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Abstract Background Both memory clinic professionals and patients see value in digital tools, yet these hardly find their way to clinical practice. We explored the usability of a digital tool to support the diagnostic work-up in daily memory clinic practice. We evaluated four modules that integrate multi-modal patient data (1.cognitive test; cCOG, and 2. MRI quantification; cMRI) into useful diagnostic information for clinicians (3. cDSI) and understandable and personalized information for patients (4. patient report). Methods We conducted a mixed-methods study in five Dutch memory clinics. Fourteen clinicians (11 geriatric specialists/residents, two neurologists, one nurse practitioner) were invited to integrate the tool into routine care with 43 new memory clinic patients. We evaluated usability and user experiences through quantitative data from questionnaires (patients, care partners, clinicians), enriched with thematically analyzed qualitative data from interviews (clinicians). Results We observed wide variation in tool use among clinicians. Our core findings were that clinicians: 1) were mainly positive about the patient report, since it contributes to patient-centered and personalized communication. This was endorsed by patients and care partners, who indicated that the patient report was useful and understandable and helped them to better understand their diagnosis, 2) considered the tool acceptable in addition to their own clinical competence, 3) indicated that the usefulness of the tool depended on the patient population and purpose of the diagnostic process, 4) addressed facilitators (ease of use, practice makes perfect) and barriers (high workload, lack of experience, data unavailability). Conclusion This multicenter usability study revealed a willingness to adopt a digital tool to support the diagnostic process in memory clinics. Clinicians, patients, and care partners appreciated the personalized diagnostic report. More attention to education and training of clinicians is needed to utilize the full functionality of the tool and foster implementation in actual daily practice. These findings provide an important step towards a lasting adoption of digital tools in memory clinic practice.

Abstract Background Angelman syndrome (AS) is a rare neurodevelopmental disorder characterized by severe intellectual disability, little to no expressive speech, visual and motor problems, emotional/behavioral challenges, and a tendency towards hyperphagia and weight gain. The characteristics of AS make it difficult to measure these children’s functioning with standard clinical tests. Feasible outcome measures are needed to measure current functioning and change over time, in clinical practice and clinical trials. Aim Our first aim is to assess the feasibility of several functional tests. We target domains of neurocognitive functioning and physical growth using the following measurement methods: eye-tracking, functional Near-Infrared Spectroscopy (fNIRS), indirect calorimetry, bio-impedance analysis (BIA), and BOD POD (air-displacement plethysmography). Our second aim is to explore the results of the above measures, in order to better understand the AS phenotype. Methods The study sample consisted of 28 children with AS aged 2–18 years. We defined an outcome measure as feasible when (1) at least 70% of participants successfully finished the measurement and (2) at least 60% of those participants had acceptable data quality. Adaptations to the test procedure and reasons for early termination were noted. Parents rated acceptability and importance and were invited to make recommendations to increase feasibility. The results of the measures were explored. Results Outcome measures obtained with eye-tracking and BOD POD met the definition of feasibility, while fNIRS, indirect calorimetry, and BIA did not. The most important reasons for early termination of measurements were showing signs of protest, inability to sit still and poor/no calibration (eye-tracking specific). Post-calibration was often applied to obtain valid eye-tracking results. Parents rated the BOD POD als most acceptable and fNIRS as least acceptable for their child. All outcome measures were rated to be important. Exploratory results indicated longer reaction times to high salient visual stimuli (eye-tracking) as well as high body fat percentage (BOD POD). Conclusions Eye-tracking and BOD POD are feasible measurement methods for children with AS. Eye-tracking was successfully used to assess visual orienting functions in the current study and (with some practical adaptations) can potentially be used to assess other outcomes as well. BOD POD was successfully used to examine body composition. Trial registration Registered d.d. 23-04-2020 under number ‘NL8550’ in the Dutch Trial Register: https://onderzoekmetmensen.nl/en/trial/23075

