Oxygenation of European seabass (Dicentrarchus labrax L.) in cages through aeration and effect on lipid metabolism.

Two groups of the same batch of European seabass were used in an industrial-scale trial in sea cages in Vorios Evoikos, Greece. For about one month, one of the two cages was oxygenated by use of compressed air injected in seawater through an AirX frame (Oxyvision A/S, Norway) at 3.5 m depth, while oxygen concentration and temperature were monitored every 30 min. The liver, gut, and pyloric ceca samples were taken from fish of both groups for measurement of gene expression of phospholipase A2 (PLA2) and hormone-sensitive lipase (HSL), and for histological analysis at the middle and end of the experiment. Real-time qPCR was performed with housekeeping genes ACTb, L17, and EF1a. The expression of PLA2 increased in pyloric caeca samples from the oxygenated cage, suggesting that aeration improved the absorption rate of dietary phospholipids (p < 0.05). Expression of HSL increased significantly in liver samples from the control cage, in comparison with the aerated cage (p < 0.05). Histological examination of sea bass samples revealed an increased fat accumulation in the hepatocytes of fish in the oxygenated cage. The results of the present study showed increased lipolysis induced by low DO levels in farmed sea bass in cages.

Temperature-Biased miRNA Expression Patterns during European Sea Bass (Dicentrarchus labrax) Development.

Environmental effects and, particularly, temperature changes have been demonstrated to influence the activity, function, and well-being of teleosts. Temperature may change seasonally in the wild, and in captivity under aquaculture operations. Moreover, climate change is expected to shift temperature profiles worldwide. MicroRNAs (miRNA) are important temperature-sensitive gene-expression regulators acting at the post-transcriptional level. They are known to be key regulators in development, reproduction, and immune responses. Therefore, early larval development of the European sea bass (Dicentrarchus labrax), one of the most extensively cultured species in Mediterranean aquaculture, was investigated at early rearing temperatures, i.e., 15, 17.5, and 20 °C, in regard to the impact of temperatures on miRNAs through sncRNA high-throughput sequencing but also at the phenotypic level in terms of growth, sex, vision, and skeletal deformities. Expression profiling revealed stage- and temperature-specific miRNA expression targeting genes with roles in reproduction and immune response mainly at the flexion and all-fins stages. Similar stage- and temperature-specific results were also observed concerning the number of rod cells and lower jaw elongation. The present work presents for the first time highly promising results on the influence of early rearing temperature at the post-transcriptional level during European sea bass development, with a putative impact on reproduction and immune response, as well as regarding teleost vision and larval development.

Tailoring the Nonlinear Optical Response of Some Graphene Derivatives by Ultraviolet (UV) Irradiation.

In the present work the impact of in situ photoreduction, by means of ultraviolet (UV) irradiation, on the nonlinear optical response (NLO) of some graphene oxide (GO), fluorographene (GF), hydrogenated fluorographene (GFH) and graphene (G) dispersions is studied. In situ UV photoreduction allowed for the extended modification of the degree of functionalization (i.e., oxidization, fluorination and hydrogenation), leading to the effective tuning of the corresponding sp2/sp3 hybridization ratios. The nonlinear optical properties of the studied samples prior to and after UV irradiation were determined by means of the Z-scan technique using visible (532 nm), 4 ns laser excitation, and were found to change significantly. More specifically, while GO's nonlinear optical response increases with irradiation time, GF and GFH present a monotonic decrease. The graphene dispersions' nonlinear optical response remains unaffected after prolonged UV irradiation for more than an hour. The present findings demonstrate that UV photoreduction can be an effective and simple strategy for tuning the nonlinear optical response of these graphene derivatives in a controllable way, resulting in derivatives with custom-made responses, thus more suitable for different photonic and optoelectronic applications.

Enriched HeK4me3 marks at Pm-0 resistance-related genes prime courgette against Podosphaera xanthii.

