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Acid-fast bacteria can be implicated in skin and soft tissue infections. Diagnostic identification can be challenging or not feasible by routine laboratory techniques, especially if there is no access to the Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) technology. Here, we present two cases of skin and soft tissue infections caused by two different acid-fast bacteria, Nocardia brasiliensis and Mycobacterium marinum. They both grew on Löwenstein–Jensen medium, Sabouraud agar medium and blood agar medium. Both bacteria appeared acid-fast by Ziehl–Neelsen stain and Gram-positive by Gram stain. The identification was performed by MALDI-TOF MS and gene analysis. N. brasiliensis and nontuberculous mycobacterium M. marinum represent rare pathogens that cause severe skin and soft tissue infections. Failure to identify the causative agent and subsequent inappropriate or inadequate treatment may lead to severe complications or even disseminated disease, especially in immunocompromised individuals.

Οι περισσότερες μεγαλουπόλεις των ανεπτυγμένων χωρών διαθέτουν ένα εκτεταμένο δίκτυο αστικών και περι-αστικών αυτοκινητοδρόμων, το οποίο στοχεύει στην ουσιαστικά ανεμπόδιστη και γρήγορη κίνηση των οχημάτων γύρω από τα αστικά κέντρα. Εντούτοις, η αύξηση της κυκλοφοριακής ζήτησης, ιδιαίτερα κατά τις ώρες αιχμής, σε συνδυασμό με την εμφάνιση διαφόρων περιστατικών, οδηγεί στην καθημερινή δημιουργία κυκλοφοριακής συμφόρησης η οποία έχει ως αποτέλεσμα τη σημαντική αύξηση των χρόνων διαδρομής των οχημάτων, την αύξηση της κατανάλωσης καυσίμων, την περιβαλλοντική ρύπανση και τη μειωμένη οδική ασφάλεια.Το πρόβλημα της συμφόρησης στους αστικούς και περι-αστικούς αυτοκινητοδρόμους δεν μπορεί πάντοτε να αντιμετωπιστεί με την επέκταση των ήδη υπάρχοντων υποδομών, για οικονομικούς αλλά και περιβαλλοντικούς λόγους. Αντιθέτως, κατάλληλα μέτρα ελέγχου κυκλοφορίας μπορούν να εφαρμοστούν για να αντιμετωπίσουν το πρόβλημα. Η ανάπτυξη αποτελεσματικών μέτρων ελέγχου κυκλοφορίας προϋποθέτει την ύπαρξη κατάλληλων μαθηματικών μοντέλων κυκλοφοριακής ροής τα οποία μπορούν να χρησιμοποιηθούν για την ανάπτυξη και δοκιμή των προτεινόμενων στρατηγικών ελέγχου. Η εργασία αυτή διερευνά την ιδιαίτερη, αλλά συχνά εμφανιζόμενη, περίπτωση της κυκλοφοριακής συμφόρησης σε αυτοκινητοδρόμους η οποία οφείλεται σε κορεσμένες ράμπες εξόδου. Αυτό το είδος συμφόρησης είναι δύσκολο να αντιμετωπιστεί και για το λόγο αυτό δεν υπάρχουν πολλές αναφορές στη διεθνή βιβλιογραφία σχετικά με κατάλληλα μέτρα ελέγχου κυκλοφορίας για αυτές τις περιοχές. Επιπλέον, στην αντίστοιχη βιβλιογραφία που αφορά τη μοντελοποίηση της κυκλοφοριακής ροής σε οδικά δίκτυα, δεν υπάρχουν μελέτες που να πραγματοποιούν σύγκριση και αξιολόγηση διαφορετικών μοντέλων κυκλοφοριακής ροής σχετικά με την ικανότητά τους να αναπαριστούν τις κυκλοφοριακές συνθήκες σε αυτές τις περιοχές. Ο στόχος της παρούσας έρευνας είναι να διερευνήσει θέματα μοντελοποίησης και ελέγχου της κυκλοφοριακής ροής σε περιοχές ραμπών εξόδου αυτοκινητοδρόμων υπό συμφόρηση.Ιδιαίτερα, στην παρούσα διατριβή τα δύο πιο δημοφιλή, μακροσκοπικά μοντέλα κυκλοφοριακής ροής, συγκεκριμένα το CTM και το ΜΕΤΑΝΕΤ, αξιολογούνται και συγκρίνονται σχετικά με την ικανότητά τους να αναπαριστούν τις κυκλοφοριακές συνθήκες σε περιοχές ραμπών εξόδου αυτοκινητοδρόμων υπό συμφόρηση. Τα μοντέλα βαθμονομούνται και αξιολογούνται κάνοντας χρήση πραγματικών δεδομένων κυκλοφορίας από ένα τμήμα του αυτοκινητοδρόμου της Αττικής Οδού, στην Αθήνα. Εκτός από τα θέματα μοντελοποίησης, διαφορετικά μέτρα ελέγχου κυκλοφορίας προτείνονται για την περίπτωση περιοχών ραμπών εξόδου αυτοκινητοδρόμων υπό συμφόρηση. Συγκεκριμένα, δύο διαφορετικές περιπτώσεις εξετάζονται και κατάλληλες στρατηγικές ελέγχου κυκλοφορίας προτείνονται για κάθε περίπτωση. Στην πρώτη περίπτωση που εξετάζεται, ένα υποθετικό δίκτυο χρησιμοποιείται και διαφορετικές στρατηγικές καθοδήγησης πορείας αναπτύσσονται, οι οποίες στοχεύουν να καθοδηγήσουν τους οδηγούς μέσω εναλλακτικών διαδρομών. Σκοπός των στρατηγικών ελέγχου είναι να προστατεύσουν την κορεσμένη ράμπα εξόδου και να αποτρέψουν την υπερχείλιση της ουράς οχημάτων της ράμπας στον αυτοκινητόδρομο και τη δημιουργία συμφόρησης στο κυρίως ρεύμα του αυτοκινητοδρόμου. Στη δεύτερη περίπτωση, ένα πραγματικό δίκτυο εξετάζεται όπου η συμφόρηση στον αυτοκινητόδρομο οφείλεται στην συμφόρηση που έχει δημιουργηθεί στο παράπλευρο αστικό δίκτυο, η οποία εισέρχεται στον αυτοκινητόδρομο μέσω μίας κορεσμένης ράμπας εξόδου. Το δίκτυο προσομοιώνεται μέσω του μικροσκοπικού προσομοιωτή οδικών δικτύων AIMSUN και μία στρατηγική ελέγχου πραγματικού χρόνου προτείνεται η οποία έχει στόχο να μεγιστοποιήσει τη ροή οχημάτων στο παράπλευρο δίκτυο και παράλληλα να εμποδίσει την είσοδο της ουράς οχημάτων της ράμπας εξόδου στο κυρίως ρεύμα του αυτοκινητοδρόμου. Τα αποτελέσματα των διερευνήσεων, και για τις δύο περιπτώσεις που εξετάστηκαν, έδειξε ότι τα προτεινόμενα μέτρα ελέγχου κυκλοφορίας μπορούν να βελτιώσουν τις κυκλοφοριακές συνθήκες που επικρατούν στο δίκτυο, εμποδίζοντας τη δημιουργία της συμφόρησης στο κυρίως ρεύμα του αυτοκινητοδρόμου. Το γεγονός αυτό καθιστά τις προτεινόμενες στρατηγικές ελέγχου πολλά υποσχόμενες σε περίπτωση ενδεχόμενης εφαρμογής τους στο πεδίο.

