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A study relating to research on the structure and properties of dendrimers was conducted to investigate the influence of solvents on the hydrodynamical volume of dendrimers. Specifically, a fluorophore-labeled dendrimer with a rubicene derivative as a core was covalently linked to the dendrons and fluoresence depolarization was used to derive the hydrodynamical volume of this labeled dendrimer. The experiment and its results are discussed.

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There is a well-known association between improved endurance performance and lower cardiovascular risk, although the exact physiological mechanisms underlying this association have not been fully elucidated. To investigate this, 21 subjects completed a structured, 10- week, polarized and periodized running training program. Cardiovascular parameters were determined using lactate performance diagnostics, the salt-blood test (SBT)-mini as marker for the glycocalyx, and pulse wave analysis (PWA) at baseline and follow-up examinations. In addition, blood lipid and sugar levels, as well as blood pressure progression, were documented to provide information on the general health of the subjects.The main effects of the 10-week polarized and periodized running training were (i) an improvement in performance, (ii) reduced total and HDL cholesterol, (iii), lowered blood pressure, and (iv) a decrease in the augmentation index (p=0.012). For the entire cohort, the SBT mini values were not changed after the intervention. Interestingly, the improved vascular function correlated with greater performance gains for subjects under 45 yrs (r=-0.636; p=0.019 and r=-0.771; p=0.003). Here, we showed that polarized and periodized running training has positive effects on the vascular system, with the augmentation index being a suitable marker for early detection of vascular changes. Of note, only young subjects benefited from a greater increase in performance regarding vascular function. However, further investigations are needed to clarify whether this result is based on an age-dependent, longer regeneration time.Key Words: Physical Exercise, Glycocalyx, Pulse Wave Velocity, Cardiovascular Fitness

Background: Methicillin-resistant Staphylococcus aureus (MRSA)-USA300 is notorious for its ability to cause community- and healthcare-acquired infections, which are even more difficult to treat when associated with a biofilm phenotype. We aimed to characterize the genetic determinants of biofilm formation in a USA300 skin abscess isolate (UAS391) that formed prolific biofilms. Methods: USA300 S. aureus strains, TCH1516 and FPR3757, were found to be closely related based on whole genome mapping (Argus? Optical Mapping System, Opgen Inc, Gaithersburg, USA) to UAS391 (96.3-99.1% similarity, P=0.0151), however differed markedly in biofilm formation (P=0.0001) on a dynamic assay (BioFlux 200, Fluxion Biosciences, USA). Comparison of whole genome sequences of these strains identified differences in a total of 18 genes. Corresponding Tn (bursa aurealis-bearing) knockout mutants in these target genes were obtained from a publicly available mutant library of the same clonal lineage (USA300-JE2) and were characterized phenotypically for biofilm formation. Tn mutants showing significant differences in biofilm formation were utilized for transduction into a plasmid-cured erythromycin-sensitive derivative of UAS391 and for complementation experiments. All strains were tested on the dynamic assay, and 17h-biofilms were stained (SYTO9, Life Technologies) and fluorescence intensity quantified by microscopy (Zeiss, ImageJ). Gene expression levels in Tn and transduced mutants were studied by quantitative reverse transcriptase PCR (StepOnePlusTM, Applied Biosystems®). Results: Comparison of the sequenced genomes of TCH1516, FPR3757 and UAS391 yielded a limited number of variant genes (n=18) that were hypothesized to account for the observed difference in biofilm-forming capacity. Screening of Tn mutants disrupted in these target genes identified one mutant (NE229) bearing a transposon insertion in SAUSA300_1119 (fakA), which exhibited increased biofilm formation similar to UAS391 (P=0.9320). Transduction experiments confirmed that fakA::Tn corresponded to 1.9- to 4.6-fold increase in biofilm formation depending on the USA300 strain background (P≤0.0007), while complementation of the TCH1516 wild-type fakA allele in UAS391 resulted in a 4.3-fold reduction in biofilm formation (P<0.0001). Conclusions: This sequential approach, consisting of strain typing, genome comparison and functional genomics, identified fakA, a recently described fatty acid kinase in S. aureus that is essential for phospholipid synthesis and also impacts the transcription of numerous virulence factors, as a negative regulator of biofilm formation in S. aureus USA300. [ABSTRACT FROM AUTHOR]