A novel assay of excess plasma kallikrein-kinin system activation in hereditary angioedema.

Background: Cleaved high-molecular-weight kininogen (HKa) is a disease state biomarker of kallikrein-kinin system (KKS) activation in patients with hereditary angioedema due to C1 inhibitor deficiency (HAE-C1INH), the endogenous inhibitor of plasma kallikrein (PKa). Objective: Develop an HKa-specific enzyme-linked immunosorbent assay (ELISA) to monitor KKS activation in the plasma of HAE-C1INH patients. Methods: A novel HKa-specific antibody was discovered by antibody phage display and used as a capture reagent to develop an HKa-specific ELISA. Results: Specific HKa detection following KKS activation was observed in plasma from healthy controls but not in prekallikrein-, high-molecular-weight kininogen-, or coagulation factor XII (FXII)-deficient plasma. HKa levels in plasma collected from HAE-C1INH patients in a disease quiescent state were higher than in plasma from healthy controls and increased further in HAE-C1INH plasma collected during an angioedema attack. The specificity of the assay for PKa-mediated HKa generation in minimally diluted plasma activated with exogenous FXIIa was demonstrated using a specific monoclonal antibody inhibitor (lanadelumab, IC50 = 0.044 µM). Conclusions: An ELISA was developed for the specific and quantitative detection of HKa in human plasma to support HAE-C1INH drug development. Improved quantification of the HKa biomarker may facilitate further pathophysiologic insight into HAE-C1INH and other diseases mediated by a dysregulated KKS and may enable the design of highly potent inhibitors targeting this pathway.

Exercise and cardiac rehabilitation in hypertensive patients with heart failure with preserved ejection fraction: A position statement on behalf of the Working Group of Arterial Hypertension of the Hellenic Society of Cardiology.

Arterial hypertension is a major cause of cardiovascular morbidity and mortality and the most common cause of comorbidity in heart failure (HF) with preserved ejection fraction (HFpEF). As an adjunct to medication, healthy lifestyle modifications with emphasis on regular exercise are strongly recommended by both the hypertension and the HF guidelines of the European Society of Cardiology. Several long-term studies have shown that exercise is associated with a reduction in all-cause mortality, a favorable cardiac and metabolic risk profile, mental health, and other non-cardiovascular benefits, as well as an improvement in overall quality of life. However, the instructions for the prescriptive or recommended exercise in hypertensive patients and, more specifically, in those with HFpEF are not well defined. Moreover, the evidence is based on observational or small randomized studies, while well-designed clinical trials are lacking. Despite the proven benefit and the guidelines' recommendations, exercise programs and cardiac rehabilitation in patients with hypertensive heart disease and HFpEF are grossly underutilized. This position statement provides a general framework for exercise and exercise-based rehabilitation in patients with hypertension and HFpEF, guides clinicians' rehabilitation strategies, and facilitates clinical practice. It has been endorsed by the Working Group of Arterial Hypertension of the Hellenic Society of Cardiology and is focused on the Health Care System in Greece.

Histopathological lesions of Actinobacillus pleuropneumoniae serotype 8 in infected pigs.

This study aimed to report, for the first time, histopathological lesions caused by an outbreak of acute Actinobacillus pleuropneumoniae serotype 8 infections in two farms in Cyprus. Lung tissue samples were collected from two different affected farms (a total of eight samples) for bacterial culture, multiplex polymerase chain reaction (PCR)-based serotyping and histopathological evaluation. Severe respiratory clinical signs, vomiting, anorexia, sudden deaths, a morbidity rate of around 25.00% and a mortality rate of over 60.00% in the fattening stage were reported. Macroscopic lesions included acute to subacute fibrotic, hemorrhagic and necrotizing pneumonia with occasionally encapsulated nodule-like abscesses and fibrous pleuritis. Histopathological evaluation revealed fibrous exudate between alveolar spaces and connective tissue, areas of necrosis mixed with alveolar macrophages, lymphocytes, plasma cells and necrotic leukocytes surrounding colonies of cocci. The bronchial and bronchiolar epithelia were degenerated and replaced by eosinophilic cell debris mixed with inflammatory cells. Several arteries and capillaries were clotted and/or infiltrated by inflammatory cells. In conclusion, these A. pleuropneumoniae serotype 8 cases were accompanied by acute illness, death and more pronounced bronchitis and bronchiolitis.

