PubMed Health⌕ Search

Biomedical subjects

R Schultheis

Publications and source records attributed to R Schultheis.

8 recordsLinked to original sources

[Catastrophy management in the large clinic. Bridges between fundamental research and rescue practice].

In consequence of a fire that had broken out in the large general hospital centre of the University of Aachen, a working team was organised to systematise the experiences gained and to work out an internal scheme for handling catastrophic events. It was the declared aim of the working group to study and come to grips with innovative concepts of self-organisation in social systems and with cognitive trouble-shooting research to assess the relevance of actions based on these factors, the purpose being to complement and widen the range of conventional concepts of managing catastrophic events and the relevant security measures. This study discovered general agreement between the reflected experiences as seen from the viewpoint of the working team on the one hand, and the theoretical considerations of cognitive trouble-shooting research and the concepts of self-organisation in complex systems on the other. The innovative potential of knowledge for the internal management of catastrophic events derived in this manner from actions can hardly be over-estimated.

Disaster Planning↗

Preparative isolation of middle molecular weight fractions from the hemofiltrate of patients with chronic uremia.

Fractions in the molecular weight range of the so-called middle molecules (500--3000 daltons) were isolated on a preparative scale from hemofiltrate of patients. Hemofiltration was performed with an RP-6 dialyzer using a predilution technique. The hemofiltrate was concentrated and desalinated by reverse osmosis with membranes with a normal cut-off of 500 daltons. The retentate was freeze-dried, redissolved in volatile buffer and fractionated on Sephadex G-15 macrocolumns. The middle molecule molecular weight range in the elution profiles (detected at 206 and 280 nm simultaneously) was marked with peptides. Isolated fractions in the middle molecule molecular weight range showed strong inhibitory activity upon 3H-thymidine incorporation into rat bone-marrow cells in vitro. The described combination of hemofiltration, reverse osmosis and gel chromatography is suggested as a useful approach to the isolation of these ninhydrin-positive substances which, according to their proved heterogeneity, are to be subfractionated by further procedures.

Chromatography, Gel↗

Myocardial oxygen consumption and regulation of coronary blood flow during stepped relief of the left ventricle.

In 25 calves an atrio-ventriculo-aortic bypass was performed and the metabolism and the regulation of coronary blood flow during stepped assistance of the left ventricle was studied. With mean aortic blood pressure kept constant stepped decrease in left ventricular pressure from 120 to 0 mmHg diminished myocardial oxygen consumption from 7.7 to 1.9 ml O2/min X 100 g. Increasing right ventricular pressure by banding the pulmonary artery with left ventricular pressure and mean aortic pressure kept constant the oxygen uptake of the left ventricle increased about 20.7 +/- 32.% when measured by Fick's principle but remained unchanged when calculated from hemodynamic parameters of the left ventricle (-1.5 +/- 3.5%). At constant coronary perfusion pressure coronary blood flow decreased when left ventricular pressure was reduced from 120 to 100 mmHg. Further decrease in left ventricular pressure to 0 mmHg showed no effect on coronary blood flow. Increasing heart rate from 152 +/- 9 to 208 +/- 8 b.p.m. enhanced myocardial oxygen uptake of the assisted heart about 59.0 +/- 11.4% while resistance to flow decreased about 40.4 +/- 2.8%. These results show that the metabolic regulation of coronary blood flow is still acting even in the assisted left heart.

Animals↗