Introduction. Resistance rates to azoles and echinocandins of Candida spp. increased over the last decade. Hypothesis/Gap Statement. Widespread use of antifungals could lead to development and dissemination of resistant Candida spp. Aim. To identify risk factors for isolation of Candida spp. non-susceptible to either fluconazole or echinocandins. Methodology. All patients hospitalized in the Intensive Care Unit (ICU) of the University General Hospital of Patras, Greece with Candida spp. isolated from clinical specimens during a ten-year period (2010–19) were included. Candida isolates were identified using Vitek-2 YST card. Consumption of antifungals was calculated. Results. During the study period, 253 isolates were included. C. non-albicans predominated (64.4 %) with C. parapsilosis being the most commonly isolated (42.3 %) followed by C. glabrata (nomenclatural change to Nakaseomyces glabrataa; 8.7 %) and C. tropicalis (11.9 %). Among all isolates, 45.8 and 28.5 % were non-susceptible and resistant to fluconazole, respectively. Concerning echinocandins, 8.7 % of isolates were non-susceptible to at least one echinocandin (anidulafungin or micafungin) and 3.1 % resistant. Multivariate analysis revealed that hospitalization during 2015–19, as compared to 2010–14, isolate being non-albicans or non-susceptible to at least one echinocandin was associated with isolation of fluconazole non-susceptible isolate. Administration of echinocandin, isolate being C. glabrata or C. tropicalis, or Candida spp. non-susceptible to fluconazole were independently associated with isolation of Candida spp. non-susceptible to at least one echinocandin. Fluconazole’s administration decreased during the study period, whereas liposomal-amphotericin B’s and echinoncandins’ administration remained stable. Conclusion. Fluconazole’s non-susceptibility increased during the study period, despite the decrease of its administration. Although echinocandins’ administration remained stable, non-susceptibility among Candida spp. increased.

Paraoxonase-1 (PON-1), a calcium ion-dependent high-density lipoprotein (HDL)-associated enzyme, has been proposed as a negative acute phase reactant biomarker in animal and human adult studies. The aim of this study was to evaluate the value of PON-1 activity in the diagnosis and monitoring of neonatal sepsis. Serum PON-1 activity, as paraoxonase and arylesterase, was prospectively studied in 48 septic neonates and matched controls. PON-1 activity was decreased at the acute phase of sepsis in comparison with values at recovery and values in controls. Paraoxonase or arylesterase at enrollment correlated significantly with serum Amyloid-A, CRP and IL-6 and could also discriminate septic than non-septic neonates. In conclusion, our results are promising regarding the role of PON-1 as a biomarker of neonatal sepsis. Larger studies are needed to validate the clinical utility of PON-1 in neonatal medicine.