Histopathological Pulmonary Lesions in 1st-Day Newborn Piglets Derived from PRRSV-1 MLV Vaccinated Sows at the Last Stage of Gestation.

Modified live virus (MLV) vaccines for the control of porcine respiratory and reproductive syndrome virus (PRRSV) have been associated with the vertical and horizontal transmission of vaccine viruses. The present study aimed to describe pathological lung lesions in piglets born by gilts vaccinated with PRRSV-1 MLV. In total, 25 gilts were vaccinated at late gestation (100th day) and were divided into five groups according to the different vaccines (Vac) used: no vaccine-control group, Vac-1-strain DV, Vac-2-strain VP-046 BIS, Vac-3-strain 94881, Vac-4-strain 96V198. Within the first 0-9 h of the farrowing, blood samples were collected from all newborn piglets and lung samples were exanimated grossly, histopathologically and with scanning electron microscopy. PRRSV (RT-PCR-positive) and antibodies were detected in the serum of piglets from gilts vaccinated with Vac-2. In these piglets, moderate to severe interstitial pneumonia with thickened alveolar septa was noticed. Type II pneumocyte hyperplasia was also observed. The rest of the trial piglets showed unremarkable lung lesions. Phylogenetic analysis revealed the 98.7% similarity of the PRRSV field strain (GR 2019-1) to the PRRS MLV vaccine strain VP-046 BIS. In conclusion, the Vac-2 PRRSV vaccine strain can act as an infectious strain when vaccination is administrated at late gestation, causing lung lesions.

The COVID-19 pandemic as inspiration to reconsider epidemic models: A novel approach to spatially homogeneous epidemic spread modeling.

Epidemic spread models are useful tools to study the spread and the effectiveness of the interventions at a population level, to an epidemic. The workhorse of spatially homogeneous class models is the SIR-type ones comprising ordinary differential equations for the unknown state variables. The transition between different states is expressed through rate functions. Inspired by -but not restricted to- features of the COVID-19 pandemic, a new framework for modeling a disease spread is proposed. The main concept refers to the assignment of properties to each individual person as regards his response to the disease. A multidimensional distribution of these properties represents the whole population. The temporal evolution of this distribution is the only dependent variable of the problem. All other variables can be extracted by post-processing of this distribution. It is noteworthy that the new concept allows an improved consideration of vaccination modeling because it recognizes vaccination as a modifier of individuals response to the disease and not as a means for individuals to totally defeat the disease. At the heart of the new approach is an infection age model engaging a sharp cut-off. This model is analyzed in detail, and it is shown to admit self-similar solutions. A hierarchy of models based on the new approach, from a generalized one to a specific one with three dominant properties, is derived. The latter is implemented as an example and indicative results are presented and discussed. It appears that the new framework is general and versatile enough to simulate disease spread processes and to predict the evolution of several variables of the population during this spread.

SARS-CoV-2 wastewater monitoring using a novel PCR-based method rapidly captured the Delta-to-Omicron ΒΑ.1 transition patterns in the absence of conventional surveillance evidence.

Conventional SARS-CoV-2 surveillance based on genotyping of clinical samples is characterized by challenges related to the available sequencing capacity, population sampling methodologies, and is time, labor, and resource-demanding. Wastewater-based variant surveillance constitutes a valuable supplementary practice, since it does not require extensive sampling, and provides information on virus prevalence in a timely and cost-effective manner. Consequently, we developed a sensitive real-time RT-PCR-based approach that exclusively amplifies and quantifies SARS-CoV-2 genomic regions carrying the S:Δ69/70 deletion, indicative of the Omicron BA.1 variant, in wastewater. The method was incorporated in the analysis of composite daily samples taken from the main Wastewater Treatment Plant of Thessaloniki, Greece, from 1 December 2021. The applicability of the methodology is dependent on the epidemiological situation. During Omicron BA.1 global emergence, Thessaloniki was experiencing a massive epidemic wave attributed solely to the Delta variant, according to genomic surveillance data. Since Delta does not possess the S:Δ69/70, the emergence of Omicron BA.1 could be monitored via the described methodology. Omicron BA.1 was detected in sewage samples on 19 December 2021 and a rapid increase of its viral load was observed in the following 10-day period, with an estimated early doubling time of 1.86 days. The proportion of the total SARS-CoV-2 load attributed to BA.1 reached 91.09 % on 7 January, revealing a fast Delta-to-Omicron transition pattern. The detection of Omicron BA.1 subclade in wastewater preceded the outburst of reported (presumable) Omicron cases in the city by approximately 7 days. The proposed wastewater surveillance approach based on selective PCR amplification of a genomic region carrying a deletion signature enabled rapid, real-time data acquisition on Omicron BA.1 prevalence and dynamics during the slow remission of the Delta wave. Timely provision of these results to State authorities readily influences the decision-making process for targeted public health interventions, including control measures, awareness, and preparedness.