Abstract Background The paradigm shift towards earlier Alzheimer’s disease (AD) stages and personalized medicine creates new challenges for clinician-patient communication. We conducted a survey among European memory clinic professionals to identify opinions on communication about (etiological) diagnosis, prognosis, and prevention, and inventory needs for augmenting communication skills. Methods Memory clinic professionals (N = 160) from 21 European countries completed our online survey (59% female, 14 ± 10 years' experience, 73% working in an academic hospital). We inventoried (1) opinions on communication about (etiological) diagnosis, prognosis, and prevention using 11 statements; (2) current communication practices in response to five hypothetical cases (AD dementia, mild cognitive impairment (MCI), subjective cognitive decline (SCD), with ( +) or without ( −) abnormal AD biomarkers); and (3) needs for communication support regarding ten listed communication skills. Results The majority of professionals agreed that communication on diagnosis, prognosis, and prevention should be personalized to the individual patient. In response to the hypothetical patient cases, disease stage influenced the inclination to communicate an etiological AD diagnosis: 97% would explicitly mention the presence of AD to the patient with AD dementia, 68% would do so in MCI + , and 29% in SCD + . Furthermore, 58% would explicitly rule out AD in case of MCI − when talking to patients, and 69% in case of SCD − . Almost all professionals (79–99%) indicated discussing prognosis and prevention with all patients, of which a substantial part (48–86%) would personalize their communication to patients’ diagnostic test results (39–68%) or patients’ anamnestic information (33–82%). The majority of clinicians (79%) would like to use online tools, training, or both to support them in communicating with patients. Topics for which professionals desired support most were: stimulating patients’ understanding of information, and communicating uncertainty, dementia risk, remotely/online, and with patients not (fluently) speaking the language of the country of residence. Conclusions In a survey of European memory clinic professionals, we found a strong positive attitude towards communication with patients about (etiological) diagnosis, prognosis, and prevention, and personalization of communication to characteristics and needs of individual patients. In addition, professionals expressed a need for supporting tools and skills training to further improve their communication with patients.

BackgroundThe use of amyloid-PET in dementia workup is upcoming. At the same time, amyloid-PET is costly and limitedly available. While the appropriate use criteria (AUC) aim for optimal use of amyloid-PET, their limited sensitivity hinders the translation to clinical practice. Therefore, there is a need for tools that guide selection of patients for whom amyloid-PET has the most clinical utility. We aimed to develop a computerized decision support approach to select patients for amyloid-PET.MethodsWe included 286 subjects (135 controls, 108 Alzheimer's disease dementia, 33 frontotemporal lobe dementia, and 10 vascular dementia) from the Amsterdam Dementia Cohort, with available neuropsychology, APOE, MRI and [18F]florbetaben amyloid-PET. In our computerized decision support approach, using supervised machine learning based on the DSI classifier, we first classified the subjects using only neuropsychology, APOE, and quantified MRI. Then, for subjects with uncertain classification (probability of correct class (PCC) < 0.75) we enriched classification by adding (hypothetical) amyloid positive (AD-like) and negative (normal) PET visual read results and assessed whether the diagnosis became more certain in at least one scenario (PPC≥0.75). If this was the case, the actual visual read result was used in the final classification. We compared the proportion of PET scans and patients diagnosed with sufficient certainty in the computerized approach with three scenarios: 1) without amyloid-PET, 2) amyloid-PET according to the AUC, and 3) amyloid-PET for all patients.ResultsThe computerized approach advised PET in n = 60(21%) patients, leading to a diagnosis with sufficient certainty in n = 188(66%) patients. This approach was more efficient than the other three scenarios: 1) without amyloid-PET, diagnostic classification was obtained in n = 155(54%), 2) applying the AUC resulted in amyloid-PET in n = 113(40%) and diagnostic classification in n = 156(55%), and 3) performing amyloid-PET in all resulted in diagnostic classification in n = 154(54%).ConclusionOur computerized data-driven approach selected 21% of memory clinic patients for amyloid-PET, without compromising diagnostic performance. Our work contributes to a cost-effective implementation and could support clinicians in making a balanced decision in ordering additional amyloid PET during the dementia workup.