The aim of the present study was to analyze candidaemia’s epidemiology (incidence, species distribution, and susceptibility rates) and antifungal consumption during a 9-year period. All candidaemias recorded at The University General Hospital of Patras, Greece, between 2009 and 2017 were included. Candida isolates were identified using the germ tube test, API 20C AUX System, and/or Vitek-2 YST card. Antifungal susceptibility was determined by the gradient method according to CLSI. During the study period, 505 episodes of candidaemia were observed with an overall incidence of 1.5 episodes per 1000 hospital admissions (1.1 episodes in 2009 to 1.9 in 2017: P 0.038, r 0.694). C. albicans was the leading cause (200 cases; 39.6%), followed by C. parapsilosis (185; 36.6%), C. glabrata (56; 11.1%), C. tropicalis (50; 9.9%), C. krusei (8; 0.2%), C. lusitaniae (5

Summarization: This paper develops, investigates and demonstrates real-time route diversion policies in cases where recurrent freeway traffic congestion is created due to a saturated off-ramp. In particular, the proposed route diversion policies attempt to avoid the off-ramp queue spill-over onto the freeway mainstream and the resulting freeway congestion by appropriately re-routing the freeway vehicles through nearby off-ramps towards the same destination. The proposed route diversion concepts are based on feedback control laws and are tested for a hypothetical, but quite typical, network infrastructure and three different traffic scenarios by use of macroscopic simulation. In the first traffic scenario, the user-optimal conditions may be achieved without off-ramp queue spill-over and creation of mainstream congestion; thus the route guidance system may propose an alternative route without any disbenefit for the compliant drivers. In the second case, the user-optimal conditions may be achieved only after the off-ramp queue spills back to the mainstream freeway; thus the route diversion system will have to assume sufficient compliance to the proposed route choice; or be based on mandatory actions, such as temporary off-ramp closures. Finally, in the third examined case, the user-optimal conditions cannot be achieved, due to the traffic conditions on the alternative route, thus the route diversion system should decide for the temporary off-ramp closure, when and to the extent needed, in order to prevent formation of mainstream congestion. The obtained simulation results are compared to the case where no route guidance is applied to the network and reveal interesting features and the potential for significant improvements. Παρουσιάστηκε στο: Transportation Research Part A: Policy and Practice

Candida kefyr (Kluyveromyces marxianus), an ascomycetous environmental yeast, occasionally isolated from dairy products, represents an uncommon but emerging pathogen in immunocompromised patients. Herein, we present a case of C. kefyr pyelonephritis in a 41-year-old, previously immunocompetent, patient who was hospitalized in an COVID-19 ICU. Pyelonephritis was associated with caliectasis and obstruction due to possible fungus ball formation. Predisposing factors included ICU stay, use of broad spectrum antibiotics and steroids, central venous catheterization, mechanical ventilation and urologic manipulation. Susceptibility testing revealed high MIC values to amphotericin B. Infection was effectively controlled by prolonged administration of fluconazole without further surgical intervention. COVID-19 complicated with invasive candidiasis is an increasingly observed clinical situation that warrants high suspicion index and careful evaluation of laboratory data.

Purpose. Acinetobacter baumannii and Pseudomonas aeruginosa provoke serious infections, especially in intensive care unit (ICU) patients. Methodology. The risk factors and predictors of mortality for P. aeruginosa (n=84; 46 carbapenem-resistant) and A. baumannii (n=129; all carbapenem-resistant) bloodstream infections (BSIs) in an ICU were evaluated. Antibiotic susceptibility testing was performed using the agar disk diffusion method according to EUCAST guidelines. The minimum inhibitory concentration was determined by a gradient method (Etest). Multilocus sequence typing (MLST) was performed for P. aeruginosa during the carbapenem-resistant outbreak in 2014. Epidemiological data were collected from the patients’ chart reviews. Results/Key findings. Hospitalization during the summer months, prior KPC-producing Klebsiella pneumoniae (KPC-Kp) BSI, and the administration of tigecycline, aminoglycosides and cortisone were independently associated with P. aeruginosa BSIs. MLST revealed the dissemination of clone ST227, including carbapenem-resistant P. aeruginosa strains. Hospitalization during the summer months, prior KPC-Kp BSI, and the administration of antibiotics, carbapenem and cortisone were independently associated with A. baumannii BSIs. The 30-day mortality rate for P. aeruginosa and A. baumannii BSI was 45.2 and 39.5 %, respectively. Sequential organ failure assessment (SOFA) score at onset, septic shock, age, and prior KPC-Kp BSI were significantly associated with P. aeruginosa BSI mortality. The administration of at least one active antibiotic was identified as a predictor of a good prognosis. Septic shock and simplified acute physiology score (SAPS) II at onset were independently associated with A. baumannii BSI mortality. The administration of at least one active antibiotic and colistin–vancomycin co-administration were identified as predictors of a good prognosis. Conclusion. KPC-Kp infection predisposes ICU patients to BSI by either A. baumannii or P. aeruginosa. The administration of at least one active antibiotic leads to better survival rates.

