Comparative studies on growth kinetics of cultivated human hair bulb papilla cells (PCs) and hair root sheath fibroblasts (RSFs) yielded evidence of some peculiarities of PCs in both proliferative behavior and morphological growth pattern. As the dermal papilla, essentially supporting the nutrition of matrix epithelium, can be considered a target tissue for agents influencing maintenance of hair growth, we studied the effects of epidermal growth factor (EGF), fibroblast growth factor (FGF), minoxidil (Mino), and hydrocortisone (HC) on the proliferation of PCs and RSFs, both gained from dissected hair follicles of scalp biopsy specimens of two male adults and separately cultured in vitro. EGF and FGF proved to increase proliferation of both PCs and RSFs most, yet at a different intensity for each cell group. HC slowed proliferation, and Mino failed to influence growth of PCs and RSFs.

Dermal papillae isolated from anagen hair bulbs obtained from biopsy specimens from five subjects with normal hair pattern, and fibroblasts derived from the mesenchymal root sheaths (RSF) of the same hair follicles were separately grown in culture and the cell-cycle distribution pattern on different days was analyzed by applying DNA flow cytometry (FCM). Papilla cells (PC) exhibited distinctive morphological features by forming cell aggregates differing from RSF with respect to cell shape and growth pattern. They also proliferated remarkably more slowly than RSF. DNA-FCM analysis showed that both PC and RSF demonstrated synchronous fluctuations in the percentage of cells in G1/0, S and G2 + M phases during the period of subculture.

No abstract

Before clinical application of an extracorporeal piezoelectric lithotripter to treat sialolithiasis, tissue reaction during shockwave application was examined in vitro and in experiments with animals. Application of shockwaves to human tissue in vitro showed neither macroscopic nor microscopic effects. In animal experiments, the acute experiment (16 rabbits, Chinchilla-Bastard) revealed minor bleeding in the parenchyma of the parotid gland, while the chronic experiment (14 rabbits, Chinichilla-Bastard) revealed no morphologic tissue damage to the parotid region of the rabbit, as a result of piezoelectric shockwaves. However, when the eye was placed in the shockwave focal area and the shockwaves were transmitted via the fissura orbitalis to the endocranium, brain damage could be detected morphologically. In conclusion, the authors feel that the clinical application of extracorporeal piezoelectric fragmentation of salivary stones is justified, provided that a reliable positioning of the patient and exact sonographic location of the concrement are possible.

No abstract