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Zinc is an essential trace element that is involved in many biological processes and in cellular homeostasis. In pancreatic β-cells, zinc is crucial for the synthesis, processing, and secretion of insulin, which plays a key role in glucose homeostasis and which deficiency is the cause of diabetes. The accumulation of zinc in pancreatic cells is regulated by the solute carrier transporter SLC30A8 (or Zinc Transporter 8, ZnT8), which transports zinc from cytoplasm in intracellular vesicles. Allelic variants of SLC30A8 gene have been linked to diabetes. Given the physiological intracellular localization of SLC30A8 in pancreatic β-cells and the ubiquitous endogenous expression of other Zinc transporters in different cell lines that could be used as cellular model for SLC30A8 recombinant over-expression, it is challenging to develop a functional assay to measure SLC30A8 activity. To achieve this goal, we have firstly generated a HEK293 cell line stably overexpressing SLC30A8, where the over-expression favors the partial localization of SLC30A8 on the plasma membrane. Then, we used the combination of this cell model, commercial FluoZin-3 cell permeant zinc dye and live cell imaging approach to follow zinc flux across SLC30A8 over-expressed on plasma membrane, thus developing a novel functional imaging- based assay specific for SLC30A8. Our novel approach can be further explored and optimized, paving the way for future small molecule medium-throughput screening.

This work presents the materials selection process, the design and the dimensioning process of a latent heat storage tank that works between a high temperature heat pump and an Organic Rankine Cycle unit. The selected heat storage material is the S117 Phase Change Material that has a melting point at 117°C matches the operational temperature of the system at approximately 120°C. The tank configuration is selected for optimised heat transfer process, resulted from practical experience of the project partners and it is described in details in the document. The simulation results from the Computational Fluid Dynamic study of the tank are also presented here. This work should be useful for engineers designing compact heat storage tanks for medium temperature applications.

Placental insufficiency and gestational diabetes, which are both serious pregnancy complications, are linked to altered fetal growth, whether restricted or excessive, and result in metabolic dysfunction, hypoxic/oxidative injury, and adverse perinatal outcomes. Although much research has been carried out in this field, the underlying pathogenetic mechanisms have not as yet been fully elucidated. Particularly because of the role it plays in cardiovascular performance, glucose metabolism, inflammation, and oxidative stress, the adipokine apelin was recently shown to be a potential regulator of fetal growth and metabolic programming. This review investigated the numerous biological actions of apelin in utero and aimed to shed more light on its role in fetal growth and metabolic programming. The expression of the apelinergic system in a number of tissues indicates its involvement in many physiological mechanisms, including angiogenesis, cell proliferation, energy metabolism, inflammation, and oxidative stress. Moreover, it appears that apelin has a major function in disorders such as diabetes mellitus, fetal growth abnormalities, fetal hypoxia, and preeclampsia. We herein describe in detail the regulatory effects exerted by the adipokine apelin on fetal growth and metabolic programming while stressing the necessity for additional research into the therapeutic potential of apelin and its mechanisms of action in pregnancy-related disorders.

This work provides the policy and economic analysis of the renewable heating and cooling sector in Greece. The novelty of this study is that it unveils the different policy instruments and incentive structures in promoting renewable heating and cooling adoption, and it analyses the social, cultural and technical barriers to the adoption of renewable heating and cooling systems in Greece. To this end, a PESTEL (Political, Economic, Social, Technical, Environmental and Legal) analysis is performed, with a view to demonstrating the factors that affect Greece’s progress against the National Energy and Climate Plans (NECP), the decarbonisation of the heating and cooling sector and finally, the alignment with the long-term energy strategy. Overall, the results of this analysis show that the heating and cooling sector is still greatly dependent on the use of fossil fuels. However, there are more opportunities than barriers for the deployment of the renewable heating and cooling sector in Greece; opportunities arise from the ambitious political goals that are harmonized with those of the EU, targeting climate-neutrality by 2050.

