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Mast cells participate in experimental calcinosis. Skin from patients with urticaria pigmentosa (cutaneous mastocytosis) calcifies in vitro. In the present report, the nature of the calcium deposit was studied by electron optical techniques. The cultured mast cells of urticaria pigmentosa skin were surrounded by a large number of round bodies with an average diameter of 200–300 nm. Most of the round bodies were membrane bounded, while a few contained lamellar structures. These bodies may represent matrix vesicles as seen in calcifying hard tissues and/or may be remnants of mast cell granules. The calcified deposits were located on the round bodies, collagen fibrils and elastic matrix. Electron diffraction and X-ray microanalysis demonstrated that the deposits consisted of crystalline calcium apatite. [ABSTRACT FROM AUTHOR]

The article cites a study, where biopsy material from patients with various types of psoriasis has been analyzed for the presence of deposits of immunoglobulin and complement by means of a direct immunofluorescence technique. Previously, little attention has been paid to the walls of the dermal vessels, where the majority of the deposits were found and are being discussed in this article. Several studies suggest that immunological factors may be of importance for the development of psoriatic lesions.

Ten cases of hepatitis B virus infection were identified among asymptomatic male homosexuals. These patients shared a number of characteristics: A subclinical origin and course of infection; Persistence of HGsAg for periods exceeding six to 25 months; Persistent GPT elevation of two to five times upper normal limit; Morphological changes in the liver with portal and parenchymal inflammation (chronic persistent hepatitis, six cases; non-specific reactive hepatitis, 2 cases; cirrhosis and acute hepatitis with signs of chronicity, one case each). HBeAg was found in six cases, anti-HBe in none. These results indicate that screening for hepatitis B should be performed whenever these individuals come under medical attention in order to detect asymptomatic chronic liver diseases and to detect these silent vectors of an infection that presently shows an increased frequency among homosexuals. [ABSTRACT FROM PUBLISHER]

The effect of the antiprotozoal drug pentamidine on the ultrastructure of the amastigote stage of Leishmania tropica was studied. The most remarkable change introduced by the treatment occurred in the kinetoplast-mitochondrion complex. All mitochondria were extremely enlarged and most kinetoplasts disintegrated into a network of fine filaments. The flagellar pocket was frequently dilated and filled with various quantities of double-membrane bounded bodies ejected from the pocket wall. The multivesicular bodies and lipid droplets were enlarged. The number of ribosomal granules decreased. Many protozoa had an irregular shape and damaged internal structure. The drug-induced changes of L. tropica are discussed in relation to similar effects previously observed in trypanosomes.

Application of suction blister transplants to leg ulcers is an alternative symptomatic treatment to split-skin grafting, i.e. "pinch-grafting". Blisters are produced by the suction device Dermovac at a suction pressure of 250-300 mmHg for 1-2 hours. The blister-roofs are cut off at the periphery and placed on the granulation tissue of the ulcer. The healing time for leg ulcers was 10-14 days. Excellent epithelialization was seen in 10 out of 12 ulcers. The advantages of the method are, that it is easy to perform, no scarring is produced, and the procedure is painless.

Deposits of complement C3 and/or immunoglobulin were found in the vessel walls and/or at the dermal-epidermal junction in skin lesions of all of 11 patients with psoriatic arthritis and guttate psoriasis. Similar deposits were seen in 6 out of 15 patients with psoriasis vulgaris. Synovial tissue available from 2 patients revealed deposits in the vessel walls.

During cultivation, the collagen fibrils of skin explants are broken down. The cells of the explants participate in this resorption. The ultrastructure of the intracellular degradation of collagen fibrils of cultured human skin has been examined. Intracellular collagen fibrils occur in fibroblasts, macrophages, smooth muscle cells and unidentifiable cells. Normal collagen fibrils are engulfed and appear within membrane-bounded tubes of the cytoplasm. Primary lysosomes fuse with the tubes. Degraded intracellular collagen fibrils are frequently present in secondary lysosomes and show decreasing diameters, filamentous splitting, loss of axial periodicity, variable stainability and cross-banded filamentous aggregates. The changes in the intracellular collagen fibrils are identical with those seen in the extracellular space. The present study demonstrates that various cell types in dermis are involved in collagen fibril degradation and that the lysosomes play an important part in the intracellular resorption.