Powdery mildew (PM) disease, caused by the obligate biotrophic fungal pathogen Podosphaera xanthii, is the most reported and destructive disease on cultivated Cucurbita species all over the world. Recently, the appearance of highly aggressive P. xanthii isolates has led to PM outbreaks even in resistant crops, making disease management a very difficult task. To challenge this, breeders rely on genetic characteristics for PM control. Analysis of commercially available intermediate resistance courgette (Cucurbita pepo L. var. cylindrica) varieties using cytological, molecular, and biochemical approaches showed that the plants were under a primed state and induced systemic acquired resistance (SAR) responses, exhibiting enhanced callose production, upregulation of salicylic acid (SA) defense signaling pathway genes, and accumulation of SA and defense metabolites. Additionally, the intermediate resistant varieties showed an altered epigenetic landscape in histone marks that affect transcriptional activation. We demonstrated that courgette plants had enriched H3K4me3 marks on SA-BINDING PROTEIN 2 and YODA (YDA) genes of the Pm-0 interval introgression, a genomic region that confers resistant to Cucurbits against P. xanthii. The open chromatin of SA-BINDING PROTEIN 2 and YDA genes was consistent with genes' differential expression, induced SA pathway, altered stomata characteristics, and activated SAR responses. These findings demonstrate that the altered epigenetic landscape of the intermediate resistant varieties modulates the activation of SA-BINDING PROTEIN 2 and YDA genes leading to induced gene transcription that primes courgette plants.

Joint ESH excellence centers' national meeting on renal sympathetic denervation: A Greek experts' survey.

OBJECTIVE: The efficacy of renal sympathetic denervation (RDN) has been affirmed by a number of recent clinical studies, despite controversies in this field over the last five years. Therefore, it is of paramount importance that hypertension experts debate the merits of RDN by revealing and expressing their personal beliefs and perspectives regarding this procedure. METHODS: A cross-sectional survey was conducted among Greek leaders of the Hypertension Excellence Centers with the use of a closed-type questionnaire specifically designed to elicit information and evaluate the respondent's views and perspectives about RDN efficacy, safety and ideal target patient population. RESULTS: A total of 36 participants completed the survey. Based on the results, RDN was considered efficient (91.7%) and safe (94.5%), while the overwhelming majority of the participants felt confident in the long-term efficacy (88.9%) of the intervention and that it lacks reliable predictors of blood pressure response (94.5%). Patients with resistant (91.7%), ultra-resistant (94.4%), and uncontrolled hypertension (80.6%) were suggested as ideal candidates for RDN. Establishing a close co-operation between interventionalists and hypertension experts was considered essential to ensure the efficacy (97.2%) as well as the safety (97.3%) of the procedure. CONCLUSION: The vast majority of Greek hypertension experts surveyed were convinced of the efficacy and safety of RDN based on the preponderance of available scientific and clinical data. Identification of the ideal patient group remains controversial. Respondents generally agreed on the necessity of building close collaborative relationships between interventionalists and hypertension experts in order to improve RDN clinical outcome.

Silicon Nanosheets versus Graphene Nanosheets: A Comparison of Their Nonlinear Optical Response.

Silicene, the silicon analogue of graphene, represents a new class of two-dimensional (2D) materials, which shares some of the outstanding physical properties of graphene. Furthermore, it has the advantage of being compatible with the current Si-based technology. However, this 2D material is not stable and is quite prone to oxidation. The hydride-terminated silicene, called silicane, is a more stable form of 2D silicon, if functionalized via, for example, the hydrosilylation reaction. In this work, the third-order nonlinear optical (NLO) properties of two functionalized silicanes, namely hydride-terminated silicon nanosheets (SiNS-H) and 1-dodecene-functionalized silicon nanosheets (SiNS-dodecene), are accessed and compared to those of single-layer graphene, under 35 ps, 532 and 1064 nm excitation. The present results show that the functionalized silicanes exhibit comparable and even higher NLO response than that of single-layer graphene, making them strong competitors of graphene and very interesting candidates for future photonic and optoelectronic applications.

Silicon Nanosheets: An Emerging 2D Photonic Material with a Large Transient Nonlinear Optical Response beyond Graphene.