The rate of ocean uptake of anthropogenic CO2 has declined over the past decade, so a critical question for science and policy is whether the ocean will continue to act as a sink. Large areas of the ocean remain without observations for carbonate system variables, and oceanic CO2 observations have declined since 2017. The Mediterranean Sea is one such an area, especially its eastern part, where there is a paucity of carbonate system data, with large areas not sampled or only sampled by ship-based discrete measurements as opposed to high frequency, sensor-equipped time-series fixed stations. The aim of this study was to analyze a multi-year time-series of high-frequency (hourly) partial pressure CO2 (pCO2) and pH measurements in the Eastern Mediterranean, along with low-frequency (monthly) measurements of total dissolved inorganic carbon and total alkalinity. The pCO2 time-series was the first obtained in the Eastern Mediterranean. The study was conducted at a fixed platform of the POSEIDON system (Heraklion Coastal Buoy) located near Crete Island. Temperature was the dominant factor controlling the temporal variability of pCO2 and pH, while the remaining non-thermal variability appeared to be related to evaporation, water mixing, and biological remineralization-production. The air-sea CO2 fluxes indicated a transition from a winter-spring sink period to a summer-autumn source period. The annual air-sea CO2 flux was too low (-0.16 ± 0.02 mol m-2 yr-1) and variable to conclusively characterize the area as a net source or sink of CO2, highlighting the need for additional high frequency observation sites. Algorithms were developed using temperature, chlorophyll and salinity data to estimate pCO2 and total alkalinity, in an effort to provide tools for estimates in poorly observed areas/periods from remotely sensed products. The applicability of the algorithms was tested using Surface Ocean CO2 Atlas (SOCAT) data from the Eastern Mediterranean Sea (1999 to 2020) which showed that the algorithm pCO2 estimates were generally within ±20 μatm of the pCO2 values reported by SOCAT. Finally, the integration and analysis of the data provided directions on how to optimize the observing strategy, by readapting sensor location and using estimation algorithms with remote sensing data.

Background: Polycystic ovary syndrome (PCOS) is closely related to various adverse cardiovascular manifestations and increased cardiovascular risk. However, atrial fibrillation (AF) development and atrial conduction abnormalities have not been thoroughly studied in patients with PCOS. Methods: This meta-analysis (CRD42021261375) was conducted in accordance with the PRISMA guidelines. Our aim was to investigate associations between PCOS and disorders in atrial conduction parameters linked with an increased risk for AF occurrence. Results: Five cohort studies with aggregate data on 406 adult women (229 with PCOS and 177 age-matched without PCOS) were included in this analysis. Our results showed a significantly increased mean difference in P-wave maximum duration (+7.63 ± 7.07 msec; p < 0.01) and P-wave dispersion (+11.42 ± 5.22 msec; p = 0.03) of patients with PCOS compared to healthy women. The mean difference in P-wave minimum duration (−2.22 ± 2.68 msec; p = 0.11) did not reach the statistical threshold between the compared groups. Echocardiographic measurements of atrial electromechanical delay (AED) also indicated a statistically significant mean difference in favour of the PCOS group in all assessed parameters, except for atrial electromechanical coupling (PA) in the tricuspid annulus. Particularly, PCOS was associated with increased lateral PA, septal PA, inter- and intra-AED durations (mean difference: +17.31 ± 9.02 msec; p < 0.01, +11.63 ± 7.42 msec; p < 0.01, +15.31 ± 9.18 msec; p < 0.01, +9.31 ± 6.85 msec; p < 0.01, respectively). Conclusions: PCOS is strongly associated with alterations in several electrocardiographic and echocardiographic parameters indicating abnormal atrial conduction. Therefore, PCOS could be considered as a causal or triggering factor of AF. Larger studies are needed to confirm these results and investigate direct associations between PCOS and AF.

Abstract Background Pleiotropy describes the phenomenon in which a gene affects multiple phenotypes. The extent of pleiotropy is still disputed, mainly because of issues of inadequate power of analyses. A further challenge is that empirical tests of pleiotropy are restricted to a small subset of all possible phenotypes. To overcome these limitations, we propose a new measurement of pleiotropy that integrates across many phenotypes and multiple generations to improve power. Results We infer pleiotropy from the fitness cost imposed by frequency changes of pleiotropic loci. Mixing Drosophila simulans populations, which adapted independently to the same new environment using different sets of genes, we show that the adaptive frequency changes have been accompanied by measurable fitness costs. Conclusions Unlike previous studies characterizing the molecular basis of pleiotropy, we show that many loci, each of weak effect, contribute to genome-wide pleiotropy. We propose that the costs of pleiotropy are reduced by the modular architecture of gene expression, which facilitates adaptive gene expression changes with low impact on other functions.