The aim of the present study is to identify risk factors for development and predictors of mortality of candidaemia among critically ill patients. A 1:7 case–control study was conducted during a 4-year period (2012–2015) in a Greek Intensive Care Unit (ICU). Candidaemia was confirmed by positive blood cultures. All yeasts were identified using API 20C AUX System or Vitek 2 Advanced Expert System. Epidemiologic data were collected from the ICU computerized database and patients’ chart reviews. Fifty-three patients developed candidaemia with non-albicans species being the predominant ones (33 patients, 62.3%). Multivariate analysis found that prior emergency surgery, malignancy, hospitalization during summer months, prior septic shock by KPC-producing Klebsiella pneumoniae and number of antibiotics administered were independently associated with candidaemia, while, prior administration of azole was a protective factor. Non-albicans candidaemia was associated with number of antibiotics administered and prior administration of echinocandin. Mortality of 14 days was 28.3% (15 patients) and was associated with SOFA score upon infection onset and septic shock, while, appropriate empirical antifungal treatment was associated with better survival. Prophylactic azole administration prevents development of candidaemia, while, echinocandin administration predisposes to non-albicans candidaemia. Empirical administration of an appropriate antifungal agent is associated with better survival.

Acinetobacter baumannii is a typically short, almost round, rod-shaped (coccobacillus) Gram-negative bacterium. It can be an opportunistic pathogen in humans, affecting people with compromised immune systems, and it is becoming increasingly important as a hospital-associated (nosocomial) infection. It has also been isolated from environmental soil and water samples. In this work, unlike conventional medical methods like antibiotics, the influence of atmospheric-pressure cold plasma on this bacterium is evaluated by means of a colony count technique and scanning electron microscopy. The plasma used here refers to streamers axially propagating into a helium channel penetrating the atmospheric air. The plasma is probed with high resolution optical emission spectroscopy and copious reactive species are unveiled under low-temperature conditions. Based on the experimental results, post-treatment (delayed) biochemical effects on Acinetobacter baumannii and morphological modifications appear dominant, leading to complete deactivation of this bacterium.

This study presents a real-time merging traffic control algorithm to mitigate the problem of freeway congestion resulting from an overspilling off-ramp. The proposed control algorithm aims at maximizing the merge area outflow of the surface street and at the same time preventing the off-ramp queue spillover into the freeway mainstream and the resulting freeway congestion. The potential benefits obtained by applying the proposed control concept are demonstrated by the use of microscopic simulation applied to a real freeway network where recurrent freeway traffic congestion is created as a result of an overspilling off-ramp. The simulation results demonstrated that the proposed control algorithm may improve the prevailing traffic conditions, preventing the formation of freeway congestion and benefiting freeway drivers and surface street users.

Summarization: This study tests and compares different optimization algorithms employed for the calibration of a macroscopic traffic flow model. In particular, the deterministic Nelder–Mead algorithm, a stochastic genetic algorithm and the stochastic cross-entropy method are utilized to estimate the parameter values of the METANET model for a particular freeway site, using real traffic data. The resulting models are validated using various traffic data sets and the optimization algorithms are evaluated and compared with respect to the accuracy of the produced validated models as well as the convergence speed and the required computation time. The validation results showed that all utilized optimization algorithms were able to converge to robust model parameter sets, albeit achieving different performances considering the convergence speed and the required computation time. Παρουσιάστηκε στο: Operational Research

This study presents an ACC (Adaptive Cruise Control)-based traffic control strategy which aims to adapt in real time the driving behavior of ACC-equipped vehicles to the prevailing traffic conditions so that the motorway traffic flow efficiency is improved. The potential benefits obtained by applying the proposed control concept are demonstrated for different ACC penetration rates by use of validated microscopic simulation applied to a real motorway stretch where recurrent traffic congestion is created due to an on-ramp bottleneck. The simulation results demonstrate that, even for low penetration rates of ACC vehicles, the proposed control concept improves the average vehicle delay and fuel consumption by reducing the space-time extent of congestion compared to the case of only manually driven or regular ACC vehicles.

Clinical specimens from 565 patients hospitalized in 2 intensive care units (ICUs A and B) during a 28-month period were cultured on appropriate media for isolation of Candida. Forty-nine (9%) patients had at least a Candida spp.-positive sample. Candida albicans was the predominant species isolated from 26 (53%) patients. Seventeen patients (3%) developed candidemia. Multivariate analysis showed that obesity, female gender, hospitalization during summer months, admission at ICU B, parenteral nutrition, administration of metronidazole, transplantation, and KPC-producing Klebsiella pneumoniae (KPC-Kp) infection were independently associated with Candida spp. isolation. Candidemia was associated with cortisone administration, KPC-Kp infection, and presence of colostomy or abdominal catheter. Administration of fluconazole was a protective factor for both Candida spp. isolation and infection, leading to selection of Candida non-albicans species. Among several risk factors, KPC-Kp infection and colonization are identified as statistically significant factors associated with Candida isolation, especially of non-albicans species.

