Skin color independent assessment of aging using skin autofluorescence

Skin autofluorescence (AF) for the non-invasive assessment of the amount of accumulated tissue Advanced Glycation Endproducts (AGEs) increases with aging. In subjects with darker skin colors, measurements typically result in lower AF values than in subjects with fair skin colors, e.g. due to selective absorption by skin compounds. Our aim was to provide a new method for calculating skin AF, yielding values that are independent of skin color. The deviation of skin AF of healthy subjects with various darker skin types (N = 99) compared to reference values from Caucasians showed to be a function of various parameters that were derived from reflectance and emission spectra in the UV and visible range (adjusted R(2) = 80%). Validation of the new algorithm, based on these findings, in a separate dataset (N = 141) showed that results of skin AF can now be obtained to assess skin AGEs independently of skin colo

The significance of peroxisomes in secondary metabolite biosynthesis in filamentous fungi

Peroxisomes are ubiquitous organelles characterized by a protein-rich matrix surrounded by a single membrane. In filamentous fungi, peroxisomes are crucial for the primary metabolism of several unusual carbon sources used for growth (e.g. fatty acids), but increasing evidence is presented that emphasize the crucial role of these organelles in the formation of a variety of secondary metabolites. In filamentous fungi, peroxisomes also play a role in development and differentiation whereas specialized peroxisomes, the Woronin bodies, play a structural role in plugging septal pores. The biogenesis of peroxisomes in filamentous fungi involves the function of conserved PEX genes, as well as genes that are unique for these organisms. Peroxisomes are also subject to autophagic degradation, a process that involves ATG genes. The interplay between organelle biogenesis and degradation may serve a quality control function, thereby allowing a continuous rejuvenation of the organelle population in the cells

Improving the measurement of skin autofluorescence, or: working on the clinical applicability of skin autofluorescence from a biomedical engineering perspective

The detection of an increased risk of cardiovascular diseases is important in preventive health care. The measurement of autofluorescence (AF) of the skin with an AGE reader is a non-invasive and fast method for the assessment of advanced glycation end products (AGEs). AGEs are metabolic products that accumulate in tissues with low collagen turn-over, such as skin. Their amount is an independent predictor of cardiovascular risk. Many measurements of skin were performed in healthy subjects to assess age-dependent reference values in a Caucasian population. A new calculation method was developed for skin AF measures in people with dark skin. The method of AGE-measurement was also reliable in patients who are using haemodialysis.

Skin and Plasma Autofluorescence During Hemodialysis: A Pilot Study

Skin autofluorescence (AF) is related to the accumulation of advanced glycation end products (AGEs) and is one of the strongest prognostic markers of mortality in hemodialysis (HD) patients. The aim of this pilot study was to investigate whether changes in skin AF appear after a single HD session and if they might be related to changes in plasma AF. Skin and plasma AF were measured before and after HD in 35 patients on maintenance HD therapy (nine women and 26 men, median age 68 years, range 33-83). Median dialysis time was 4h (range 3-5.5). Skin AF was measured noninvasively with an AGE Reader, and plasma AF was measured before and after HD at 460nm after excitation at 370nm. The HD patients had on average a 65% higher skin AF value than age-matched healthy persons (