Abstract Background Frontotemporal lobar degeneration (FTLD) is characterized pathologically by neuronal and glial inclusions of hyperphosphorylated tau or by neuronal cytoplasmic inclusions of TDP43. This study aimed at deciphering the molecular mechanisms leading to these distinct pathological subtypes. Methods To this end, we performed an unbiased mass spectrometry-based proteomic and systems-level analysis of the middle frontal gyrus cortices of FTLD-tau (n = 6), FTLD-TDP (n = 15), and control patients (n = 5). We validated these results in an independent patient cohort (total n = 24). Results The middle frontal gyrus cortex proteome was most significantly altered in FTLD-tau compared to controls (294 differentially expressed proteins at FDR = 0.05). The proteomic modifications in FTLD-TDP were more heterogeneous (49 differentially expressed proteins at FDR = 0.1). Weighted co-expression network analysis revealed 17 modules of co-regulated proteins, 13 of which were dysregulated in FTLD-tau. These modules included proteins associated with oxidative phosphorylation, scavenger mechanisms, chromatin regulation, and clathrin-mediated transport in both the frontal and temporal cortex of FTLD-tau. The most strongly dysregulated subnetworks identified cyclin-dependent kinase 5 (CDK5) and polypyrimidine tract-binding protein 1 (PTBP1) as key players in the disease process. Dysregulation of 9 of these modules was confirmed in independent validation data sets of FLTD-tau and control temporal and frontal cortex (total n = 24). Dysregulated modules were primarily associated with changes in astrocyte and endothelial cell protein abundance levels, indicating pathological changes in FTD are not limited to neurons. Conclusions Using this innovative workflow and zooming in on the most strongly dysregulated proteins of the identified modules, we were able to identify disease-associated mechanisms in FTLD-tau with high potential as biomarkers and/or therapeutic targets.

Samenvatting Achtergrond: Computertools zoals digitale (web-based) cognitieve testen, diagnostische tools en automatisch gegenereerde hulpmiddelen voor het arts-patiëntgesprek voor de geheugenpolikliniek zijn in opkomst. Deze tools kunnen worden ingezet om clinici te ondersteunen bij de diagnostische besluitvorming en het communiceren van de diagnose en prognose. In dit onderzoek brengen we door middel van een vragenlijst de meningen van clinici, patiënten en naasten, de zogenoemde ‘eindgebruikers’, voor het gebruik van computertools in geheugenpoliklinieken in kaart. Daarnaast identificeren we belemmerende en faciliterende factoren voor de daadwerkelijke toepassing. Methode: Tussen juli en oktober 2020 nodigden we Europese clinici (n=109, leeftijd 45±10j; 47% vrouw) uit om deel te nemen aan een online vragenlijst. Een tweede vragenlijst werd verstuurd naar patiënten (n=50, leeftijd 73±8j, 34% vrouw) met subjectieve cognitieve klachten (SCD, n= 21), milde cognitieve achteruitgang (MCI, n=16) en dementie (n=13) en naasten (n=46, 65±12j, 54% vrouw). Resultaten: Driekwart van alle deelnemers was positief over het gebruik van computertools in geheugenpoliklinieken. Faciliterende factoren waren onder andere gebruiksvriendelijkheid en hogere diagnostische nauwkeurigheid. Onder barrières vielen (twijfels aan) betrouwbaarheid en validiteit en verlies van klinische autonomie. De deelnemers vinden dat tools moeten worden gebruikt ter aanvulling op de huidige werkwijze en niet als vervanging. Discussie: Onze resultaten vormen een belangrijke stap in het iteratieve ontwikkelproces van computertools voor geheugenpoliklinieken, dat samen met eindgebruikers doorlopen wordt. Abstract Introduction: Computer tools based on artificial intelligence could aid clinicians in memory clinics by supporting diagnostic decision-making and communicating diagnosis and prognosis. We aimed to identify preferences of end-users, and barriers and facilitators for using computer tools in memory clinics. Methods: Between July and October 2020, we invited European clinicians (n=109, age 45±10y; 47% female) to participate in an online questionnaire. A second questionnaire was sent to patients (n=50, age 73±8y, 34% female) with subjective cognitive complaints (SCD, n=21), mild cognitive impairment (MCI, n=16) and dementia (n=13) and care partners (n=46, 65±12y, 54% female). Results: The vast majority (75%) of all participants positively valued the use of computer tools in memory clinics. Facilitating factors included user-friendliness and increased diagnostic accuracy. Barriers included (doubts relating) reliability and validity of the tool and loss of clinical autonomy. The participants believe that tools should be used in addition to the current working method and not as a replacement. Discussion: Our results provide an important step in the iterative process of developing computer tools for memory clinics in co-creation with end-users and could guide successful implementation.

