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Background and Purpose: Radiation induced cardiotoxicity (RICT) is as an important sequela of radiotherapy to the thorax for patients. In this study, we aim to investigate the dose and fractionation response of RICT. We propose global longitudinal strain (GLS) as an early indicator of RICT and investigate myocardial deformation following irradiation., Methods: RICT was investigated in female C57BL/6J mice in which the base of the heart was irradiated under image-guidance using a small animal radiation research platform (SARRP). Mice were randomly assigned to a treatment group: single-fraction dose of 16 Gy or 20 Gy, 3 consecutive fractions of 8.66 Gy, or sham irradiation; biological effective doses (BED) used were 101.3 Gy, 153.3 Gy and 101.3 Gy respectively. Longitudinal transthoracic echocardiography (TTE) was performed from baseline up to 50 weeks post-irradiation to detect structural and functional effects., Results: Irradiation of the heart base leads to BED-dependent changes in systolic and diastolic function 50 weeks post-irradiation. GLS showed significant decreases in a BED-dependent manner for all irradiated animals, as early as 10 weeks after irradiation. Early changes in GLS indicate late changes in cardiac function. BED-independent increases were observed in the left ventricle (LV) mass and volume and myocardial fibrosis., Conclusions: Functional features of RICT displayed a BED dependence in this study. GLS showed an early change at 10 weeks post-irradiation. Cardiac remodelling was observed as increases in mass and volume of the LV, further supporting our hypothesis that dose to the base of the heart drives the global heart toxicity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Purpose: Despite technological advances in radiotherapy (RT), cardiotoxicity remains a common complication in patients with lung, oesophageal and breast cancers. Statin therapy has been shown to have pleiotropic properties beyond its lipid-lowering effects. Previous murine models have shown statin therapy can reduce short-term functional effects of whole-heart irradiation. In this study, we assessed the efficacy of atorvastatin in protecting against the late effects of radiation exposure on systolic function, cardiac conduction, and atrial natriuretic peptide (ANP) following a clinically relevant partial-heart radiation exposure., Materials and Methods: Female, 12-week old, C57BL/6j mice received an image-guided 16 Gy X-ray field to the base of the heart using a small animal radiotherapy research platform (SARRP), with or without atorvastatin from 1 week prior to irradiation until the end of the experiment. The animals were followed for 50 weeks with longitudinal transthoracic echocardiography (TTE) and electrocardiography (ECG) every 10 weeks, and plasma ANP every 20 weeks., Results: At 30-50 weeks, mild left ventricular systolic function impairment observed in the RT control group was less apparent in animals receiving atorvastatin. ECG analysis demonstrated prolongation of components of cardiac conduction related to the heart base at 10 and 30 weeks in the RT control group but not in animals treated with atorvastatin. In contrast to systolic function, conduction disturbances resolved at later time-points with radiation alone. ANP reductions were lower in irradiated animals receiving atorvastatin at 30 and 50 weeks., Conclusions: Atorvastatin prevents left ventricular systolic dysfunction, and the perturbation of cardiac conduction following partial heart irradiation. If confirmed in clinical studies, these data would support the use of statin therapy for cardioprotection during thoracic radiotherapy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Dysregulation of nitric oxide (NO) production can cause ischaemic retinal injury and result in blindness. How this dysregulation occurs is poorly understood but thought to be due to an impairment in NO synthase function (NOS) and nitro-oxidative stress. Here we investigated the possibility of correcting this defective NOS activity by supplementation with the cofactor tetrahydrobiopterin, BH 4 . Retinal ischaemia was examined using the oxygen-induced retinopathy model and BH 4 deficient Hph-1 mice used to establish the relationship between NOS activity and BH 4 . Mice were treated with the stable BH 4 precursor sepiapterin at the onset of hypoxia and their retinas assessed 48 h later. HPLC analysis confirmed elevated BH 4 levels in all sepiapterin supplemented groups and increased NOS activity. Sepiapterin treatment caused a significant decrease in neuronal cell death in the inner nuclear layer that was most notable in WT animals and was associated with significantly diminished superoxide and local peroxynitrite formation. Interestingly, sepiapterin also increased inflammatory cytokine levels but not microglia cell number. BH 4 supplementation by sepiapterin improved both redox state and neuronal survival during retinal ischaemia, in spite of a paradoxical increase in inflammatory cytokines. This implicates nitro-oxidative stress in retinal neurones as the cytotoxic element in ischaemia, rather than enhanced pro-inflammatory signalling., (© 2023. Crown.)

Ischaemic cardiovascular disease is associated with tissue hypoxia as a significant determinant of angiogenic dysfunction and adverse remodelling. While cord blood-derived endothelial colony-forming cells (CB-ECFCs) hold clear therapeutic potential due to their enhanced angiogenic and proliferative capacity, their impaired functionality within the disease microenvironment represents a major barrier to clinical translation. The aim of this study was to define the specific contribution of NOX4 NADPH oxidase, which we previously reported as a key CB-ECFC regulator, to hypoxia-induced dysfunction and its potential as a therapeutic target. CB-ECFCs exposed to experimental hypoxia demonstrated downregulation of NOX4-mediated reactive oxygen species (ROS) signalling linked with a reduced tube formation, which was partially restored by NOX4 plasmid overexpression. siRNA knockdown of placenta-specific 8 (PLAC8), identified by microarray analysis as an upstream regulator of NOX4 in hypoxic versus normoxic CB-ECFCs, enhanced tube formation, NOX4 expression and hydrogen peroxide generation, and induced several key transcription factors associated with downstream Nrf2 signalling. Taken together, these findings indicated that activation of the PLAC8-NOX4 signalling axis improved CB-ECFC angiogenic functions in experimental hypoxia, highlighting this pathway as a potential target for protecting therapeutic cells against the ischaemic cardiovascular disease microenvironment.

