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Biomedical subjects

W Thoenes

Publications and source records attributed to W Thoenes.

At least 55 records · Page 3Linked to original sources
PubMed1986

Morphology of the coronary arteries after combined thrombolysis and percutaneous transluminal coronary angioplasty for acute myocardial infarction.

Autopsy findings are reported for 6 patients who died early (8, 9, 12, 13 and 14 days) or late (52 days) after combined thrombolysis and percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction. Morphologic changes in the coronary arteries at the site of revascularization included injury to the inner portion of the arterial wall (intimal splitting, subintimal dissection, medial tears and submedial dissection) and necrosis of medial smooth muscle cells. Residual mural thrombi and thrombotic reocclusion were noted within the arterial lumen. There was a beginning neointima formation in all patients who died early and a reobstructing neointima proliferation in the patient who died late after PTCA. The results of this study support the suggestion that both rupture and dissection of the inner arterial wall and necrosis of the tunica media resulting from irreversible dilatation of the grossly intact outer layers are the most important mechanisms of PTCA. Response to arterial wall injury after PTCA is a neointima formation leading to covering of mural thrombi and thrombogenic intimal, medial and adventitial substances and smoothing of the luminal surface. Large residual mural thrombi and excessive neointimal proliferation may cause restenosis within a few weeks.

Aged↗
PubMed1986

[Acute necrotizing pancreatitis. Synoptic observation of clinical and pathologic-anatomical findings].

In 95 patients with acute necrotising pancreatitis the clinical severity of the disease was compared with morphological criteria of operative specimens. In addition, various morphological phenomena, typical in acute and chronic pancreatitis, were investigated in 3 aetiologically different groups. In these groups pathohistologic alterations, associated with aetiological factors, were seen frequently. Furthermore, there was a good correlation between classifications according to gravity criteria in the assessment of the underlying disease. About 90% of cases clinically classified as acute pancreatitis proved, on the basis of the morphology, to be chronic recurrent pancreatitis. It thus follows that "genuine" acute pancreatitis is a rather rare syndrome.

Acute Disease↗
PubMed1986

Hepatitis A-like non-A, non-B hepatitis: light and electron microscopic observations of three cases.

To date, three types of NANBH have been distinguished by epidemiological, clinical and experimental data. We examined the liver biopsies of three patients with an acute NANBH resembling hepatitis A from the infection route, incubation period and clinical course. The liver biopsies revealed lesions with a portal and periportal predominance, thus also exhibiting parallels with hepatitis A on the histopathological level.

Adult↗
PubMed1986

Histopathology and classification of renal cell tumors (adenomas, oncocytomas and carcinomas). The basic cytological and histopathological elements and their use for diagnostics.

The term renal cell tumors (adenomas and carcinomas) subsumes the tumors deriving from the uriniferous tubule epithelium of the kidney. Precise analysis shows that the renal cell tumors display different cell types which build up the individual tumor alone or in combination with each other. Three categories of basic elements are distinguished in the characterization of renal cell tumors: Cytological elements = tumor cell types: Clear, chromophobe, chromophilic (basophilic, eosinophilic), oncocytic, spindle-shaped/pleomorphic. Histological elements = growth patterns: Compact, acinar (nest-like), tubulopapillary (tubular, papillary), cystic. Cytological grading of malignancy: G I, G II, G III; mainly based on the degrees of nuclear atypia. The cytological features are given priority compared to the histological growth forms for classification of renal cell tumors. However, the latter are not to be neglected in the overall evaluation of a tumor. A classification of renal cell tumors is suggested and the result of its application in 510 renal cell carcinomas and oncocytomas is presented. On this basis and in connection with the cytological grading, a more precise prognostic evaluation of the renal cell carcinomas is expected.

Adenoma↗
PubMed1986

[Renal cell carcinoma--a classification based on cytomorphological criteria].

535 human renal cell carcinomas were classified using a classification system based on defined tumor cell types. The following tumor cell types were distinguished: clear cells (with variants: clear cell-eosinophilic, plasma-rich), chromophobe cells (with variants: eosinophilic, relatively light), chromophilic cells (basophilic, eosinophilic), spindleshaped/-pleomorphic cells. A group "still unclassified" is added. This classification largely rejects the term "granular" (which as a rule was combined with "eosinophilic"), because in our view this term referred to a heterogenic group of variants of different cell types. A cytological grading--based on nuclear morphology--is conducted using 3 grades (GI - III). Preliminary results from follow up studies (survival rates, metastases) suggest that this classification may also have clinical importance for tumor prognosis.

Adolescent↗
PubMed1985

Human chromophobe cell renal carcinoma.