A role for cardiac sympathetic hyperinnervation in arrhythmogenesis after myocardial infarction (MI) has increasingly been recognized. In humans and mice, the heart receives cervical as well as thoracic sympathetic contributions. In mice, superior cervical ganglia (SCG) have been shown to contribute significantly to myocardial sympathetic innervation of the left ventricular anterior wall. Of interest, the SCG is situated adjacent to the carotid body (CB), a small organ involved in oxygen and metabolic sensing. We investigated the remodeling of murine SCG and CB over time after MI. Murine SCG were isolated from control mice, as well as 24 h, 3 days, 7 days and 6 weeks after MI. SCG and CBs were stained for the autonomic nervous system markers β3-tubulin, tyrosine hydroxylase (TH) and choline acetyltransferase (ChAT), as well as for the neurotrophic factors brain derived neurotropic factor (BDNF), nerve growth factor (NGF) and their tyrosine receptor kinase (pan TRK). Results show that after MI a significant increase in neuron size occurs, especially in the region bordering the CB. Co-expression of TH and ChAT is observed in SCG neuronal cells, but not in the CB. After MI, a significant decrease in ChAT intensity occurs, which negatively correlated with the increased cell size. In addition, an increase of BDNF and NGF at protein and mRNA levels was observed in both the CB and SCG. This upregulation of neurotropic factors coincides with the upregulation of their receptor within the SCG. These findings were concomitant with an increase in GAP43 expression in the SCG, which is known to contribute to axonal outgrowth and elongation. In conclusion, neuronal remodeling toward an increased adrenergic phenotype occurs in the SCG, which is possibly mediated by the CB and might contribute to pathological hyperinnervation after MI.

Purpose: Two serological assays, an Enzyme-Linked Immunosorbent Assay (ELISA) and a Lateral Flow Assay (LFA), have been developed based on the SARS-CoV-2 recombinant Receptor Binding Domain (RBD-ELISA) and the combination of Trimeric Spike (S) and Nucleoprotein (N), S-LFA and N-LFA, respectively, as candidate tools for both indirect measurement of virus circulation and assessment of infection and vaccine-induced immunity. Methods & Materials: A total of 1272 human serum samples collected from volunteers (SARS-CoV-2 infected, non-infected or vaccinated) were evaluated by the two assays. For the RBD-ELISA, plates were coated with RBD, sera were added at 1/5 dilution and bound antibodies were detected with RBD labelled with Horseradish Peroxidase. For the LFA, two parallel strips were used: one for detection of N-specific antibodies (Hoste A. el al, 2020); and another one for detection of S-specific antibodies, using S both as capture and detector reagent. Twenty microliters of blood or ten microliters of serum were applied to each cassette and results were interpreted after ten minutes.A seroneutralization assay was used as reference for the detection of neutralizing antibodies with RBD-ELISA and Reference sera (World Health Organization), for determination of the Limit of detection (LoD). MedCalc® 10 software was used for statistical analysis. Results: The potential diagnostic application with sera from naturally infected and non-infected volunteers showed sensitivity, specificity and agreement (kappa) values of 95.1%, 99.0% and 0.94 respectively for RBD-ELISA; while 97.2%, 99.3% and 0.967 respectively for N-LFA; or 93.2% 98.3 %, 0.923, respectively for S-LFA. Serum samples from vaccinated individuals were analyzed for the specific detection of antibodies to the S protein: for vaccinated but non-infected individuals, sensitivity reached 97.3% after 15 days post-second vaccination dose whereas for previously infected people reached 100% after only 15 days post-first dose. The performance of RBD-ELISA showed good agreement with seroneutralization and excellent agreement with S-LFA (kappa 0.979). Conclusion: The dual N/S LFA represents a valuable tool to detect SARS-CoV-2 infection due to its complementary information on N and S-specific antibody response. Furthermore, the S-LFA and RBD-ELISA are both proven to be able to determine the extent of antibody response after vaccination.