Ixodes ricinus ticks are Scandinavia's main vector for tick-borne encephalitis virus (TBEV), which infects many people annually. The aims of the present study were (i) to obtain information on the TBEV prevalence in host-seeking I. ricinus collected within the Øresund-Kattegat-Skagerrak (ØKS) region, which lies in southern Norway, southern Sweden and Denmark; (ii) to analyse whether there are potential spatial patterns in the TBEV prevalence; and (iii) to understand the relationship between TBEV prevalence and meteorological factors in southern Scandinavia. Tick nymphs were collected in 2016, in southern Scandinavia, and screened for TBEV, using pools of 10 nymphs, with RT real-time PCR, and positive samples were confirmed with pyrosequencing. Spatial autocorrelation and cluster analysis was performed with Global Moran's I and SatScan to test for spatial patterns and potential local clusters of the TBEV pool prevalence at each of the 50 sites. A climatic analysis was made to correlate parameters such as minimum, mean and maximum temperature, relative humidity and saturation deficit with TBEV pool prevalence. The climatic data were acquired from the nearest meteorological stations for 2015 and 2016. This study confirms the presence of TBEV in 12 out of 30 locations in Denmark, where six were from Jutland, three from Zealand and two from Bornholm and Falster counties. In total, five out of nine sites were positive from southern Sweden. TBEV prevalence of 0.7%, 0.5% and 0.5%, in nymphs, was found at three sites along the Oslofjord (two sites) and northern Skåne region (one site), indicating a potential concern for public health. We report an overall estimated TBEV prevalence of 0.1% in questing I. ricinus nymphs in southern Scandinavia with a region-specific prevalence of 0.1% in Denmark, 0.2% in southern Sweden and 0.1% in southeastern Norway. No evidence of a spatial pattern or local clusters was found in the study region. We found a strong correlation between TBEV prevalence in ticks and relative humidity in Sweden and Norway, which might suggest that humidity has a role in maintaining TBEV prevalence in ticks. TBEV is an emerging tick-borne pathogen in southern Scandinavia, and we recommend further studies to understand the TBEV transmission potential with changing climate in Scandinavia., (© 2023 The Authors. Zoonoses and Public Health published by Wiley-VCH GmbH.)

Purpose: Radiation cardiotoxicity (RC) is a clinically significant adverse effect of treatment for patients with thoracic malignancies. Clinical studies in lung cancer have indicated that heart substructures are not uniformly radiosensitive, and that dose to the heart base drives RC. In this study, we aimed to characterize late changes in gene expression using spatial transcriptomics in a mouse model of base regional radiosensitivity., Methods and Materials: An aged female C57BL/6 mouse was irradiated with 16 Gy delivered to the cranial third of the heart using a 6 × 9 mm parallel opposed beam geometry on a small animal radiation research platform, and a second mouse was sham-irradiated. After echocardiography, whole hearts were collected at 30 weeks for spatial transcriptomic analysis to map gene expression changes occurring in different regions of the partially irradiated heart. Cardiac regions were manually annotated on the capture slides and the gene expression profiles compared across different regions., Results: Ejection fraction was reduced at 30 weeks after a 16 Gy irradiation to the heart base, compared with the sham-irradiated controls. There were markedly more significant gene expression changes within the irradiated regions compared with nonirradiated regions. Variation was observed in the transcriptomic effects of radiation on different cardiac base structures (eg, between the right atrium [n = 86 dysregulated genes], left atrium [n = 96 dysregulated genes], and the vasculature [n = 129 dysregulated genes]). Disrupted biological processes spanned extracellular matrix as well as circulatory, neuronal, and contractility activities., Conclusions: This is the first study to report spatially resolved gene expression changes in irradiated tissues. Examination of the regional radiation response in the heart can help to further our understanding of the cardiac base's radiosensitivity and support the development of actionable targets for pharmacologic intervention and biologically relevant dose constraints., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Rodent control is necessary to prevent damage and spread of disease, and the most common pesticides used for urban and rural rodent control are anticoagulant rodenticides. The aim of this present study was to present data on suspected exposure to rodenticides in humans and domestic animals in Norway based on inquiries to the Norwegian Poison Information Centre in the 16-year period from 2005 through 2020. A total of 4235 inquiries regarding suspected exposures to rodenticides were registered in the study period. Of these, 1486 inquiries involved humans and 2749 animals. Second generation anticoagulants were involved in 68% of human exposures and 79% of animal exposures. Dogs were the most frequent species involved in the animal exposures with 93% of the inquiries, while cats were second most frequent involved. Around 50% of the human inquiries concerned children at the age of 0-4 years. Only 2% of the cases were in the age group 10-19 years, while adults comprised 35% of the inquiries. Acute poisonings accounted for almost 100% of the inquiries among both humans and animals. The exposure was accidental in 99% of the animal exposures and in 85% of the human exposures. In humans, only 14 inquiries were regarding occupational related accidents. Misdeed or self-inflicted injury accounted for 15% of the human inquiries and were the cause of 79% of the severe poisonings. Severe poisoning was only assessed in 1% of the cases involving children under 5 years. In contrast, 17% of the inquiries concerning adults (≥20 years) were assessed as severe. Subsequently, to prevent human and animal rodenticide exposure, we urge the use of non-chemical methods such as sanitation, rodent proofing (a form of construction which will impede or prevent rodents access to or from a given space or building) and mechanical traps. Restricting the use of rodenticides to professional pest controllers (or other persons with authorisation), reinforcing high quality education of these persons, and securing compliance of the best codes of practice could be advocated to reduce accidental exposure to rodenticides in humans and animals., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Soleng et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Loss of retinal blood flow autoregulation is an early feature of diabetes that precedes the development of clinically recognizable diabetic retinopathy (DR). Retinal blood flow autoregulation is mediated by the myogenic response of the retinal arterial vessels, a process that is initiated by the stretch‑dependent activation of TRPV2 channels on the retinal vascular smooth muscle cells (VSMCs). Here, we show that the impaired myogenic reaction of retinal arterioles from diabetic animals is associated with a complete loss of stretch‑dependent TRPV2 current activity on the retinal VSMCs. This effect could be attributed, in part, to TRPV2 channel downregulation, a phenomenon that was also evident in human retinal VSMCs from diabetic donors. We also demonstrate that TRPV2 heterozygous rats, a nondiabetic model of impaired myogenic reactivity and blood flow autoregulation in the retina, develop a range of microvascular, glial, and neuronal lesions resembling those observed in DR, including neovascular complexes. No overt kidney pathology was observed in these animals. Our data suggest that TRPV2 dysfunction underlies the loss of retinal blood flow autoregulation in diabetes and provide strong support for the hypothesis that autoregulatory deficits are involved in the pathogenesis of DR.

