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To prevent implant-associated infections, surface modifications need to be developed that prevent bacterial colonisation and biofilm formation. In the present study, titanium surfaces were processed by nanosecond-pulsed laser ablation to generate a variety of different structures (anatase, rutile, Osteon, as well as Osteon additionally coated with silver and clove nanoparticles). Analysis of adhesion and biofilm formation of the oral pioneer bacterium Streptococcus oralis could demonstrate antibacterial properties of anatase surfaces. For clinical translation, the effect should be enhanced by further adaption and combined with the osseointegrative Osteon structure

Uridine phosphorylase (UP; EC 2.4.2.3), a key enzyme in the pyrimidine-salvage pathway, catalyzes the reversible phosphorolysis of uridine to uracil and ribose 1-phosphate. The structure of the C212S mutant of uridine phosphorylase from the facultatively aerobic Gram-negative γ-proteobacterium Shewanella oneidensis MR-1 (SoUP) was determined at 1.68 Å resolution. A comparison of the structures of the mutant and the wild-type enzyme showed that one dimer in the mutant hexamer differs from all other dimers in the mutant and wild-type SoUP (both in the free form and in complex with uridine). The key difference is the `maximum open' state of one of the subunits comprising this dimer, which has not been observed previously for uridine phosphorylases. Some conformational features of the SoUP dimer that provide access of the substrate into the active site are revealed. The binding of the substrate was shown to require the concerted action of two subunits of the dimer. The changes in the three-dimensional structure induced by the C212S mutation account for the lower affinity of the mutant for inorganic phosphate, while the affinity for uridine remains unchanged. [ABSTRACT FROM AUTHOR]

Abstract: The on-line control procedure of laser cleaning process based on optical emission spectroscopy is proposed in the article. The spectral indication of non-destructive laser cleaning of laser-engraved rolls enabling to keep a surface texture for the purposes of maximum effect of cleaning is revealed. [Copyright &y& Elsevier]

Abstract Background Apical periodontitis (AP) is an inflammatory disease around the apex of a tooth root. Reported prevalence of AP ranges from 27% to 83% while the data about most post-Soviet countries are still missing. Knowing the prevalence of AP within a certain population helps to plan the treatment need and evaluate the success of endodontic interventions. We aimed to collect data about prevalence and determining factors of AP for the first time in Estonia. Methods The cross-sectional study included 6552 patients (age 35.5±19.2 years). Radiographic examination was applied to investigate the prevalence of AP and quality of endodontic treatment. Results AP was diagnosed in 54.7% of subjects. Endodontically treated teeth were present in 58.2% of subjects. Periapical finding was present in 44.6% of endodontically treated and in 30.8% of untreated teeth. Out of 181,495 teeth, 52.7% were intact. AP was diagnosed in 6.3% of teeth, 6.9% of teeth were endodontically treated. Risk factors for AP included caries (OR = 2.30), male gender (OR = 1.44), too short (OR = 1.76) or too long root canal filling (OR = 2.51), root canal filling of low density (OR = 1.61) while not orthodontic appliance. Lower AP risk was associated with restoration of the tooth – filling (OR = 0.45), crown (OR = 0.34) and bridge (OR = 0.33). Conclusions AP is highly prevalent in Southern Estonian population. Most cases are associated with root canal-treated teeth. The overall quality of root canal fillings tends to be low, consistent with the mediocre outcome of treatment. Considerable efforts are required to improve the standards of endodontic treatment.