Pseudoxanthoma elasticum (PXE) is a multisystem ectopic mineralization disorder caused by pathogenic variants in the ABCC6 gene. Though complications of the disease can be treated, PXE itself remains currently intractable. A strategy for rapid and cost-effective discovery of therapeutic drugs would be to perform chemical compound screening using zebrafish, but this approach remains to be validated for PXE. In this paper, we validate a stable CRISPR/Cas9 abcc6a knockout zebrafish model–which has spinal column hypermineralization as its primary phenotypic feature–as a model system for compound screening in ectopic mineralization. We evaluated the anti-mineralization potential of five compounds, which had (anecdotal) positive effects reported in Abcc6 knockout mice and/or PXE patients. Abcc6a knockout zebrafish larvae were treated from 3 to 10 days post-fertilization with vitamin K1, sodium thiosulfate, etidronate, alendronate or magnesium citrate and compared to matching controls. Following alizarin red S staining, alterations in notochord sheath mineralization were semiquantified and found to largely congrue with the originally reported outcomes. Our results demonstrate that the use of this abcc6a knockout zebrafish model is a validated and promising strategy for drug discovery against ectopic mineralization.

Land subsidence in the Netherlands is an ongoing process. An increasing number of people and economic assets are exposed to subsidence and damage costs are soaring. In some areas tipping points have already been reached, where current land-use can no longer be maintained without considerable costs. A specific policy focusing on subsidence is lacking. Dealing with the societal impacts of subsidence is mainly the (implicit) responsibility of the public authorities that regulate the drivers of subsidence. As the societal impacts continue to occur and are increasing, discussions arise on the exact drivers of subsidence and responsibilities for the impacts on society. Our study aims to analyse whether and to what extent public decision-making, which controls land subsidence due to groundwater-table lowering and extraction of hydrocarbons and its societal impacts, is organised effectively to reduce these societal impacts, and how the legal framework can be improved to achieve that. By studying the respective legal frameworks of these drivers, we map legal solutions for mitigation of subsidence itself or adaptation to its societal impacts – both eventually aimed at reducing the societal impacts of subsidence. In this paper, we focus on the legal framework of one of these drivers: groundwater-table lowering.

BackgroundComputer tools based on artificial intelligence could aid clinicians in memory clinics in several ways, such as by supporting diagnostic decision-making, web-based cognitive testing, and the communication of diagnosis and prognosis. ObjectiveThis study aims to identify the preferences as well as the main barriers and facilitators related to using computer tools in memory clinics for all end users, that is, clinicians, patients, and care partners. MethodsBetween July and October 2020, we sent out invitations to a web-based survey to clinicians using the European Alzheimer’s Disease Centers network and the Dutch Memory Clinic network, and 109 clinicians participated (mean age 45 years, SD 10; 53/109, 48.6% female). A second survey was created for patients and care partners. They were invited via Alzheimer Europe, Alzheimer’s Society United Kingdom, Amsterdam Dementia Cohort, and Amsterdam Aging Cohort. A total of 50 patients with subjective cognitive decline, mild cognitive impairment, or dementia (mean age 73 years, SD 8; 17/34, 34% female) and 46 care partners (mean age 65 years, SD 12; 25/54, 54% female) participated in this survey. ResultsMost clinicians reported a willingness to use diagnostic (88/109, 80.7%) and prognostic (83/109, 76.1%) computer tools. User-friendliness (71/109, 65.1%); Likert scale mean 4.5, SD 0.7), and increasing diagnostic accuracy (76/109, 69.7%; mean 4.3, SD 0.7) were reported as the main factors stimulating the adoption of a tool. Tools should also save time and provide clear information on reliability and validity. Inadequate integration with electronic patient records (46/109, 42.2%; mean 3.8, SD 1.0) and fear of losing important clinical information (48/109, 44%; mean 3.7, SD 1.2) were most frequently indicated as barriers. Patients and care partners were equally positive about the use of computer tools by clinicians, both for diagnosis (69/96, 72%) and prognosis (73/96, 76%). In addition, most of them thought favorably regarding the possibility of using the tools themselves. ConclusionsThis study showed that computer tools in memory clinics are positively valued by most end users. For further development and implementation, it is essential to overcome the technical and practical barriers of a tool while paying utmost attention to its reliability and validity.