The present work reports on the transient nonlinear optical (NLO) responses of two different types of 2D silicon nanosheets (SiNSs), namely hydride-terminated silicon nanosheets (SiNS-H) and 1-dodecene-functionalized silicon nanosheets (SiNS-dodecene). The main motivation of this study was to extend the knowledge regarding the NLO properties of these Si-based materials, for which very few published studies exist so far. For that purpose, the NLO responses of SiNS-H and SiNS-dodecene were investigated experimentally in the nanosecond regime at 532 and 1064 nm using the Z-scan technique, while the obtained results were compared to those of certain recently studied graphene nanosheets. SiNS-dodecene was found to exhibit the largest third-order susceptibility χ(3) values at both excitation wavelengths, most probably ascribed to the presence of point defects, indicating the importance of chemical functionalization for the efficient enhancement and tailoring of the NLO properties of these emerging 2D Si-based materials. Most importantly, the results demonstrated that the present silicon nanosheets revealed comparable and even larger NLO responses than graphene nanosheets. Undoubtedly, SiNSs could be strong competitors of graphene for applications in 2D-material-based photonics and optoelectronics.

Success Rate and Safety of Dental Implantology in Patients Treated With Antiresorptive Medication: A Systematic Review.

There is no agreement of data on the subject of implant failure and the development of osteonecrosis in patients receiving antiresorptive agents. The purpose of this systematic review is to evaluate whether dental implants placed in patients on antiresorptive medication have an increased failure rate and whether the implant placement or the implant existence are risk factors for developing medication-related osteonecrosis of the jaw (MRONJ). An electronic search was conducted in PubMed/Medline, and all publications fulfilling the inclusion criteria were included. The search was completed by a hand research of the references cited in all electronic identified publications, resulting in 411 articles. Based on the inclusion criteria, 32 studies were included, with a total of 5221 patients, 12 751 implants, 618 cases of implants loss, and 136 cases of MRONJ analyzed. Because of the small number of studies, most of which were characterized by a low level of quality, it cannot be established that the use of antiresorptive medication affects dental implant survival rates. The risk of MRONJ as an early or late complication is also not well established. Therefore, successful dental implant procedures in patients receiving antiresorptive medication might be possible, but more studies need to be carried out in the future to verify this topic. Apart from intravenous antiresorptive drugs, which remain an absolute contraindication, the use of antiresorptive medication is not a contraindication to dental implantology, but it must be accompanied by careful treatment planning, informing patients about possible complications, and essential long follow-up periods.

Enhancing and Tuning the Nonlinear Optical Response and Wavelength-Agile Strong Optical Limiting Action of N-octylamine Modified Fluorographenes.

Fluorographene has been recently shown to be a suitable platform for synthesizing numerous graphene derivatives with desired properties. In that respect, N-octylamine-modified fluorographenes with variable degrees of functionalization are studied and their nonlinear optical properties are assessed using 4 ns pulses. A very strong enhancement of the nonlinear optical response and a very efficient optical limiting action are observed, being strongly dependent on the degree of functionalization of fluorographene. The observed enhanced response is attributed to the increasing number of defects because of the incorporation of N-heteroatoms in the graphitic network upon functionalization with N-octylamine. The present work paves the way for the controlled covalent functionalization of graphene enabling a scalable access to a wide portfolio of graphene derivatives with custom-tailored properties.

Outstanding Broadband (532 nm to 2.2 µm) and Very Efficient Optical Limiting Performance of Some Defect-Engineered Graphenes.

Graphene derivatives and defect-engineered graphenes have attracted the interest of researchers owing to the excellent and tunable properties they exhibit. In this work the optical limiting performance of two defect-engineered boron- and nitrogen-doped reduced graphene oxides is investigated. Both graphenes are found to exhibit exceptional and broadband optical limiting action ranging from 532 to 2200 nm. Their optical limiting efficiency was found to be superior to that of all the other graphene derivatives studied to date, exhibiting a gradually decreasing optical limiting onset, reaching the record low value of ∼0.002 J cm-2 at 2200 nm. The results demonstrate the potential of engineering the defects of such reduced graphene oxides, resulting in very broadband and efficient optical limiting graphene derivatives, showing a promising method to further tailor their optical and optoelectronic properties.

