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T Ammitzbøll

Publications and source records attributed to T Ammitzbøll.

30 records · Page 2Linked to original sources
PubMed1984

Changes in the content and composition of collagen in the glaucomatous eye--basis for a new hypothesis for the genesis of chronic open angle glaucoma--a preliminary report.

The pressure theory is still predominant in explaining the pathophysiology of the chronic open angle glaucoma. An insufficient drainage system resulting in an increased intraocular pressure is the basis for this theory. The pressure will exert an effect upon the optic disc which either directly on the nerve fibres or indirectly via the vascular system will result in a characteristic optic atrophy. The collagen fibres, both in the trabecular meshwork of the anterior chamber and in the lamina cribrosa of the optic disc, form a mesh through which the aqueous humour and the nerve fibres, respectively, pass through the wall of the eye. A hypothesis explaining the pathophysiology of this disease, and based on the assumption that there is a primary change in the collagen molecules, resulting in a weaker structure than normal both in the trabeculae and in the laminae, is forwarded. The structures analysed for the content of hydroxyproline, hydroxylysine and proline were the trabecular meshwork, the sclera and the lamina cribrosa. Three categories of autopsy eyes were studied, i.e. normal eyes, glaucomatous eyes, and eyes under a suspicion of glaucoma. In the normal eyes, the collagen composition in the trabecular meshwork was different from that in the sclera and the lamina cribrosa. There is also a difference in the composition between the sclera and the lamina cribrosa. In glaucoma, the content and/or the composition of the collagen molecules in the lamina were significantly changed. In the eyes under suspicion of glaucoma the same changes as in the glaucomatous eyes could be demonstrated. However, 5 of the 7 eyes in this category had no demonstrable nerve atrophy. The findings suggest that the change in collagen pattern is primary. This study has not demonstrated which types of collagen are present or the physical properties of this collagen. Further tests to demonstrate the different types of collagen and their rigidity are planned.

Aged↗
PubMed1984

Collagen in the esophageal mucosa of patients with progressive systemic sclerosis (PSS).

Eighteen consecutive patients with an established diagnosis of Progressive Systemic Sclerosis (PSS) underwent different investigative procedures to determine possible esophageal involvement. Esophageal sclerosis was demonstrated by X-ray and manometry in 13 patients. In all patients endoscopic biopsies of esophageal mucosa were obtained. In all biopsies the concentrations of hydroxyproline, hydroxylysine and proline were determined. Patients suffering from PSS involving the esophagus were found to have a significantly higher concentration of collagen specific amino acids (hydroxyproline and hydroxylysine) in the esophageal mucosa (endoscopic obtainable biopsies) than patients with PSS not affecting the esophagus.

Adult↗
PubMed1984

Collagen metabolites in urine in localized scleroderma (morphoea).

Hydroxyproline (Hyp), hydroxylysine (Hyl), and proline (Pro) were assayed in the urine from 28 patients with localized scleroderma (13 with localized morphoea plaques, 13 with generalized morphoea, and two with scleroderma en coup de sabre), as well as 17 control persons. The levels of Hyp, Hyl and Pro were elevated in patients with localized morphoea plaques as compared to the controls indicating major changes of the collagen metabolism in this type of localized scleroderma.

Adolescent↗
PubMed1984

Collagen specific amino acids in skin in localized scleroderma.

Hydroxyproline, hydroxylysine and proline were determined on skin from 18 patients with localized scleroderma (10 with localized morphoea plaque and 8 with generalized morphoea). Three skin biopsies (4mm punch) were obtained from each patient: One from the center of a sclerotic plaque, one from the perilesional area, and one (control) from unaffected skin of the same region. Clinically, the sclerosis was more pronounced (p less than 0.01) in localized morphoea plaque as compared to generalized morphoea. Patients with localized morphoea plaque had an increased concentration of hydroxylysine (p less than 0.01) and an increased ratio of hydroxylysine to hydroxyproline (p less than 0.01) in the plaques. Hydroxylysine concentration was not changed in patients with generalized morphoea. In the entire material, increased hydroxylysine concentration were related to shorter age of the plaques (p less than 0.05) and to advanced degree of sclerosis (p less than 0.05). The hydroxylysine and hydroxyproline content per mm2 skin surface, and the weight of the dried defatted biopsy cores were increased in sclerotic plaques (p less than 0.01) in localized as well as generalized morphoea. There were no changes in the hydroxyproline and proline concentrations in any of the groups. Specimens from perilesional area showed intermediate changes. The results were compared with selected cases of lichen sclerosis et atrophicus and atrophic skin diseases. The increase in hydroxylysine concentration and ratio to hydroxyproline indicate that patients with localized morphoea plaque contain an increased proportion of newly synthesized collagen in the fibrotic plaque.

Adolescent↗
PubMed1982

Ultrastructure of skin and hair of an Egyptian mummy. Transmission and scanning electron microscopic observations.