Introduction: Children with early brain damage or dysfunction are at risk of developing cerebral visual impairment (CVI), including visual processing dysfunctions (VPD), which currently remain largely undetected until school age. Our aim was to systematically screen for possible VPD in children born very or extremely preterm from 1 to 2 years corrected age (CA) and to evaluate the effectiveness of early referral.Method: We included N = 48 children born < 30 weeks from 1 year CA. They underwent a two-step VPD screening based on (1) neurological signs indicative of visual brain damage evaluated by neonatologists and/or pediatric neurologist and (2) a functional assessment of visual orienting functions (VOF) with an eye tracking-based test. If at least one of these assessments was abnormal for their age, the children were classified as a risk of VPD and referred to undergo conventional visual diagnostics: ophthalmic exam and visual function assessment (VFA). At 2 years CA, VOF screening was repeated and neurodevelopment was assessed.Results: 18 children (38%) were classified as at risk of VPD at 1 year CA. 7 children had abnormal neurological signs, 5 children had abnormal VOF, and 6 children had both. Subsequent ophthalmic exams (N = 14) showed severe hypermetropia in 21% and strabismus in 14%. VFA (N = 10) showed abnormal visual function and behavior in only 1 child. At 2 years CA, the total group showed an increase in abnormal VOF. Whereas the children at risk showed some normalization, the group without VPD risk at 1 year CA showed deterioration of VOF. Neurodevelopmental outcome did not clearly differ between risk groups.Conclusion: Our findings show a substantial risk of VPD during visual screening (in 38%) at 1 year CA, but relatively few deficits on subsequent conventional ophthalmic exams and VFA. The data suggest that most conventional visual diagnostic methods at this young age are not related to the established VPD risks. VOF assessment should be used complimentary to these methods. The fact that at 2 years CA the number of children with a VPD risk based on abnormal VOF increased argues for more extensive and continuous screening in risk groups, at least until school age.

In response to inflammatory cytokines and chemokines, monocytes differentiate into macrophages. Comprehensive analysis of gene expression regulation of neuronal guidance cue (NGC) ligands and receptors in the monocyte-to-macrophage differentiation process is not available yet. We performed transcriptome profiling in both human primary PBMCs/PBMC-derived macrophages and THP-1 cells/THP-1-macrophages using microarray or RNA sequencing methods. Pathway analysis showed that the axonal guidance pathway is significantly regulated upon monocyte differentiation. We confirmed NGC ligands and receptors which were consistently regulated, including SEMA4D, SEMA7A, NRP1, NRP2, PLXNA1 and PLXNA3. The involvement of RNA-binding protein quaking (QKI) in the regulation of NGC expression was investigated using monocytes and macrophages from a QKI haplo-insufficient patient and her healthy sibling. This revealed a positive correlation of SEMA7A expression with QKI expression. In silico analysis of 3′UTRs of NGCs proposed the competitive binding of QKI to proximal microRNA targeting sites as the mechanism of QKI-dependent regulation of SEMA7A. RNA immunoprecipitation confirmed an interaction of QKI with the 3′UTR of SEMA7A. Loss of SEMA7A resulted in monocyte differentiation towards a more anti-inflammatory macrophage. Taken together, the axonal guidance pathway is regulated during monocyte-to-macrophage differentiation, and the regulation is in line with the necessary functional adaption for the specialised role of macrophages.