The effect of specific design characteristics of the SRTA collector are discussed, such as the absorber diameter, the absorber length and the optical error from the tracking mechanism. It is found that the reduction of the absorber’s length by 29.6% leads to the reduction of the optical efficiency by about 13.7%. Increasing the absorber’s diameter is found to increase the optical efficiency, but only for diameters up to 0.05 m; further increase is found to have a negligible effect on the optical efficiency. The geometry of the studied collector is found to retain its high optical efficiency for optical errors up to 0.2o, but for higher optical errors lower efficiency is observed. This study shows that the SRTA solar concentrator can operate efficiently under a wide range of conditions and provides an insight for the design engineers of concentrated solar collectors.

Placental insufficiency and gestational diabetes, which are both serious pregnancy complications, are linked to altered fetal growth, whether restricted or excessive, and result in metabolic dysfunction, hypoxic/oxidative injury, and adverse perinatal outcomes. Although much research has been carried out in this field, the underlying pathogenetic mechanisms have not as yet been fully elucidated. Particularly because of the role it plays in cardiovascular performance, glucose metabolism, inflammation, and oxidative stress, the adipokine apelin was recently shown to be a potential regulator of fetal growth and metabolic programming. This review investigated the numerous biological actions of apelin in utero and aimed to shed more light on its role in fetal growth and metabolic programming. The expression of the apelinergic system in a number of tissues indicates its involvement in many physiological mechanisms, including angiogenesis, cell proliferation, energy metabolism, inflammation, and oxidative stress. Moreover, it appears that apelin has a major function in disorders such as diabetes mellitus, fetal growth abnormalities, fetal hypoxia, and preeclampsia. We herein describe in detail the regulatory effects exerted by the adipokine apelin on fetal growth and metabolic programming while stressing the necessity for additional research into the therapeutic potential of apelin and its mechanisms of action in pregnancy-related disorders. [ABSTRACT FROM AUTHOR]

Male factors may be present in up to 50–70% of infertile couples and the prevalence of male infertility accounts for 20–30% of infertility cases. Understanding the mechanisms and causes behind male infertility remains a challenge, but new diagnostic tools such as DNA fragmentation might aid in cases where the routine semen analysis is insufficient. DNA fragmentation, which refers to damages or breaks of the genetic material of the spermatozoa, is considered one of the main causes of male infertility due to impaired functional capability of sperm. The aim of the present narrative review is to investigate and enlighten the potential correlation between DNA fragmentation and male infertility parameters such as the seminal profile and the reproductive outcomes. Comprehensive research in PubMed/Medline and Scopus databases was conducted and 28 studies were included in the present review. Fourteen studies provided data regarding the impact of DNA fragmentation and seminal parameters and showed a correlation of significantly lower sperm count, lower concentration, motility, and abnormal morphology with an increased DNA fragmentation index (DFI). Similarly, 15 studies provided data regarding the impact of DFI on reproductive outcomes. Two studies showed higher aneuploidy rates with higher DFI values, and seven studies showed significantly lower pregnancy rates and live birth rates with higher DFI values. Ultimately, the studies included in this review highlight, collectively, the importance of measuring sperm DFI in the assessment of male infertility. Further studies are needed to explore the effectiveness of interventions aiming to reduce DFI levels. [ABSTRACT FROM AUTHOR]

This work provides the policy and economic analysis of the renewable heating and cooling sector in Greece. The novelty of this study is that it unveils the different policy instruments and incentive structures in promoting renewable heating and cooling adoption, and it analyses the social, cultural and technical barriers to the adoption of renewable heating and cooling systems in Greece. To this end, a PESTEL (Political, Economic, Social, Technical, Environmental and Legal) analysis is performed, with a view to demonstrating the factors that affect Greece's progress against the National Energy and Climate Plans (NECP), the decarbonisation of the heating and cooling sector and finally, the alignment with the long-term energy strategy. Overall, the results of this analysis show that the heating and cooling sector is still greatly dependent on the use of fossil fuels. However, there are more opportunities than barriers for the deployment of the renewable heating and cooling sector in Greece; opportunities arise from the ambitious political goals that are harmonized with those of the EU, targeting climate-neutrality by 2050. [ABSTRACT FROM AUTHOR]

