Valorization of Spirodela polyrrhiza biomass for the production of biofuels for distributed energy.

Considering the main objectives of a circular economy, Lemnaceae plants have great potential for different types of techniques to valorize their biomass for use in biofuel production. For this reason, scientific interest in this group of plants has increased in recent years. The aim of this study was to evaluate the effects of salt stress on the growth and development of S. polyrrhiza and the valorization of biomass for biofuel and energy production in a circular economy. Plants were grown in a variety of culture media, including standard 'Z' medium, tap water, 1% digestate from a biogas plant in Piaszczyna (54° 01' 21″ N, 17° 10' 19″ E), Poland) and supplemented with different concentrations of NaCl (from 25 to 100 mM). Plants were cultured under phytotron conditions at 24 °C. After 10 days of culture, plant growth, fresh and dry biomass, as well as physio-chemical parameters such as chlorophyll content index, gas exchange parameters (net photosynthesis, transpiration, stomatal conductance and intercellular CO2 concentration), chlorophyll fluorescence measurements were analyzed. After 10 days of the experiment, the percentage starch content of Spirodela shoot segments was determined. S. polyrrhiza was shown to have a high starch storage capacity under certain unfavorable growth conditions, such as salt stress and nutrient deficiency. In the W2 (50 mM NaCl) series, compared to the control (Control2), starch levels were 76% higher in shoots and 30% lower in roots. The analysis of the individual growth and development parameters of S. polyrrhiza plants in the experiment carried out indicates new possibilities for the use of this group of plants in biofuel and bioethanol production.

Five-year morbidity and mortality of patients with ischemia with non-obstructive coronary artery disease and myocardial single-photon emission computed tomography perfusion defects.

INTRODUCTION: Patients with angina and a positive single-photon emission computed tomography (SPECT) scan for reversible ischemia, with no or non-obstructive coronary artery disease (CAD) on invasive coronary angiography (ICA), represent a frequent clinical problem and predicting prognosis is challenging. METHODS: This was a retrospective single-center study on patients who underwent elective ICA with angina and a positive SPECT with no or non-obstructive CAD over a seven-year period. Cardiovascular morbidity, mortality, and major adverse cardiac events were assessed during a follow-up of at least three years after ICA, with the aid of a telephone questionnaire. RESULTS: Data on all patients who underwent ICA in our hospital over a period of seven years (between January 1, 2011 and December 31, 2017) were analyzed. A total of 569 patients fulfilled the pre-specified criteria. In the telephone survey, 285 (50.1%) were successfully contacted and agreed to participate. Mean age was 67.6 (SD 8.8) years (35.4% female) and mean follow-up was 5.53 years (SD 1.85). Mortality was 1.7% (four patients, from non-cardiac causes), 1.7% underwent revascularization, 31 (10.9%) were hospitalized for cardiac reasons and 10.9% reported symptoms of heart failure (no patients with NYHA class>II). Twenty-one had arrhythmic events and only two had mild anginal symptoms. It was also noteworthy that mortality in the uncontacted group (12 out of 284, 4.2%), derived from public social security records, did not differ significantly from the contacted group. CONCLUSIONS: Patients with angina, a positive SPECT for reversible ischemia and no or non-obstructive CAD on ICA have excellent long-term cardiovascular prognosis for at least five years.

Effects of antifouling compounds on the growth of macroalgae Undaria pinnatifida.

Seaweeds are some of the principal primary producers of marine environments, and they are important ecological elements of coastal ecosystems. The effects of harmful chemicals on seaweeds may adversely affect coastal ecosystems, hence we aimed to develop a new phytotoxicity test using the gametophytes of a common temperate kelp species, Undaria pinnatifida (KU-1630), for the widely used antifouling chemical substances Cybutryne, Diuron, Cu2+, and Zn2+. Toxicity to gametophytes of U. pinnatifida was assessed by comparing the relative growth rate (RGR) at the logarithmic growth phase. Fragmentation method, initial algal biomass, photon irradiance, and adhesive period were investigated for developing optimal test conditions. Cybutryne exposure tests were performed with seven replicates and control, the RGR ranging from 0.17 to 0.19, while mean 7-day EC50 and no observed effect concentration (NOEC) were 5.1 µg/L and 1.8 µg/L, respectively. The 7-day EC50 for other antifoulants was 14 µg/L for Diuron, 17 µg/L for Cu2+, and 1500 µg/L for Zn2+. This test method demonstrated high sensitivity and reproducibility, and it may be added to the routine methods used for toxicity evaluation of hazardous chemicals.

Doctors' Perceptions, Attitudes and Practices towards the Management of Multidrug-Resistant Organism Infections after the Implementation of an Antimicrobial Stewardship Programme during the COVID-19 Pandemic.