Detecting SARS-CoV-2 lineages and mutational load in municipal wastewater and a use-case in the metropolitan area of Thessaloniki, Greece.

The COVID-19 pandemic represents an unprecedented global crisis necessitating novel approaches for, amongst others, early detection of emerging variants relating to the evolution and spread of the virus. Recently, the detection of SARS-CoV-2 RNA in wastewater has emerged as a useful tool to monitor the prevalence of the virus in the community. Here, we propose a novel methodology, called lineagespot, for the monitoring of mutations and the detection of SARS-CoV-2 lineages in wastewater samples using next-generation sequencing (NGS). Our proposed method was tested and evaluated using NGS data produced by the sequencing of 14 wastewater samples from the municipality of Thessaloniki, Greece, covering a 6-month period. The results showed the presence of SARS-CoV-2 variants in wastewater data. lineagespot was able to record the evolution and rapid domination of the Alpha variant (B.1.1.7) in the community, and allowed the correlation between the mutations evident through our approach and the mutations observed in patients from the same area and time periods. lineagespot is an open-source tool, implemented in R, and is freely available on GitHub and registered on bio.tools.

Age-Dependent Invasion of Pseudorabies Virus into Porcine Central Nervous System via Maxillary Nerve.

Pseudorabies virus (PRV) is the causative agent for Aujeszky's disease, a disease that mainly affects pigs and incidentally other domestic and wild animals. While PRV is almost always fatal, causing neurological disease independently of the age in non-porcine species, the development of neurological manifestation in its host species, the pig, highly depends on the age. In this study, an attempt was made to investigate the effect of nerve development on the outcome of virus infection and the effect of virus infection on the structure of nerves in piglets of various ages. For that reason, 42 pigs at the age of one (n = 14), three (n = 14) and five (n = 14) weeks were inoculated with 107 TCID50 of PRV Kaplan strain and euthanized at one- or four-days post inoculation (DPI). The tissues of the trigeminal nervous pathway were collected and examined for virus replication (titration) in cell cultures for nerve morphology by light and transmission electron microscopy, and for viral antigen visualization by immunohistochemistry. The results showed that as the age of the pig increases, virus titers and clinical manifestations reduced, while, at the same time, myelin and axon development ceased. Following infection, the nerve structure was disrupted at all ages examined, being more prominent in one-week-old pigs compared to five-week-old pigs. In conclusion, the age-dependent PRV neuroinvasion in pigs seems to correlate with the morphological changes of neurons.

Administration of a Multi-Genus Synbiotic to Broilers: Effects on Gut Health, Microbial Composition and Performance.

In recent years, the applicability of prebiotics, probiotics and their mixtures, defined as synbiotics, in poultry production has received considerable attention. Following the increasing regulation of antibiotic use, these nutraceuticals are seen as an alternative way to sustain production efficiency and resistance to pathogens and stressors by modulating birds' gut health. The aim of this study was to evaluate the benefits provided under field conditions by administering the multi-species synbiotic PoultryStar® sol to broilers in drinking water. To this purpose, three Ross 308 broiler flocks, representing separate progenies of a breeder flock which was treated with the same synbiotic, were housed in separate farms, divided into treatment and control groups, and followed throughout the productive cycle. Synbiotic administration was shown to improve gut health even in absence of a challenge, with limited changes in terms of macroscopic intestinal lesions and more overt differences related to histopathological scores and villi length. Synbiotic-fed chickens performed consistently better in terms of body weight gain, feed conversion ratio and survivability. Lastly, the evaluation of the caecal microbiome through next-generation sequencing highlighted the effects of synbiotic supplementation on the composition of the bacterial population, the implications of which will, however, require further studies to be better comprehended.