Two female patients with oedema of the arms and legs due to contact dermatitis complicated with recurrent infections were examined. The concentrations of plasma proteins of different molecular weight in the oedema fluid (collected from suction blisters) were highly increased. Albumin outflux as measured with radiolabelled albumin from the vessels of oedematous skin was markedly decreased corresponding to a decreased lymphatic function. Treatment with benzo-pyrones for 6 months did reduce the protein concentrations of the oedema fluid, but the clinical response was disappointing.

Prolapsed tissue and removed interspace contents were obtained during hemilaminectomy for disc prolapse. The ultrastructure of the tissue was studied. Division of the material into annulus fibrosus and nucleus pulposus proved to be inaccurate. Chondrocytes were always the predominant cell type and could be classified into normal, cloning and necrotized types. Matrix vesicles were found in relation to the haloes of chondrocytes and seemed to be products of disintegrated chondrocytes. Findings of crystals in the vesicles were rare. The intercellular substance showed degraded collagen fibrils, which could be seen in spindle shaped cells as well. A dense amorphous material interpersed with collagen fibrils seemed to be a glycoprotein. A few elastic fibres were found, but without any evidence of severe degeneration. These findings represent changes occuring in cells and in the intercellular substance.

Clostridial collagenase, elastase, medium material of human skin culture, dithioerythritol and citrate buffer, pH 3.5, were applied to fresh human skin specimens. Phenomena of degradation of dermal fibrils were observed by electron microscopy.

Calcium deposits in elastic fibers of involved skin of patients suffering from pseudoxanthoma elasticum have previously been reported. In the present work, the crystalline structure and composition were studied. Involved skin was obtained from 5 patients. Bright-field and dark-field electron microscopy and selected area electron diffraction of the calcium deposits were applied. The study demonstrates calcium apatite crystals.

Among 130 male patients admitted during a 30-month period with acute hepatitis in the Copenhagen Clinic for Infectious Diseases, 31 were homosexuals. Hepatitis B virus occurred in an endemic fashion in the homosexual subpopulation while hepatitis A infection caused a small epidemic among homosexuals during the winter 1977-78. The course of these infections showed no serological or clinical differences from the findings in 38 heterosexual male patients seen during the same period.

Salpeter-induced calcium deposits in ten patients showed a close clinical and histopathological similarity to the lesions of pseudoxanthoma elasticum. By electron microscopy and selected area diffraction analyses of the calcium deposits we find the changes indistinguishable from the changes previously described in involved skin of patients suffering from PXE. Clinically our patients were compared with the fourteen patients with traumatic calcification previously described.

The ultrastructure of dermal connective tissue in two patients suffering from fibrodysplasia ossificans progressiva (syn myositis o.p.) was studied. The disorder starts with soft tissue swelling which subsequently ossify. The connective tissue of various organs may be affected. No defects in calcium metabolism have been discovered. It was intended to study the primary event which initiates the ossification. The present ultrastructural study demonstrates an accumulation of proteoglycan microfibrils as well as glycoprotein material in dermal connective tissue. Both substances are prerequisites of calcification resulting from the binding of calcium and phosphorus ions. A subsequent release of proteolytic enzymes in the tissues may be set free the bound iones and, thus, initiate mineralization.

In the present survey 3 groups of patients were studied: 95 homosexual males, 117 heterosexual males and 68 females attending clinics for venereal diseases in Copenhagen. 10 cases of hepatitis B infection were found, all in homosexual males. Chronic carriership of hepatitis B surface antigen (HBsAg) and presence of hepatitis B e-antigen (HBeAg) was demonstrated in 8 and 5 cases, respectively and liver biopsy showed chronic liver disease in 5 out of the 8 former. The prevalence rate of hepatitis B antibody was significantly higher in all patient groups than in the general population in the area. Two patients had non-B hepatitis, 1 homosexual male and 1 female, but the prevalence rate of hepatitis A antibody (anti-HAV) was not increased in the venereal clinic population. The serological tests identified certain high risk groups regarding hepatitis B infection: (1) homosexual males > 25 years with anti-HAV and a high promiscuity; and (2) heterosexual males and females > 25 years with a past history of venereal disease and clinical hepatitis. The data are compatible with the hypothesis that sexual transmission plays an important role in the spread of hepatitis B infection. It is recommended that routine serological tests for hepatitis be taken in the high risk groups of venereal clinic populations.