Work zones on motorways necessitate the drop of one or more lanes which may lead to significant reduction of traffic flow capacity and efficiency, traffic flow disruptions, congestion creation, and increased accident risk. Real-time traffic control by use of green–red traffic signals at the motorway mainstream is proposed in order to achieve safer merging of vehicles entering the work zone and, at the same time, maximize throughput and reduce travel delays. A significant issue that had been neglected in previous research is the investigation of the impact of distance between the merge area and the traffic lights so as to achieve, in combination with the employed real-time traffic control strategy, the most efficient merging of vehicles. The control strategy applied for real-time signal operation is based on an ALINEA-like proportional–integral (PI-type) feedback regulator. In order to achieve maximum performance of the control strategy, some calibration of the regulator’s parameters may be necessary. The calibration is first conducted manually, via a typical trial-and-error procedure. In an additional investigation, the recently proposed learning/adaptive fine-tuning (AFT) algorithm is employed in order to automatically fine-tune the regulator parameters. Experiments conducted with a microscopic simulator for a hypothetical work zone infrastructure, demonstrate the potential high benefits of the control scheme.

Summarization: The calibration of a macroscopic traffic flow model aims at enabling the model to reproduce, as accurately as possible, the real traffic conditions on a motorway network. Essentially, this procedure targets the best value for the parameter vector of the model and this can be achieved using appropriate optimization algorithms. The parameter calibration problem is formulated as a nonlinear, non-convex, least-squares optimization problem, which is known to attain multiple local minima; for this reason gradient-based solution algorithms are not considered to be an option. The methodologies that are more appropriate for application to this problem are mainly some meta-heuristic algorithms which use direct search approaches that allow them to avoid bad local minima. This paper presents an overview of the most suitable nonlinear programming methods for the calibration procedure of macroscopic traffic flow models. Furthermore, an application example, where two well-known macroscopic traffic flow models are evaluated through the calibration procedure, is presented. Παρουσιάστηκε στο: 2 nd International Symposium and 24 th National Conference on Operational Research

The reported study tests, validates and compares two well-known macroscopic traffic flow models in the special, but quite frequently occurring case, where congestion is created due to saturated freeway off-ramps. In particular, the comparison includes the first-order model CTM (Cell Transmission Model) and the second-order model METANET. In order to enable a reliable and fair comparison, the traffic flow models are first calibrated by use of real traffic data from Attiki Odos freeway in Athens, Greece. The resulting models are validated using various traffic data sets, different than the one used for their calibration; the models are then evaluated and compared with respect to their accuracy in the reproduction of congestion created at freeway off-ramp areas.

Rhodotorula species are commensal yeasts that have emerged as a cause of life-threatening fungemia in severely immunocompromised patients. A case of Rhodotorula mucilaginosa fungemia in a 48-year-old woman that had undergone consecutive abdominal surgeries due to ovarian cancer and bowel necrosis while she was receiving fluconazole prophylaxis is presented. Several risk factors were identified such as presence of central venous catheters, solid organ neoplasm, abdominal surgery and administration of antibiotics. Identification was performed using commercial systems. The yeast was resistant to fluconazole, posaconazole and voriconazole and to echinocandins, whereas MIC to amphotericin B was 1.5 mg/L. Furthermore, published cases of Rhodotorula spp fungemia during the last decade are reviewed. In conclusion, Rhodotorula spp must be considered a potential pathogen in patients with immunosupression and central venous catheters. Correct identification is mandatory for appropriate management, as Rhodotorula spp are resistant to antifungal agents, such as fluconazole and echinocandins.

Staphylococcus epidermidis is a leading cause of hospital-acquired and biofilm-associated infections. Interactions of peripheral blood mononuclear cells (PBMCs) and monocyte-derived macrophages with planktonic or biofilm phase S. epidermidis cells were studied. Biofilm phase bacteria exhibited higher attachment, as well as, a 10-fold higher intracellular survival in monocyte-derived macrophages than their planktonic counterparts. Stimulation of PBMCs and monocyte-derived macrophages was performed with live or formalin-fixed bacterial cells. Supernatant concentration of selected cytokines was measured by Luminex(®) xMAP(™) technology at different time points. As compared to planktonic phase, biofilm phase bacteria elicited lower amounts of proinflammatory cytokines and Th1 response cytokines, such as TNFα, IL-12p40, IL-12p70 and IFN-γ, whereas they enhanced production of IL-8, GM-CSF and IL-13. This phenomenon was independent of formalin pretreatment. Taken together, these results may contribute to interpretation of observed silent course of biofilm-associated infections.

