DNA structural deformations in the interaction of the controller protein C.AhdI with its operator sequence

Controller proteins such as C.AhdI regulate the expression of bacterial restriction–modification genes, and ensure that methylation of the host DNA precedes restriction by delaying transcription of the endonuclease. The operator DNA sequence to which C.AhdI binds consists of two adjacent binding sites, OL and OR. Binding of C.AhdI to OL and to OL + OR has been investigated by circular permutation DNA-bending assays and by circular dichroism (CD) spectroscopy. CD indicates considerable distortion to the DNA when bound by C.AhdI. Binding to one or two sites to form dimeric and tetrameric complexes increases the CD signal at 278 nm by 40 and 80% respectively, showing identical local distortion at both sites. In contrast, DNA-bending assays gave similar bend angles for both dimeric and tetrameric complexes (47 and 38°, respectively). The relative orientation of C.AhdI dimers in the tetrameric complex and the structural role of the conserved Py-A-T sequences found at the centre of C-protein-binding sites are discussed

DNA structural deformations in the interaction of the controller protein C.AhdI with its operator sequence

Controller proteins such as C.AhdI regulate the expression of bacterial restriction–modification genes, and ensure that methylation of the host DNA precedes restriction by delaying transcription of the endonuclease. The operator DNA sequence to which C.AhdI binds consists of two adjacent binding sites, OL and OR. Binding of C.AhdI to OL and to OL + OR has been investigated by circular permutation DNA-bending assays and by circular dichroism (CD) spectroscopy. CD indicates considerable distortion to the DNA when bound by C.AhdI. Binding to one or two sites to form dimeric and tetrameric complexes increases the CD signal at 278 nm by 40 and 80% respectively, showing identical local distortion at both sites. In contrast, DNA-bending assays gave similar bend angles for both dimeric and tetrameric complexes (47 and 38°, respectively). The relative orientation of C.AhdI dimers in the tetrameric complex and the structural role of the conserved Py-A-T sequences found at the centre of C-protein-binding sites are discussed

A Pragmatic, Scalable Approach to Correct-by-Construction Process Composition Using Classical Linear Logic Inference

The need for rigorous process composition is encountered in many situations pertaining to the development and analysis of complex systems. We discuss the use of Classical Linear Logic (CLL) for correct-by-construction resource-based process composition, with guaranteed deadlock freedom, systematic resource accounting, and concurrent execution. We introduce algorithms to automate the necessary inference steps for binary compositions of processes in parallel, conditionally, and in sequence. We combine decision procedures and heuristics to achieve intuitive and practically useful compositions in an applied setting.Comment: Post-proceedings paper presented at the 28th International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR 2018), Frankfurt am Main, Germany, 4-6 September 2018 (arXiv:1808.03326). arXiv admin note: substantial text overlap with arXiv:1803.0261

The thrombotic potential of oral pathogens

In recent times the concept of infectious agents playing a role in cardiovascular disease has attracted much attention. Chronic oral disease such as periodontitis, provides a plausible route for entry of bacteria to the circulation. Upon entry to the circulation, the oral bacteria interact with platelets. It has been proposed that their ability to induce platelet aggregation and support platelet adhesion is a critical step in the pathogenesis of the infection process. Many published studies have demonstrated multiple mechanisms through which oral bacteria are able to bind to and activate platelets. This paper will review the various mechanisms oral bacteria use to interact with platelets

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

Architectures and algorithms of delivering multimedia content in IPTV environments