BACKGROUND: Greece is among the European countries with the highest consumption of antibiotics, both in community and hospital settings, including last-line antibiotics, such as carbapenems. We sought to explore doctors' perceptions, attitudes and practices towards the management of patients with multidrug-resistant organism (MDRO) infections after the implementation of an antimicrobial stewardship programme (ASP) in a tertiary academic hospital during the COVID-19 pandemic. METHODS: A self-administered, internet-based questionnaire survey was completed by doctors of the University Hospital of Heraklion in Crete, Greece. RESULTS: In total, 202 (59.1%) hospital doctors fully completed the questionnaire. Most of them agreed that the prospective audit and feedback ASP strategy is more effective and educational than the preauthorization ASP strategy. ASP implementation prompted most respondents to monitor the continuously evolving microbiological data of their patients more closely and affected them towards a multidisciplinary and personalised care of patients with infections caused by MDROs and towards a more rigorous implementation of infection prevention and control measures. The vast majority of participants (98.5%) stated that ASP must be continued and further developed during the COVID-19 pandemic. CONCLUSION: The ASP implementation in our hospital had a beneficial impact on doctors' perceptions, attitudes and practices with regard to the management of infections due to MDROs.

How to keep up to date with medical information using web-based resources: a systematised review and narrative synthesis.

BACKGROUND: Keeping up to date with the latest medical information using Web-based resources has been sparsely described, and a comprehensive up-to-date review is needed. OBJECTIVES: To summarise the Web-based 'channels' that may assist the actors of the health care system (clinicians, medical researchers and students) to keep up to date with medical information. METHODS: We searched PubMed and Scopus for English language articles published between January 1990 and February 2019 that investigated ways for keeping up with medical information. We used the results from our search and relevant information from other sources to conduct a narrative synthesis. RESULTS: We found that resources that push information (e.g. web alerts, medical newsletters, listservs), resources that rely on the active information seeking (e.g. access to health librarians and electronic databases, podcasts, mobile apps), collaborative resources (e.g. web conferences, online journal clubs, web social media) and resources that synthesise information (e.g. bibliometrics, living systematic reviews) can contribute in keeping up with new findings and can enhance evidence-based medicine. Clinicians, medical researchers and students can benefit from the proper use of such Internet-based technological innovations. CONCLUSION: Internet provides many resources that can help the actors of the health care system stay up to date with the latest scientific findings.

Argo: a data analysis program for quantum chemical calculations.

The ARGO program is designed for the analysis and display of results obtained from quantum chemical calculations. ARGO currently extracts values of geometrical parameters and energy of each conformer obtained from potential energy surface (PES) scans. It automatically arranges the data into columns and prepares input files for the Gnuplot graphing utility for two- and three-dimensional PES graphs. In addition, it transforms Raman activities into Raman intensities and calculates the IR or Raman intensity ratios. This software, which was written in Python, is freely available, open-source, easy to modify, and pleasant to use. Extensive documentation is also provided with examples and suggestions for code modifications. We plan to create a collaborative program package aimed at delivering endless variety and possibilities for fast and accurate data analysis of quantum chemical calculations.

Evaluation of four mesh fixation methods in an experimental model of ventral hernia repair.

BACKGROUND: The present animal study was conducted to comparably investigate the performance of four different fixation techniques of intraperitoneally implanted meshes. MATERIALS AND METHODS: Fifteen New Zealand white rabbits were used. In each animal, four abdominal wall defects were created and repaired with four pieces of intraperitoneal mesh (Parietex Composite), fixed with nonabsorbable (titanium) spiral tacks (group A), absorbable (lactic and glycolic acid co-polymer) screw-type tacks (group B), transfascial polypropylene sutures (group C), or fibrin glue (group D). Adhesion formation, mesh shrinkage, tensile strength, and host tissue response were evaluated at 90 d. RESULTS: Adhesions were observed in all groups, and differences were not significant. The percentage of shrinkage was higher in group C (26.91%), lower in group D (12%), whereas in groups A and B, the mean shrinkage was 20.17% and 23.33%, respectively (P = 0.032). The incorporation of mesh fixation element to the abdominal wall was 9.18 ± 3.91 N, 6.96 ± 3.0 N, 13.68 ± 5.38 N, and 2.57 ± 1.29 N, in groups A, B, C, and D, respectively (P < 0.001). Regarding local inflammatory response and foreign body reaction, no difference was observed between groups. However, with respect to fibrous tissue presence, its quantity was clearly less in group D compared with the other groups (P < 0.001). CONCLUSIONS: None of the examined fixation techniques proved to be ideal. Probably, the best way to fixate an intraperitoneally implanted mesh may be achieved using a combination of the studied materials. Prospective randomized trials are needed to confirm the superiority of the combined use of different fixation devices in clinical practice.

Multiple coronary micro-aneurysm formation after drug-eluting stent implantation.

Although there are limited data regarding the formation of coronary artery aneurysms (CAAs) after drug-eluting stent (DES) implantation, CAAs appear to be a rare complication of coronary stenting. The exact mechanism of CAA formation is unknown, but several hypotheses have been proposed. As the use of DES increases, the clinical significance of these findings will become clearer. We report on a patient who developed multiple CAAs in 2 different locations after sirolimus-eluting stent implantation.

