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Mihai Mareș,1,* Valentina-Ruxandra Moroti-Constantinescu,2,3,* Luminița Voroneanu,4,5 Florica Doroftei,6 Adrian Covic,4,5 Ovidiu-Alexandru Mederle71Laboratory of Antimicrobial Chemotherapy, Ion Ionescu de la Brad University, Iași, Romania; 24th Department, “Matei Balș” National Institute of Infectious Diseases, Bucharest, Romania; 3Department of Infectious Diseases, “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania; 4Department of Nephrology, “Gr. T. Popa” University of Medicine and Pharmacy, Iași, Romania; 5Renal Transplantation Center, “C. I. Parhon” Clinical Hospital, Iași, Romania; 6Intelcentru, “Petru Poni” Institute of Macromolecular Chemistry, Iași, Romania; 7Department of Microscopic Morphology/Histology, Angiogenesis Research Center, “Victor Babeș” University of Medicine and Pharmacy, Timișoara, Romania*These authors contributed equally to this workAbstract: The first case of invasive pulmonary infection due to the thermophilic fungus Thermoascus crustaceus in a kidney transplant recipient is described. For the identification of the fungal isolate, morphological aspects and molecular analysis have been used. The case report emphasizes this fungal species as an opportunistic human pathogen and underlines the importance of an accurate laboratory diagnosis for the correct management of the patient.Keywords: Thermoascus crustaceus, thermophilic fungi, pulmonary infection, caspofungin, immunosuppression

Gheorghe G Bălan,1 Irina Roşca,2 Elena-Laura Ursu,2 Florica Doroftei,2 Andra-Cristina Bostănaru,3 Eugen Hnatiuc,4 Valentin Năstasă,3 Vasile Şandru,5 Gabriela Ştefănescu,1 Anca Trifan,1 Mihai Mareş3 1Grigore T. Popa University of Medicine and Pharmacy, Iaşi, Romania; 2“Petru Poni” Institute of Macromolecular Chemistry, Iaşi, Romania; 3Ion Ionescu de la Brad University of Agricultural Sciences and Veterinary Medicine of Iasi, Iaşi, Romania; 4“Gheorghe Asachi” Technical University, Iaşi, Romania; 5Department of Gastroenterology Research, Clinical Emergency Hospital of Bucharest, Bucharest, Romania Introduction: Duodenoscopes have been widely used for both diagnostic and therapeutic endoscopic retrograde cholangiopancreatography procedures. Numerous outbreaks of duodenoscope-associated infections involving multidrug-resistant bacteria have recently been reported. Plasma activated water (PAW) has been widely considered an effective agent for surface decontamination and is increasingly used for disinfection of medical equipment. The aim of this study was to evaluate whether the duodenoscopes currently on market are suited for the repeated use of PAW and to test the efficacy of PAW for their disinfection. Materials and methods: In order to evaluate the disinfection efficacy and the required time of contact, the duodenoscope samples were contaminated by immersing them in fasted-state simulated intestinal fluid containing Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa, prior to PAW exposure. In order to test the duodenoscope polymer compatibility with PAW, a challenge test was conducted by immersing the samples in PAW for 30 minutes daily for 45 consecutive days. Results: Significant reductions in bacterial populations were achieved after 30 minutes of PAW treatment, indicating a high-level disinfection. Atomic force microscopy and scanning electron microscopy were used to demonstrate that repeated PAW treatment of duodenoscope coating polymer samples did not result in significant differences in morphological surface between the treated and untreated samples. Energy-dispersive X-ray spectroscopy analysis also showed no significant differences between the elemental composition of the duodenoscope coating polymer samples before and after repeated PAW treatment. Conclusion: Considering these preliminary results, PAW could be considered as a new alternative for duodenoscope reprocessing. Keywords: PAW, antibacterial activity, duodenoscope, disinfection

Polydimethylsiloxane-α,ω-diol was used as matrix for the preparation of polysiloxane-SiO2-TiO2 composites through in situ incorporation of silica and titania using a solvent-free sol-gel procedure. For this purpose, oxide precursors tetraethyl-orthosilicate and tetrabutyl-orthotitanate, and a proper condensation catalyst, viz. dibuthyltin dilaurate, were added in pre-established amounts to the polymer. The hydrolysis and condensation reactions take place under mild conditions, with the formation of silicon and titanium oxide networks and polymer crosslinking. The effect of SiO2 and TiO2 mass ratio on the morphology of the composites was investigated by scanning electron microscopy (SEM) and X-rays diffraction (XRD), and interpreted in correlation with differential scanning calorimetry (DSC) and energy-dispersive X-ray spectroscopy (EDX) data. The film samples were tested as active elements in actuation devices. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis and characterization of seven nanostructured NiFe2O4 ferrite samples with spinel type structure were studied. The samples were synthesized by the sol–gel autocombustion method, using cellulose, a cellulose–citric acid mixture, hexamethylenetetramine, citric acid, tartaric acid, glycine and urea as chelating/fuel agents. For the first time in the nickel ferrite synthesis developed by this method, hexamethylenetetramine and tartaric acid were used as chelating/fuel agents. The as-obtained samples were characterized by IR spectroscopy, XRD SEM and BET techniques. The catalytic properties of nanostructured NiFe2O4 samples were tested for hydrogen peroxide decomposition. The influence of chelating/fuel agents was highlighted in terms of combustion process development with consequences on particle size, interionic distance values, surface area, microstructure and catalytic activity. The best catalytic properties were recorded for NiFe2O4 obtained with urea as a chelating/fuel agent. [Copyright &y& Elsevier]

Abstract: Lignin use in polymer industry has recently become very attractive from both economical and environmental reasons. In the specific case of blending, the addition of low lignin amounts was found to improve the properties and extends the application field of other natural or synthetic polymers, but the effects of oxidative enzymes on resulting blends are widely unknown. Thereby, the current study was carried out to determine some potential effects of small flax lignin concentrations (4.2 and 9.3wt%) on the enzymatic degradation of a poly(ethylene adipate) urethane (PU). Thin cast films of PU and its lignin blends were incubated for 3 days at 30°C with buffered solutions of fungal peroxidase and laccase extracted from Aspergillus sp., and compared with the untreated ones. Changes in surface structure and morphology were investigated by attenuated total reflectance–Fourier transform infrared spectroscopy (ATR–FTIR) and scanning electron microscopy (SEM), while the impact on bulk was assessed from tensile tests and thermogravimetry analysis (TGA). Although the addition of flax lignin reduces the surface structural modifications after enzyme treatment, the morphology, tensile and thermo-oxidative characteristics are still affected, with laccase showing the higher degradative efficiency. The lignin concentration, its high impact on the resulting blends morphology and relative low resistance to laccase and peroxidase degradation was the most important factors proved to driven the enzymatic oxidation. [Copyright &y& Elsevier]

Hollow microcapsules composed from a natural polyelectrolyte and a protein were obtained using the layer-by-layer adsorption on silica oxide particles as template. For the first time, monobasic curdlan phosphate (PCurd) is used as anionic partner in self-assembled multilayers fabrication. The deposition of (curdlan phosphate /hydrolyzed collagen) multilayers was monitorized by ζ - potential measurements. The microparticles morphology assembled with four double-layers were investigated by optical and electron microscopy techniques, and atomic force microscopy. The hollow microcapsules obtained by the removal of the colloidal template with hydrofluoric acid solution were characterized by SEM-EADX and termooxidative analyses. [ABSTRACT FROM AUTHOR]