288 σ.Η διαδικτυακή τηλεόραση έχει αναπτυχθεί τεχνολογικά και βρίσκεται σε πλήρη επιχειρηματική ανάπτυξη την τελευταία δεκαετία. Παράλληλα τεχνολογίες διανομής πολυμεσικού περιεχομένου και κυρίως διαδικτυακού βίντεο παρέχονται στους χρήστες μέσω πολλαπλών αλγορίθμων, αρχιτεκτονικών σε πλατφόρμες διαδικτυακής τηλεόρασης. Όσο η τηλεόραση «μεταναστεύει» προς το διαδίκτυο, τόσο μεγαλύτερη είναι η ώθηση για την παροχή προηγμένων εξατομικευμένων υπηρεσιών στους χρήστες. Το ζητούμενο την σημερινή εποχή είναι η μετάδοση πολυμεσικού περιεχομένου σε οποιαδήποτε συσκευή, οποιαδήποτε στιγμή, οπουδήποτε. Αυτή η ανάγκη διαμορφώνει και το νέο οικοσύστημα της διαδικτυακής τηλεόρασης λαμβάνοντας υπόψη πλέον τις προτιμήσεις και την εξατομίκευση του χρήστη. Οδηγούμαστε στην τηλεόραση κοινωνικής δικτύωσης (Social TV) που ο χρήστης σαν μέλος μίας κοινωνικής ομάδας μπορεί να παρεμβαίνει και να διαμορφώνει την τηλεοπτική εμπειρία. Η παρούσα διατριβή εξετάζει τους αλγορίθμους και τις αρχιτεκτονικές πρόσβασης και παροχής υπηρεσιών πολυμέσων σε περιβάλλοντα διαδικτυακής τηλεόρασης. Παρουσιάζει όλο το μοντέλο από την IPTV 1.0 στην IPTV 3.0, που αποτελεί και το νέο μοντέλο μετάδοσης πολυμεσικού περιεχομένου. Η εξατομίκευση της διαδικτυακής τηλεόρασης και η διαμόρφωση ενός νέου μοντέλου ενημερωμένων τεχνολογικά και καταρτισμένων χρηστών χωρίς γεωγραφικά, κοινωνικά και οικονομικά όρια οδηγεί την νέα εμπειρία της τηλεόρασης. Εξετάζονται αλγόριθμοι μετάδοσης πολυμεσικού περιεχομένου σε αρχιτεκτονικές παροχής τριπλής υπηρεσίας αναλύοντας τα αποτελέσματα απόδοσης σε προσομοιωμένο περιβάλλον. Εξετάζει τα νέα πρότυπα στην λειτουργία και αξιοποίηση των συστημάτων δικτύων επικεντρωμένων στην πληροφορία για την διανομή πολυμεσικού περιεχομένου. Παράλληλα εξετάζεται το ζήτημα της ψηφιακής διαχείρισης των δικαιωμάτων που αποτελεί και προτείνεται με βάση το υφιστάμενο ρυθμιστικό κανονιστικό πλαίσιο, η θέσπιση ενός κατ΄αποκοπή τέλους για την κάλυψη των συλλογικών δικαιωμάτων.Internet Protocol Television (IPTV) has been deployed commercially for close to 10 years now. That time has seen an avalanche of other, Internet Protocol (IP) based video services delivered to users through multiple algorithms, architectures in IPTV environments. As more and more TV content migrates to the Internet, “personal” video choices are becoming the norm, not the exception, for IPTV as well as Internet Video. What is important nowadays, is the transformations in how media are managed and delivered promise a world of personalized content and services delivered to any device, anytime, anywhere. This concept shapes the new ecosystem of IPTV. These transformative capabilities taken together enable Social TV, where the user as a member of a social community can exchange viewing habits, preferences etc. Simply the user can “control” and influence the TV experience. This dissertation examines the algorithms and the architectures of delivering multimedia content in IPTV environments. It presents the whole concept from IPTV 1.0 to IPTV 3.0, which represents the new model of provisioning and delivering personalized multimedia content to user anywhere on any combination of devices. The personalization of IPTV and the moulding of a new model of well – informed users without any geographical, social and financial limits, leads the new TV experience. It examines algorithms for delivery of multimedia content on triple play networks and the testbed, the simulation network and the selected parameters for the collection of the results are presented. It examines the new models of delivery multimedia content based on Information Centric Networks. Also provides all the surrounding blocks in refer to Digital Rights Management, based on the existing European Regulatory Framework of Electronic Communication and recommends a flat rate fee in order to cover the issue of protection of the related rights.Σταύρος Ι. Παπαπαναγιώτο

Multiple resistance of silky windgrass to acetolactate synthase-and acetyl-CoA synthase-inhibiting herbicides

Field and pot experiments were conducted in Greece to study the occurrence of resistance in silky windgrass to acetolactate synthase (ALS)-and acetyl-CoA synthase (ACCase)-inhibiting herbicides. Twenty-four populations of silky windgrass were examined in whole-plant response experiments. High levels of field-evolved resistance to chlorsulfuron (0% to 28% control in terms of fresh weight reduction) with the recommended field rates were confirmed in most silky windgrass populations. However, other ALS inhibitors, such as pyroxsulam and a premix of mesosulfuron-methyl and iodosulfuron, provided adequate control (76% to 100% in terms of fresh weight reduction) of most populations, except eight silky windgrass populations that were found to be cross-resistant to all ALS-inhibiting herbicides tested (i.e., chlorsulfuron, commercial mixture of mesosulfuron-methyl plus iodosulfuron, and pyroxsulam). Conversely, most silky windgrass populations were controlled effectively (90% to 100% in terms of fresh weight reduction) with the recommended field rates of ACCase inhibitors cycloxydim, clethodim, and pinoxaden, but five populations were also found to be resistant to clodinafop-propargyl (10% to 68% control in terms of fresh weight reduction). The ALS gene sequencing of the eight silky windgrass populations, with cross-resistance to ALS inhibitors, revealed a point mutation at the Pro-197 position, causing amino acid substitution by Ser or Thr in the ALS enzyme. Overall, chlorsulfuron and clodinafop-propargyl were selecting agents of field-evolved multiple resistance to ALS-and ACCase-inhibiting herbicides in five silky windgrass populations. As the available postemergence-applied chemistries/modes of action registered for grass weed control in cereals are rather limited, adopting integrated management practices and implementing proactive and reactive measures to delay the evolution of resistant populations is essential.