Bacterial adherence to eukaryotic cells is highly contributing to microbial pathogenesis. Bacterial adhesins, macromolecules, and glycosaminoglycan chains of the endothelial cell surface have been implicated in staphylococcal attachment. Our research group has isolated an antigenic polysaccharidic component of Staphylococcus epidermidis extracellular layer, known as 20-kDa PS (PS), and showed that antibodies against this polysaccharide protect from infections. Therefore, the role of PS in S. epidermidis adherence to endothelial cells was studied. For this purpose we examined the impact of PS on the ability of two S. epidermidis strains (a PS-producing and a non-PS-producing strain) to adhere to human endothelial cells in the presence or absence of specific antibodies to this polysaccharide. Hence, it is established that exogenous chondroitin sulfate (CS) decreases, in part, the S. epidermidis' attachment to endothelial cells and the antagonistic binding effect of CS and PS was also studied. The results obtained demonstrate that PS facilitates the adherence of S. epidermidis to both strains. CS abolished the PS-induced adherence in PS-producing strain and partially in the non-PS-producing one. Conclusively, the adherence of S. epidermidis to human endothelial cells is associated with its extracellular PS component and it is suggested that the bacterial binding via glycosaminoglycan chains is an important mechanism underlining the PS-induced binding to endothelial cells.

Central venous catheters (CVCs) are commonly used for the administration of intravenous chemotherapy in outpatient setting. Nevertheless, outbreaks of catheter-associated bloodstream infections had been reported from oncology centers. We describe a large outbreak of CVCs-associated Klebsiella oxytoca bloodstream infection, occurring in an oncology chemotherapy outpatient unit of northern Greece between October 2006 and May 2007. The outbreak involved approximately 10% of the patients with CVCs who were receiving home-based chemotherapy, and it represents the second larger outbreak of CVCs-associated BSIs due to Klebsiella oxytoca in oncology outpatient centers. We retrospectively analyzed the chain of investigations and prophylactic/diagnostic measures taken to eradicate the infection: (1) patients' chart audit, (2) estimation of the infection among asymptomatic patients, (3) implementation of the level of awareness of medical and paramedical personnel, (4) collection of samples from environment, medications and infusion materials, (5) critical appraisal of chemotherapeutical schemes and (6) cooperation with peripheral institutions. The isolation of Klebsiella oxytoca in a chemotherapy solution (infusional 5-FU in dextrose 5% solution within a 48 h pump) from a peripheral General Hospital and the prompt transmission of the data to the chemotherapy center played a key role for the management of the infection cluster. This is the first report that evidenced the detection of Klebsiella oxytoca within a chemotherapeutical preparation. Data transmission from peripheral hospitals to the central institution resulted in an important feedback that allowed a better estimation of the infection cluster and more tailored actions for the eradication of the infection.

Summarization: There is a number of highway transportation infrastructures where traffic flow arriving on a higher number of lanes must merge into a lower number of lanes within a limited space, e.g., merging highways, merging on-ramps, toll plazas, work zones. When the arriving traffic flow exceeds the downstream capacity, congestion is formed, and the outflow is reduced due to the congest ion-induced capacity drop. A general conceptual framework for real-time merging traffic control is developed in the paper, aiming at throughput maximization or, equivalently, delay minimization. To this end, an algorithm known from local ramp metering operations is employed (ALINEA). The proposed framework is applied to new and innovative traffic control applications for real-time toll plaza and work zone management. Microscopic simulation results demonstrate the potentially achievable benefits. Further significant applications of the developed concept are outlined. (c) 2007 Elsevier Ltd. All rights reserved. Presented on: Transportation Research Part C: Emerging Technologies

Introduction Patients with human immunodeficiency virus carry a significant risk of contracting opportunistic infections. The worldwide increased incidence of tuberculosis has instituted pulmonary tuberculosis as an important diagnostic consideration in patients with human immunodeficiency virus presenting with lower respiratory tract infection. A positive result on the readily-available Ziehl-Neelsen stain usually leads to the initiation of antituberculous treatment, since tuberculosis may exert a rapid and even fatal clinical progress in human immunodeficiency virus coinfection. However, a number of other acid-fast bacteria might be implicated as offending pathogens. This case highlights the importance of broadening the list of pathogens that can account for a positive Ziehl-Neelsen stain in this select group of patients. Case presentation We describe the case of a 34-year-old, Albanian man with untreated human immunodeficiency virus, presenting with clinical and radiologic signs of pulmonary tuberculosis and a positive Ziehl-Neelsen sputum specimen, who was finally diagnosed with pulmonary infection by Rhodococcus equi. Conclusions Rhodococcus equi is a rare cause of pulmonary disease, even in patients with human immunodeficiency virus, and a positive Ziehl-Neelsen sputum specimen often misleads clinicians to more common organisms such as mycobacteria. A high index of suspicion, broadening the spectrum of optional pathogens, and effective communication between clinicians and microbiologists can ensure an efficient diagnostic and therapeutic approach.