Alport syndrome (AS) is a hereditary glomerulopathy due to pathogenic variants in COL4A3, COL4A4, and COL4A5. Treatment with Renin–Angiotensin–Aldosterone System (RAAS) inhibitors can delay progression to end stage renal disease (ESRD). From 2018 until today, we performed Whole Exome Sequencing (WES) in 19 patients with AS phenotype with or without positive family history. Fourteen of these patients were children. Genetic testing was extended to family members at risk. All patients received a genetic diagnosis of AS: five X-linked AS (XLAS) males, five X-linked AS (XLAS) females, six autosomal dominant AS (ADAS), and one autosomal recessive AS (ARAS). After cascade screening four XLAS males and eight XLAS females, six ADAS and three ARAS heterozygotes were added to our initial results. Fifteen patients were eligible to start treatment with RAAS inhibitors after their diagnosis. All XLAS female patients, ARAS heterozygotes, and ADAS have been advised to be followed up, so that therapeutic intervention can begin in the presence of microalbuminuria. Genetic diagnosis of AS ensures early therapeutic intervention and appropriate follow up to delay progression to chronic kidney disease, especially in thet pediatric population. [ABSTRACT FROM AUTHOR]

Excitatory amino acid transporters (EAAT/SLC1) mediate Na+-dependent uptake of extracellular glutamate and are potential drug targets for neurological disorders. Conventional methods to assess glutamate transport in vitro are based on radiolabels, fluorescent dyes or electrophysiology, which potentially compromise the cell’s physiology and are generally less suited for primary drug screens. Here, we describe a novel label-free method to assess human EAAT function in living cells, i.e., without the use of chemical modifications to the substrate or cellular environment. In adherent HEK293 cells overexpressing EAAT1, stimulation with glutamate or aspartate induced cell spreading, which was detected in real-time using an impedance-based biosensor. This change in cell morphology was prevented in the presence of the Na+/K+-ATPase inhibitor ouabain and EAAT inhibitors, which suggests the substrate-induced response was ion-dependent and transporter-specific. A mechanistic explanation for the phenotypic response was substantiated by actin cytoskeleton remodeling and changes in the intracellular levels of the osmolyte taurine, which suggests that the response involves cell swelling. In addition, substrate-induced cellular responses were observed for cells expressing other EAAT subtypes, as well as in a breast cancer cell line (MDA-MB-468) with endogenous EAAT1 expression. These findings allowed the development of a label-free high-throughput screening assay, which could be beneficial in early drug discovery for EAATs and holds potential for the study of other transport proteins that modulate cell shape.

Objective: Blood transfusion is a common lifesaving treatment but it is often complicated with alloimmunization. Previously studies in Greece have concentrated on alloimmunization in multiply transfused thalassemic patients or antenatal women. However, the relative frequency of red blood cell (RBC) alloantibodies in the general patient population has not been studied so far. The aim of the present retrospective study was to estimate the prevalence and specificity of RBC alloantibodies in a large cohort of patients in two general hospitals and their association with age, sex, and the patients' clinic of hospitalization. Materials and Methods: Data from 2012 to 2016 from the 'Sismanogleio' and 'Thriasio' general hospitals in Athens, Greece, were studied retrospectively. Statistical analysis was performed with SAS for Windows 9.4. Results: Six hundred twenty-six patients (626/53800, 1.16%) were alloimmunized for one or more alloantibodies. The mean age was 67.99+-17.56 years. Most antibodies were found in women [62.66% (438/699) in women vs. 37.34% (261/699) in men (p=0.0007)], while the vast majority of antibodies (66.81%) were found in patients aged 61-90. The most frequent antibody was anti-Kell (26.61%), followed by anti-E (16.02%), anti-D (15.02%), anti-Jka (5.87%), and anti-M (5.72%). Anti-C (81.48%, n=27) and anti-Cw (54.17%, n=24) tended to be found more often in patients with multiple antibodies. Most alloimmunized cases were found in general surgery (42.65%) and internal medicine departments (38.66%). Conclusion: According to our results, the alloimmunization data in a general patient population in Greece were consistent with the majority of studies in the international literature. Whether a strategy at national level needs to be directed towards extending matching for the whole population or towards applying sensitive and compulsory indirect antiglobulin tests before any transfusions in order to efficiently prevent alloimmunization remains an issue of debate.

Advanced marine observation infrastructures are the most significant scientific tool for the study of marine ecosystem trends and shifts. Ocean monitoring technologies, though highly demanding and expensive, are essential for the monitoring and long-term study of oceanic systems. The POSEIDON system for monitoring and forecasting the marine environment is an augmented research infrastructure, unique in the Eastern Mediterranean basin, contributing to the European Ocean Observing System implementation, focusing—among others—on biogeochemical observations and deep-sea ecosystem and geological processes. The technological evolution of the POSEIDON system through a science-coupled strategy supported by engineers and scientists, resulted in a state-of-the-art ocean observing system. There has been a continuous expansion of the infrastructure with new scientific platforms and supporting facilities. Innovative sensing technologies were introduced in the operational data acquisition and new methodologies and tools were developed to improve the system operations and efficiency. As a part of the scientific community of ocean observatories, POSEIDON contributes actively to the improving of the ocean observing. International access to engineering and field demonstrating services, data products and technology testing facilities has been offered to scientists and industry partners. POSEIDON is a widely recognizable international technology testing/demonstrating node specializing in marine technology providing high-level services.

