the German Institute for Quality and Efficiency in Health Care (IQWiG) in 2018 concluded that no filter for non-randomized studies (NRS) achieved sufficient sensitivity (≥92%), a precondition for comprehensive information retrieval. New NRS filters are therefore required, taking into account the challenges related to this study type. Our evaluation focused on the development of study filters for NRS with a control group ("controlled NRS"), as this study type allows the calculation of an effect size. In addition, we assumed that due to the more explicit search syntax, controlled NRS are easier to identify than non-controlled ones, potentially resulting in better performance measures of study filters for controlled NRS. Our aim was to develop study filters for identifying controlled NRS in PubMed and Ovid MEDLINE. We developed two new search filters that can assist clinicians and researchers in identifying controlled NRS in PubMed and Ovid MEDLINE. The reference set was based on 2110 publications in Medline extracted from 271 Cochrane reviews and on 4333 irrelevant references. The first filter maximizes sensitivity (92.42%; specificity 79.67%, precision 68.49%) and should be used when a comprehensive search is needed. The second filter maximizes specificity (92.06%; precision 82.98%, sensitivity 80.94%) and should be used when a more focused search is sufficient.

Phenotypic characterization of murine models of cerebral cavernous malformations

Cerebral cavernous malformations (CCMs) are clusters of dilated capillaries that affect around 0.5% of the population. CCMs exist in two forms, sporadic and familial. Mutations in three documented genes, KRIT1(CCM1), CCM2, and PDCD10(CCM3), cause the autosomal dominant form of the disease, and somatic mutations in these same genes underlie lesion development in the brain. Murine models with constitutive or induced loss of respective genes have been applied to study disease pathobiology and therapeutic manipulations. We aimed to analyze the phenotypic characteristic of two main groups of models, the chronic heterozygous models with sensitizers promoting genetic instability, and the acute neonatal induced homozygous knockout model. Acute model mice harbored a higher lesion burden than chronic models, more localized in the hindbrain, and largely lacking iron deposition and inflammatory cell infiltrate. The chronic model mice showed a lower lesion burden localized throughout the brain, with significantly greater perilesional iron deposition, immune B- and T-cell infiltration, and less frequent junctional protein immunopositive endothelial cells. Lesional endothelial cells in both models expressed similar phosphorylated myosin light chain immunopositivity indicating Rho-associated protein kinase activity. These data suggest that acute models are better suited to study the initial formation of the lesion, while the chronic models better reflect lesion maturation, hemorrhage, and inflammatory response, relevant pathobiologic features of the human disease.

Abstract TP582: A Multi-Site Validation of MRI Biomarkers of Vascular Leak and Hemorrhage for Forthcoming Clinical Trials

Background: Cerebral cavernous malformation is a genetic neurovascular disorder causing aberrant angiogenesis and lesion development within capillary beds. Lesions exhibit impaired endothelial barrier function, causing blood-brain barrier leakage and hemorrhage. Quantitative MRI biomarkers (dynamic contrast-enhanced quantitative permeability (DCEQP) and quantitative susceptibility mapping (QSM)) have been shown to correlate with CCM disease progression as measures of barrier leakage and hemorrhagic iron deposition, and there is interest in utilizing these biomarkers as endpoints in clinical trials. However, their consistencies across multiple platforms and institutions has not yet been rigorously verified.

Materials and Methods: Instruments used were a 3T Philips Ingenia at University of Chicago and a 3T Siemens Prisma at Northwestern University. QSM was assessed by five balloons filled with varying concentrations of MultiHance, corresponding to magnetic susceptibilities of 0, 0.1, 0.2, 0.4, and 0.8, surrounded by an agarose gel. Permeability was assessed by the injection of a bolus of MultiHance through a coiled hose inside a water-filled shell, and the consistency of the peak-to-peak ratio of the curves at the input and output was measured. Each biomarker was assessed by accuracy (to expected values, Pearson correlation), precision (between repeated measurements, paired t-test), and reproducibility (between instruments, paired t-test).

Results: QSM measured with an accuracy of r 2 = 0.997 on the Philips Achieva and r 2 = 0.999 on the Siemens Prisma. Each scanner had adequate precision between measurements, showing no significant difference by a paired t-test (p = 0.66 Achieva, p = 0.45 Prisma), and the reproducibility between scanners also showed no significant difference (p = 0.89). The peak-to-peak ratio on DCEQP scans was accurate (r 2 = 0.998), precise between measurements (p = 0.54), and repeatable between instruments (p = 0.49).

Conclusion: Quantitative imaging biomarkers DCEQP and QSM are accurate, consistent across multiple measurements, and between platforms and will be useful for future clinical trials in CCM.

Micro-computed tomography in murine models of cerebral cavernous malformations as a paradigm for brain disease

BACKGROUND

Cerebral cavernous malformations (CCMs) are hemorrhagic brain lesions, where murine models allow major mechanistic discoveries, ushering genetic manipulations and preclinical assessment of therapies. Histology for lesion counting and morphometry is essential yet tedious and time consuming. We herein describe the application and validations of X-ray micro-computed tomography (micro-CT), a non-destructive technique allowing three-dimensional CCM lesion count and volumetric measurements, in transgenic murine brains.

