Transcriptomics of prion diseases

Despite substantial research aiming to elucidate prion disease pathogenesis, the underlying mechanisms of cellular toxicity and neurodegeneration remain poorly characterized. The human brain comprises numerous cell populations with a heterogeneous transcriptional landscape, complicating the interpretation of transcriptomic studies. To untangle this complexity, we first established and validated two single-nucleus sequencing methodologies and a bioinformatics pipeline for data analysis. We then designed a time-course case-control study of RML- and control brain homogenate-inoculated FVB mice (N = 95, time points: 20, 40, 80, 120 dpi and disease end-stage), and a human case-control study in post-mortem and biopsied brain samples (N = 26) and applied our transcriptomics pipeline. We generated 210,000 high-quality cell transcriptomes across 5 time points in mice and identified 26 subclusters of cortical neurons, interneurons, mature oligodendrocytes, oligodendrocyte precursor cells, vascular and leptomeningeal cells, and astrocytes. Glial activation was evident from 80 dpi, while our data suggested a selective transcriptomic response of individual cell clusters to disease. We identified a pattern of neuronal transcriptomic change shortly after RML-brain inoculation that quickly resolved, despite rapidly increasing prion titres in the brain, only to return at later stages when the neuropathology of prion disease was evident. Subsequent pathway analyses identified common perturbed biological pathways associated with synaptic dysfunction and ion homeostasis. Our human tissue samples did not pass quality control criteria, highlighting the need for different methodologies to assay archived samples. Here we provide the first single-cell transcriptomics study of prion diseases in mouse which found cell-type and time-specific patterns. Taken together, findings suggest that prion replication itself does not produce a transcriptomic signature in the brain, rather, a transient pattern of toxicity can be seen immediately following inoculation of prion disease brain homogenate, which becomes re-established as prion disease neuropathology develops

Evaluation of e-banking dimensions by Greek customers

The use of electronic banking is increased rapidly worldwide. However, the percentage of Greek e-banking users, even if it has increased, is still very low. The adoption of e-banking depends on some factors which are connected with the services that the banks offer and the satisfaction from these factors influences, the overall satisfaction. The aim of this study was the exploration of the perception of Greek e-banking users about the factors affecting the satisfaction from the use of e-banking and moreover the influence of their experiences in the perception’s formation. In order to achieve the aims of this study a research was realized, using a structured questionnaire, in 354 users of e-banking. The results show that Greek customers are quite satisfied from the e-banking dimensions and moreover the dimensions that mostly affect the overall satisfaction are “trust” and “convenience/ usefulness”.peer-reviewe

PROFITABILITY OF CONSTRUCTING SECTOR AND HOW MARKET STRUCTURE, COST STRUCTURE AND CONCENTRATION AFFECT IT: THE CASE OF GREECE

Abstract This study considers market structure, cost structure and concentration and examines which of these factors affect the profitability of construction firms in Greece

Prion protein gene mutation detection using long-read Nanopore sequencing

Prion diseases are fatal neurodegenerative conditions that affect humans and animals. Rapid and accurate sequencing of the prion gene PRNP is paramount to human prion disease diagnosis and for animal surveillance programmes. Current methods for PRNP genotyping involve sequencing of small fragments within the protein-coding region. The contribution of variants in the non-coding regions of PRNP including large structural changes is poorly understood. Here, we used long-range PCR and Nanopore sequencing to sequence the full length of PRNP, including its regulatory region, in 25 samples from blood and brain of individuals with inherited or sporadic prion diseases. Nanopore sequencing detected the same variants as identified by Sanger sequencing, including repeat expansions/deletions. Nanopore identified additional single-nucleotide variants in the non-coding regions of PRNP, but no novel structural variants were discovered. Finally, we explored somatic mosaicism of PRNP's octapeptide repeat region, which is a hypothetical cause of sporadic prion disease. While we found changes consistent with somatic mutations, we demonstrate that they may have been generated by the PCR. Our study illustrates the accuracy of Nanopore sequencing for rapid and field prion disease diagnosis and highlights the need for single-molecule sequencing methods for the detection of somatic mutations

Orexin-A exerts equivocal role in atherosclerosis process depending on the duration of exposure : in vitro study

Orexin-A is a peptide hormone that plays a crucial role in feeding regulation and energy homeostasis. Diurnal intermittent fasting (DIF) has been found to increase orexin-A plasma levels during fasting hours, while Ramadan fasting which resembles DIF, has led to beneficial effects on endothelial function. Herein, we aimed to investigate the effects of orexin-A on the expression of molecules involved in the atherogenesis process: Monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9) and tissue inhibitor of metalloproteinase-1 and 2 (TIMP-1 and TIMP-2), in human aortic endothelial cells (HAECs). HAECs were incubated with orexin-A at concentrations of 40 ng/mL, 200 ng/mL and 400 ng/mL for 6, 12 and 24 h. The mRNA levels of MCP-1, MMP-2, MMP-9, TIMP-1, and TIMP-2 and orexin-1 receptor were measured by real-time qPCR. We also evaluated the MMP-2, p38, phospho-p38, NF-κΒ/p65 as well as TIMP-1 protein levels by Western blot and ELISA, respectively. MMP-2 activity was measured by gelatin zymography. Short-term 6-h incubation of HAECs with orexin-A at a high concentration (400 ng/mL) decreased MCP-1, MMP-2 expression, MMP-2/TIMP-1 ratio (p < 0.05), and MMP-2 activity, while incubation for 24 h increased MCP-1, MMP-2 expression (p < 0.05), MMP-2/TIMP-1 and MMP-2/TIMP-2 ratio (p < 0.01 and p < 0.05, respectively) as well as MMP-2 activity. The dual effects of orexin-A are mediated, at least in part, via regulation of p38 and NF-κΒ pathway. Orexin-A may have an equivocal role in atherosclerosis process with its effects depending on the duration of exposure

acquiT he contribution of MR Urography in imaging congenital malformations in children - preliminary results