SARS-CoV-2 adsorption on suspended solids along a sewerage network: mathematical model formulation, sensitivity analysis, and parametric study.

Accounting for SARS-CoV-2 adsorption on solids suspended in wastewater is a necessary step towards the reliable estimation of virus shedding rate in a sewerage system, based on measurements performed at a terminal collection station, i.e., at the entrance of a wastewater treatment plant. This concept is extended herein to include several measurement stations across a city to enable the estimation of spatial distribution of virus shedding rate. This study presents a pioneer general model describing the most relevant physicochemical phenomena with a special effort to reduce the complicated algebra. This is performed both in the topology regime, introducing a discrete-continuous approach, and in the domain of independent variables, introducing a monodisperse moment method to reduce the dimensionality of the resulting population balance equations. The resulting simplified model consists of a large system of ordinary differential equations. A sensitivity analysis is performed with respect to some key parameters for a single pipe topology. Specific numerical techniques are employed for the integration of the model. Finally, a parametric case study for an indicative-yet realistic-sewerage piping system is performed to show how the model is applied to SARS-CoV-2 adsorption on wastewater solids in the presence of other competing species. This is the first model of this kind appearing in scientific literature and a first step towards setting up an inverse problem to assess the spatial distribution of virus shedding rate based on its concentration in wastewater.

Inhibition versus activation of canonical Wnt-signaling, to promote chondrogenic differentiation of Mesenchymal Stem Cells. A review.

Canonical Wnt signaling regulation is essential for controlling stemness and differentiation of mesenchymal stem cells (MSCs). However, the mechanism through which canonical Wnt-dependent MSC lineage commitment leads to chondrogenesis is controversial. Some studies hypothesize that inhibition of canonical Wnt signaling induces MSC chondrogenic differentiation, while others support that the pathway should be activated to achieve MSC chondrogenesis. The purpose of the present review is to analyze data from recent studies to elucidate parameters regarding the role of canonical Wnt signaling in MSC chondrogenic differentiation.

The association of air pollutants exposure with subclinical inflammation and carotid atherosclerosis.

BACKGROUND: Air pollution is a well-described environmental factor with evidence suggesting a firm association with cardiovascular diseases. The purpose of this study was to determine the association of exposure to gaseous air pollutants on atherosclerosis burden. METHODS: 1955 inhabitants of the Corinthia region, aged 40 years or older, underwent clinical and biochemical assessment as well as carotid ultrasonography to evaluate carotid intima-media thickness (cIMT) and plaque burden. Analyzers recording time series concentration of CO, NO2, and SO2 were located at 4 different open sites (Regions 1, 2, 3 and 4) based on their proximity to industries, highways or shipyards. RESULTS: A higher concentration of CO, NO2, and SO2 was observed in Region 4 compared to the other regions. Mean cIMT (Region 1: 0.93 ± 0.24 mm; Region 2: 0.96 ± 0.40 mm; Region 3: 0.94 ± 0.39 mm; Region 4: 1.14 ± 0.55 mm, p < 0.001), maximum cIMT (p < 0.001) as well as carotid plaque burden (Region 1: 13.3%; Region 2: 18.8%; Region 3: 22.4%; Region 4: 38.6%, p < 0.001) were significantly higher in individuals of Region 4. Inhabitants of Region 4 had also higher levels of C reactive protein (Region 1: 4.56 ± 4.85 mg/l; Region 2: 3.49 ± 4.46 mg/l; Region 3: 4.03 ± 3.32 mg/l, Region 4: 5.16 ± 8.26 mg/l, p < 0.001). Propensity score analysis revealed higher inter-area differences in mean cIMT of individuals with coronary artery disease (CAD) (high vs low air pollution area: 1.56 ± 0.80 mm; vs. 1.18 ± 0.54 mm, p < 0.001) while there was no difference in cIMT of the matched population without CAD (p = 0.52). CONCLUSIONS: An increased carotid atherosclerotic and inflammatory burden is observed in inhabitants of areas with the highest concentration of air pollutants.

Evaluation of Clinical and Histological Outcomes of Adipose-Derived Mesenchymal Stem Cells in a Rabbit Corneal Alkali Burn Model.

