Biomedical subjects

R M Ludatscher

Publications and source records attributed to R M Ludatscher.

31 records · Page 2Linked to original sources

PubMed1981

Patterns of regeneration in vessels of human diseased muscle and skin. An ultrastructural study.

Regenerating vessels from 36 muscle biopsies and 12 skin biopsies pertaining to patients with the clinical and histological diagnosis of dermatomyositis-polymyositis and other inflammatory myopathies were described ultrastructurally. The following characteristics of vascular regeneration were encountered: a) alternation of thin and thick endothelial cells, b) superimposed segments of endothelial cytoplasm with formation of twisted intercellular junctions, c) long and complex intraluminal endothelial projections, d) discontinuous and porous perivascular basement lamina or multilaminated basement lamina. Some vessels featured only two or three of the mentioned characteristics. Endothelial fenestrations were occasionally encountered in the skin capillaries and were an exception in the muscle capillaries. In the skin there were aspects suggesting that intercalation of perivascular cells in the regenerating endothelial wall may occur. Most capillaries were in the final stage of regeneration.

Adolescent↗

PubMed1981

Progressing alterations in transient ischemia of skeletal muscles: an ultrastructural study.

Ultrastructural muscle changes resulting from temporary anoxia and their evolution were studied in dogs. Ischaemia of the hind limb was produced by subcutaneous ligation of all muscles of the thigh and clamping of the femoral artery. Revascularization was obtained by declamping and removal of the muscle ligature. The period of ischaemia ranged from 4 1/2 to 7 h, the latter being the upper limit allowing functional recovery after revascularization. 6-7 h of ischaemia revealed focal degenerative changes of varied intensity. These consisted of enlarged mitochondria with ruptured cristae, small pads of glycogen granules and accumulation of lipid vacuoles. The tubules of sarcoplasmic reticulum contained dense, fine-granular material. Focal myofibrillar destruction and disruption of the Z line were encountered in half of the cases. The myofibrillar damage was more severe 9 days after revascularization of the muscles. The functional recovery of the ischaemic limbs in the present study may be due to the focal nature of these changes.

Animals↗

PubMed1981

Electron microscopic studies in lipid storage disease.

Biopsy and autopsy specimens from patients with Gaucher's disease and Niemann-Pick disease were studied ultrastructurally. The morphological features were compared with those obtained from paraffin-embedded tissues after reprocessing the tissue for electron microscopy. With routine glutaraldehyde-osmium fixation, both surgical and autopsy specimens from Gaucher's disease showed cytoplasmic bodies containing elongated tubular structures with a translucent appearance. Tissue processed from paraffin-embedded blocks showed moderate preservation of the cytoplasmic glucocerebroside-containing bodies in Gaucher's disease. Routine fixation for electron microscopy of surgical of surgical and autopsy specimens from Niemann-Pick disease showed characteristic cytoplasmic vacuolated formations which were frequently multilaminated. These sphingomyelin-containing vacuoles were poorly preserved in tissue reprocessed from paraffin blocks.

Adult↗

PubMed1979

Ultrastructural observations on the capillaries of human thyroid tumours.

Ultrastructure of the capillaries of malignant and benign thyroid tumours has been examined. The material consisted of biopsies from six cases of thyroid papillary carcinoma, one case of follicular (foetal type) adenoma and six cases of nodular adenomatous goitre. In the group of nodular adenomatous goitre and in the follicular adenoma, the capillary wall was made up of fenestrated endothelium similar to that of capillaries of normal human thyroid. The fenestrae occupied a large area of the endothelial wall. Micro- and macropinocytotic vesicles were frequent in the endothelial cytoplasm. In the thyroid carcinomas the papillary structures always contained numerous capillaries with fenestrated endothelium. The microfollicular area and the solid tumoral areas of the papillary carcinoma showed occasional capillaries with fenestrated endothelium, but many capillaries were lined with continuous endothelium. The capillaries in all the specimens were surrounded externally by a continuous basement membrane which was frequently bilaminate or multilaminate. This study indicates that capillaries with fenestrated endothelium are characteristic of thyroid tumours which arise from follicular cells.

Adenoma↗

PubMed1978

Ultrastructure of human dermal blood vessels with special reference to the endothelial filaments.

The ultrastructure of endothelial cytoplasmic filaments of small blood vessels from the human dermis has been described. The material consisted of biopsies from normal abdominal and thoracic skin and also from the skin of patients with urticaria pigmentosa. Most vessels were surrounded by multiple layers of basal lamina and corresponded to the small venules of the subpapillary dermis. The wall of many vessels was composed by endothelial cells with clear cytoplasm which was rich in filaments and by endothelial cells with a dense cytoplasm which was poor in filaments. Some vessels had walls composed of clear endothelial cells only. The filaments varied in diameter between 80-120 A. Curling, recoiling and whorling of cytoplasmic filaments were obvious in endothelial cells of contracted vessels. Bulging of endothelial nuclei and nuclear indentations were seen in the skin lesion of urticaria pigmentosa. The possibility that the clear endothelial cells which are rich in filaments may be more actively involved in contraction than the dense cells, is discussed.

Adult↗

PubMed1978

Myotonia dystrophica with heart involvement: an electron microscopic study of skeletal, cardiac, and smooth muscle.

The electron microscopic features of the striated skeletal muscle, the striated cardiac muscle, and the smooth muscle from a woman who had been suffering for many years from myotonia dystrophica with cardiac involvement are described. The skeletal muscle was studied at two different stages of the disease. In the first material the main changes consisted of centrally situated nuclei, disorganisation of the sarcomeres, and focal disruption of the Z-line. The satellite cells were well represented. Three years later atrophy and degenerative, necrotic changes of the skeletal muscle were evident. The satellite cells were absent. Few changes were seen in the striated cardiac muscle. These consisted of slight interstitial fibrosis and large accumulations of mitochondria with intramitochondrial dense granules. The smooth muscle cells of the oesophagus showed disorientated filaments and mild degenerative changes. It is concluded that the skeletal muscle was more severely affected than the other types of muscle.

Aorta↗

PubMed1977

Comparative ultrastructural study of mast cells in mastocytoma and mastocytosis.

The ultrastructural aspects of mast cells from skin lesions in 2 patients with mastocytoma were compared to those from lesions in 4 patients with mastocytosis, 3 with cutaneous and 1 with systemic involvement. In mastocytoma, the mast cells accumulated in a large mass. They revealed short cytoplasmic villi and were similar, morphologically, to mast cells of normal skin and gingiva. In the diffuse types of the disease, cutaneous and systemic, the cells were arranged in small groups. In addition to normal mast cells, there were also irregular or bizarre-shaped cells presenting long and twisted cytoplasmic protrusions. In the case with the systemic involvement and in 2 of 3 cases with apparently cutaneous diffuse lesions, the villi of adjacent cells interlaced and showed a tendency to form mast cell aggregates. The pathognomonic value of the above observation seems worthy of further investigations.

Cell Membrane↗

PubMed1973