Biocompatible magnetic polymer carriers for in vivo radionuclide delivery.

The magnetic guidance of antiplastic and antibacterial agents as well as x-ray and MRI contrast substances in vivo by means of magnetic particles has been attempted repeatedly during the last 2 decades with more or less success. When using microparticles, the circulation time in the blood, the biodistribution, and to a greater or lesser extent, the specific targeting are determined by the uniformity of size, chemical composition, surface modification, and the electric surface charge. The electrophoretic mobility is an important parameter for the prediction of the usefulness of the prepared particle, modified by chemical and biological molecules. For its success, radionuclide therapy depends on the critical relationship between the amount of radioactive isotopes in the target tissue and in critical normal tissue. Because the implementation of radioimmunotherapy for the treatment of cancer has proven to be considerably more difficult than initially anticipated, we propose the use of magnetic nanospheres for the well directed delivery of radionuclides to a tumor after the intravenous administration of the biodegradable colloidal suspension.

[Can disabled persons have "full social value"?]. / Können Behinderte "vollwertig" sein?

Starting out from some value theory-based considerations, the author subsequently questions the concept of being "fully adequate" ("vollwertig", literally: "full value") in light of the human condition, and in particular in its relation to persons with disabilities. In the context of biotic, human life as a fundamental value, a critical discussion ensues of the position held by P. Singer concerning person status of beings, with the degree of biotic perfection of man the focal point of discussion here. Extensive thought is given to the rank of human achievement within the social value system, and its meaning to persons with disabilities. Achievement is accepted as a value, given full awareness of its relativity. For persons with profound disablement, for very old and frail persons, an entitlement, without any counter consideration required, to recognition and valuation of their existence is posited, which includes the need to create overall conditions enabling humane dying in light of the concrete circumstances.

[The trend distribution quotient, a new tool for evaluating renal perfusion scintigraphy using 99mTc-DTPA following renal transplantation]. / Der Trendverteilungsquotient, ein neues Werkzeug zur Auswertung der Nierenperfusionsszintigraphie mit 99mTc-DTPA nach Nierentransplantation.

We developed a new quantitative concept in dynamic renal transplant imaging, the Trend Distribution Ratio, and tested its diagnostic usefulness in 137 examinations. This ratio is an expression of the distribution of blood flow velocity in different areas of the kidney. With regard to the differential diagnosis between acute tubular necrosis and the various forms of rejection we arrived at a sensitivity of 0.83 and a specificity of 0.54. A differentiation between the various histological types of rejection has not yet been possible.

A hypothalamic channel-system in the inferior lobes of a trigger-fish (Rhinecanthus aculeatus, Balistidae).

In the course of a general investigation of the optic system in some trigger-fishes, a hypothalamic, ventricular channel-system with pores, leading to the outside of the brain, has been discovered in the inferior lobes of Rhinecanthus aculeatus (Balistidae). A description of the morphological relations of the channel-system to the blood-vessel-supply and the cranium suggests that the organ-systems involved form a functional unit. The possibility of a hormone-producing system is discussed in the light of physiological and ecological aspects.

Chemical structure and pharmacokinetics of 99mTc-labelled aminomethane diphosphonic acid derivatives.

99mTc-labelled derivatives of aminomethane diphosphonic acid, general formula: R1R2N-CR3 [PO(OH)2]2, as well as hydroxyethane diphosphonic acid and hydroxypropane monophosphonic acid were investigated with regard to their suitability for skeleton scintigraphy. Bone accumulation was related to chemical structure. It was concluded from the experiments that compounds able to form enols are accumulated to a higher degree and that big substituents influence the affinity to bone negatively by steric hindrance.

[Biological modelling of potassium metabolism]. / Biologische Modellierung des Kaliumhaushaltes.

1. General principles of the modelling of compartments were described with the aim to use this methodology for the investigation of the potassium metabolism. 2. For the modelling of the potassium metabolism the necessary processes of investigation and calculations in the analysis of 42-potassium-kinetics were described in detail at an example. 3. By analogy references to the haemodynamics the general significance of the modelling of compartments was explained.

[Methods and quality of information from myocardial scintigrams in the diagnosis of myocardial infarct]. / Methodik und Informationsgehalt des Myokardszintigramms in der Infarktdiagnostik.

There is an increasing importance of scintigraphy for the assessment of microcirculation in the myocardium. In animal experiments advantages and disadvantages of negative and positive representation of ischemic myocardiac areas were tried, after experimental infarction in particular. The results by computer scintigraphy prove that positive representation reveals an information on site and extent of an infarction.