To assess effects of adipose-derived mesenchymal stem cells (AMSCs) in corneal alkali injuries in an experimental animal model. Twenty white New Zealand rabbits were included in the study. The animal models were randomly divided into 2 groups. Rabbits in the AMSC group (n = 10) received an intrastromal, a subconjunctival injection, and topical instillation of 0.5 ml totally of phosphate-buffered saline (PBS) containing 2 × 106 AMSCs. In the control group (n = 10), rabbits received only 0.5 ml of PBS using the same methods. A masked investigator measured the corneal sensation, anterior chamber Inflammation (ACI), and conjunctival congestion. Additionally, a blind histological and immunohistochemical evaluation was made. In the AMSC group, the central corneal sensation was increased whereas ACI and conjunctival congestion were reduced compared to the control group in the 28 days of follow-up (p < 0.05). A statistically significant difference (p < 0.05) was noted between the two groups as recorded in the above parameters. Histological analysis showed that pathological vascularization was markedly reduced in the AMSC group which was consistent with the absence of factor VIII in the immunohistochemistry sections. There is a trend towards improved clinical outcomes including corneal sensation as well as acceleration in the restoration of normal corneal architecture in corneal alkali burns treated with AMSCs, results that support the need for further research in the field.

Does Vitamin D affects changes in volumetric bone mineral density and architecture in postmenopausal women after conservatively treated distal radius fractures?

OBJECTIVE: We examined the role of vitamin D on volumetric bone mineral density (vBMD) and architecture during the first week's post-fracture in postmenopausal women (PMW) with distal radial fractures (DRF) treated conservatively using peripheral Quantitative Computed Tomography (pQCT). METHODS: Patients were classified into 2 groups according to initial median 25(OH)D level; Group A (25(OH)D ≥15 ng/ml) and group B (25(OH)D <15 ng/ml). All patients were followed for 12 weeks at three visits: baseline, 6 weeks and 12 weeks post fracture. pQCT was performed at baseline in fractured and contralateral non-fractured radius and at 6th and 12th week on the fractured side. RESULTS: 39 patients completed the protocol. Mean 25(OH)D levels were 15.60±7.35 ng/ml (3.5-41.7). Trabecular (trab) bone mineral content (BMC) and trabvBMD increased at 6 wk. vs. baseline (p<0.001). Cortical BMC, cortvBMD and cross- sectional area (CSA) progressively decreased (p<0.001) during the 12 weeks. There was no interaction between baseline 25(OH)D levels and changes in trabecular and cortical BMC, vBMD and CSA. Advanced age and higher CTX and P1NP were associated with higher cortical bone loss. CONCLUSION: Vitamin D deficiency does not affect the early architectural changes after a DRF. Advanced age and higher bone remodeling were associated with higher cortical bone loss, probably related to immobilization and independent of vitamin D levels.

Evaluation of Femoral Bone Fracture Healing in Rats by the Modal Damping Factor and Its Correlation With Peripheral Quantitative Computed Tomography.

Introduction Monitoring the progress of fracture healing is essential in order to establish the appropriate timing that ensures adequate bone strength for weight-bearing. In the present experimental study on a rat model of femoral fracture healing, the measurement of bone density and strength by peripheral quantitative computerized tomography (pQCT) was correlated with the modal damping factor (MDF) method. Methods Four groups of 12 male six-month-old Wistar rats each were anesthetized and submitted to baseline femoral pQCT and MDF scanning, followed by aseptic midshaft osteotomy of the right femur which was fixed by a locking intramedullary nail technique. The animals were left to recover and re-scanned following euthanasia of each group after six, eight, 10, and 12 weeks, respectively. The parameters measured by the pQCT method were total bone mineral density (BMD) and polar strength strain index (SSIp). Results Fracture healing progressed over time and at 12 weeks post-osteotomy there was no statistically significant difference between the osteotomized right and the control left femurs regarding MDF, BMD, and SSIp measurements. The highest correlations for the osteotomized femurs were observed between MDF and BMD (r = -0.647, P = 0.043), and between MDF and SSIp (r = -0.350, P = 0.321), at 10 weeks postoperatively. The high to moderate correlations between MDF and BMD, and between MDF and SSIp respectively, support the validity of MDF in assessing fracture healing. Conclusions Based on our findings in this fracture healing animal model, the results from the MDF method are reliable and correlate highly with the total BMD and moderately with the SSI polar values obtained by the pQCT method of bone quality measurement. Further studies are needed which may additionally support that the MDF method can be an attractive portable alternative to monitor fracture healing in the community.

