Biomedical subjects
Publications and source records attributed to G Asboe-Hansen.
Differentiation of the pemphigus group of diseases from other bullous dermatoses can be established by spreading of blisters by gentle finger pressure. In combination with histopathology, the same test is diagnostic for every single pemphigus disease.
Increased serum values of aminoterminal type III procollagen peptide and hyaluronan (hyaluronate) and enhanced urinary content of hydroxyproline and hydroxylsine containing polypeptides were demonstrated in patients with progressive systemic sclerosis (PSS). The serum propeptide level and the relative urinary excretion of hydroxyproline as polypeptides were related to the extent of cutaneous involvement. Elevated serum propeptide and hyaluronan values were seen in patients who progressed within the following 6 months. Patients with CREST syndrome had normal propeptide values. Reduced renal propeptide clearance is a likely cause of high serum levels of propeptide degradation products demonstrated in PSS. Serum propeptide seems to be a useful novel marker for disease activity and progression in PSS because of its linkage to the actual connective tissue metabolism.
After a review of some pathogenetic and pathologic aspects of scleroderma, the experimental effects of a group of agents that can inhibit the formation of connective tissue, especially the biosynthesis of collagen, are mentioned. These substances were transferred to clinical therapy of scleroderma. Regular determinations of disease activity and guidance of therapy with quantitative and semiquantitative physical and biochemical technics are of utmost importance because treatment without guidance allows for no disclosure of therapeutic failure or recurrence of the disease in due time for readjustment of the treatment.
The bioavailability of D-penicillamine was measured in 24 patients with generalized scleroderma (Progressive Systemic Sclerosis, PSS). Esophageal changes characteristic of generalized scleroderma were present in 15 of the patients, and 3 of those patients had duodenal involvements as well. The plasma concentrations of D-penicillamine were measured at 0 h, 1 h, 2 h, and 4 h after an oral dose of 300 mg D-penicillamine. Patients with duodenal and/or esophageal changes specific for scleroderma had significantly lower bioavailability of D-penicillamine than scleroderma patients without gastrointestinal manifestations. The decreased plasma D-penicillamine in scleroderma patients with involvement of the gastrointestinal tract may be due to an increased degradation of D-penicillamine in the gastrointestinal tract and/or an impaired absorption of the drug. Since the plasma level of D-penicillamine is so sensitive to pathological changes of the gastrointestinal tract, it may be advisable to adjust the dose of D-penicillamine on the basis of measurements of the plasma concentration of D-penicillamine.
D-penicillamine pharmacokinetics were studied in a patient with gastrointestinal progressive systemic sclerosis possibly complicated by malabsorption. D-penicillamine bioavailability was examined after oral, duodenal, intravenous and rectal administration. No D-penicillamine was detectable in plasma after administration to the gastrointestinal tract. The pharmacokinetics after intravenous administration agreed closely with the corresponding situation in healthy volunteers.
Filamentous aggregates of collagen are distinct structures in the pathological dermis. These aggregates are distinguishable from fibrous long-spacing collagen (in vitro and at biopsy) and the Luse body. The aggregates are produced from dermal collagen fibrils by clostridial collagenase and culture-medium extract, which supposedly contains cellular collagenase at a neutral pH, as well as by organ cultures. In vitro experiments showed that carrageenan granuloma contains fibrous long-spacing collagen and segment long-spacing collagen. The granuloma also contains the aggregates. The aggregates were found in skin biopsies from syphilitic chancres, acrosclerotic scleroderma, morphea, mycosis fungoides, myeloid leukemia, mastocytosis and malignant melanoma. These findings indicate that the aggregates are products of the in situ degradation of collagen fibrils by some collagenolytic factor. This factor may originate in fibroblast-like cells, reticulum cells, leukemia cells, mast cells and melanoma cells.
Secretion of type IV collagen by keratinocytes was studied by anti-type IV collagen immunoglobulin in pure keratinocyte culture of the human adult. The cultivated keratinocytes secreted type IV collagen into the space between the cell growth and the underlying fixed film of human skin collagen type I. The secreted collagen was accumulated on the cell surface to form junction structures.
Seven patients with prurigo nodularis and one with aphthous stomatitis were given 40-115 g of thalidomide for 1 to 6 years. They all developed a predominantly sensory peripheral neuropathy mainly involving the lower limbs. Five patients had an unpleasant tight feeling around the feet. Nerve conduction studies showed small sensory action potentials from the lower limbs with normal or only mild slowing of sensory conduction velocity indicating an axonal neuropathy. The dermatological disorder improved dramatically in all, but treatment had to be discontinued because of the severe side-effects. Thalidomide, if used, should be given only over a short period because of its neurotoxic effect.
Hydralazine and dihydralazine, chelators of Fe2+, Fe3+ and Mn2+ ions, inhibited collagen biosynthesis in organ culture of chicken embryo tibiae. Both substances inhibited the in vitro hydroxylation of [14C]Pro-labelled protocollagen by protocollagen proline hydroxylase. A decreased incorporation of [14C]-D-glucosamine into glyco- and/or muco-proteins was found under the effect of the two drugs. Dihydralazine, a cationic compound, was bound to DNA and acid mucopolysaccharides (glycosaminoglycans), forming an insoluble complex. Both substances were bound to serum alpha 2-globulin. Subcutaneous injections of dihydralazine in rats produced a local as well as a general toxic effect.
