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G Röckelein

Publications and source records attributed to G Röckelein.

34 records · Page 2Linked to original sources
PubMed1988

Scanning electron microscopic investigations of the human umbilical artery intima. A new conception on postnatal arterial closure mechanism.

Umbilical cord arteries were investigated using a scanning electron microscope using different methods of preparation: Perfusion of one artery under pressure from a 100 cm water column caused artefacts and the preparatory work took at least 10 min after delivery. To shorten this time fully patent umbilical cords were double clamped and fixed immediately after birth. However, the removal of blood after fixation caused the endothelial layer to be lost. Therefore umbilical cords were double clamped, snap frozen and stored in liquid nitrogen until preparation. The endothelial lining of the fully patent umbilical artery at birth is composed of longitudinally arranged, spindle-shaped cells, connected by cellular junctions. The basement membrane contains numerous gaps. Because of these gaps postnatal vasoconstriction causes herniation of the subendothelial myofibroblasts forming subendothelial vacuoles. The vacuoles produce displacement of the endothelial cell cytoplasm towards the vascular lumina resulting in protuberances and blebs on the endothelial cells. Rupture of vacuoles leads to crater-like injuries. Beneath the basement membrane a thin layer of myofibroblasts is arranged longitudinally. Oblique or transversely ordered bundles of myofibroblasts are interposed at wide and irregular intervals. These transverse bundles are able to trigger localized contraction rings called "folds of Hoboken", the initial stage of postnatal arterial closure.

Basement Membrane↗
PubMed1988

[Cholaemic placentosis--a contribution to metabolic disorders of the placenta].

The deposition of bile substances produces intracellular metabolic disorders in the organs so affected. Since severe cholaemia is rare in pregnancy, similar disorders of the placental cells have been not discussed up to now. We report on morphological observations in a placenta of a stillbirth in the middle of pregnancy. Bile substances are deposited in the syncytiotrophoblast and Hofbauer cells, pointing to the probable function of the Hofbauer cells as macrophages.

Adult↗
PubMed1988

Risk factors of hepatocellular carcinoma in Germany: hepatitis B or liver cirrhosis?

In a retrospective study, 42 out of 44 cases of hepatocellular carcinoma were investigated immunohistochemically for chronic hepatitis B infection. Surface antigen was found in the liver tissue of only 4 of these cases. In 41 of the patients, mildly to moderately active cirrhosis of the liver was found to be underlying the carcinoma. The age distribution and case histories showed that hepatocellular carcinoma often developed from low-complication cirrhosis of long standing and of various etiologies, and must thus be considered a late complication of cirrhosis.

Adult↗
PubMed1987

[Arterial fibromuscular dysplasia as an unexpected cause of death in adults].

In a 38-year-old woman, arterial hypertension was diagnosed a few weeks before her death. She died unexpectedly before a diagnostic clarification of the cause was possible. Autopsy revealed an arterial fibromuscular dysplasia with manifestation in both common iliac arteries, both renal arteries, the celiac trunk and the splenic artery. Both renal arteries displayed stenotic dissecant aneurysms which were the cause of the arterial hypertension. As a rare and lethal complication of fibromuscular dysplasia, a ruptured saccular aneurysm was found in the splenic artery. Histologically, the vascular alterations were a combination of medical fibromuscular dysplasia (type II) and periarterial or adventitial fibroplasia (type III). On the basis of the immunohistochemical detection of abundant lysozyme-positive cells, the periarterial fibroplasia appears to be a secondary chronic granulating and cicatricial reaction and not a separate form of fibromuscular dysplasia.

Adult↗
PubMed1987

[Lipoma of the mammillary body].

A lipoma of the base of the brain, located at the right mammillary body, was unexpectedly discovered during the autopsy of a 73 year old man. Current theories concerning the development of intracranial lipomas are reviewed.

Aged↗
PubMed1987

[Nematode-induced eosinophilic intestinal granuloma. Case report].

The eosinophilic granuloma of the gastrointestinal tract was in recent years observed more frequently in infections with larvae of the herring-roundworm Anisakis. The associated symptoms are similar to those of acute appendicitis. Proof of a worm within the granuloma is usually easy, where as the classification to individual species is difficult, since the larva mostly occurs as a largely decomposed corpus. Due to the long period between infection and detection of the eosinophilic granuloma patients often do not remember the origin of infection.

Adult↗
PubMed1985

[Bacterial infection of an Ionescu-Shiley bioprosthesis. Morphologic studies].

Bacterial inflammation associated with artificial cardiac valves is a rare complication after valve replacement but is burdened with a high lethality. Whereas in the case of mechanical valves the infection involves the body's own tissues, bacterial colonisation of valves made of prepared biological material can also occur. The morphology of the bacterial inflammation was examined in a case of early postoperative endocarditis. Although the bacterial infection in the paravalvular tissues resulted in a purulent inflammation, the Ionescu-Shiley-bovine bioprosthesis remained free of inflammatory cells despite extensive vegetative bacterial growth.

Aged↗
PubMedDate not supplied

[Three-dimensional analysis of the tunica media of umbilical arteries. Scanning electron microscopy study].

The three-dimensional media structure of the umbilical arteries in their various functional states has up to now been object of numerous investigations, which are predominantly based on light-microscopic findings and have come to extremely differing results. For that reason the electron microscope method with an optically higher resolution was chosen for this thesis. In total, 20 umbilical cords were recovered, and in each case one of the two umbilical cord arteries was kept in a condition of non-contraction by means of perfusion fixation immediately after the omphalotomy. After the necessary preparation longitudinal, diagonal and cross-sections of both non-contracted and fully contracted umbilical arteries as well as of the folds of Hoboken, which occur in the arteries postnatally, were investigated by the scanning electron microscope. During this examination the following findings were made: The media in the wide umbilical cord artery consists of two layers. The outer layer accounts for some three quarters of the wall and is composed of lamellae of parallel muscle fibres which surround the vessel alternatively in gently rising and falling thread-like turns. The inner layer accounts for the remaining quarter and also consists of lamellae the thread-like turns of which, however, run at a much higher pitch. Exactly subendothelial, a very thin layer of irregularly arranged fibres with longitudinal main direction can be clearly identified. The folds of Hoboken are caused by local media contraction in the course of which the outer media restructures itself, thus being the main carrier of the fold.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMedDate not supplied

[Ultrastructural studies of vacuole formation in arterial chorionic vessels of the mature human placenta].

The so called endothelial vacuoles of the human fetal stem arteries are formed by contraction of the tunica muscularis media. The cytoplasm of the smooth muscle cells prolapses through gaps of the basal membrane, found in areas of myoendothelial junctions, into the intima. Perfusion with fixative immediately after delivery prevents the formation of the vacuoles.

Arteries↗
PubMedDate not supplied

[Immunohistochemical studies of the HPL concentration in the mature human placenta].

The differences of HPL-concentration in different sections of the placenton are shown in twenty placentas by means of immunocytochemistry. The less mature villi of the plascenton centre demonstrate a lower concentration of HPL as the placenton periphery. The X-cells of the basal plate are recognised of fetal origin because of their HPL content.

Female↗