NEW METHOD

We hereby describe a new contrast soaking technique not previously applied to murine models of CCM disease. Volumetric segmentation and image processing paradigm allowed for histologic correlations and quantitative validations not previously reported with the micro-CT technique in brain vascular disease.

RESULTS

Twenty-two hyper-dense areas on micro-CT images, identified as CCM lesions, were matched by histology. The inter-rater reliability analysis showed strong consistency in the CCM lesion identification and staging (K=0.89, p<0.0001) between the two techniques. Micro-CT revealed a 29% greater CCM lesion detection efficiency, and 80% improved time efficiency.

COMPARISON WITH EXISTING METHOD

Serial integrated lesional area by histology showed a strong positive correlation with micro-CT estimated volume (r(2)=0.84, p<0.0001).

CONCLUSIONS

Micro-CT allows high throughput assessment of lesion count and volume in pre-clinical murine models of CCM. This approach complements histology with improved accuracy and efficiency, and can be applied for lesion burden assessment in other brain diseases.

Ureaplasma diversum in bull semen in Australia: its detection and potential effects

BACKGROUND

The primary objective of this study was to confirm the infection status of Ureaplasma diversum in Australian bulls and to identify morphological changes of sperm from U. diversum-positive bulls.

METHODS

Fresh semen samples were taken from 29 sexually active beef bulls from suspect herds in the Riverina/Upper Murray region. U. diversum was identified using PCR analyses and culture of the organism.

RESULTS

Nine of the bulls were PCR-positive for U. diversum but none of these had genital lesions. Sperm from infected bulls showed increased incidence of abnormal tails (bent and coiled), as well as surface abnormalities (i.e. small protuberances or lumps).

CONCLUSIONS

The results suggest impairment of sperm function and possibly fertility. Further investigations into the potential role of U. diversum as a pathogen for Australian cattle are warranted.

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

AIMS

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

METHODS AND RESULTS

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

CONCLUSION

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

Softening of cattle hoof soles and swelling of heel horn by environmental agents

Bovine soles and shavings from the heel were used in laboratory tests that examined the softening and swelling effects of rainwater, cow slurry (faeces plus urine), urine, silage effluent, and washings from recently laid concrete. Formalin, glutaraldehyde and butyraldehyde were compared for their ability to prevent softening induced by water, urine or urea plus 2-mercaptoethanol. Exposure to rainwater, slurry or urine for 72 h softened the soles on average by 16, 13 and 14 Shore Durometer Units. Silage effluent had less softening effect on soles (7 Shore Durometer Units), and pre-treating heel shavings with silage effluent reversed the swelling effect of water. Washings and scrapings taken from 3- and 7-d-old concrete surfaces prepared from Portland cement, caused swelling in heel shavings by a factor of 1.5 and 1.3. Formaldehyde, glutaraldehyde and butyraldehyde pre-treatment reduced the sole softening effect of urea plus 2-mercaptoethanol in cow soles. Formaldehyde and glutaraldehyde pre-treatment reduced the sole softening effect of urine, and formaldehyde was effective at reducing concrete washings-induced swelling. The findings are relevant to solar bruising and ulceration in cattle.

Irritable bowel syndrome: relationship of disorders in the transit of a single solid meal to symptom patterns

The time taken for a solid meal to pass through the stomach, small intestine, and colon was measured in 61 patients with irritable bowel syndrome, subdivided according to their presenting symptoms, and in 53 healthy volunteers. Small bowel transit times were significantly shorter in patients who complained predominantly of diarrhoea (3.3 +/- 0.3 vs 4.2 +/- 0.2 h; p = 0.01; n = 21) and significantly longer in patients who complained predominantly of constipation (5.4 +/- 0.3 vs 4.2 +/- 0.2 h; p less than 0.01; n = 23) or pain and distension (5.4 +/- 0.4 vs 4.2 +/- 0.2 h; p less than 0.01; n = 17) compared with controls. Whole gut transit times were shorter in patients who complained of diarrhoea (35 +/- 5 vs 53 +/- 4 h; p less than 0.01), and longer in patients with constipation (87 +/- 13 vs 53 +/- 4 h; p less than 0.05) compared with controls. No significant differences in gastric emptying rates were shown between any of the patient groups and normal controls. Thirty-four patients reported pain, particularly in the right iliac fossa, during the meal transit test, and in 25 of these (74%), the onset of the pain was associated with the arrival of residues of the test meal in the caecum. Our results indicate that irritable bowel syndrome should be considered a disease of the small intestine as well as the colon.

Electrochemical detector for breath hydrogen determination: measurement of small bowel transit time in normal subjects and patients with the irritable bowel syndrome

A method is described for the measurement of hydrogen in expired air, using an electrochemical detector. The apparatus is simple to use and sensitive. Its application is illustrated by studies of small bowel transit time made by measuring the time between oral ingestion of the unabsorbable carbohydrate lactulose and a rise in the concentration of hydrogen in expired air. In 20 control subjects transit time was 93.0 +/- 6.6 minutes, while in 16 patients with diarrhoea due to the irritable bowel syndrome it was 54.1 +/- 6.3 minutes (P less than 0.001), suggesting an abnormality in small intestinal motility in these patients. Loperamide, a potent antidiarrhoeal agent, increased transit time in 12 of these patients from 56.3 +/- 6.7 to 100.0 +/- 10.2 minutes (P less than 0.001).