Background: Mosquito-borne viruses pose a serious threat to humans worldwide. There has been an upsurge in the number of mosquito-borne viruses in Europe, mostly belonging to the families Togaviridae, genus Alphavirus (Sindbis, Chikungunya), Flaviviridae (West Nile, Usutu, Dengue), and Peribunyaviridae, genus Orthobunyavirus, California serogroup (Inkoo, Batai, Tahyna). The principal focus of this study was Inkoo (INKV) and Sindbis (SINV) virus circulating in Norway, Sweden, Finland, and some parts of Russia. These viruses are associated with morbidity in humans. However, there is a knowledge gap regarding reservoirs and transmission. Therefore, we aimed to determine the prevalence of INKV and SINV in blood sucking insects and seroprevalence for INKV in semi-domesticated Eurasian tundra reindeer (Rangifer tarandus tarandus) in Norway., Materials and Methods: In total, 213 pools containing about 25 blood sucking insects (BSI) each and 480 reindeer sera were collected in eight Norwegian reindeer summer pasture districts during 2013-2015. The pools were analysed by RT-PCR to detect INKV and by RT-real-time PCR for SINV. Reindeer sera were analysed for INKV-specific IgG by an Indirect Immunofluorescence Assay (n = 480, IIFA) and a Plaque Reduction Neutralization Test (n = 60, PRNT)., Results: Aedes spp. were the most dominant species among the collected BSI. Two of the pools were positive for INKV-RNA by RT-PCR and were confirmed by pyrosequencing. The overall estimated pool prevalence (EPP) of INKV in Norway was 0.04%. None of the analysed pools were positive for SINV. Overall IgG seroprevalence in reindeer was 62% positive for INKV by IIFA. Of the 60 reindeer sera- analysed by PRNT for INKV, 80% were confirmed positive, and there was no cross-reactivity with the closely related Tahyna virus (TAHV) and Snowshoe hare virus (SSHV)., Conclusion: The occurrence and prevalence of INKV in BSI and the high seroprevalence against the virus among semi-domesticated reindeer in Norway indicate that further studies are required for monitoring this virus. SINV was not detected in the BSI in this study, however, human cases of SINV infection are yearly reported from other regions such as Rjukan in south-central Norway. It is therefore essential to monitor both viruses in the human population. Our findings are important to raise awareness regarding the geographical distribution of these mosquito-borne viruses in Northern Europe., (© 2022. The Author(s).)

Evolutionarily conserved signaling intermediate in Toll pathways (ECSIT) is a protein with roles in early development, activation of the transcription factor NF-κB, and production of mitochondrial reactive oxygen species (mROS) that facilitates clearance of intracellular bacteria like Salmonella. ECSIT is also an important assembly factor for mitochondrial complex I. Unlike the murine form of Ecsit (mEcsit), we demonstrate here that human ECSIT (hECSIT) is highly labile. To explore whether the instability of hECSIT affects functions previously ascribed to its murine counterpart, we created a potentially novel transgenic mouse in which the murine Ecsit gene is replaced by the human ECSIT gene. The humanized mouse has low levels of hECSIT protein, in keeping with its intrinsic instability. Whereas low-level expression of hECSIT was capable of fully compensating for mEcsit in its roles in early development and activation of the NF-κB pathway, macrophages from humanized mice showed impaired clearance of Salmonella that was associated with reduced production of mROS. Notably, severe cardiac hypertrophy was manifested in aging humanized mice, leading to premature death. The cellular and molecular basis of this phenotype was delineated by showing that low levels of human ECSIT protein led to a marked reduction in assembly and activity of mitochondrial complex I with impaired oxidative phosphorylation and reduced production of ATP. Cardiac tissue from humanized hECSIT mice also showed reduced mitochondrial fusion and more fission but impaired clearance of fragmented mitochondria. A cardiomyocyte-intrinsic role for Ecsit in mitochondrial function and cardioprotection is also demonstrated. We also show that cardiac fibrosis and damage in humans correlated with low expression of human ECSIT. In summary, our findings identify a role for ECSIT in cardioprotection, while generating a valuable experimental model to study mitochondrial dysfunction and cardiac pathophysiology.

