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R Kästner

Publications and source records attributed to R Kästner.

32 records · Page 2Linked to original sources
PubMed1984

[Comparative study of the efficacy of the DBVCy protocol (daunoblastin, bleomycin, vincristine, cytostasan) and the ABVD protocol in advanced Hodgkin's lymphoma. A prospective inter-clinic study within the framework of the Hauptforschungsrichtung Geschwulsterkrankungen].

In MOPP-resistant patients with Hodgkin-lymphoma stage III B and IV the well known ABVD-protocol was compared with the DBVCy-protocol (daunorubicin, bleomycin, vincristine, cytostasan) in a randomized prospective trial. 73 patients were evaluable, 35 received ABVD, 38 DBVCy. 4 out of 35 (11%) in the ABVD-group and 9 out of 38(24%) in the DBVCy-group reached complete remission. The median duration of the remission for DBVCy was 4,5 months, for ABVD 3,4 months (no significance). Median survivals (61 months in DBVCy and 37 months in ABVD) did not show significant differences; but the DBVCy-scheme seems to be better tolerabel. With the given evaluation can not be proved a difference between the two groups, but it is not likely, that one of the regimen is very much better or very much worse as the other.

Adult↗
PubMed1984

Astroglial-axonal interrelationship during regeneration of the optic nerve in goldfish. A freeze-fracture study.

The cytoplasmic membranes of astrocytes in the regenerating optic nerve of the goldfish were investigated by means of freeze-fracture technique. In contrast to avian and mammalian astrocytes the astrocytes in the fish white matter do not reveal the characteristic orthogonal particle assemblies. Whereas astrocytes hitherto were believed to be interconnected mainly by gap junctions, astrocytes in the optic nerve of the goldfish are additionally interconnected by prominent desmosomes and large tight junctions. The tight junctional strands are frequently intercalated by gap junctions. Astroglial membrane domains, which are directly juxtaposed to untreated myelinated optic fibers, are longitudinally deformed. The distance of these longitudinal grooves corresponds to the caliber of fibers associated with them. The intramembranous particles in these membranous domains are distributed randomly. During optic nerve regeneration, membranes of astrocytes associated with regenerating, still unmyelinated fibers are either longitudinally deformed or smooth. If deformed according to the axonal course the membrane shows a non-random distribution of intramembranous particles; if smooth, the membrane shows a random distribution of its particles. The non-random particle distribution in the astrocytic P-face is characterized by an impoverishment of particles along the concave groove and an enrichment of particles along the convexe bulge which corresponds to the wedge between two associated axons. This phenomenon is restricted to the regeneration period and disappears some weeks after recovery of vision. Then the astrocytic membranes which are associated to regenerated fibers are undulated nevertheless revealing a random particle distribution. It is suggested, that these findings reflect a glial-neuronal interrelationship characterized by the neuron as inductor and the glial cell as responder to axonal signals. The astroglial response to axonal signals would include the formation of attractive glial channels. The working hypothesis is proposed that the presence of orthogonal particle assemblies could contribute to a disturbed astroglial response in the mammalian central nervous system.

Animals↗
PubMed1983

Lack of orthogonal particle assemblies and presence of tight junctions in astrocytes of the goldfish (Carassius auratus). A freeze-fracture study.

The cytoplasmic membranes of astrocytes in the optic nerve of the goldfish were investigated by means of freeze-fracture techniques. Astrocytes of normal and regenerating optic nerves did not differ in the fine structure of plasma membranes. Emphasis is placed on the following results: Astrocytic membranes of fish do not reveal the orthogonal particle assemblies that are believed to be generally characteristic for astrocytes in the white matter. Astrocytes reveal extensive membrane areas occupied by tight junctions, which to date have not been described as characteristic astrocytic structures. These junctions are astro-astrocytic and are frequently intercalated by gap junctions. Desmosomes are another characteristic type of astro-astrocytic junction. By means of freeze-fracture replicas it can be demonstrated that they occur in more or less close association with tight and gap junctions. Caveolae are also seen in the astrocytic membranes of fish: their density and distribution show distinct variations. Caveolae occur at the interface between astrocytes and the interstitial space, between astrocytes and myelin sheaths, and in astrocytic processes. It is suggested that the differences between the astrocytic membranes of fish and mammals reflect different physiological functions. They are discussed in relation to the problem of neuronal-glial interrelationships and the behavior of astrocytes during fiber regeneration in the CNS.

Animals↗
PubMedDate not supplied

[Projective identification and denial of pregnancy--considerations of the reasons and background of unrecognized pregnancy also undiagnosed by a physician].

BACKGROUND: In denial of pregnancy, the pregnant woman does not consciously perceive the pregnancy and, in extreme cases, awareness occurs only during delivery. The attending physicians also often fail to recognize the pregnancy, even though the somatic complaints leading to consultation with a physician are typically pregnancy associated. This "iatrogenic participation" was described in the earliest historical publications. Different theories are presented in this paper to elaborate this phenomenon. Elementary deficiencies in perception or incompetence do not explain most cases. PATIENTS AND METHODS: Twenty five women with denial of pregnancy, interviews PSYCHODYNAMIC EXPLANATIONS: Based on the deep-rooted subjective attitude of not being pregnant, the pregnant woman is able to include family, friends, and associates into the denial of pregnancy mindset. In a similar way, she is able to influence her doctor. The woman's autosuggestive wishful notions of not being pregnant receive suggestive confirmation by the physician's misdiagnosis and lead to a continuing denial of pregnancy. PROJECTIVE IDENTIFICATION: In 1946, M. Klein introduced this term to describe a certain defense mechanism relating to fantasies and accompanying object relationships. The self initially successfully disposes of unwanted aspects, splits them off, and transfers them to another person, to finally reclaim them in a modified form. Certain elements of this psychoanalytical concept can characterize the interaction between physician and pregnant woman, which, in the case of denied pregnancies, does not lead to a diagnosis of pregnancy. Through projection, the pregnant woman is capable of manipulating the physician so that he perceives her, according to her wishes, as not being pregnant and misdiagnoses her correspondingly as "service in return". Opportunities for more mature handling of the denied content in terms of psychological development through accurate diagnosis of the pregnancy are indicated.

Adolescent↗
PubMedDate not supplied

[The oculomotor system--simulation of physiologic and pathologic horizontal saccadic eye movements].

Horizontal saccadic eye movements were analyzed by way of the input- and output-functions of the oculomotor system. On the basis of the parameters of the model, it was possible to simulate both physiological and pathological saccades. In this paper we present the results of simulation experiments that were performed to study the influence of various ocular motor disorders. The parameters of the model proved a useful diagnostic aid.

Adult↗
PubMedDate not supplied

Functional regeneration of the visual system in teleosts. Comparative investigations after optic nerve crush and damage of the retina.

Goldfish and carp are shown to be capable of functional reconstitution of the visual system, although their neural retina except of the marginal growth zone at the ora serrata was completely destroyed by injection of the Na-K-ATPase inhibitor ouabain. This was demonstrated by the observation of the recovery of the optokinetic nystagmus after damage of the retina. Recovery of vision coincides well with the morphological reconstitution of the visual system. The regenerated axons within the optic nerve are still unmyelinated at the moment of visual recovery, whereas some fibers within the stratum opticum pars profunda of the corresponding optic tectum are already myelinated. The recovery of vision after regeneration of the retina was compared with the recovery of vision after crush of the optic nerve. The range of time needed for visual recovery was smaller and better reproducible after crush than after damage of the retina.

Animals↗