Introduction: Peritonitis is a severe complication of peritoneal dialysis (PD) due to associated morbidity and mortality. Although Bacillus cereus is mostly considered as a contaminant, its role as a causative agent in a few cases of PD peritonitis has been documented. Peritonitis due to B. cereus has been associated with high rates of catheter removal and resistance to beta‐lactam antibiotics. Case presentation: A case of relapsing peritonitis caused by B. cereus in a 69‐year‐old man with end‐stage renal disease on continuous ambulatory PD for 3 years is described. B. cereus was recovered from the patient’s peritoneal fluid and was identified by phenotypic and molecular methods. The patient was treated, according to the susceptibility test, with tobramycin for 14 days. Cultures became sterile and the patient was discharged from hospital. Three days after discharge, the patient reported recurrence of abdominal pain and a new antibiotic regimen based on the previous culture results was initiated consisting of vancomycin and ciprofloxacin. The presence of B. cereus in the peritoneal fluid was confirmed, whereas repeated cultures for the next 15 days were positive. All B. cereus isolates produced biofilm. On day 16, the PD catheter was removed and the patient was transferred to haemodialysis. A review of previously reported cases is also presented. Conclusion: Since peritonitis is the most common cause of transition to haemodialysis, isolation of B. cereus from PD patients, even though rare, should not be considered as a contaminant. An appropriate antibiotic regimen and, whenever necessary, catheter removal should be applied.

Tinea unguium, known as onychomycosis, is a dermatophyte infection of nails with worldwide distribution. Conventional methods for detecting fungi in nail specimens are either non-specific (microscopy) or insensitive (culture). PCR has been used to improve sensitivity in detecting the causative fungi in nail specimens from patients with suspected onychomycosis. Results of a commercial multiplex PCR for the detection of dermatophytes, especially Trichophyton rubrum (the main dermatophyte implicated), as compared to conventional methods are presented. A total of 418 nail scrapings obtained from dermatological outpatients were handled in the Laboratory of Microbiology between May 2010 and May 2013. Among them, multiplex PCR detected 126 (30.1 %) dermatophyte-positive samples, whereas culture revealed 44 (10.5 %). Direct microscopy revealed 63 (15.1 %) positive specimens. T. rubrum was identified in 116 out of 126 (92 %) positive PCR samples and 40 out of 44 (91 %) dermatophyte-positive cultures. Implementation of PCR increased species-specific detection of dermatophytes by 21.1 %, leading to a threefold increase as compared to culture alone. Multiplex PCR offers a time-saving diagnostic tool for tinea unguium and augments laboratory assistance to clinical evaluation for proper treatment.

Toxoplasmosis is the most common opportunistic infection of the central nervous system in immunosupressed patients. It is usually presented as a space-occupying lesion detected by cerebral computerized tomography or magnetic resonance imaging. The diffuse form of the disease (diffuse toxoplasmic meningoencephalitis) lacks the characteristic cerebral radiologic findings rendering pre-mortem diagnosis much more difficult. Herein, we describe a case of toxoplasmic menincoencephalitis, without evidence of cerebral space-occupying lesions, in a patient with ulcerative colitis under combined therapy with systemic glucocorticoids and azathioprine. Diagnosis was based on microscopic examination of cerebrospinal fluid (CSF) for the parasite, whereas, RT-PCR for Toxoplasma gondii was negative. Taking into consideration the limitations of molecular methods, investigation of the etiology of meningeal involvement in patients under immunosuppressive therapy presenting positive serology of previous T. gondii infection, should include microscopic examination of CSF for parasite presence.

Acinetobacter baumannii has emerged as an important and problematic pathogen causing bloodstream infections (BSI) in hospitalized patients. Results of an 8-year period from a university hospital are presented. Identification of A. baumannii was performed by Gram-negative BD BBL Crystal ID and VITEK(®)2 system, whereas, susceptibility testing by VITEK2, Kirby-Bauer disc system, and Etest strips. Interpretation of results was based on CLSI criteria and, regarding tigecycline, Food and Drug Administration (FDA) criteria. Between 2006 and 2013, 441 among 7088 BSI cases were attributed to A. baumannii. Of all isolates, 92·1% were resistant to more than three classes of antibiotics and 79·4% were resistant to all but one or two categories of antimicrobials. Resistance to ampicillin-sulbactam, meropenem, gentamicin, ciprofloxacin, minocycline, and tigecycline increased during the study period (P0·05). Although tigecycline resistance was low during the first 4 years of the study (25·5%), it increased up to 66·5% during 2010-2013. No isolate was colistin resistant.

Summarization: This paper investigates the application of real-time route diversion policies in the case where recurrent motorway traffic congestion is created due to a saturated off-ramp. In particular, the proposed route diversion policies attempt to avoid the off-ramp queue spill-over onto the motorway mainstream and the resulting motorway congestion by re-routing the motorway vehicles through nearby off-ramps towards the same destination. In particular, this paper addresses the case where real-time route guidance strategies, based on user-optimum considerations, are sufficient to resolve the spill-over and motorway congestion problem; while other cases are treated in a companion paper. The proposed route guidance concepts are tested for a hypothetical but quite typical network infrastructure and traffic scenario by use of macroscopic simulation. The obtained simulation results are compared to the case where no route guidance is applied to the network and reveal interesting features and the potential for significant improvements. Παρουσιάστηκε στο: ence on I6 th International IEEE Annual Conferntelligent Transportation Systems