Tick-borne pathogens cause diseases in animals and humans, and tick-borne disease incidence is increasing in many parts of the world. There is a need to assess the distribution of tick-borne pathogens and identify potential risk areas. We collected 29,440 tick nymphs from 50 sites in Scandinavia from August to September, 2016. We tested ticks in a real-time PCR chip, screening for 19 vector-associated pathogens. We analysed spatial patterns, mapped the prevalence of each pathogen and used machine learning algorithms and environmental variables to develop predictive prevalence models. All 50 sites had a pool prevalence of at least 33% for one or more pathogens, the most prevalent being Borrelia afzelii, B. garinii, Rickettsia helvetica, Anaplasma phagocytophilum, and Neoehrlichia mikurensis. There were large differences in pathogen prevalence between sites, but we identified only limited geographical clustering. The prevalence models performed poorly, with only models for R. helvetica and N. mikurensis having moderate predictive power (normalized RMSE from 0.74-0.75, R 2 from 0.43-0.48). The poor performance of the majority of our prevalence models suggest that the used environmental and climatic variables alone do not explain pathogen prevalence patterns in Scandinavia, although previously the same variables successfully predicted spatial patterns of ticks in the same area.

Background and Purpose: Radiation-induced cardiac toxicity (RICT) remains one of the most critical dose limiting constraints in radiotherapy. Recent studies have shown higher doses to the base of the heart are associated with worse overall survival in lung cancer patients receiving radiotherapy. This work aimed to investigate the impact of sub-volume heart irradiation in a mouse model using small animal image-guided radiotherapy., Materials and Methods: C57BL/6 mice were irradiated with a single fraction of 16 Gy to the base, middle or apex of the heart using a small animal radiotherapy research platform. Cone beam CT and echocardiography were performed at baseline and at 10 week intervals until 50 weeks post-treatment. Structural and functional parameters were correlated with mean heart dose (MHD) and volume of heart receiving 5 Gy (V5)., Results: All irradiated mice showed a time dependent increase in left ventricle wall thickness in diastole of ~0.2 mm detected at 10 weeks post-treatment, with the most significant and persistent changes occurring in the heart base-irradiated animals. Similarly, statistically different functional effects (p < 0.01) were observed in base-irradiated animals which showed the most significant decreases compared to controls. The observed functional changes did not correlate with MHD and V5 (R 2  < 0.1), indicating that whole heart dosimetry parameters do not predict physiological changes resulting from cardiac sub-volume irradiation., Conclusions: This is the first report demonstrating the structural and functional consequences of sub-volume targeting in the mouse heart and reverse translates clinical observations indicating the heart base as a critical radiosensitive region., (Copyright © 2020 Elsevier B.V. All rights reserved.)

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Ticks carry pathogens that can cause disease in both animals and humans, and there is a need to monitor the distribution and abundance of ticks and the pathogens they carry to pinpoint potential high risk areas for tick-borne disease transmission. In a joint Scandinavian study, we measured Ixodes ricinus instar abundance at 159 sites in southern Scandinavia in August-September, 2016, and collected 29,440 tick nymphs at 50 of these sites. We additionally measured abundance at 30 sites in August-September, 2017. We tested the 29,440 tick nymphs in pools of 10 in a Fluidigm real-time PCR chip to screen for 17 different tick-associated pathogens, 2 pathogen groups and 3 tick species. We present data on the geolocation, habitat type and instar abundance of the surveyed sites, as well as presence/absence of each pathogen in all analysed pools from the 50 collection sites and individual prevalence for each site. These data can be used alone or in combination with other data for predictive modelling and mapping of high-risk areas.

Pressure overload-induced left ventricular hypertrophy (LVH) is initially adaptive but ultimately promotes systolic dysfunction and chronic heart failure. Whilst underlying pathways are incompletely understood, increased reactive oxygen species generation from Nox2 NADPH oxidases, and metabolic remodelling, largely driven by PPARα downregulation, are separately implicated. Here, we investigated interaction between the two as a key regulator of LVH using in vitro, in vivo and transcriptomic approaches. Phenylephrine-induced H9c2 cardiomyoblast hypertrophy was associated with reduced PPARα expression and increased Nox2 expression and activity. Pressure overload-induced LVH and systolic dysfunction induced in wild-type mice by transverse aortic constriction (TAC) for 7 days, in association with Nox2 upregulation and PPARα downregulation, was enhanced in PPARα -/- mice and prevented in Nox2 -/- mice. Detailed transcriptomic analysis revealed significantly altered expression of genes relating to PPARα, oxidative stress and hypertrophy pathways in wild-type hearts, which were unaltered in Nox2 -/- hearts, whilst oxidative stress pathways remained dysregulated in PPARα -/- hearts following TAC. Network analysis indicated that Nox2 was essential for PPARα downregulation in this setting and identified preferential inflammatory pathway modulation and candidate cytokines as upstream Nox2-sensitive regulators of PPARα signalling. Together, these data suggest that Nox2 is a critical driver of PPARα downregulation leading to maladaptive LVH., Competing Interests: The authors declare no conflict of interest.