Post-transcriptional control of RNA is important in health and disease. Here, the authors show that the RNA-binding protein Quaking guides pre-mRNA splicing and transcript abundance during monocyte to macrophage differentiation, and that Quaking depletion impairs pro-atherogenic foam cell formation.

Atherosclerosis is the underlying pathology in a major part of cardiovascular disease, the leading cause of mortality in developed countries. The infiltration of monocytes into the vessel walls of large arteries is a key denominator of atherogenesis, making monocytes accountable for the development of atherosclerosis. With the development of high-throughput transcriptome profiling platforms and cytometric methods for circulating cells, it is now feasible to study in-depth the predicted functional change of circulating monocytes reflected by changes of gene expression in certain pathways and correlate the changes to disease outcome. Neuroimmune guidance cues comprise a group of circulating- and cell membrane-associated signaling proteins that are progressively involved in monocyte functions. Here, we employed the CIRCULATING CELLS study cohort to classify cardiovascular disease patients and healthy individuals in relation to their expression of neuroimmune guidance cues in circulating monocytes. To cope with the complexity of human datasets featured by noisy data, nonlinearity and multidimensionality, we assessed various machine-learning methods. Of these, the linear discriminant analysis, Naïve Bayesian model and stochastic gradient boost model yielded perfect or near-perfect sensibility and specificity and revealed that expression levels of the neuroimmune guidance cues SEMA6B, SEMA6D and EPHA2 in circulating monocytes were of predictive values for cardiovascular disease outcome.

Eph receptors and their ephrin ligands are important guidance molecules during neurological and vascular development. In recent years, it has become clear that the Eph protein family remains functional in adult physiology. A subset of Ephs and ephrins is highly expressed by endothelial cells. As endothelial cells form the first barrier between the blood and surrounding tissues, maintenance of a healthy endothelium is crucial for tissue homeostasis. This review gives an overview of the current insights of the role of ephrin ligands and receptors in endothelial function and leukocyte recruitment in the (patho)physiology of adult vascular biology.

In the pathophysiologic setting of acute and chronic kidney injury, the excessive activation and recruitment of blood-borne monocytes prompts their differentiation into inflammatory macrophages, a process that leads to progressive glomerulosclerosis and interstitial fibrosis. Importantly, this differentiation of monocytes into macrophages requires the meticulous coordination of gene expression at both the transcriptional and post-transcriptional level. The transcriptomes of these cells are ultimately determined by RNA-binding proteins such as QUAKING (QKI), that define their pre-mRNA splicing and mRNA transcript patterns. Using two mouse models, namely (1) quaking viable mice (qkv) and (2) the conditional deletion in the myeloid cell lineage using the lysozyme 2-Cre (QKIFL/FL;LysM-Cre mice), we demonstrate that the abrogation of QKI expression in the myeloid cell lineage reduces macrophage infiltration following kidney injury induced by unilateral urethral obstruction (UUO). The qkv and QKIFL/FL;LysM-Cre mice both showed significant diminished interstitial collagen deposition and fibrosis in the UUO-damaged kidney, as compared to wild-type littermates. We show that macrophages isolated from QKIFL/FL;LysM-Cre mice are associated with defects in pre-mRNA splicing. Our findings demonstrate that reduced expression of the alternative splice regulator QKI in the cells of myeloid lineage attenuates renal interstitial fibrosis, suggesting that inhibition of this splice regulator may be of therapeutic value for certain kidney diseases.

In normal physiology, endothelial cells (ECs) form a vital barrier between the blood and underlying tissue controlling leukocyte diapedesis and vascular inflammation. Emerging data suggest that neuronal guidance cues, typically expressed during development, have roles outside the nervous system in vascular biology and immune responses. In particular, Class III semaphorins have been reported to affect EC migration and angiogenesis. While ECs express high levels of semaphorin 3F (SEMA3F), little is known about its function in mature ECs. Here we show that SEMA3F expression is reduced by inflammatory stimuli and increased by laminar flow. Endothelial cells exposed to laminar flow secrete SEMA3F, which subsequently binds to heparan sulfates on the surface of ECs. However, under pro-inflammatory conditions, reduced levels of SEMA3F make ECs more prone to monocyte diapedesis and display impaired barrier function as measured with an electric cell−substrate impedance sensing system and a microfluidic system. In addition, we demonstrate that SEMA3F can directly inhibit the migration of activated monocytes. Taken together, our data suggest an important homeostatic function for EC-expressed SEMA3F, serving as a mediator of endothelial quiescence.

