This case demonstrates, as do the 3 others reported in literature, that a diagnosis of malignant atrophic papulosis can only be made once the possibility of a lupus erythematosus has been totally excluded.
Biopsies were taken from psoriatic patients undergoing photochemotherapy and then studied by autoradiography to investigate possible unscheduled DNA synthesis (UDS) following 8-MOP photodamage in epidermal cels. No sparse labelling was found in seventy samples taken from twenty-four different patients during PUVA therapy, indicating a lack of UDS. In contrast, UDS was observed in three patients irradiated with an all-spectrum UV lamp, as a test for DNA damage and excision repair activity. The incorporation of 3HTdR in these keratinocytes which were not undergoing S-phase was not affected by the dose of UV-A received during different stages of PUVA treatment. The results are discussed in terms of repair of the induced photodamage at the level of DNA, and in relation to a possible risk of this treatment when it is given over a long period of time.
An ultrastructural examination was carried out on the skin of six children suffering from Mucopolysaccharidosis I (MPSI or Hurler's disease) and MPS II (Hunter's disease). Both intracellular mucopolysaccharides and lipids were observed. The dermal cells, i.e. fibroblasts, macrophages, were loaded with multiple vacuolar inclusions thought to be of lysosomal origin. They appeared either content-free or filled with granular, fuzzy and/or pseudomyelinic structures. Identical abnormalities were observed within the Schwann cells, smooth muscle cells and keratinocytes. Mast cells showed peculiar "worm-like" inclusions apart from their normal granulations. Since ultrastructure of a skin sample may provide as much data as brain, liver or kidney, cutaneous electron microscopy can be recommended to confirm a diagnosis of MPS.
The principal reported morphological consequence of portacaval shunt in the rat is liver atrophy. The present study was designed to investigate ultrastructural changes in hepatocytes using electron microscopy morphometry. Two weeks following portacaval shunt, rat livers were fixed by perfusion and hepatocyte organelles from the two opposite zones of the acinus (zones 1 and 3) were quantified. Liver weight/body weight decreased by 50%, hepatocyte-specific volume decreased by 30% (28% in zone 1 nd 35% in zone 3). Estimated sinusoidal space increased, and estimated number of hepatocytes decreased by 50%. Hepatocytes had a normal ultrastructure except for mitochondria. Smooth endoplasmic reticulum-specific surface area was reduced by 65% (zone 3), and rough endoplasmic reticulum surface density was increased in zone 1 only. Mitochondria-specific volume was unchanged but decreased inner and outer membrane-specific surface area in zone 3 suggests in this zone a change in their conformation and possibly their number. Golgi-rich area surface density increased but not significantly. Hepatocyte loss and atrophy and rearrangement of organelles represent a new ultrastructural steady state following portacaval shunt that may help explain the new functional steady state.
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