The tick-borne encephalitis virus (TBEV), a zoonotic flaviviral infection, is endemic in large parts of Norway and Eurasia. Humans are mainly infected with TBEV via bites from infected ticks. In Norway, the main geographical distribution of ticks is along the Norwegian coastline from southeast (~59°N) and up to the southern parts of Nordland County (~65°N). In this study, we collected ticks by flagging along the coast from Østfold County to Nordland County. By whole-genome sequencing of the mitochondrial genome of Ixodes ricinus, the phylogenetic tree suggests that there is limited phylogeographic structure both in Norway and in Europe. The overall TBEV prevalence is 0.3% for nymphs and 4.3% for adults. The highest estimated TBEV prevalence in adult ticks was detected in Rogaland and Vestfold County, while for nymphs it is highest in Vestfold, Vest-Agder and Rogaland. The present work is one of the largest studies on distribution and prevalence of TBEV in ticks in Scandinavia, showing that the virus is wider distributed in Norway than previously anticipated., (© 2020 Blackwell Verlag GmbH.)

Neoehrlichia mikurensis is a tick-borne pathogen widespread among ticks and rodents in Europe and Asia. A previous study on Ixodes ricinus ticks in Norway suggested that N. mikurensis was scarce or absent on the south-west coast of Norway, but abundant elsewhere. The aim of this study was to further investigate the prevalence and distribution of N. mikurensis along the western seaboard of Norway in comparison with more eastern and northern areas. The second aim of the study was to examine seasonal variation of the bacterium in one specific location in the south-eastern part of Norway. Questing I. ricinus were collected from 13 locations along the coast of Norway, from Brønnøysund in Nordland County to Spjaerøy in Østfold County. In total, 11,113 nymphs in 1,113 pools and 718 individual adult ticks were analysed for N. mikurensis by real-time PCR. The mean prevalence of N. mikurensis in adult ticks was 7.9% while the estimated pooled prevalence in nymphs was 3.5%. The prevalence ranged from 0% to 25.5%, with the highest prevalence in the southernmost and the northernmost locations. The pathogen was absent, or present only at low prevalence (<5%), at eight locations, all located in the west, from 58.9°N to 64.9°N. The prevalence of N. mikurensis was significantly different between counties (p < .0001). No significant seasonal variation of N. mikurensis prevalence was observed in the period May to October 2015. Our results confirm earlier findings of a low prevalence of N. mikurensis in the western seaboard of Norway., (© 2019 The Authors. Zoonoses and Public Health published by Blackwell Verlag GmbH.)

Aims: Cord blood-derived endothelial colony-forming cells (CB-ECFCs) are a defined progenitor population with established roles in vascular homeostasis and angiogenesis, which possess low immunogenicity and high potential for allogeneic therapy and are highly sensitive to regulation by reactive oxygen species (ROS). The aim of this study was to define the precise role of the major ROS-producing enzyme, NOX4 NADPH oxidase, in CB-ECFC vasoreparative function., Methods and Results: In vitro CB-ECFC migration (scratch-wound assay) and tubulogenesis (tube length, branch number) was enhanced by phorbol 12-myristate 13-acetate (PMA)-induced superoxide in a NOX-dependent manner. CB-ECFCs highly-expressed NOX4, which was further induced by PMA, whilst NOX4 siRNA and plasmid overexpression reduced and potentiated in vitro function, respectively. Increased ROS generation in NOX4-overexpressing CB-ECFCs (DCF fluorescence, flow cytometry) was specifically reduced by superoxide dismutase, highlighting induction of ROS-specific signalling. Laser Doppler imaging of mouse ischaemic hindlimbs at 7 days indicated that NOX4-knockdown CB-ECFCs inhibited blood flow recovery, which was enhanced by NOX4-overexpressing CB-ECFCs. Tissue analysis at 14 days revealed consistent alterations in vascular density (lectin expression) and eNOS protein despite clearance of injected CB-ECFCs, suggesting NOX4-mediated modulation of host tissue. Indeed, proteome array analysis indicated that NOX4-knockdown CB-ECFCs largely suppressed tissue angiogenesis, whilst NOX4-overexpressing CB-ECFCs up-regulated a number of pro-angiogenic factors specifically-linked with eNOS signalling, in parallel with equivalent modulation of NOX-dependent ROS generation, suggesting that CB-ECFC NOX4 signalling may promote host vascular repair., Conclusion: Taken together, these findings indicate a key role for NOX4 in CB-ECFCs, thereby highlighting its potential as a target for enhancing their reparative function through therapeutic priming to support creation of a pro-reparative microenvironment and effective post-ischaemic revascularization., (© The Author(s) 2019. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Recently, focus on tick-borne diseases has increased as ticks and their pathogens have become widespread and represent a health problem in Europe. Understanding the epidemiology of tick-borne infections requires the ability to predict and map tick abundance. We measured Ixodes ricinus abundance at 159 sites in southern Scandinavia from August-September, 2016. We used field data and environmental variables to develop predictive abundance models using machine learning algorithms, and also tested these models on 2017 data. Larva and nymph abundance models had relatively high predictive power (normalized RMSE from 0.65-0.69, R 2 from 0.52-0.58) whereas adult tick models performed poorly (normalized RMSE from 0.94-0.96, R 2 from 0.04-0.10). Testing the models on 2017 data produced good results with normalized RMSE values from 0.59-1.13 and R 2 from 0.18-0.69. The resulting 2016 maps corresponded well with known tick abundance and distribution in Scandinavia. The models were highly influenced by temperature and vegetation, indicating that climate may be an important driver of I. ricinus distribution and abundance in Scandinavia. Despite varying results, the models predicted abundance in 2017 with high accuracy. The models are a first step towards environmentally driven tick abundance models that can assist in determining risk areas and interpreting human incidence data.