The effect of vitamin K2 supplementation on vascular calcification in haemodialysis patients: a 1-year follow-up randomized trial.

PURPOSE: Vascular calcification (VC) is an independent risk factor for cardiovascular disease in hemodialysis patients while Matrix GLA protein (MGP) is one of the most potent inhibitors of VC and its activation is vitamin K dependent. The aim of this study is to investigate the role of oral vitamin K2 supplementation in the prevention of VC progression in haemodialysis patients. METHODS: We conducted a prospective randomized interventional study in patients on hemodialysis. Patients were randomly assigned to either receiving orally 200 µgr of vitamin K2 (vitamin K2/MK-7, Solgar) every day for 1 year or no treatment. Uncarboxylated MGP (uc-MGP) concentrations were quantified using ELISA at randomization, at 3 and at 12 months. Aortic calcification was evaluated using Agatston score after an abdominal computed tomography scan that was performed at the beginning and at 12 months of follow-up. RESULTS: There were 102 patients that were randomized. After 1 year of follow-up, 22 patients from the vitamin K2 group and 30 patients from the control group were included in the analysis. After 3 months of treatment, uc-MGP values remained unchanged in the vitK2 group but after 1 year were reduced by 47% (p = 0.005). Furthermore, uc-MGP at 1 year was increased by 12% in the control group. At 1 year, vitK2 group had significantly lower values of uc-MGP in comparison to controls (p = 0.03). Agatston score was increased significantly both in vitamin K2 and control group at 1 year with no difference between groups. CONCLUSIONS: Oral administration of vitamin K2 in patients on haemodialysis reduced serum uc-MGP levels but did not have an effect in the progression of aortic calcification.

Boron toxicity in higher plants: an update.

MAIN CONCLUSION: In this review, emphasis is given to the most recent updates about morpho-anatomical, physiological, biochemical and molecular responses adopted by plants to cope with B excess. Boron (B) is a unique micronutrient for plants given that the range of B concentration from its essentiality to toxicity is extremely narrow, and also because it occurs as an uncharged molecule (boric acid) which can pass lipid bilayers without any degree of controls, as occurs for other ionic nutrients. Boron frequently exceeds the plant's requirement in arid and semiarid environments due to poor drainage, and in agricultural soils close to coastal areas due to the intrusion of B-rich seawater in fresh aquifer or because of dispersion of seawater aerosol. Global releases of elemental B through weathering, volcanic and geothermal processes are also relevant in enriching B concentration in some areas. Considerable progress has been made in understanding how plants react to B toxicity and relevant efforts have been made to investigate: (I) B uptake and in planta partitioning, (II) physiological, biochemical, and molecular changes induced by B excess, with particular emphasis to the effects on the photosynthetic process, the B-triggered oxidative stress and responses of the antioxidant apparatus to B toxicity, and finally (III) mechanisms of B tolerance. Recent findings addressing the effects of B toxicity are reviewed here, intending to clarify the effect of B excess and to propose new perspectives aimed at driving future researches on the topic.

Thiophenol-Modified Fluorographene Derivatives for Nonlinear Optical Applications.

The synthesis and characterization of two thiophenol-modified fluorographene derivatives, namely methoxythiophenol-and dimethylaminothiophenol-modified fluorographenes, are reported, while their third-order nonlinear optical response were thoroughly investigated under both visible (532 nm) and infrared (1064 nm) with 35 ps and 4 ns laser pulses. The graphene derivatives were obtained by partial nucleophilic substitution/reduction of fluorographene by the corresponding organic thiophenols, and were fully characterized by techniques including infrared/Raman spectroscopy, X-ray photoelectron spectroscopy, atomic force spectroscopy, and high-resolution transmission microscopy. This type of modification resulted in graphenic structures where the attached thiol groups, sp2 domains, and the residual fluorine groups act as donors, π bridges, and acceptors, respectively. Both derivatives exhibited large nonlinear optical response compared to fluorographene, and have potential applications in optical limiting as an alternative to fullerenes.

Changes in sugar metabolism associated to stem bark thickening partially assist young tissues of Eriobotrya japonica seedlings under boron stress.