Exposure Biomarkers and Histopathological Analysis in Pig Liver After Exposure to Mycotoxins Under Field Conditions: Special Report on Fumonisin B1.

Liver samples from finisher pigs were collected at the slaughterhouses for the analysis of zearalenone (ZEA), alfa-/beta-zearalenone (α-ZE, ß-ZE), zearalanone (ZA), alfa-/beta-ZA (α-ZA, ß-ZA), aflatoxin B1 (AFB1) and aflatoxin M1, fumonisin B1 (FB1), ochratoxin A (OTA) and ochratoxin B, deoxynivalenol and deepoxi-deoxynivalenol (DOM-1). For the analysis liquid chromatography-triple quadrupole coupled with mass spectrometry was applied. Liver samples with detected FB1 were further histopathologically evaluated after hematoxylin and eosin staining. Various levels of liver mycotoxins were detected in all farms. Pig livers with 2.91-8.30 µg/kg of FB1 were detected in three farms, estimate of 850-2400 µg/kg of FB1 intake, whereas 0.54 µg/kg of OTA was detected in one farm, estimate of 75 µg/kg of OTA intake. Moreover, pig livers with 0.30 µg/kg of ZEA, 1.87 µg/kg of α-ZE, and 0.63 µg/kg of ß-ZE were detected in one farm, estimate with of 300 µg/kg of ZEA intake. The histopathological analysis revealed that the lesions' grading and necrosis grading were analogously increased when FB1 concentration increased from 2.91 to 4.36-8.30 µg/kg. The severity of megalocytosis was analogously increased with FB1 detection levels and particularly in levels of 4.36-8.3 µg/kg. However, the increased FB1 detection levels did not show analogous behavior with the severity of hepatic cell vacuolization. Results showed that FB1 remained the most critical risk factor in the Greek pig industry, whereas ZEA and AFB1 were also prevalent. The OTA contamination in pig farms raised a high risk for animal and human health.

Quantitative proteomics of cerebrospinal fluid using tandem mass tags in dogs with recurrent epileptic seizures.

This prospective study included four dog groups (group A: healthy dogs, groups B: dogs with idiopathic epilepsy under antiepileptic medication (AEM), C: idiopathic epilepsy dogs without AEM administration, D: dogs with structural epilepsy). The purpose of the study was to compare the proteomic profile among the four groups. Samples were analyzed by a quantitative Tandem Mass Tags approach using a Q-Exactive-Plus mass-spectrometer. Identification and relative quantification were performed using Proteome Discoverer, and data were analyzed using R. Gene ontology terms were analyzed based on Canis lupus familiaris database. Data are available via ProteomeXchange with identifier PXD018893. Eighteen proteins were statistically significant among the four groups (P < 0.05). MMP2 and EFEMP2 appeared down-regulated whereas HP and APO-A1 were up-regulated (groups B, D). CLEC3B and PEBP4 were up-regulated whereas APO-A1 was down-regulated (group C). IGLL1 was down-regulated (groups B, C) and up-regulated (group D). EFEMP2 was the only protein detected among the four groups and PEBP4 was significantly different among the epileptic dogs. Western blot and SPARCL immunoassay were used to quantify HP abundance change, validating proteomic analysis. Both, showed good correlation with HP levels identified through proteomic analysis (r = 0.712 and r = 0.703, respectively). SIGNIFICANCE: The proteomic analysis from CSF of dogs with epileptic seizures could reflect that MMP2, HP and APO-A1 may contribute to a blood-brain barrier disruption through the seizure-induced inflammatory process in the brain. MMP2 change may indicate the activation of protective mechanisms within the brain tissue. Antiepileptic medication could influence several cellular responses and alter the CSF proteome composition.

The international initiatives of the collaboration between the Aristotle University of Thessaloniki School of Medicine, the Panhellenic Medical Association and the World Psychiatric Association, concerning mental health during the COVID-19 outbreak.