Diminished ovarian reserve (DOR) is associated with a reduced quantity and quality of the retrieved oocytes, usually leading to poor reproductive outcomes which remain a great challenge for assisted reproduction technology (ART). Women with DOR often have to seek for oocyte donation, precluding genetically related offspring. Germline nuclear transfer (NT) is a novel technology in ART that involves the transfer of the nuclear genome from an affected oocyte/zygote of the patient to the cytoplast of an enucleated donor oocyte/zygote. Therefore, it offers opportunities for the generation of genetically related embryos. Currently, although NT is clinically applied only in women with serious mitochondrial DNA disorders, this technology has also been proposed to overcome certain forms of female infertility, such as advanced maternal age and embryo developmental arrest. In this review, we are proposing the NT technology as a future treatment option for DOR patients. Strikingly, the application of different NT strategies will result in an increase of the total number of available reconstituted embryos for DOR patients.

Research infrastructures have been established throughout Europe in order to create robust organizations that will facilitate and enhance research and innovation processes and will advance society with innovative products and services. The Hellenic Integrated Marine Observing, Forecasting and Technology System (component of HIMIOFoTS RI) has been implemented in the framework of the National Roadmap for Research Infrastructures to form a large-scale infrastructure for the marine environment in Greece. It links together ocean observing and forecasting systems, coastal zone monitoring and management practices, as well as ocean engineering testing facilities. The overarching framework of the system supports the coordination of five organizations with expertise in the field of marine science and technology, the central management of research activities, and the common development of services and products. It comprises facilities and resources while it provides open access to research communities (academia, industry) to support the scientific advancements and innovation in their fields. The Hellenic Marine Observing, Forecasting and Technology System was further enhanced during its implementation through significant upgrades and developments in order to extend its observing capacity and the forecasting and technological abilities, while advancing the provided services and products.

There is a general scarcity of oceanic observations that concurrently examine air–sea interactions, coastal–open-ocean processes and physical–biogeochemical processes, in appropriate spatiotemporal scales and under continuous, long-term data acquisition schemes. In the Mediterranean Sea, the resulting knowledge gaps and observing challenges increase due to its oligotrophic character, especially in the eastern part of the basin. The oligotrophic open Cretan Sea's biogeochemistry is considered to be representative of a greater Mediterranean area up to 106 km2, and understanding its features may be useful on even larger oceanic scales, since the Mediterranean Sea has been considered a miniature model of the global ocean. The spatiotemporal coverage of biogeochemical (BGC) observations in the Cretan Sea has progressively increased over the last decades, especially since the creation of the POSEIDON observing system, which has adopted a multiplatform, multivariable approach, supporting BGC data acquisition. The current POSEIDON system's status includes open and coastal sea fixed platforms, a Ferrybox (FB) system and Bio-Argo autonomous floats that remotely deliver fluorescence as a proxy of chlorophyll-a (Chl-a), O2, pH and pCO2 data, as well as BGC-related physical variables. Since 2010, the list has been further expanded to other BGC (nutrients, vertical particulate matter fluxes), ecosystem and biodiversity (from viruses up to zooplankton) variables, thanks to the addition of sediment traps, frequent research vessel (R/V) visits for seawater–plankton sampling and an acoustic Doppler current profiler (ADCP) delivering information on macrozooplankton–micronekton vertical migration (in the epipelagic to mesopelagic layer). Gliders and drifters are the new (currently under integration to the existing system) platforms, supporting BGC monitoring. Land-based facilities, such as data centres, technical support infrastructure, calibration laboratory and mesocosms, support and give added value to the observatory. The data gathered from these platforms are used to improve the quality of the BGC-ecosystem model predictions, which have recently incorporated atmospheric nutrient deposition processes and assimilation of satellite Chl-a data. Besides addressing open scientific questions at regional and international levels, examples of which are presented, the observatory provides user-oriented services to marine policy makers and the society, and is a technological test bed for new and/or cost-efficient BGC sensor technology and marine equipment. It is part of European and international observing programs, playing a key role in regional data handling and participating in harmonization and best practices procedures. Future expansion plans consider the evolving scientific and society priorities, balanced with sustainable management.