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The etiology of diabetic foot ulceration remains incompletely understood. Among other factors such as foot deformity in the presence of neuropathy, plantar fat pad atrophy has been identified as a contributory factor in diabetic foot ulceration. An association between fat pad atrophy and diabetic foot ulceration has been documented by imaging and histomorphological analysis of the calcaneal fat pad. However, histomorphological analysis of the metatarsal fat pad has not been performed to date. The present study entailed 14 patients with diabetes and 14 nondiabetic controls and was aimed at documenting histomorphological evidence for presumed plantar metatarsal fat pad atrophy in patients with diabetes. Histological stains and computer-assisted planimetry were performed on samples of metatarsal fat obtained during forefoot surgery. The histomorphological and planimetric analyses of adipocyte cross-sectional area and nuclear density demonstrated no differences between patients with diabetes and control patients. Our findings demonstrate that systemic atrophy of the metatarsal fat pad is not present in the diabetic foot and may not explain the structural changes previously proposed by noninvasive imaging. Level of Clinical Evidence: 3. [ABSTRACT FROM AUTHOR]

Abstract: Ramalina maciformis and Ramalina lacera were exposed to different solutions and UV-B to seek for alterations in the PSII photosynthetic quantum yield (F v/F m), in response to chemicals and radiation. For R. maciformis, significant alterations of the F v/F m ratio occurred only in response to different bisulphite solutions. The F v/F m ratio decreased most in R. maciformis and R. lacera following exposure to 5 and 1mM bisulphite, respectively. Significant differences in F v/F m ratios were observed for R. lacera in response to different solutions and light at different wavelengths, this being synergistic. The PSII system was unaffected by simulated acid rain in both lichens. R. maciformis, in particular, may survive limited acid rain exposure owing to high Ca oxalate accumulation. The F v/F m ratio decreased most in R. lacera following short-term exposures to CuSO4, suggesting that this species is more sensitive to Cu ions under acidic conditions. [Copyright &y& Elsevier]

Abstract: Photodynamic therapy (PDT) with Visudyne® acts by direct cellular phototoxicity and/or by an indirect vascular-mediated effect. Here, we demonstrate that the vessel integrity interruption by PDT can promote the extravasation of a macromolecular agent in normal tissue. To obtain extravasation in normal tissue PDT conditions were one order of magnitude more intensive than the ones in tissue containing neovessels reported in the literature. Fluorescein isothiocyanate dextran (FITC-D, 2000kDa), a macromolecular agent, was intravenously injected 10min before (LK0 group, n =14) or 2h (LK2 group, n =16) after Visudyne®-mediated PDT in nude mice bearing a dorsal skin fold chamber. Control animals had no PDT (CTRL group, n =8). The extravasation of FITC-D from blood vessels in striated muscle tissue was observed in both groups in real-time for up to 2500s after injection. We also monitored PDT-induced leukocyte rolling in vivo and assessed, by histology, the corresponding inflammatory reaction score in the dorsal skin fold chambers. In all animals, at the applied PDT conditions, FITC-D extravasation was significantly enhanced in the PDT-treated areas as compared to the surrounding non-treated areas (p <0.0001). There was no FITC-D leakage in the control animals. Animals from the LK0 group had significantly less FITC-D extravasation than those from the LK2 group (p =0.0002). In the LK0 group FITC-D leakage correlated significantly with the inflammation (p <0.001). At the selected conditions, Visudyne®-mediated PDT promotes vascular leakage and FITC-D extravasation into the interstitial space of normal tissue. The intensity of vascular leakage depends on the time interval between PDT and FITC-D injection. This concept could be used to locally modulate the delivery of macromolecules in vivo. [Copyright &y& Elsevier]