Cellular growth, injury and death

Kurzfassung

Vom Gesichtspunkt molekularer Mechanismen sind biologische Vorgänge außerordentlich komplex. In der vorliegenden Studie wird der Versuch unternommen, auf der Basis eines Modellsystems das Zusammenwirken funktioneller Grundeinheiten der Zelle zu einem System aufzuhellen. Die Flußgleichungen des Modellsystems werden aufgestellt und in die entsprechenden Differentialgleichungen transformiert. Für den Wachstumsvorgang wird unter verschiedenen Parameterbedingungen eine Analog-Computer-Analyse durchgeführt; ferner werden die Phänomene Zellschädigung und Tod analysiert. Experimentelle Studien am Computer gewähren wichtige Einblicke in die grundlegenden Wachstumsvorgänge und in die Wachstumsdesorganisation durch äußere Einwirkungen.

Summary

• 1. A functional model-system has been helpful in elucidating the problem of cellular growth kinetics. Computer studies with the model-system have made it possible for us to obtain some information in regard to interrelationships between various functional entities as well as on the effect of various parameters on the growth process.

• 2. These studies include the effects of the various entities on normal growth. The phenomenon of cellular viability and the recovery of viability has been elucidated, and it has been shown that the organization pattern plays a dominant role in a functional system.

• 3. While the simulation of the cellular system with the model has produced some highly interesting results, the complexity of the problem, raises many new issues. In order to make a model-system analysis more penetrating for gaining insight into biological processes, the model-system has to be expanded. It should especially contain more regulatory mechanisms.

• 4. In our experience, it was extremely difficult to obtain a solution on the computer for the differential equations representing the model-system. Sometimes it was thought to be impossible. Consequently, one has to introduce new features into the model-system gradually.

• 5. Since a functional system has been obtained, however, there is no apparent difficulty to supplementing within certain limits additional features involving regulatory mechanisms at various levels. This can be done with available computer facilities.

• 6. More expanded model-systems will also require new computer developments. Here again, there is no apparent limitation from the computer technology point of view. The problem is mainly economic.