Chronic obstructive pulmonary disease and oxidative stress.

The respiratory tract as the main entrance for various inhalative substances has great potential to generate reactive species directly or indirectly in excess. Thus, heavy smokers are at high risk for development, impairment and failed response to treatment of chronic obstructive pulmonary disease (COPD). The article is an update regarding the influence of reactive oxygen (ROS) and nitrogen (RNS) species on COPD; however, we do not intend to describe ROS and RNS actions on the entire lung tissue. Here, we focus on the airways, because in human most of the described effects of ROS and RNS species are measured on respiratory epithelial cells obtained by bronchoscopy. ROS and RNS species are physiological compounds in cells and risk factors for several respiratory diseases. In general, both kinds of species are thermodynamically stabile, but their reaction behaviors in cellular environments are very different. For example, the life times of the superoxide anion radical range from micro/milliseconds up to minutes and even hours in in-vitro model systems. Oxidative stress by cigarette smoke was investigated in detail by the authors of this article. In addition, original studies by the authors on the amount of fine particulate matter and trace elements in lung biopsies after defined inhalation indicate a distortion of the equilibrium between oxidants and antioxidants. We also try to present some modern views with respect to genomic medicine for future therapeutic perspectives, although this is an upcoming sector of COPD therapy.

[Sense and nonsense in antibiotic therapy for respiratory tract infections]. / Sinn und Unsinn der Antibiotikatherapie respiratorischer Infekte.

Whether an antibiotic successfully eradicates pathogens depends on the pathogens involved, on pharmacokinetics and bioavailability in the target tissue, and on the antimicrobial resistance of the pathogen. Other determinants are drug interactions, individual risk factors, age and compliance with respect to correct dosage and duration of therapy. In many cases, antimicrobial therapy is begun on an empirical basis, because the responsible pathogen can be identified in only half of all respiratory infections. The eradication of the pathogen has to be the first aim if treatment is to be curative and the development of resistance prevented. Long-term prevention of antimicrobial resistance will require a more critical prospective evaluation of the prescription of antibiotics. This paper considers rational and irrational measures in the antimicrobial therapy of respiratory infections.