Dermatological conditions characterized by dermo-epidermal separation, basal lamina discontinuity, multiplication, and thickness variability, and/or irregularity of the subepidermal space are discribed. Pathological changes of the dermo-epidermal junction are considered to be destructive or reproductive. Both may appear in combination. Destructive processes may be relfected by dermo-epidermal separation. Epidermal cells and/or dermal connective tissue appear degenerated. Thickening of the lamina may occur by reactive hyperproduction or by precipitation of pathological materials. Reproductive processes of the junction originate in the epidermal cells and are reflected in multilayering of the basal lamina. Interruption of the lamina and irregularity of the subepidermal space often precede these phenomena.
Low Hyp and Hyl values were found in psoriatic lesions. Treatment with PUVA achieved a return to normal values. No effect of PUVA on the collagen of uninvolved skin of psoriatic patients could be demonstrated after 4 months. There were no age-related differences in the content of Hyp and Hyl between samples of uninvolved skin of psoriatics.
Urinary excretion of proline and hydroxyproline was studied in five groups of subjects, viz. controls, pituitary dwarfs, familial dwarfs, patients with fibrodysplasia ossificans progressive and patients with generalized scleroderma. The ratio Pro/Hyp in the urinary fraction precipitated with 5 parts of acetone (1 + 5 fraction) was close to one in children and youngsters in all the groups, while in adults it was higher than two. Total Pro/Hyp does not give an accurate index of age.
Amyloid masses were found in the dermis of two brothers suffering from primary amyloidosis. The masses consisted of fibrils, composed in turn of twin hollow filaments of amyloid. An amyloid filament appeared as a 3 nm thick lucent core with a 2 nm thick wall. Occasionally 4--6 filaments were packed together in one fibril. The twin filaments were slightly twisted, with a twisting angle of 2.5 degrees and a coiling pitch of 1 160 nm. Wavy shapes of amyloid fibrils were also seen in elastic fibres. Amyloid fibrils were found in elastic fibres, under the basal lamina of the epidermis, sweat gland epithelium and Schwann cells; also around perineural cells, perivascular cells and, in one of the brothers, in collagen fibril bundles. No amyloid fibrils were found under the endothelial basal lamina. It would appear that amyloid fibrils are pathological fibrils belonging to the elastic fibre-basal lamina system.
Long-term treatment of patients with generalized progressive scleroderma by means of inhibitors of connective-tissue biosynthesis brings about total or subtotal regression of dermal sclerosis in 40.8%, partial regression in 33.1%, arrest of progression without regression in 14.8%, while in 11.3% it had no effect whatsoever. The drugs used were D-penicillamine, benzyl-penicillin-diethyl-aminoethylesterhydro-iodide, glutamine, hydralazine, chlorpromazine, L-dopa, diphenylhydantoin, and corticosteroids. Disease activity before, during and after treatment was indicated by the urinary fractions of high-molecular hydroxyproline and hydroxylysine containing peptides and of uronic acid, break-down products of collagen and acid glycosaminoglycans of connective-tissue ground substance. The prospects were better for young patients than for old, for those with a short history than for the longstanding disease cases, and for those having a large total dose than for those who had less. If left untreated, scleroderma progresses inexorably.
Two patients with fibrodysplasia ossificans progressiva (FOP) were treated with disodium etidronate, a disodium salt of ethane-1-hydroxy-1, 1-diphosphonic acid (EHPD) for two years; both had multiple ectopic ossifications of connective tissue. Regular follow-up showed no improvement in joint movement whilst laboratory examination revealed an increase in the serum phosphorus level. Serum calcium and urinary phosphorus excretion remained within normal limits. The urinary calcium excretion varied with the dose of EHDP. X-ray examination showed significant reduction in size and density of the ectopic ossifications, while the density of bones during and after EHDP therapy remained normal. Development of new ossification was inhibited in the active phase of the disease. Suspected side-effects of the drug were occult blood in stools, skin petechiae, and amenorrhoea. Previous reports on the EHDP treatment of disorders with ectopic ossification are summarised.
Increased urinary output of total hydroxyproline, hydroxylysine and uronic acid was found in two patients suffering from fibrodysplasia ossificans progressiva. Before treatment of one of the patients, the high molecular weight peptide fraction deriving from newly synthesised collagen was particularly increased. Treatment with disodium etidronate (diphosphonate) reduced the values. The urinary values of sodium, potassium and calcium were also depressed during treatment, and, in both patients, serum phosphate was high, while serum calcium was normal. The hydroxyproline and hydroxylysine contents in skin and bone of FOP patients did not differ from controls, while ectopic ossifications showed a considerable increase in hydroxylysine in relation to normal bone.
The effect on protocollagen proline hydroxylase of drugs reported to be capable of inducing the lupus erythematosus syndrome and in some way acting on connective tissue and inflammation was studied in an in vitro system for the hydroxylation of 14C-Pro-labelled protocollagen. Some derivatives were also studied. It was found that benzoic acid and phenothiazine derivatives, hydroxyphenols, (+)catechin, beta-amino propionitrile, certain B vitamins, dihydrazinophthalazine, cysteine and dimethylcysteine were inhibitors of PPH. The chelation of Fe2+ions by the compounds mentioned is suggested to be essential.
The effect of (+)catechin on connective tissue was studied in organ cultures of chick embryo tibiae and after in vivo injection in rats and mice. Collagen biosynthesis and hydroxylation of 14C-Pro-labelled protocollagen in vitro by protocollagen proline hydroxylase (PPH) were inhibited. In vivo, a slight decrease in the biosynthesis of collagen and in the PPH activity in skin of rats and mice was noticed as an effect of (+)catechin. No effect of the drug was observed on the incorporation of 14C-D-glucosamine by chick embryo tibiae. Increased urinary excretion of acid mucopolysaccharide metabolites by the mice injected with (+)catechin was observed.