The skin of a female Egyptian mummy, embalmed 100-300 A.D., was studied by transmission and scanning electron microscopy. After rehydration with cacodylate buffer containing sucrose, the ordinary technique for transmission electron microscopy was performed on skin of the right shoulder. In epidermal cells, mitochondria and their cristae were identified. Between epidermal cells, desmosomes, half the normal size, were found. In the dermis, collagen bundles and elastic fibres were observed. The collagen fibres had a diameter of 67-91 nm, and the band pattern showed 10-12 sub-bands per one period of 55-61 nm length. The elastic fibres had less amorphous substance than normal and a fibrillar beaded pattern. The dermal components of the skin were well preserved in spite of the mummification. Throughout the dermis and the subcutaneous fatty tissue, a number of bacterial spores were found showing a characteristic appearance. Scanning electron microscopy of hairs showed a layer of the preserving material surrounding hairs, and under it a normal cuticle was seen.

Egypt↗
PubMed1982

The ultrastructure of bacterial spores in skin of an Egyptian mummy.

The ultrastructure of bacterial spores found in the skin of an Egyptian mummy was studied. The mummy was embalmed during year 100 to 300 of our era. The bacterial spores showed a characteristic appearance with a core, cortex, coat and exosporium. Their survival and species could not be established.

Humans↗
PubMed1982

Local panatrophy with linear distribution: a clinical, ultrastructural and biochemical study.

A young female with local panatrophy of the right-side extremities affecting all mesodermal layers--dermis, subcutaneous tissue, muscles, and bone--is described. The atrophies were strictly linear. Ultrastructurally, collagen fibrils of the reticular dermis from the atrophic area consisted of two types, a large population of fibrils with decreased diameter and round cut-surface, and a small population with increased diameter and a "flower-like" cut-surface. Collagen analysis revealed a reduced hydroxyproline concentration and content per mm2 skin in atrophic area as compared with the perilesional and regional control. Urinary excretion of hydroxyproline was normal. Glycosaminoglycan analysis showed a less reduced content of hexosamine and uronic acid in the atrophic area per mm2 skin, but no differences in the concentrations. Consistently, the gel/fibre ratio (uronic acid/hydroxyproline) was found slightly elevated in atrophic skin. The proportions of the individual glycosaminoglycans heparin, dermatan sulphate, hyaluronic acid and chondroitin sulphates were not affected. It is concluded that reduced collagen and ultrastructural changes of collagen fibrils are significant features in local panatrophy. The significance of local foetal factors affecting the somatic mesoderm is discussed.

Adolescent↗
PubMed1982

Acantholysis induced by proteolytic enzymes. II. Enzyme fractions produced by Trichophyton mentagrophytes.

Trichophyton mentagrophytes produces three enzyme fractions of molecular weight 65,000, 92,000 and 18,000, respectively. Normal human skin was cultivated and the specimens were subjected to electron microscopy. Enzyme fraction I showed the capacity to induce epidermal acantholysis and dermo-epidermal separation, while the other two fractions showed no proteolytic nor keratinolytic action in cultivated skin.

Acantholysis↗
PubMed1981

Triethyllead treatment of cultured brain cells. Effect on accumulation of radioactive precursors in galactolipids.

Cultured cells from chick embryo brains were studied for their sensitivity to triethyllead. Triethyllead chloride (3.16 microM) was added to the nutrient medium and incubated for 48 hr with the cells. Morphological changes in light microscope and radioactive labeling of galactolipids were assayed. Triethyllead treatment reduced the number of neuronal cells with processes. Morphological changes were not observed in glial cells. The [35S]sulfate labeling of sulfatides was reduced to 50%. The [3H]serine labeling of cerebrosides with alpha-hydroxy fatty acids was not influenced, while the [3H]serine labeling of cerebrosides with nonhydroxy fatty acids was inhibited 40% in one- and two- but not in three-week-old cultures. The results indicate that the nerve cell response to triethyllead in cultures is selective, since the neurons are more sensitive than the glia cells and the labeling of sulfatides is more sensitive than that of cerebrosides.

Animals↗
PubMed1978

Toxicology of triethyllead, methylmercury and cadmium, determined in chick embryo brain cell cultures.

The toxicology of water soluble chemical compounds may be investigated in tissue culture systems. The toxicology of triethyllead chloride, methylmercury chloride and cadmium acetate was studied in chick embryo brain cell cutlures. Tetraethyllead is added to petrol as an anti-knock agent. When tetraethyllead is absorbed by the organism, it is converted to triethyllead which cause the symptoms of tetraethyllead poisoning. Chick embryo brain cell cultures derived from cerebrum of 11-day-old chick embryos developed both neurons and glial cells. The neurons formed nerve processes and synapsis in the cultures. The effect of triethyllead chloride was investigated by addition of triethyllead chloride to the nutrient medium. The median tissue culture lethal dose, TCLD50 = 1.9 mg/l, was determined as the concentration of triethyllead chloride at which the confluent layer of glial cells was destroyed in 50% of the cultures. The neurons lost their processes at even lower concentration, TCED50 = 0.57 mg/l. Electron microscopy revealed cells with swollen Golgi apparatus and dilated endoplasmic reticulum in chick embryo brain cell cultures which were treated with triethyllead chloride, 1.0 mg/l. Studies with radioactive labelled precursors revealed that triethyllead chloride inhibited the synthesis of DNA, sulfatides and cerebrosides without hydroxyfatty acids.

Animals↗