Porcine reproductive failure, especially abortion, causes significant economic loss in the pig industry. Waddlia chondrophila and Parachlamydia acanthamoebae are potential abortigenic agents for pigs. Therefore, we investigated the presence of these two Chlamydia-like organisms in abortion-related samples originating from Belgian pig farms. All investigated samples remained negative.

Congenital portosystemic shunts are developmental anomalies of the splanchnic vascular system that cause portal blood to bypass the liver. Large-breed dogs are predisposed for intrahepatic portosystemic shunts (IHPSS) and small-breed dogs for extrahepatic portosystemic shunts (EHPSS). While the phenotype resulting from portal bypass of the liver of the two types of shunt is identical, the genotype and molecular pathways involved are probably different. The aim of this study was to gain insight into the pathways involved in the different types of portosystemic shunting. Microarray analysis of mRNA expression in liver tissue from dogs with EHPSS and IHPSS revealed that the expression of 26 genes was altered in either IHPSS or EHPSS samples compared with that in liver samples from control dogs. Quantitative real-time PCR of these genes in 14 IHPSS, 17 EHPSS, and 8 control liver samples revealed a significant differential expression of ACBP, CCBL1, GPC3, HAMP, PALLD, VCAM1, and WEE1. Immunohistochemistry and Western blotting confirmed an increased expression of VCAM1 in IHPSS but its absence in EHPSS, an increased WEE1 expression in IHPSS but not in EHPSS, and a decreased expression of CCBL1 in both shunt types. Regarding their physiologic functions, these findings may indicate a causative role for VCAM1 in EHPSS [corrected] and WEE1 for IHPSS. CCBL1 could be an interesting candidate to study not yet elucidated aspects in the pathophysiology of hepatic encephalopathy.

The aryl hydrocarbon receptor (AHR) mediates biological responses to toxic chemicals. An unexpected role for AHR in vascularization was suggested when mice lacking AHR displayed impaired closure of the ductus venosus after birth, as did knockout mice for aryl hydrocarbon receptor interacting protein (AIP) and aryl hydrocarbon receptor nuclear translocator (ARNT). The resulting intrahepatic portosystemic shunts (IHPSS) are frequently diagnosed in specific dog breeds, such as the Irish wolfhound. We compared the expression of components of the AHR pathway in healthy Irish wolfhounds and dogs with IHPSS. To this end, we analyzed the mRNA expression in the liver of AHR,AIP, ARNT, and other genes involved in this pathway, namely, those for aryl hydrocarbon receptor nuclear translocator 2 (ARNT2), hypoxia inducible factor 1alpha (HIF1A), heat shock protein 90AA1 (HSP90AA1), cytochromes P450 (CYP1A1, CYP1A2, and CYP1B1), vascular endothelial growth factor A (VEGFA), nitric oxide synthesase 3 (NOS3), and endothelin (EDN1). The observed low expression of AHR mRNA in the Irish wolfhounds is in associated with a LINE-1 insertion in intron 2, for which these dogs were homozygous. Down regulation in Irish wolfhounds was observed for AIP, ARNT2, CYP1A2, CYP1B1 and HSP90AA1 expression, whereas the expression of HIF1A was increased. Immunohistochemistry revealed lower levels of AHR, HIF1A, and VEGFA protein in the nucleus and lower levels of ARNT and HSP90AA1 protein in the cytoplasm of the liver cells of Irish wolfhounds. The impaired expression of HSP90AA1 could trigger the observed differences in mRNA and protein levels and therefore explain the link between two very different functions of AHR: regulation of the closure of the ductus venosus and the response to toxins.