Background: Candidatus Neoehrlichia mikurensis is an emerging tick-borne pathogen. It is widely distributed in Ixodes ricinus ticks in Europe, but knowledge of its distribution in Norway, where I. ricinus reaches its northern limit, is limited. In this study we have developed a real time PCR test for Ca. N. mikurensis and used it to investigate the distribution of Ca. N. mikurensis in Norway., Results: Real time PCR targeting the groEL gene was developed and shown to be highly sensitive. It was used to detect Ca. N. mikurensis in 1651 I. ricinus nymphs and adults collected from twelve locations in Norway, from the eastern Oslo Fjord in the south to near the Arctic Circle in the north. The overall prevalence was 6.5% and varied locally between 0 and 16%. Prevalence in adults and nymphs was similar, suggesting that ticks acquire Ca. N. mikurensis predominantly during their first blood meal. In addition, 123 larvae were investigated; Ca. N. mikurensis was not found in larvae, suggesting that transovarial transmission is rare or absent. Sequence analysis suggests that a single variant dominates in Norway., Conclusions: Ca. N. mikurensis is widespread and common in ticks in Norway and reaches up to their northern limit near the Arctic Circle. Ticks appear to acquire Ca. N. mikurensis during their first blood meal. No evidence for transovarial transmission was found.

BackgroundTick-borne diseases have become increasingly common in recent decades and present a health problem in many parts of Europe. Control and prevention of these diseases require a better understanding of vector distribution.AimOur aim was to create a model able to predict the distribution of Ixodes ricinus nymphs in southern Scandinavia and to assess how this relates to risk of human exposure.MethodsWe measured the presence of I. ricinus tick nymphs at 159 stratified random lowland forest and meadow sites in Denmark, Norway and Sweden by dragging 400 m transects from August to September 2016, representing a total distance of 63.6 km. Using climate and remote sensing environmental data and boosted regression tree modelling, we predicted the overall spatial distribution of I. ricinus nymphs in Scandinavia. To assess the potential public health impact, we combined the predicted tick distribution with human density maps to determine the proportion of people at risk.ResultsOur model predicted the spatial distribution of I. ricinus nymphs with a sensitivity of 91% and a specificity of 60%. Temperature was one of the main drivers in the model followed by vegetation cover. Nymphs were restricted to only 17.5% of the modelled area but, respectively, 73.5%, 67.1% and 78.8% of the human populations lived within 5 km of these areas in Denmark, Norway and Sweden.ConclusionThe model suggests that increasing temperatures in the future may expand tick distribution geographically in northern Europe, but this may only affect a small additional proportion of the human population.

The aim of this study was to determine the occurrence of tick-borne pathogens of medical importance in questing ticks collected from five recreationally used islands along the Norwegian coastline. Furthermore, since coinfection may affect the disease severity, this study aimed to determine the extent of coinfection in individual ticks or co-localization of tick-borne pathogens. In all, 4158 questing Ixodes ricinus ticks were analyzed. For detection of tick-borne encephalitis virus (TBEV), nymphs (3690) were analyzed in pools of ten. To detect Borrelia burgdorferi sensu lato, B. miyamotoi, Anaplasma phagocytophilum and Candidatus Neoehrlichia mikurensis, 468 nymphs were analyzed individually. A total of five nymph pools was infected with TBEV, giving an overall prevalence of 0.14%. In the individually analyzed ticks, B. burgdorferi s. l. (15.6%), Candidatus N. mikurensis (11%), A. phagocytophilum (1.4%) and B. miyamotoi (0.9%) were detected. Coinfection was found in 3.3% of the ticks, and the only dual infection observed was with B. afzelii and Candidatus N. mikurensis. This association was significantly higher than what would occur by random chance., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Despite being first described 45 years ago, the existence of a distinct diabetic cardiomyopathy remains controversial. Nonetheless, it is widely accepted that the diabetic heart undergoes characteristic structural and functional changes in the absence of ischaemia and hypertension, which are independently linked to heart failure progression and are likely to underlie enhanced susceptibility to stress. A prominent feature is marked collagen accumulation linked with inflammation and extensive extracellular matrix changes, which appears to be the main factor underlying cardiac stiffness and subclinical diastolic dysfunction, estimated to occur in as many as 75% of optimally controlled diabetics. Whether this characteristic remodelling phenotype is primarily driven by microvascular dysfunction or alterations in cardiomyocyte metabolism remains unclear. Although hyperglycaemia regulates multiple pathways in the diabetic heart, increased reactive oxygen species (ROS) generation is thought to represent a central mechanism underlying associated adverse remodelling. Indeed, experimental and clinical diabetes are linked with oxidative stress which plays a key role in cardiomyopathy, while key processes underlying diabetic cardiac remodelling, such as inflammation, angiogenesis, cardiomyocyte hypertrophy and apoptosis, fibrosis and contractile dysfunction, are redox sensitive. This review will explore the relative contributions of the major ROS sources (dysfunctional nitric oxide synthase, mitochondria, xanthine oxidase, nicotinamide adenine dinucleotide phosphate oxidases) in the diabetic heart and the potential for therapeutic targeting of ROS signalling using novel pharmacological and non-pharmacological approaches to modify specific aspects of the remodelling phenotype in order to prevent and/or delay heart failure development and progression., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

This study investigated the geographical distribution of Ixodes ricinus and prevalence of the tick-borne encephalitis virus (TBEV) in northern Norway. Flagging for questing I. ricinus ticks was performed in areas ranging from Vikna in Nord-Trøndelag County, located 190km south of the Arctic Circle (66.3°N), to Steigen in Nordland County, located 155km north of the Arctic Circle. We found that ticks were abundant in both Vikna (64.5°N) and Brønnøy (65.1°N). Only a few ticks were found at locations ∼66°N, and no ticks were found at several locations up to 67.5°N. Real-time PCR (RT-PCR) analyses of the collected ticks (nymphs and adults) for the presence of TBEV revealed a low prevalence (0.1%) of TBEV among the nymphs collected in Vikna, while a prevalence of 0% to 3% was found among nymphs collected at five locations in Brønnøy. Adult ticks collected in Vikna and Brønnøy had higher rates of TBEV infection (8.6% and 0%-9.0%, respectively) than the nymphs. No evidence of TBEV was found in the few ticks collected further north of Brønnøy. This is the first report of TBEV being detected at locations up to 65.1°N. It remains to be verified whether viable populations of I. ricinus exist at locations north of 66°N. Future studies are warranted to increase our knowledge concerning tick distribution, tick abundance, and tick-borne pathogens in northern Norway., (Copyright © 2017 Elsevier GmbH. All rights reserved.)

