Production of proteolytic enzymes in mast cells, fibroblasts, vascular smooth muscle and endothelial cells cultivated under normoxic or hypoxic conditions.

Matrix metalloproteinases (MMPs) is a family of proteolytic enzymes involved in remodeling of extracellular matrix. Although proteolytic enzymes are produced by many cell types, mast cells seem to be more important than other types in remodeling of pulmonary arteries during hypoxia. Therefore, we tested in vitro production of MMPs and serine proteases in four cell types (mast cells, fibroblasts, vascular smooth muscle cells and endothelial cells) cultivated for 48 h under normoxic or hypoxic (3% O2) conditions.

Dymanics of matrix-metalloproteinase 9 after brain trauma--results of a pilot study.

Background: Secondary brain injury contributes to poor outcome for patients sustaining brain trauma. Matrix metalloproteinase-9 (MMP-9) is a potential marker, as well as effector of secondary brain injury. This enzyme degrades components of extracellular matrix, and thus it can contribute to blood-brain barrier disruption.

In vitro hypoxia increases production of matrix metalloproteinases and tryptase in isolated rat lung mast cells.

Chronic hypoxia results in hypoxic pulmonary hypertension characterized by fibrotization and muscularization of the walls of peripheral pulmonary arteries. This vessel remodeling is accompanied by an increase in the amount of lung mast cells (LMC) and the presence of small collagen cleavage products in the vessel walls. We hypothesize that hypoxia activates LMC, which release matrix metalloproteinases (MMPs) cleaving collagen and starting increased turnover of connective tissue proteins.

Role of oxidative stress in PKC-delta upregulation and cardioprotection induced by chronic intermittent hypoxia.

The aim was to determine whether increased oxidative stress during the adaptation to chronic intermittent hypoxia (CIH) plays a role in the induction of improved cardiac ischemic tolerance. Adult male Wistar rats were exposed to CIH in a hypobaric chamber (7,000 m, 8 h/day, 5 days/wk, 24-30 exposures). Half of the animals received antioxidant N-acetylcysteine (NAC; 100 mg/kg) daily before the exposure; the remaining rats received saline.

Inhalation trauma in burns, cytology and biochemical findings.

We have followed in a pilot study a group of patients for cytological and biochemical changes of lavage in the upper and lower respiratory system. Into the study patients with respiratory burns confirmed by bronchoscopy and skiagraphy were included. We divided patients according to the Lung Injury Scores (LIS).