Boron (B) toxicity frequently affects plant performances and productivity, especially in arid and semi-arid environments. In this experiment, loquat seedlings were subjected to 25 µM (control) or 400 µM B (B excess) to test the hypothesis that (i) B alters sugar/polyol metabolism in polyol-producing tree species as loquat and (ii) changes of leaf and stem anatomy assist young tissues against toxic effect of B. Gas exchange was monitored from the beginning of the experiment (FBE) till one week after the first visible symptoms of B toxicity appeared in the upper part of the stems (147 d FBE). At 147 FBE, plant biometric parameters and pattern of B accumulation, leaf and stem anatomy, chlorophyll a fluorescence kinetics as well as biochemical measurements were assessed in top (asymptomatic) leaves and upper stem bark. Boron accumulated principally (in the row) in top leaves > top bark > top wood in B-stressed plants, but no changes in allocation pattern were found between controls and B-stressed plants. Excess B promoted the increase in the spongy layer of top leaves and caused the development of cork and numerous collenchyma cells with increased cell wall thickness. This mechanism, which has never been described before, can be considered an attempt to store excessive B in tissues where B ions are less harmful. The accumulation of sorbitol (B-complexing polyol) in top leaves and stem bark can be considered as a further attempt to detoxify B excess. However, B toxicity drastically affects the photosynthetic rate of top leaves, mainly due to non-stomatal limitations, i.e., reduction of ambient CO2 use efficiency and of photosystem II (PSII) efficiency, modification of the partitioning excess energy dissipation in PSII, thus leading to an increased level of lipid peroxidation. Our results suggest that changes in sugar metabolism associated with leaf and stem bark thickening partially assist (but not totally preserve) young tissues of loquat plants under B stress.

Cultivar-Dependent Responses of Eggplant (Solanum melongena L.) to Simultaneous Verticillium dahliae Infection and Drought.

Several studies regarding the imposition of stresses simultaneously in plants have shown that plant responses are different under individual and combined stress. Pathogen infection in combination with drought can act both additively and antagonistically, suggesting a tailored-made plant response to these stresses. The aforementioned combination of stresses can be considered as one of the most important factors affecting global crop production. In the present research we studied eggplant responses to simultaneous Verticillium dahliae infection and drought with respect to the application of the individual stresses alone and investigated the extent to which these responses were cultivar dependent. Two eggplant cultivars (Skoutari and EMI) with intermediate resistance to V. dahliae were subjected to combined stress for a 3-week period. Significant differences in plant growth, several physiological and biochemical parameters (photosynthesis rate, leaf gas exchanges, Malondialdehyde, Proline) and gene expression, were found between plants subjected to combined and individual stresses. Furthermore, plant growth and molecular (lipid peroxidation, hydrogen peroxide, gene expression levels) changes highlight a clear discrimination between the two cultivars in response to simultaneous V. dahliae infection and drought. Our results showed that combined stress affects significantly plants responses compared to the application of individual stresses alone and that these responses are cultivar dependent.

Experimental Study of the Structural Effect on the Nanosecond Nonlinear Optical Response of O-Doped Polycyclic Aromatic Hydrocarbons.

The nonlinear optical response of some O-doped polycyclic aromatic hydrocarbons (PAHs) is systematically investigated in the present work aiming to understand the influence of structural effects on their nonlinear optical response. In that view, the third-order nonlinear optical properties of these PAHs were measured under 4 ns visible (532 nm) and infrared (1064 nm) laser excitation. The O-doped PAHs were found to exhibit large saturable absorption and negative sign nonlinear refraction under visible excitation, increasing both with the addition of naphthalene units and with the number of O atoms. Their nonlinear optical response was found to be negligible under infrared excitation. Similar measurements performed on thin films of these PAHs have shown that they maintain their large nonlinear optical response even in the solid state, confirming their high potential for optoelectronic and photonic applications.

Changes in Arterial Stiffness and N-terminal pro-brain natriuretic peptide Levels after Endovascular Repair of Descending Thoracic Aorta.