 Magnetic resonance urography (MRU) is a fairly new technique which has been studied for the last 10 years. MRU offers increased spatial and temporal resolution and provides quantitative functional information on renal perfusion, excretion and drainage. This article presents the first results obtained from MRU studies in children in Northern Greece. 21 children (3-11 years old) diagnosed with congenital malformations were studied with MRU. A standardized protocol was created in order to make MRU feasible in everyday use, based on protocols suggested by other researchers. Both T1 and T2 weighted images were obtained using the following sequences: 2D Τ2-weighted fat saturation, 3D single shot fast spin-echo (SSFSE/RARE), 2D Radial SSFSE and T1-weighted gradient LAVA (3D SPGR). In 16 out of the 21 cases the MRU images and data agreed with the previous diagnosis based on radionuclide and ultrasound studies. In 5 cases MRU provided additional information, altering or even overruling the previous diagnosis. These 5 cases are presented in this article

Panic Attack during Elective Gastrointestinal Endoscopy

Background. Esophagogastroduodenoscopy (EGD) and colonoscopy (CS) can evoke anxiety, embarrassment, and discomfort. These concerns can culminate in panic attacks, which may traumatize patients and significantly decrease their compliance to the procedure. The objective of this study was to evaluate the relationship between preendoscopic anxiety and the possibility of a panic attack during an elective gastrointestinal endoscopy (EGE). Methods. The study population comprised of 79 Greek outpatients. The examination was carried out without the use of conscious sedation. Patients' anxiety levels were assessed before the procedure using the Greek version of the Spielberger State-Trait Anxiety Inventory (STAI-Y). Results. Seventy-nine patients were enrolled: 45 EGD and 34 CS. Females had higher state and trait anxiety levels than males (48.14 ± 7.94 versus 44.17 ± 7.43, P < 0.05; and 43.68 ± 6.95 versus 39.86 ± 7.46, P < 0.05). Patients who experienced panic attack had significantly higher levels of both trait and state anxiety, compared to those who were panic-free. There was no significant relationship between panic attacks and sex or type of procedure. Conclusions. Patients who experience panic attacks during endoscopic procedures appear to have significantly higher anxiety levels before the procedure. Administering the STAI questionnaire prior to the endoscopy seems to be a useful screening method for vulnerable patients

Imaging of Left Main Coronary Artery; Untangling the Gordian Knot

Left Main Coronary Artery (LMCA) disease is considered a standout manifestation of coronary artery disease (CAD), because it is accompanied by the highest mortality. Increased mortality is expected, because LMCA is responsible for supplying up to 80% of total blood flow to the left ventricle in a right-dominant coronary system. Due to the significant progress of biomedical technology, the modern drug-eluting stents have remarkably improved the prognosis of patients with LMCA disease treated invasively. In fact, numerous randomized trials provided similar results in one- and five-year survival of patients treated with percutaneous coronary interventions (PCI) -guided with optimal imaging and coronary artery bypass surgery (CABG). However, interventional treatment requires optimal imaging of the LMCA disease, such as intravascular ultrasound (IVUS) and optical coherence tomography (OCT). The aim of this manuscript is to review the main pathophysiological characteristics, to present the imaging techniques of LMCA, and, last, to discuss the future directions in the depiction of LMCA disease.</p

Pinna nobilis in the Greek seas (NE Mediterranean): on the brink of extinction?

The Mediterranean endemic fan mussel Pinna nobilis is suffering an ongoing basin-scale mass mortality event (MME) since 2016. As most Mediterranean populations have collapsed, the species has been declared as Critically Endangered in the IUCN Red List of threatened species. In an effort to track the progress of the MME and provide updated information on the status of the species in the Greek seas, data collected through dedicated surveys and opportunistic assessments during 2019 and 2020 have been compiled. During surveys conducted at 258 sites, a total of 14,589 fan mussels were recorded, of which 81.1% were dead. Of the remaining 2,762 live individuals, 256 were juveniles. Two marine areas that still sustain living populations were identified, namely Kalloni Gulf (Lesvos Island), and Laganas Bay (Zakynthos Island). The inner part of Kalloni Gulf appears to maintain the largest surviving population of the species in the eastern Mediterranean, with an abundance estimate of 684,000 individuals (95% confidence interval: 322,000-1,453,000). Solitary, potentially resistant, scattered individuals were recorded at several sites. Other previously abundant populations that had been assessed in the past, specifically those of Lake Vouliagmeni (Korinthiakos Gulf), Souda Bay (Crete) and Gera Gulf (Lesvos Island) with a total of ~350,000 individuals, have now been wiped out. Our results document the collapse of most P. nobilis populations throughout the Greek seas. The MME has progressed substantially between early 2019 and mid-2020, as indicated by the increase in mortality at sites consecutively monitored multiple times. This work highlights the urgent need for continuous monitoring of surviving populations and calls for immediate implementation of an effective protection and management strategy that will ensure the persistence of surviving individuals and the production of resistant offspring