Biomedical subjects

W Jungkunz

Publications and source records attributed to W Jungkunz.

17 recordsLinked to original sources

PubMed1994

Immunohistochemical characterization of the 'intimal proliferation' phenomenon in Sneddon's syndrome and essential thrombocythaemia.

Cellular changes were immunocytochemically characterized in skin vessels of five patients with idiopathic generalized racemose livedo (Sneddon's syndrome), and one patient with localized racemose livedo associated with essential thrombocythaemia. Antibodies against alpha-smooth muscle-actin, tropomyosin, desmin, vimentin, factor VIII-related antigen, human endothelial cells (CD31), human macrophages (CD68), and HLA-DR positive cells (CR3/43) were used. Conventional light microscopy showed, in all cases, intimal thickening of ascending arteries and arterioles as a result of an accumulation of cells and extracellular hyalinized material. None of the specimens showed infiltration with polymorphonuclear leucocytes or macrophages. The cells in the region of the intimal hyperplasia showed intense positive immunostaining for alpha-smooth muscle actin and tropomyosin. Staining for the intermediate filament desmin was localized to the resident smooth muscle cells of the media, whereas staining for vimentin was found in all types of cells in both the intima and media. Positive immunostaining for factor VIII-related antigen and CD31 was strictly confined to the endothelial cells lining the narrowed lumina of the vessels. No positive staining with either antibody was observed in totally occluded vessels. Cells in the subintimal space did not show reactivity for CD68 in any of the specimens, but two cases showed solitary cells with positive staining for HLA-DR in this region. There were no differences in staining pattern between Sneddon's syndrome and essential thrombocythaemia with any of the antibodies. Our results support the assumption that the 'intimal proliferation' in both diseases is caused by colonization of the subendothelial space with contractile cells of possible smooth muscle origin.(ABSTRACT TRUNCATED AT 250 WORDS)

Actins↗

PubMed1994

Carbonic anhydrase is abundant in fenestrated capillaries of cherry hemangioma.

A strong correlation has been found between carbonic anhydrase (CA) activity and fenestrations in juxtaepithelial capillaries of several tissues, including psoriatic lesions of human skin. In the present study we demonstrate that the majority of the capillaries in cherry hemangiomas are fenestrated and histochemically react CA positively. Obviously the occurrence of CA in these capillaries corresponds to the fenestrations of venous capillaries, which are numerously revealed by electron microscopy. In normal undiseased skin no capillary staining for CA was observed. Therefore in a large proportion of the capillaries of cherry hemangiomas the correlation between fenestrations and CA activity also exists. We suggest that the histochemical demonstration of CA activity might serve as a sensitive and simple marker for fenestrated capillaries in skin tissue.

Adult↗

PubMed1992

Age-related loss of ciliary muscle mobility in the rhesus monkey. Role of the choroid.

Ciliary muscle topography was studied in rhesus monkey eyes (aged 6 to 29 years) bisected meridionally through cornea and optic nerve head. Half of each eye was incubated in atropine sulfate, the other in pilocarpine hydrochloride, and both were then processed for histologic study. Several ciliary muscle sections from the original cut margin and the middle of the half eyes were traced and compared quantitatively. In sections from the middle, where the attachments of the muscle were presumably intact, the pilocarpine effect on ciliary muscle topography was lost with age. In sections near the cut margin, where some of the posterior attachments were disrupted and the choroid had detached from the sclera, the pilocarpine effect persisted with age. These findings suggest that loss of ciliary muscle movement with age is caused by decreased compliance of its posterior attachment.

Aging↗

PubMed1992

Increase in types IV and VI collagen in cherry haemangiomas.

The capillaries in cherry haemangiomas show perivascular hyalinized sheaths. In order to clarify the nature of this sheath material, the extracellular matrix of cherry haemangiomas from 20 normal volunteers (age range 30-64 years) was investigated using immunohistochemical and electronmicroscopical methods. Antibodies against collagen types III, IV and VI and laminin were used. Hyaluronic acid was visualized using the hyaluronic acid binding region of the cartilage proteoglycan as ligand. Electronmicroscopically, the sheaths contained multilaminated basement membrane-like material, collagen fibres 20-25 nm thick with a periodicity of 67 nm and broad-banded aggregates with a periodicity of 100 nm (zebra bodies or fibrous long-spacing fibres). Immunohistochemically, type IV collagen was stained throughout the whole sheath material. Staining for laminin was more confined to the endothelial side of the sheath. Intense staining for type III collagen and hyaluronic acid was found in the connective tissue of the subpapillary layer and between the cherry haemangioma capillaries. Much weaker staining for type III collagen and no staining for hyaluronic acid were found invariably in an area 4-10 microns thick directly around the capillaries. Both sheath material and intercapillary connective tissue of the haemangiomas showed pronounced staining for collagen type VI. Immunogold staining revealed that type VI collagen was localized to microfibrils 5-6 nm thick and to the broad-banded aggregates with 100 nm periodicity. These findings further underline the assumption that the broad-banded aggregates consist of type VI collagen.

Adult↗

PubMed1992

Carbonic anhydrase--a marker for fenestrated capillaries in psoriasis.

A strong correlation between capillary fenestrations and the demonstration of carbonic anhydrase (CA) has previously been shown. In the present histochemical study we sought to determine whether CA could serve as a marker for fenestrated capillaries in psoriasis. In normal human skin capillary staining for CA was found only in the fenestrated capillaries of the perifollicular and periglandular plexus. In psoriatic skin lesions, however, the intrapapillary capillaries also reacted for CA. From ultrastructural investigations it is known that these capillaries are fenestrated. Our findings have shown that there is a strong correlation between fenestrated and CA-positive capillaries in normal human skin as well as in the lesional skin of psoriatics. Therefore, the demonstration of CA activity may serve as a specific and sensitive marker for fenestrated capillaries in psoriasis using an uncomplicated method, which makes it possible to detect numerous fenestrated capillaries in a single histological section.

Adult↗

PubMed1991

Posterior attachment of ciliary muscle in young, accommodating old, presbyopic monkeys.

The authors studied the posterior attachment of the ciliary muscle in seven young (3-10 yr) and five old (26-34 yr) rhesus monkeys by light microscopy and electron microscopy. Posterior attachment of the muscle bundles consisted of elastic tendons, exclusively. The elastic tendons were continuous with the elastic lamina of Bruch's membrane and were also connected by smaller elastic fibers to an elastic meshwork that surrounds the pars plana vessels. In some areas, the tendons formed focal contacts with the endothelial cells. The authors found that in old eyes, the tendons and the elastic fibers of the posterior ciliary body showed pronounced structural changes. The tendons appeared thickened, showed increased amounts of associated microfibrils, and were surrounded by dense layers of thick collagen fibrils. An increased amount of collagen fibrils was also seen between the elastic layer of Bruch's membrane and the pigmented epithelium. A mechanical link between those collagen fibrils and the elastic fibers is suggested by the presence of osmiophilic points of contact. The age-related increase in elastic fibrillar material could cause decreased compliance of the posterior insertion of ciliary muscle and could be an essential factor for presbyopia in rhesus monkeys.

Accommodation, Ocular↗

PubMed1989