Background and Purpose: The anthracycline doxorubicin (DOX), although successful as a first-line cancer treatment, induces cardiotoxicity linked with increased production of myocardial ROS, with Nox2 NADPH oxidase-derived superoxide reported to play a key role. The aim of this study was to identify novel mechanisms underlying development of cardiac remodelling/dysfunction further to DOX-stimulated Nox2 activation., Experimental Approach: Nox2 -/- and wild-type (WT) littermate mice were administered DOX (12 mg·kg -1 over 3 weeks) prior to study at 4 weeks. Detailed mechanisms were investigated in murine HL-1 cardiomyocytes, employing a robust model of oxidative stress, gene silencing and pharmacological tools., Key Results: DOX-induced cardiac dysfunction, cardiomyocyte remodelling, superoxide production and apoptosis in WT mice were attenuated in Nox2 -/- mice. Transcriptional analysis of left ventricular tissue identified 152 differentially regulated genes (using adjusted P < 0.1) in DOX-treated Nox2 -/- versus WT mice, and network analysis highlighted 'Cell death and survival' as the biological function most significant to the dataset. The mitochondrial membrane protein, mitofusin-2 (Mfn2), appeared as a strong candidate, with increased expression (1.5-fold), confirmed by qPCR (1.3-fold), matching clear published evidence of promotion of cardiomyocyte cell death. In HL-1 cardiomyocytes, targeted siRNA knockdown of Nox2 decreased Mfn2 protein expression, but not vice versa. While inhibition of Nox2 activity along with DOX treatment attenuated its apoptotic and cytotoxic effects, reduced apoptosis after Mfn2 silencing reflected a sustained cytotoxic response and reduced cell viability., Conclusions and Implications: DOX-induced and Nox2-mediated up-regulation of Mfn2, rather than contributing to cardiomyocyte dysfunction through apoptotic pathways, appears to promote a protective mechanism., Linked Articles: This article is part of a themed section on New Insights into Cardiotoxicity Caused by Chemotherapeutic Agents. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.21/issuetoc., (© 2017 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

Purpose: Endothelial nitric oxide synthase (eNOS)-derived nitric oxide (NO) has important vasoprotective functions that are compromised in the vasodegenerative phase of retinopathy of prematurity, owing to hyperoxia-induced depletion of the essential NOS cofactor BH4. Because modulating eNOS function can be beneficial or detrimental, our aim was to investigate the effect of BH4 supplementation on eNOS function and vascular regression in hyperoxia., Methods: Endothelial-specific eNOS-green fluorescent protein (GFP) overexpressing mice at postnatal day 7 (P7) were exposed to hyperoxia for 48 hours in the presence or absence of supplemental BH4, achieved by administration of sepiapterin, a stable BH4 precursor. Tissue was collected either for retinal flat mounts that were stained with lectin to determine the extent of vessel coverage or for analysis of BH4 by high-performance liquid chromatography, nitrotyrosine (NT) marker by Western blotting, VEGF expression by ELISA, and NOS activity by arginine-to-citrulline conversion. Primary retinal microvascular endothelial cells (RMEC) were similarly treated, and hyperoxia-induced damage was determined., Results: Sepiapterin effectively enhanced BH4 levels in hyperoxia-exposed retinas and brains, elevated NOS activity, and reduced NT-modified protein, leading to reversal of the exacerbated vasoregression observed in the presence of eNOS overexpression. In RMECs, hyperoxia-mediated depletion of BH4 dysregulated the redox balance by reducing nitrite and elevating superoxide and impaired proliferative ability. BH4 supplementation restored normal RMEC proliferation in vitro and also in vivo, providing a mechanistic link with the enhanced vascular coverage in eNOS-GFP retinas., Conclusions: These results demonstrate that BH4 supplementation corrects hyperoxia-induced RMEC dysfunction and preserves vascular integrity by enhancing eNOS function.