During the coronavirus disease 2019 (COVID-19) pandemic, all European countries were hit, but mortality rates were heterogenous, with some countries being hit very hard, while others including Greece had a much lower death rate during the first wave of spring 2020. The ultra-fast application of measures was probably the reason of this outstanding success. This outbreak is expected to trigger feelings of fear, worry, and stress, as responses to an extreme threat for the community and the individual. In addition, changes in social behavior, as well as in working conditions, daily habits and routine, are expected to impose further stress, especially with the expectation of an upcoming economic crisis and possible unemployment. In Greece, where the lockdown was extremely successful in terms of containing the outbreak, worries concerning the possible adverse effects on mental health were also predominant. A collaboration concerning mental health during the COVID-19 outbreak was established, between the Aristotle University School of Medicine, the Panhellenic Medical Association and the World Psychiatric Association. Two large multinational studies were launched, one concerning the general population and one university students. Students' mental health is an area of special interest, both because of the vulnerability of this age group as well as because any disruption during the time of the studies has profound long-term consequences in the lives of the individuals, and this might trigger feelings of fear, worry, and stress. According the results from the Greek arm of the students' study, during the lockdown, two-thirds of university students reported at least 'much' increase in anxiety, one third in depressive feelings and in 2.59% concerning suicidal thoughts. There was also a worsening of quality of life and deterioration of lifestyle issues. Major depression was present in 12.43% with an additional 13.46% experiencing severe distress. Beliefs in conspiracy theories enjoyed wide acceptance ranging from 20-68%, with students of law, literature, pedagogics, political sciences and related studies manifesting higher acceptance rates. Female sex and depression/dysphoria both independently but also in interaction were related to higher rates of such beliefs. The results of the Greek arm of the general population study suggested that during the lockdown, clinical depression was present in 9.31%, with an additional 8.5% experiencing severe distress. Increased anxious and depressive emotions (including subclinical cases) were present in more than 40% of the population. In persons with a previous history of depression, 23.31% experienced depression vs. 8.96% of cases without previous history, who were experiencing their first depressive episode. Family dynamics suggested that fewer conflicts and better quality of relationships were surprisingly related to higher anxiety and depressive emotions, higher rates of depression and distress, and greater rates of suicidal thoughts. Eventually, spiritual and religious affiliation could protect the individual from the emerging suicidal thoughts. As correlation does not imply causation, the results suggest that conspiracy theories could be either the cause of depression or on the contrary a coping mechanism against depression. After taking into consideration that also in the family environment the expression of anger seemed to be a protective factor, the most likely explanation could be that the beliefs in conspiracy theories are a coping and 'protective' mechanism against the emergence of depression. These studies were among the first published, they went deeper in the data collection and even led to the creation of a model with distinct stages for the development of mental disorders during the lockdown. The analysis of the international data will probably provide further insight into the prevalence of mental disorders and the universal but also culturally specific models and factors pertaining to their development. At the time this editorial was in press, more than 40 countries representing more than two thirds of earth's population were participating with more than 45,000 responses already gathered.

Histopathological Lesions Accompanied with First-Time Isolation of a PRRSV-2 Strain in Greece.

Genotype 2 strains of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV-2) have been reported sporadically in Europe. Even if, PRRSV-2 reported to be genetically homogenous in Europe due to the introduction of an MLV vaccine strain, independent introductions of PRRSV-2 field strains have been reported. The aim of the present study was to report the complete genome sequence and evaluate the histopathological lesions of a PRRSV-2 strain, isolated for the first time in Greece. During a routine blood sampling in a commercial pig farm, the results revealed positive samples in weaners of 40-60 days for the PRRSV-2, using real-time polymerase chain reaction. The clinical picture was characterized from respiratory symptoms in weaners, as well as coughing and poor performance at finishing stage and less than 3% mortality rate from weaning stage to finishing stage. The use of ORF5 for PRRSV phylogenetic analysis of the isolated PRRSV strain, named "x1544-1 strain", was successfully determined, belonging to the genotype PRRSV-2. Comparison of the obtained sequence revealed nucleotide sequence identity >98% with PRRSV-2 strain VR2332 and other related strains from Denmark and China. The histopathological evaluation revealed diffuse interstitial pneumonia, multifocal interstitial nephritis, while in the lymphoid organs, follicular and paracortical hyperplasia, coexisting with necrosis and depletion of germ cells were detected. The results of current study undersign the importance for veterinary practitioners to have up-to-date access to phylogenetic data linked to phenotypic information to follow-up the control and prevention strategies against PRRSV.