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Biomedical subjects

U Heinzmann

Publications and source records attributed to U Heinzmann.

At least 55 records · Page 3Linked to original sources
PubMed1990

Surface structures and epicuticular wax composition of spruce needles after long-term treatment with ozone and acid mist.

Epicuticular wax structures and epicuticular wax composition were studied in needles of Picea abies (L.) Karst. plants after a long-term fumigation experiment. SEM observations showed aggregated as well as undamaged waxes without any relation to treatments. The chemical wax analysis revealed clone specific differences, but only one compound, the nonacosan-10-ol (C(29)-ol), was found enriched in ozone/acid mist treatments.

Journal Article↗
PubMed1989

The effect of fetal irradiation on the growth of postnatally xenotransplanted tumour cells.

Exposure of the mouse fetus (NMRI-strain) to 1.0 Gy X-irradiation has a marked effect on postnatally xenotransplanted glioma cells. In comparison to non-irradiated animals, irradiation on gestation day 14 resulted in: (a) a significantly higher rate of animals which failed to develop visible tumours growing from the inoculum; (b) a significant inhibition of the growth rate of solid gliomas; (c) a pronounced granulocytic and mast cell infiltration, and tissue necrosis, in the invading gliomas. The results suggest that irradiation in prenatal life exerts an amplifying effect on the antitumour response in postnatal life.

Animals↗
PubMed1988

Scanning electron microscopic studies of the nasal blood vessels.

Current histological and transmission electron microscopic techniques are insufficient for studying all different aspects of vascular morphology. As a result, we have used scanning electron microscopy (SEM) to examine nasal blood vessels. In our present studies the nasal septa of 15 rabbits were fixed by vascular perfusion, dried by the critical point method and coated with gold for SEM studies. Lower magnifications of specimens using this method show the tissue arrangement in the nasal septum. In higher magnifications the different vessels can be distinguished by their morphological features. The course of the vascular structures can be observed as well as the junctions between the different vessels. Our results indicate that different morphological techniques must be combined to understand the endonasal vasculature.

Animals↗
PubMed1988

[The variability of the surface morphology of olfactory sensory receptors].

The olfactory epithelium of the adult hamster (mesocricetus auratus) was examined by light- and scanning electron microscopy. Tissues were perfusion-fixed in buffered glutaraldehyde solution. Of particular interest were the regionally varying, thickly structured olfactory boarder and the polymorphic olfactory receptors. The forms varied from simple, smooth olfactory vesicles to highly differentiated receptors with up to 20 cilia of varying length per vesicle. The cilia were tapered at such a rate that the distal segments had an average diameter 1/2 to 1/3 of the proximal segment. The distal segments were arranged in a parallel fashion occasionally over more than 100 microns in length between the surface of the epithelium and the loose meshlike plexus of the olfactory border. A second receptor type was also frequently observed in which the surface area was increased through microvilli. These variations in the structure of the receptors are discussed with regard to new immunohistochemical results. Further experiments should determine the relationship of local morphological differences.

Animals↗
PubMed1988

[The angioarchitecture of the septal mucosa. Experimental studies of the rabbit].

Histological and transmission-electron microscopical studies alone cannot answer all questions regarding the microcirculation of the nasal mucosa. In the present study additional morphological techniques were used to demonstrate the course of the different parts of this peculiar vascular network. Using the "injection technique", the course of every single vessel of the nasal septum could be shown, but the character or size of these vascular structures was not easy to identify. Scanning electron microscopic investigations were able to verify vascular junctions of all sizes as well as intraluminal aspects of different vessels and the relations between all parts of this endonasal circulatory system. Lower magnifications also showed the tissue arrangement in the nasal septum. In higher magnifications vessels of arterial or venous character could be identified by distinct morphological features. Additional studies were carried out using vascular corrosion casts. On studying these structures, the entire course of the different parts of the endonasal vascular system could be observed. In addition, the arrangement of the different capillary networks of the nasal system, mentioned by several earlier investigators, could be demonstrated without doubt. This technique also allowed to distinguish between arteries and veins by the appearance of their endothelial cell nuclei. Summing up our findings it can be pointed out that all techniques used in this study are useful to understand the complicated angioarchitecture of the nasal mucosa. This evaluation may also be regarded as an extension of our earlier histological and ultrastructural investigations in this field.

Animals↗
PubMed1987

[Vascular reaction in tumors in the area of the head and neck].

The vascular system possesses a variety of possibilities to respond to noxious events. Particularly the "morphological reaction" can first be observed in ultrastructural changes of the endothelial cell. In the present study we report on endothelial cell reactions in various carcinomas of the head and neck (carcinoma of the auricle, carcinoma of the maxilla). It is shown that the endothelial cell develops cytoplasmatic processes projecting into the vascular lumen. Occasionally cell edemas can be observed. The use of the scanning electron microscope allows to visualize three-dimensional aspects of the excised specimen. Tumor cells, endothelial cells and erythrocytes are obviously mixed, so that a regular vascular lumen can be found within the tumor tissue only occasionally. The results are compared and discussed, basing on available references.

Carcinoma, Squamous Cell↗