The role of hemoglobin degradation pathway in preeclampsia: A systematic review and meta-analysis

Introduction: Overproduction of fetal hemoglobin by the placenta leading to increased consumption of endogenous heme scavenging proteins has been recently implicated as a novel pathway in the pathogenesis of preeclampsia. The aim of the present systematic review was to evaluate maternal serum levels of fetal hemoglobin, haptoglobin, heme oxygenase-1, hemopexin and α1-microglobulin, as well as haptoglobin phenotypes among preeclamptic and healthy pregnant women and assess their predictive role in the disease. Methods: Medline, Scopus, CENTRAL, Clinicaltrials.gov and Google Scholar databases were systematically searched from inception. All studies comparing levels of fetal hemoglobin or heme scavengers among preeclamptic and healthy pregnant controls were deemed eligible. Results: Twenty-three studies were included, with a total number of 7461 pregnant women. Quantitative synthesis was not conducted for the comparison of serum levels due to high heterogeneity. Current evidence suggests that preeclampsia is associated with increased levels of fetal hemoglobin and α1-microglobulin, as well as with lower levels of serum hemopexin. Data regarding serum haptoglobin and heme oxygenase-1 were conflicting, as the available evidence did not unanimously suggest a significant change of their levels in the disease. Network meta-analysis indicated no significant association for any of the haptoglobin phenotypes with preeclampsia development. Discussion: The present review suggests that preeclampsia may be associated with increased fetal hemoglobin and α1-microglobulin and decreased hemopexin levels, although inter-study heterogeneity was high. Future large-scale studies are needed to fully elucidate the predictive efficacy of these markers by introducing cut-off values and defining the optimal gestational age for sampling. © 2020 Elsevier Lt

Comparative efficacy and safety of oral antihypertensive agents in pregnant women with chronic hypertension: a network metaanalysis

Objective Data: Chronic hypertension is associated with adverse perinatal outcomes, although the optimal treatment is unclear. The aim of this network metaanalysis was to simultaneously compare the efficacy and safety of antihypertensive agents in pregnant women with chronic hypertension. Study: Medline, Scopus, CENTRAL, Web of Science, Clinicaltrials.gov, and Google Scholar databases were searched systematically from inception to December 15, 2019. Both randomized controlled trials and cohort studies were held eligible if they reported the effects of antihypertensive agents on perinatal outcomes among women with chronic hypertension. Study Appraisal and Synthesis Methods: The primary outcomes were preeclampsia and small-for-gestational-age risk. A frequentist network metaanalytic random-effects model was fitted. The main analysis was based on randomized controlled trials. The credibility of evidence was assessed by taking into account within-study bias, across-studies bias, indirectness, imprecision, heterogeneity, and incoherence. Results: Twenty-two studies (14 randomized controlled trials and 8 cohorts) were included, comprising 4464 women. Pooling of randomized controlled trials indicated that no agent significantly affected the incidence of preeclampsia. Atenolol was associated with significantly higher risk of small-for-gestational age compared with placebo (odds ratio, 26.00; 95% confidence interval, 2.61–259.29) and is ranked as the worst treatment (P-score=.98). The incidence of severe hypertension was significantly lower when nifedipine (odds ratio, 0.27; 95% confidence interval, 0.14–0.55), methyldopa (odds ratio, 0.31; 95% confidence interval, 0.17–0.56), ketanserin (odds ratio, 0.29; 95% confidence interval, 0.09–0.90), and pindolol (odds ratio, 0.17; 95% confidence interval, 0.05–0.55) were administered compared with no drug intake. The highest probability scores were calculated for furosemide (P-score=.86), amlodipine (P-score=.82), and placebo (P-score=.82). The use of nifedipine and methyldopa were associated with significantly lower placental abruption rates (odds ratio, 0.29 [95% confidence interval, 0.15–0.58] and 0.23 [95% confidence interval, 0.11–0.46], respectively). No significant differences were estimated for cesarean delivery, perinatal death, preterm birth, and gestational age at delivery. Conclusion: Atenolol was associated with a significantly increased risk for small-for-gestational-age infants. The incidence of severe hypertension was significantly lower when nifedipine and methyldopa were administered, although preeclampsia risk was similar among antihypertensive agents. Future large-scale trials should provide guidance about the choice of antihypertensive treatment and the goal blood pressure during pregnancy. © 2020 Elsevier Inc