Assessment of wastewater effluent quality in Thessaly region, Greece, for determining its irrigation reuse potential.

The objective of the present study is to assess wastewater effluent quality in Thessaly region, Greece, in relation to its physicochemical and microbiological burden as well as its toxic potential on a number of organisms. Wastewater may be used for agricultural as well as for landscape irrigation purposes; therefore, its toxicity potential is quite important. Thessaly region has been chosen since this region suffers from a distinct water shortage in summer period necessitating alternative water resources. During our research, treated effluents from four wastewater treatment plants operating in the region (Larissa, Volos, Karditsa, and Tirnavos) were tested for specific physicochemical and microbiological parameters [biochemical oxygen demand (BOD(5)), chemical oxygen demand (COD), total suspended solids (TSS), pH, electrical conductivity, selected metals presence (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn, As), and fecal coliforms' (FC) number]. The effluents were also tested for their toxicity using two different bioassays (Daphnia magna immobilization test and Phytotoxkit microbiotest). The findings were compared to relative regulations and guidelines regarding wastewater reuse for irrigation. The results overall show that secondary effluents in Thessaly region are generally acceptable for reuse for irrigation purposes according to limits set by legislation, if effective advanced treatment methods are applied prior to reuse. However, their potential toxicity should be closely monitored, since it was found that it may vary significantly in relation to season and location, when indicator plant and zooplankton organisms are used.

Evaluation of toxic and interactive toxic effects of three agrochemicals and copper using a battery of microbiotests.

Three commonly used test organisms of different trophic levels (Vibrio fischeri, Pseudokirchneriella subcapitata and Daphnia magna) were exposed to selected agrochemicals (fosthiazate, metalaxyl-M, imidacloprid) and copper, in single doses or in binary mixtures. The toxicity of each single compound varied up to two orders of magnitude, depending on the test species examined. V. fischeri was the most sensitive test organism regarding fosthiazate and metalaxyl-M, indicating an IC(50) value of 0.20 mg/L (0.17-0.25 mg/L) and 0.88 mg/L (0.35-1.57 mg/L), respectively. Imidacloprid was the least toxic compound, indicating an EC(50) value on D. magna of 64.6 mg/L (43.3-122.5 mg/L) and an IC(50) value on V. fischeri of 226 mg/L (159-322 mg/L), while for imidacloprid at a concentration of 1000 mg/L the effect on P. subcapitata was lower than 50%. Copper was the most toxic compound towards all test organisms exhibiting the highest toxic effect on P. subcapitata, with an IC(50) value of 0.05 mg/L (0.003-0.008 mg/L). The toxic effects of the binary mixtures have been compared to the theoretically expected effect, resulting from a simple mathematical model based on the theory of probabilities. The independent action model was used in order to predict the theoretically expected effect. The interactive effects were mostly antagonistic or additive, while in few cases (interactive effects of metalaxyl-M and copper on V. fischeri) a synergistic mode of action was observed for some concentration combinations. Experiments showed that interactive effects of chemicals may vary depending on the test species used as well as on the chemicals and their respective concentrations. Although most of the concentrations of chemicals tested in this study are higher than the ones usually found in natural environment, the evaluation of their interactive toxic effects using a battery of bioassays may comprise a useful tool for the estimation of the environmental hazard of chemicals.

Macromolecule oxidation and DNA repair in mussel (Mytilus edulis L.) gill following exposure to Cd and Cr(VI).

The oxidation of DNA and lipid was analysed in the marine mussel (Mytilus edulis) in response to exposure (10microg/l and 200microg/l) to cadmium (Cd) and chromium [Cr(VI)]. Concentration dependent uptake of both metals into mussel tissues was established and levels of gill ATP were not depleted at these exposure levels. DNA strand breakage in gill cells (analysed by the comet assay) was elevated by both metals, however, DNA oxidation [measured by DNA strand breakage induced by the DNA repair enzyme formamidopyrimidine glycosylase (FPG)] was not elevated. This was despite a statistically significant increase in both malondialdehyde and 4-hydroxynonenal - indicative of lipid peroxidation - following treatment with Cd. In contrast, both frank DNA stand breaks and FPG-induced DNA strand breaks (indicative of DNA oxidation) were increased following injection of mussels with sodium dichromate (10.4microgCr(VI)/mussel). The metals also showed differential inhibitory potential towards DNA repair enzyme activity with Cd exhibiting inhibition of DNA cutting activity towards an oligonucleotide containing 8-oxo-7,8-dihydro-2'-deoxyguanosine and Cr(VI) showing inhibition of such activity towards an oligonucleotide containing ethenoadenosine, both at 200microg/l. The metals thus show DNA damage activity in mussel gill with distinct mechanisms involving both direct and indirect (oxidative) DNA damage, as well as impairing different DNA repair capacities. A combination of these activities can contribute to adverse effects in these organisms.