Work zones on motorways necessitate the drop of one or more lanes which may lead to significant reduction of traffic flow capacity and efficiency, traffic flow disruptions, congestion creation, and increased accident risk. Real-time traffic control by use of green-red traffic signals at the motorway mainstream is proposed in order to achieve safer merging of vehicles entering the work zone and, at the same time, maximize throughput and reduce travel delays. A particular issue addressed in this research is the investigation of the appropriate distance between the merge area and the traffic lights so as to lead, in combination with the employed real-time traffic control strategy, to the most efficient merging of vehicles. The control strategy applied for real-time signal operation is an ALINEA-like PI-type feedback regulator. In order to achieve maximum performance of the control strategy, some calibration of the regulator's parameters may be necessary. The calibration is first conducted manually, via a typical trial-and-error procedure. In an additional investigation, the recently proposed learning/adaptive algorithm AFT is employed in order to automatically fine-tune the regulator parameters. Experiments conducted with a microscopic simulator for a hypothetical work zone infrastructure, demonstrate the potential high benefits of the control scheme., Procedia-Social and Behavioral Sciences, 48, ISSN:1877-0428

Evaluation of epidemiological trends, risk factors, and clinical outcome associated with candidemia at a neonatal intensive care unit is reported. From January 2005 to December 2009, forty candidemia cases were identified. C. albicans and C. parapsilosis were the most common species recovered (69 and 24%, respectively). All C. parapsilosis strains were susceptible to antifungals, whereas, C. albicans exhibited higher resistance rates to azoles. Low birth weight, low gestational age, presence of central lines, endotracheal intubation, total parenteral nutrition, previous use of antibiotics, steroids, previous episode(s) of bacteremia and prolonged stay in intensive care unit were common features associated with candidemia. C. albicans was most often isolated from extremely low birth weight neonates as compared to non-albicans Candida (P 0.01). Mortality rate was 35.7% and was associated with low gestational age (P 0.01), low birth weight (P 0.01), and presence of renal failure (P 0.05). Furthermore, a critical review of recent published case series is presented.

The extracellular slime of Staphylococcus epidermidis contains, amongst various macromolecules, an acidic polysaccharide (PS) of a molecular mass of 20 kDa with significant antigenic and biological properties. The isolation procedure used so far includes multiple fractionations in anion-exchange chromatographic columns before its final purification by gel filtration chromatography. This protocol is laborious, time-consuming and includes the risk of unnecessary loss of PS quanti- ties. Because of the significance of this PS, a modified protocol resulting in an easier and quicker isolation procedure was developed. Furthermore, identification, purity, charge density and molecular integity of the isolated polysaccharide were evaluated by a reverse-polarity capillary electrophoresis method. Copyright © 2010 John Wiley & Sons, Ltd.

J Lab Clin Med

Summarization: This paper investigates the application of real-time route diversion policies, with or without off-ramp closure, to address recurrent motorway traffic congestion created due to a saturated off-ramp. In particular, the proposed route diversion policies attempt to avoid the off-ramp queue spill-over onto the motorway mainstream and the resulting motorway congestion by re- routing the motorway vehicles through nearby off-ramps towards the same destination. This paper addresses the case where real-time route guidance strategies, based on user-optimum considerations, are not sufficient to resolve the spill-over and motorway congestion problem, which may call for harsh measures (off-ramp closure) to force route diversion; while other cases are treated in a companion paper. The proposed route diversion concepts are tested for a hypothetical, but quite typical network infrastructure and traffic scenario by use of macroscopic simulation. The obtained simulation results are compared to the case where no route diversion is employed, and reveal interesting features and the potential for significant improvements. Παρουσιάστηκε στο: 16 th Meeting of the EURO Working Group on Transportation

The aim of this study was to investigate the isolation and distribution rate of Candida spp. in blood cultures and evaluate antifungal susceptibility during an 11-year period (1998–2008) at a tertiary-care hospital. The causative species were as follows: Candida albicans, 163 strains (64%); Candida parapsilosis, 35 strains (13.7%); Candida glabrata, 25 strains (9.8%); Candida tropicalis, 19 strains (7.4%); and other Candida spp., 13 strains (5.1%). Candidaemia is predominantly caused by C. albicans. C. parapsilosis is the most common non-albicans Candida isolated in neonatal intensive-care units. All Candida isolates remain susceptible to amphotericin B, whereas the highest degree of resistance was observed for azoles.

Summarization: A simple real-time merging traffic control concept is proposed for efficient toll plaza management in cases where the total flow exiting from the toll booths exceeds the capacity of the downstream highway (or bridge, or tunnel), leading to congestion and reduced efficiency due to capacity drop. Merging traffic control aims at maintaining the number of vehicles in the merge area close to a critical value that maximizes throughput; to this end, an algorithm known from local ramp metering operations is proposed (ALINEA). The potential control concept efficiency is demonstrated by use of microscopic simulation applied to a particular toll plaza infrastructure with and without merging traffic control. It is shown that the employed feedback regulator is little sensitive to various settings which indicates easy applicability with low fine-tuning needs in potential field applications. The case of partially uncontrolled lanes (e.g., for high-occupancy vehicles, buses or other vehicles) is also addressed. Παρουσιάστηκε στο: 10th International Conference on Application of Advanced Technologies in Transportation