Background: Glucagon-like peptide-1 (GLP-1) therapies are routinely used for glycaemic control in diabetes and their emerging cardiovascular actions have been a major recent research focus. In addition to GLP-1 receptor activation, the metabolically-inactive breakdown product, GLP-1(9-36)amide, also appears to exert notable cardiovascular effects, including protection against acute cardiac ischaemia. Here, we specifically studied the influence of GLP-1(9-36)amide on chronic post-myocardial infarction (MI) remodelling, which is a major driver of heart failure progression., Methods: Adult female C57BL/6 J mice were subjected to permanent coronary artery ligation or sham surgery prior to continuous infusion with GLP-1(9-36)amide or vehicle control for 4 weeks., Results: Infarct size was similar between groups with no effect of GLP-1(9-36)amide on MI-induced cardiac hypertrophy, although modest reduction of in vitro phenylephrine-induced H9c2 cardiomyoblast hypertrophy was observed. Whilst echocardiographic systolic dysfunction post-MI remained unchanged, diastolic dysfunction (decreased mitral valve E/A ratio, increased E wave deceleration rate) was improved by GLP-1(9-36)amide treatment. This was associated with modulation of genes related to extracellular matrix turnover (MMP-2, MMP-9, TIMP-2), although interstitial fibrosis and pro-fibrotic gene expression were unaltered by GLP-1(9-36)amide. Cardiac macrophage infiltration was also reduced by GLP-1(9-36)amide together with pro-inflammatory cytokine expression (IL-1β, IL-6, MCP-1), whilst in vitro studies using RAW264.7 macrophages revealed global potentiation of basal pro-inflammatory and tissue protective cytokines (e.g. IL-1β, TNF-α, IL-10, Fizz1) in the presence of GLP-1(9-36)amide versus exendin-4., Conclusions: These data suggest that GLP-1(9-36)amide confers selective protection against post-MI remodelling via preferential preservation of diastolic function, most likely due to modulation of infiltrating macrophages, indicating that this often overlooked GLP-1 breakdown product may exert significant actions in this setting which should be considered in the context of GLP-1 therapy in patients with cardiovascular disease.

Retinopathy of prematurity is a sight-threatening complication of premature birth caused by nitro-oxidative insult to the developing retinal vasculature during therapeutic hyperoxia exposure and later ischemia-induced neovascularization on supplemental oxygen withdrawal. In the vasodegenerative phase, during hyperoxia, defective endothelial nitric oxide synthase (NOS) produces reactive oxygen and nitrogen free radicals rather than vasoprotective nitric oxide for unclear reasons. Crucially, normal NOS function depends on availability of the cofactor (6R)-5,6,7,8-tetrahydrobiopterin (BH4). Because BH4 synthesis is controlled enzymatically by GTP cyclohydrolase (GTPCH), we used GTPCH-depleted mice [hyperphenylalaninemia strain (hph1)] to investigate the impact of hyperoxia on BH4 bioavailability and retinal vascular pathology in the neonate. Hyperoxia decreased BH4 in retinas, lungs, and aortas in all experimental groups, resulting in a dose-dependent decrease in NOS activity and, in the wild-type group, elevated NOS-derived superoxide. Retinal dopamine levels were similarly diminished, consistent with the dependence of tyrosine hydroxylase on BH4. Despite greater depletion of BH4, the hph(+/-) and hph1(-/-) groups did not show exacerbated hyperoxia-induced vessel closure, but exhibited greater vascular protection and reduced progression to neovascular disease. This vasoprotective effect was independent of enhanced circulating vascular endothelial growth factor (VEGF), which was reduced by hyperoxia, but to local retinal ganglion cell layer-derived VEGF. In conclusion, a constitutively higher level of VEGF expression associated with retinal development protects GTPCH-deficient neonates from oxygen-induced vascular damage., (Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Adult bed bugs were exposed to the sublethal temperatures 34.0°C, 35.5°C, 37.0°C, 38.5°C, or 40.0°C for 3, 6, or 9 days. The two uppermost temperatures induced 100% mortality within 9 and 2 days, respectively, whereas 34.0°C had no observable effect. The intermediate temperatures interacted with time to induce a limited level of mortality but had distinct effects on fecundity, reflected by decreases in the number of eggs produced and hatching success. Adult fecundity remained low for up to 40 days after heat exposure, and the time until fertility was restored correlated with the temperature-sum experienced during heat exposure. Three or 6 days of parental exposure to 38.5°C significantly lowered their offspring's feeding and moulting ability, which consequently led to a failure to continue beyond the third instar. Eggs that were deposited at 22.0°C before being exposed to 37.0°C for 3 or 6 days died, whereas eggs that were exposed to lower temperatures were not significantly affected. Eggs that were deposited during heat treatment exhibited high levels of mortality also at 34.0°C and 35.5°C. The observed negative effects of temperatures between 34.0°C and 40.0°C may be utilized in pest management, and sublethal temperature exposure ought to be further investigated as an additional tool to decimate or potentially eradicate bed bug populations. The effect of parental heat exposure on progeny demonstrates the importance of including maternal considerations when studying bed bug environmental stress reactions.

Objectives: Raised plasma homocysteine is a risk factor for cardiovascular disease (CVD). Cysteine has also been associated with CVD risk. In this study, we investigated the association between known CVD risk factors, dietary factors, and total plasma cysteine, cysteinyl-glycine, and homocysteine., Methods: The study group was 765 male workers aged between 30-49 years. The dietary habits of the subjects were recorded using a food frequency questionnaire. Body mass index (BMI), smoking status, and blood pressure were assessed, and fasting blood samples were taken for analysis of serum concentrations of vitamins, lipids, total plasma cysteine, cysteinyl-glycine, and homocysteine, and genotyping for the methylenetetrahydrofolate reductase (MTHFR) polymorphism., Results: In multivariable analyses, cysteine was significantly positively associated with age and negatively associated with serum vitamin B12 and serum vitamin B6, while cysteinyl-glycine was significantly positively associated with BMI. Homocysteine (tHcy) was significantly negatively associated with serum folate, serum vitamin B12, and fruit and vegetable intake, and also depended on the MTHFR 677C>T genotype., Conclusions: Our data show a significant relationship between age, serum levels of B-vitamins and cysteine, and BMI and cysteinyl-glycine. In agreement with other studies, we also confirm an association between tHcy, serum folate and vitamin B12, MTHFR genotype, and fruit and vegetable intake. Further investigation into the role of these thiols and their determinants in CVD is required.