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Biomedical subjects

H G Fromme

Publications and source records attributed to H G Fromme.

At least 37 records · Page 2Linked to original sources
PubMed1978

Electron microscopic studies in cultivated plants. I. Green pods of Phaseolus vulgaris var. nanus L.

Scanning (SEM) and transmission (TEM) electron microscopic studies in the legumen of Phaseolus vulgaris var. nanus L. (kidney beans) were carried out. In this work emphasis was laid on the analysis of the morphological structure of the parenchyma tissue, being the chief component of the pod at edible maturity. The leaf character of the pod becomes especially evident by the occurence of stomata, trichomes, and typical cuticle structures on the outside of the pod (SEM). The cells of the mesophyll-like parenchyma tissue are distinguished by a great range of variation of their plastids (chloroplasts--chloroamyloplasts--amyloplasts) and some special cytological features such as a strongly developed rough ER, big nuclei, and numerous plasmodesmata (TEM).

Cell Nucleus↗
PubMed1978

Electron microscopic studies in cultivated plants. II. Fresh and stored roots of Daucus carota L.

Scanning (SEM) and transmission (TEM) electron microscopic studies in fresh and stored roots (4 months at an average temperature of +8 degrees C) of Daucus carota L. (carrots) were carried out. Chief stress was laid on the analysis of the histological and cytological structure of the secondary phloem parenchyma cell. SEM images show the three-dimensional histological arrangement of the cells. Moreover, the outlines of lipid droplets, mitochondria, starch grains, and carotin pigment crystals are visible within the parietal cytoplasmic layer. In TEM, besides the usual cell organelles (mitochondria, golgi-apparatus, ER, etc.) nuclei with several nuclear bodies can be recognised. The morphological structure of the chromoplasts shows a remarkable diversity. Within stored carrots a strong reduction of lipid droplets and starch grains within the chromoplasts takes place.

Carotenoids↗
PubMed1978

[Electron microscopic studies on pedicled grafts of alveolar mucosa and on newly formed periosteal epithelium].

20 patients who had undergone a vestibuloplasty using the technique of Edlan and Mejchar were examined by histo-morphological studies of the transplanted alveolar mucosa and the epithelialised periosteal zone up to one year post-operatively. The following conclusions were reached: --the original characteristics of the transplanted tissue remain unaltered. --numerous abnormalities in the epithelium and connective tissue are explained by insufficient oxygen diffusion and marked inflammatory reaction in the connective tissue. --there is no keratin formation although the number of layers of the stratum superficiale increases after the 16th post-operative week. On the basis of these results the question of whether there is a possible change-over from uncornified to a cornified epithelium is answered in the negative.

Adolescent↗
PubMed1978

Morphological and autoradiographical characterization of membrane-like layers surrounding cultured fibroblasts.

Two membrane-like layers of approximately 7 nM thickness were observed in ultrathin cross-sections of flat-embedded cultured fibroblasts. One "membrane", underlying the cell-monolayer, possibly established contacts between cells and substratum. The other "membrane" covered the whole cell culture. These "membranes" were at least partially synthesized by the cells themselves, as was shown by high resolution autoradiography. With regard to our biochemical findings, the autoradiographical results showed that components of these "membranes" consisted of sulfated proteoglycans and may be the morphological equivalent to the biochemically well-defined cell surface associated material, the so-called pericellular pool of glycosaminoglycans.

Animals↗
PubMed1975

Metabolism of sulfated glycosaminoglycans in cultivated bovine arterial cells. I. Characterization of different pools of sulfated glycosaminoglycans.

"Fibroblast-like" cells from the intimal layer of bovine aorta were grown in culture. The formation, composition, molecular weight and turnover rate of different pools of glycosaminoglycans were investigated in cultures incubated in the presence [35S]sulfate or [14C]glucosamine. The newly synthesized glycosaminoglycans are distributed into an extracellular pool (37 - 58%), a cell-membrane associated or pericellular pool (23 - 33%), and an intracellular pool (19 - 30%), each pool exhibiting a characteristic distribution pattern of chondroitin sulfate, dermatan sulfate, heparan sulfate and hyaluronate. The distribution pattern of the extracellular glycosaminoglycans resembles closely that found in bovine aorta. A small subfraction of the pericellular pool - tentatively named "undercellular" pool--has been characterized by its high heparan sulfate content. The intracellular and pericellular [35S]glycosaminoglycan pools reach a constant radioactivity after 8-12 h and 24 h, respectively, whereas the extracellular [35S]glycosaminoglycans are secreted into the medium at a linear rate over a period of at least 6 days. The intracellular glycosaminoglycans are mainly in the process of degradation, as indicated by their low molecular weight and by their half-life of 7 h, but intracellular dermatan sulfate is degraded more rapidly (half-life 4-5 h) than intracellular chondroitin sulfate and heparan sulfate (half-life 7-8 h). Glycosaminoglycans leave the pericellular pool with a half-life of 12-14 h by 2 different routes: about 60% disappear as macromolecules into the culture medium, and the remainder is pinocytosed and degraded to a large extent. Extracellular and at least a part of the pericellular glycosaminoglycans are proteoglycans. Even under dissociative conditions (4M guanidinium chloride) their hydrodynamic volume is sufficient for partial exclusion from Sepharose 4B gel. The existence of topographically distinct glycosaminoglycan pools with varying metabolic characteristics and differing accessibility for degradation requiresa reconsideration and a more reserved interpretation of results concerning the turnover rates of glycosaminoglycans as determined in arterial tissue.

Animals↗