Biomedical subjects

M Benci

Publications and source records attributed to M Benci.

8 recordsLinked to original sources

PubMed1995

Plasminogen activators, venous leg ulcers and reepithelialization.

BACKGROUND AND OBJECTIVE: The pathogenesis of leg ulcers due to chronic venous hypertension (CVH) seems to be related to perivenular fibrin-film formation due to decreased cutaneous fibrinolytic activity dependent on reduced release of tissue-type plasminogen activator that leads to tissue anoxia and ulcer formation. The purpose of the work is a spectrophotometric evaluation of urokinase (UPA) at the edge, the floor and in the periulcerous skin of leg ulcers. METHODS: We examined a group of 10 patients with chronic leg ulcers caused by CVH. The biopsies from each patient were taken: (1) from the edge of the ulcer; (2) from the perilesional skin and (3) from the floor of the ulcer. Urokinase levels were evaluated in the same areas in 10 control subjects. The UPA activity was determined spectrophotometrically at 405 nm. RESULTS: The results of our study showed that UPA is detectable in the center of the ulcer, on the edge, in the perilesional skin, as well as in the controls. Data are statistically significant. The highest levels of UPA are found at the edge of the ulcer; they were lower in the center and in the periulcerous skin. CONCLUSION: A chemoattracting effect of UPA on human keratinocytes has been documented and this study showed significantly higher levels of UPA at the edge and on the floor of the ulcers, suggesting a possible role of an UPA gradient that could promote mobilization of keratinocytes from the edge to the floor, thus inducing reepithelialization. Moreover, UPA could play some role in neoangiogenesis and fibroblast chemoattraction, thus contributing in various ways to wound healing.

Aged↗

PubMed1994

Ultrastructural study of hyaluronic acid before and after the use of a pulsed electromagnetic field, electrorydesis, in the treatment of wrinkles.

BACKGROUND: Treatment of wrinkles has become an increasing problem for dermatologists. Hyaluronic acid is a component of the family of glycosaminoglycans (GAGS, substances known for their property of retaining water), that significantly decreases with aging and in wrinkles. A new technique that uses a specific pulsed electromagnetic field, electrorydesis, has been introduced in the treatment of wrinkles associated with aging. The treatment is based on the reported in vitro effects of specific electromagnetic fields on fibroblast cultures (e.g., an increase in DNA synthesis and in the production of collagen and presumably also of GAGS). METHODS: The in vivo effects of the electromagnetic field on aged skin (3 subjects aged 50, 56 and 60 years), with particular focus on the ultrastructural modifications and GAGS amount before and after the treatment, were evaluated by electron microscope. RESULTS: The ultrastructural study (tissue stained with alcian blue) showed after treatment a significant increase (p < 0.005) of the electron-dense granules (corresponding to hyaluronic acid), located in collagen elastic fibers, and in the soluble matrix. This presumably leads to subsequent edema that was clinically evident after the treatment. CONCLUSIONS: These data suggest that the increased levels of GAGS and the subsequent edema of the dermis could explain at least in part the clinical changes observed after electrorydesis treatment (e.g., swelling and "disappearance" of the wrinkle).

Electromagnetic Fields↗

PubMed1993

Mesoglycan treatment restores defective fibrinolytic potential in cutaneous necrotizing venulitis.

BACKGROUND: Cutaneous necrotizing venulitis (CNV) is a clinical disorder associated with segmental inflammation and fibrinoid necrosis of the dermal venules. It usually presents clinically as palpable purpura, even sometimes as nodules, bullae, ulcers, and urticarial lesions. This form, when showing as leukocytoclastic vasculitis is apparently characterized by the tissue deposition of circulating immune complexes and by reduced cutaneous (CFA) and plasma (PFA) fibrinolytic activity due to reduced release of plasminogen activator (PA) from the venular endotheliocytes. Reduced CFA and PFA cause large amounts of fibrin deposits in both intra- and perivascular areas, which are able to magnify and self perpetuate the inflammatory processes following immune complex deposition. METHODS: We have studied both the PFA and CFA potential (the maximum amount of PA released in the skin after certain stimuli) and the deposits of immunoglobulins, C3, and fibrin related antigen, before and after intradermal injection of histamine (a substance able to provoke endothelial release of PA), in three subjects affected by CNV before and 20 days after 10 mg/kg/day I.M. treatment with the fibrinolytic agent mesoglycan. RESULTS: Cutaneous fibrinolytic activity and CFA potential, reduced prior to treatment, was normal after treatment, while the deposits of immunoglobulins (IgA, IgG and IgM), C3, and fibrin related antigen, detected with direct immune fluorescence (DIF) showed similar findings before and after treatment. CONCLUSIONS: These data suggest that reduced CFA may play a major role in the pathogenesis of the immunologically mediated injury in CNV. The intraperivascular deposition of fibrin is favored. The fibrinolytic agent mesoglycan seems effective in restoring defective fibrinolysis in patients affected by cutaneous necrotizing venulitis, suggesting that in cases with reduced cutaneous fibrinolytic activity (or potential) the use of a fibrinolytic agent should be considered.

Adult↗

PubMed1993