Ultrastructure of psoriatic epidermis.

The ultrastructure of human affected and unaffected psoriatic epidermis was studied in skin biopsies from 5 patients and 3 normal controls. Transmission electron microscopic investigations revealed abnormalities in all cell layers of the affected epidermis. Common to psoriatic keratinocytes from affected epidermis was the reduction of tonofilaments.

Surface ultrastructure of cultures of affected psoriatic keratinocytes, unaffected psoriatic keratinocytes and normal keratinocytes.

The surface structure of 11-12 days old cultures from biopsies of normal skin and uninvolved psoriatic skin was investigated by scanning electron microscopy. The keratinocytes formed flat, thin, and well-organized layers of elongated, tightly apposed cells. Newly-formed cells with few and short microplicae and microvilli were seen at the colony periphery.

A medieval case of metastasizing carcinoma with multiple osteosclerotic bone lesions.

The skeleton of a mature male from the Middle Ages, excavated in Svendborg, Denmark, presented multiple osteosclerotic metastases probably of a carcinoma of the prostate gland. This diagnosis is based on radiographic and histological studies. Coexisting gross changes of the spine are identified as vertebral osteophytosis.

Fetal arterial involvement in Behcet's disease: an electron microscope study.

A fetus, 16 weeks old, was removed by hysterotomy from a patient suffering from Behcet's disease. The patient received systemic steroids during pregnancy. Electron microscopy of the fetal thoracic aorta revealed edema of the sub-endothelial space and of the luminal part of the tunica media, as well as a pronounced rarefaction and disarrangement of the smooth-muscle cells.

Involvement of post-capillary venules in Behçet's disease: an electronmicroscopic study.

In Behçet's disease, severe pathological changes are observed in the post-capillary venules, indicating that the venous side of the circulation is generally involved. It is proposed that one of the initial pathological changes is multiplication of the basal lamina surrounding the post-capillary venule.

The ultrastructure of the dermo-epidermal junction in lichen planus.

The ultrastructure of the dermo-epidermal junctional area in biopsy material from 5 patients suffering from lichen planus has been studied during treatment with steroids. Tannic acid was used on the tissue blocks in order to provide high and diversified contrast for electron microscopy. The changes observed in the basal cells consisted mainly of degeneration of the mitochondria and disorganization of the tonofilaments.

Acrokerato-elastoidosis: a case report.

Acrokerato-elastoidosis belongs to the group of diffuse palmo-plantar keratoses without associated symptoms. We report a 25-year-old man who has had typical skin lesions for 5 years. The histopathological changes are described.

Ultrastructural visualization of concanavalin A binding receptor sites in neoplastic and non-neoplastic transitional cell epithelium of the human urinary bladder.

Concanavalin A binding receptor sites in non-neoplastic and neoplastic transitional cell epithelium from tumour-bearing human urinary bladders were mapped ultrastructurally following successive incubation of vibratome slices with concanavalin A, peroxidase and diaminobenzidine. In the normal epithelium the reaction product was found in the plasma membranes of the basal cells. Some areas of the endoplasmatic reticulum and the discoid vesicles were reacting in all cell layers.

Observations on the association of annulate lamellae with vinblastine-induced paracrystals in tumour cells in vitro.

Tumour cells in vitro responded to prolonged treatment with colchicine with the formation of annulate lamellae. Following the colchicine treatment, paracrystals were induced with vinblastine. A close association of annulate lamellae with vinblastine-induced crystals was observed.

Surface structure of tooth germs from newborn infants: a light and scanning electron microscopical study.

Tooth germs from the mandibles of 5 stillborn infants were examined by scanning electron microscopy and light microscopy in order to investigate the surgace structure at different stages of mineralization. The surface of the completed enamel of the incisal third of the incisors was smooth, indicating that amelogenesis was at an end. The interface relief between ameloblasts and enamel matrix on the remaining part of the incisors, and on the forming cusps, was characterized by numerous deep pits caused by the Tomes' processes of the ameloblasts.

Further evidence for the existence of intralobular nerves in the rat liver.

In a recent study (Skaaring and Bierring, 1976) we found cholinesterase-positive nerve-like structures in the lobules of rat liver, and scanning electron microscopy revealed cords having a distribution pattern similar to that of the cholinesterase-positive structures. To obtain further evidence for an intralobular nerve supply the methods of cobalt and Procion Yellow nerve staining (Stretton and Kravitz, 1968; Iles and Mulloney, 1971; Pitman, Tweedle and Cohen, 1972) were adapted, iontophoretic introduction of the dyes being attempted through cut axonal ends in the surface of small excised blocks of rat liver.

Surface topography of the healthy and diseased transitional cell epithelium of the human urinary bladder.

51 biopsies from healthy and diseased epithelium from human urinary bladders were examined by scanning electron microscopy. The luminal surface of the cover cells was marked by microvilli and microplicae. The replacement of the cover cells takes place by simple desquamination.

On the intrinsic innervation of normal rat liver. Histochemical and scanning electron microscopical studies.

With the Bodian method stained fibers were observed in the lobules of the rat liver and with the modified Karnovsky and Roots thiocholine method cholinesterase (presumably acetylcholinesterase (AChE))-positive nerve fibers were found in a pattern similar to that of the Bodian-stained fibers. The AChE-positive nerve fibers form a network in the liver lobules in close relation to hepatocytes and sinusoids. Fluorescent varicose nerve fibers demonstrated by the glyoxylic acid and Falck-Hillarp fluorescence methods were found only in the interlobular spaces associated with vessels.

LYMPHOID ORGANS AND NORMAL GAMMA-GLOBULIN IN THE RAT.

Serum gamma-globulin was determined in adult rats several months after total thymectomy, subtotal splenectomy, or a combination of total thymectomy, subtotal splenectomy, and subtotallymphadenectomy. The thymus apparently is of little importance in the production of normal gamma-globulin, but it may influence the production of albumin because a reduction of serum albumin was only seen in groups where thymectomy was performed. The spleen seems to produce normal gamma-globulin to a greater extent than lymphoid tissue elsewhere in the body.