The ultrastructure of the amastigote stage of Leishmania tropica has been studied. The present work reports on new observations on the fine structure of the basal body, prokinosome and flagellum. The basal body is composed of a centriole-like structure and a transitional zone continuous with the proximal part of the flagellum. The centriole-like part consists of nine peripheral triplet tubules and an indistinct dense central core. The transitional zone consists of nine peripheral doublet tubules and two central cylinders. The centriole-like prokinosome is present parallel and close to the basal body. The flagellum arises from the transitional zone of the body and has the classical axoneme (9+2) structure. However, at the tip of the flagellum the central tubules are replaced by one of the peripheral doublet tubules. The ultrastructural findings, as compared with previous studies of Leishmania, are discussed.

To obtain viable cells from normal human skin, clostridial collagenase was used. Crude collagenase digestion of collagen fibres and basal lamina results in free dermal cells and sheets of epidermis. The collagenase was tested at various concentrations, solvents and incubation periods. The specimens digested were either split or full thickness skin of varying size. The optimal result was obtained by using small (3mm across) split skin pieces incubated in 2 mg/ml collagenase. The choice of solvent MEM, MEM supplemented with serum, and Tris buffer, was less important. 3 hours' incubation the epidermis was peeled off in sheets and finally dissociated by trypsin-EDTA. The corium was completely digested after 6 hours. After 6 hours' incubation no viable cells could be seen. The epidermal cells appeared mainly as polygonal cells of various sizes and a few little dendritic cells. The dermal cells had a heterogeneous morphology during the first weeks of cultivation. After 2 weeks the cells appeared as fibroblast-like cells.

To obtain pure culture of epidermal cells from small human biopsies, two different techniques were tested and compared, i.e. separation of epidermis from corium before cultivation by trypsin and suction, and after cultivation by trypsin and collagenase. The most active growth of epidermal cells was obtained by the third technique, since short-term trypsin treatment released only fibroblasts from the culture. Crude collagenase (type I) was less effective than trypsin. Collagenase type II, III and IV had no effect on fibroblast release. Neither trypsin nor collagenases dispersed epidermal cells.

Primary cultures of epidermal cells from human adult skin were dissociated by dithiothreitol (DTT) with subsequent trypsinization. After treatment with disulfide reducing agents, the desmosomes were either destroyed or showed a homogeneous ultrastructure. Trypsin separated the homogeneous desmosomes, whereas cell membranes, organelles, and nuclei remained undamaged. Trypsin did not influence normal desmosomes. A suspension of human epidermal cells was recultivated in new flasks. Two types of cells grew in the cultures--polygonal and spindle-shaped. The polygonal cells were maintained for 30 to 60 days and grew slowly. The spindle-shaped cells were leucine-amino-peptidase negative, grew actively, and were subcultured.

Collagenolytic enzymes are produced by cultured skin explants. During cultivation the acellular compartment of the dermal connective tissues is digested away. The ultrastructure of the connective tissue resorption has been studied in human skin maintained in organ culture for 2--10 weeks. The connective tissue changes are: (1) Collagen fibrils with normal axial periodicity but decreasing diameters. On cross sections these fibrils have irregular outlines, while the longitudinal sections show fibrils separated into thin bundles of filaments 40--80 A thick with preserved normal axial periodicity. (2) Cross-banded filamentous aggregations (CBFA) consisting of fine parallel filaments 25 A thick and without axial periodicity. The CBFA has 350 A thick bands at 525 A intervals. At the end of the cultivation, the CBFA are replaced by solitary filaments 25 A thick. (3) The elastic fibres show no marked changes of the amorphous matrix, while the fibrils disappear. The loss of collagen and elastic fibrils during cultivation of the skin gives direct evidence of connective tissue degradation. The described changes are discussed in relation to previous ultrastructural studies on connective tissue resorption of various tissues.