BACKGROUND: Limited data exist concerning the biomechanical and central hemodynamic changes induced by endograft implantation in the descending thoracic aorta. The aim of this prospective ongoing study was to evaluate changes in arterial stiffness, assessed by pulse wave velocity (PWV; m/sec), and N-terminal pro-brain natriuretic peptide (NT-proBNP; pg/mL) levels in patients undergoing endovascular repair of descending thoracic aorta (thoracic endovascular aortic repair [TEVAR]). METHODS: Twenty-seven patients with thoracic aorta pathology who underwent elective TEVAR were included in the study. Blood samples were obtained preoperatively, 24 hr, 48 hr, and 6 months postoperatively, and serum levels of NT-proBNP were measured. PWV was determined before and 6 months after TEVAR. One-way analysis of variance by ranks was used to test the alterations in PWV (from baseline to 6 months) and NT-proBNP (along the 4 phases of evaluation). Post hoc analyses were appropriately performed. RESULTS: We recorded an increase in values of NT-proBNP from baseline (median = 96.1, interquartile range [IQR] = 82.7-117.9) to 24 hr postoperative (median = 201.6, IQR = 82.8-425.9), 48 hr postoperative (median = 317.0, IQR = 102.5-1,479.5), and 6 months postoperative (median = 144, IQR = 82.8-276.4). The Kruskal-Wallis H test showed a statistically significant increase (x2(3) = 11.17, P = 0.01) in NT-proBNP from baseline (rank mean = 22.19) toward the postoperative time points of evaluation (24 hr postoperative: 35.17 [change: +12.9, P = 0.02]; 48 hr postoperative: 42.64 [change: +20.5, P < 0.001]; 6 month postoperative: 34.91 [change: +12.7, P = 0.03]). An increase in PWV values was recorded from baseline (median = 11.9, IQR = 10.0-13.5) to 6 months postoperatively (median = 13.9, IQR = 11.9-16.4). That change achieved statistically significant level [x2(1) = 4.86, P = 0.03], with an increase in mean rank PWV (+7.5). CONCLUSIONS: Implementation of thoracic stent grafts may be associated with considerable increase of both arterial stiffness and NT-proBNP serum levels along time. Those results may indicate an adverse cardiac impact of TEVAR. However, the early and long-term effects of TEVAR on cardiovascular outcomes require further investigation.

Comparative Assessment of the Anticoagulant Activity of Rivaroxaban and Dabigatran in Patients With Nonvalvular Atrial Fibrillation: A Noninterventional Study.

There is a shortage of data in everyday clinical practice about the anticoagulant effects caused by the new oral anticoagulants (NOAs). Our aim was to estimate the intensity of anticoagulant activity induced by rivaroxaban 20 mg qd and dabigatran 110 mg bid among patients with nonvalvular atrial fibrillation (NV-AF).We studied 20 patients with NV-AF treated with dabigatran, and 20 patients treated with rivaroxaban. We performed conventional coagulation tests, thrombin generation (TG) test, thromboelastometry (ROTEM), and epinephrine-induced light transmission aggregometry (LTA) in all 40 patients and 20 controls. Hemoclot Thrombin Inhibitors (HTI) and Factor Xa Direct Inhibitor (DiXaI) assay were used to measure dabigatran and rivaroxaban plasma levels, respectively.Measurements of all assays estimating anticoagulant activity across the 2 patient groups were similar, except for aPTT. Patients on dabigatran exhibited statistically significantly prolonged aPTT values (P < 0.001). In LTA, patients on dabigatran also showed decreased aggregation compared to those on rivaroxaban (P = 0.045). Regarding the TG test, there was no association between endogenous thrombin potential (ETP) and rivaroxaban plasma levels (P = 0.33) as opposed to dabigatran levels (P < 0.001), but significant correlations were observed between rivaroxaban plasma concentrations and kinetic parameters of TG assay (Tlag, P = 0.045; Tmax, P = 0.016; and Cmax, P = 0.003).Based on ROTEM and TG assays, the anticoagulant effects induced by the 2 drugs given in the specific dose regimens in real-world patients were comparable. Only platelet aggregation was found to be more affected by dabigatran as compared to rivaroxaban.