Twelve renal cell carcinomas composed of "chromophobe" cells are described. This is the first report of renal chromophobe cell tumors in humans neoplasms of this cell type having been described previously only in experimentally induced adenomas in animals. By light microscopy chromophobe cells have slightly opaque or finely reticular cytoplasm when stained with haematoxylin and eosin. They may be distinguished from the clear cells of hypernephroid renal cell carcinomas by the strongly positive reaction of their cytoplasm with Hale's (1946) colloidal iron method and the weaker positive reaction with alcian blue. Vesicular structures, often containing internal vesicles, and possibly derived from the endoplasmic reticulum or from mitochondria are visible electronmicroscopically. Glycogen is present to a variable but slight extent so that it is usually detected only by electron microscopy. The twelve renal cell carcinomas described were composed entirely of chromophobe cells. They were derived from a series of more than 500 adult renal cell carcinomas giving a frequency of approximately 2%. To avoid confusion the descriptive term "light cell" should be discarded and replaced by either "clear cell" or "chromophobe cell" as appropriate, since it is assumed that chromophobe cell tumors have a different derivation from clear cell and other renal cell carcinomas. They may also have a different prognosis although this has not yet been established.

Adult↗
PubMed1985

Rapidly progressive glomerulonephritis in IgA/IgG cryoglobulinemia.

Mixed IgA/IgG cryoglobulins were found in the serum of a 48-year-old man suffering from rapidly progressive glomerulonephritis (RPGN) with crescent formation. The type-II cryoglobulins were composed of monoclonal IgA1-kappa and polyclonal IgG, with the IgA possessing antibody activity against the IgG. The RPGN was of the immune complex type with granular deposits of IgA, IgG, and C3 on immunofluorescence microscopy and preponderant subendothelial deposits on electron microscopy. Occluding protein thrombi could be demonstrated in several glomerular capillary loops. Removal of the cryoglobulins from the patient's serum by plasmapheresis and immunosuppression was paralleled by a remarkable improvement in renal function with fall of serum creatinine values from 13.6 mg/dl (1,202.2 mumol/l) to 2.8 mg/dl (247.5 mumol/l), a resolution of the glomerular lesions, and clinical improvement as well. Our observations suggest that the crescentic glomerulonephritis may be due to an immune complex-like deposition of the cryoproteins. We conclude that crescentic glomerulonephritis in IgA/IgG cryoglobulinemia has to be considered as an autoimmune form of RPGN.

Biopsy↗
PubMed1985

Differentiation of granuloma cells (epithelioid cells and multinucleated giant cells): a morphometric analysis. Investigations using the model of experimental autoimmune (anti-TBM) tubulo-interstitial nephritis.

Morphometric analysis disclosed distinct differences between blood monocytes, tissue monocytes (i.e. immature macrophages), epithelioid cells and multinucleated giant cells as well as phagocytic macrophages (i.e. mature macrophages) in the granuloma model of autoimmune (anti-TBM) tubulo-interstitial nephritis. The numerical density of lysosomes decreased slightly in tissue monocytes compared with blood monocytes but showed a pronounced increase during the formation of epithelioid cells. The lysosomal compartments of epithelioid cells and multinucleated giant cells resembled each other very closely, but the giant cells obviously produced additional lysosomes of small diameter (80-120 nm). Phagocytic macrophages displayed a total numerical density of lysosomes similar to that of tissue monocytes but the mean diameter of the lysosomes was markedly greater. Thus the volume density of lysosomes was highest in phagocytic macrophages. The blood monocytes exhibited the smallest lysosomal compartment. In tissue monocytes, epithelioid cells, and multinucleated giant cells the volume densities of the lysosomes were greater than in blood monocytes and remained relatively constant because the increase in numerical density was counterbalanced by a decrease in mean granule diameter. We found only minor differences in mitochondrial volume densities among the five cell populations. The shape of the mitochondria, however, changed steadily from short rotational ellipsoids in the blood monocytes to rather elongated and slender bodies in the multinucleated giant cells. The results suggest that epithelioid cells and multinucleated giant cells are active cells which may contribute by their specific performances, to the immunologic microenvironment of the granuloma.

Animals↗
PubMed1984

Electron microscopic observations on primary hepatocyte cultures infected with herpes simplex virus types I and II.

The replication cycle of the Herpes simplex virus (HSV) strains I and II has so far been described mainly in established proliferative cell cultures. Most of the biochemical data and ultrastructural cell changes regarding the virus-cell interaction have been obtained from 'permissive' cells which allow almost unrestricted viral multiplication. It seems obvious, however, that the in vivo viral infections are not represented adequately by these experiments. In order to achieve a more realistic view of the ultrastructural events during HSV infection of adult tissue, cell cultures were prepared from adult mouse and rat livers and infected with several HSV strains. Established 'permissive' cell lines (BHK and RK cells), served as controls. Although the main principles of viral attachment, replication and release of viral particles, were similar in hepatocytes and proliferating cells, marked differences were observed regarding the better preservation of the nuclear structures, the lower replication rate of viruses, the hypertrophy of the endoplasmic reticulum, and the changes in the Golgi apparatus. Summarizing, it can be stated that hepatocytes infected by HSV in cell culture display the well known general features of adult cells infected by viruses in vivo.

Animals↗
PubMed1984

Endocytotic activity in epitheloid and Langhans' giant cells. Tracer studies with ferritin in the tubulointerstitial (anti-TBM) nephritis model.

In the experimental tubulo-interstitial (anti-basement membrane) nephritis in the rat, electron microscopic studies after the in vivo microinjection of native ferritin in areas of granulomatous inflammation near the surface of the kidney indicate that epitheloid and multinucleate Langhans' giant cells are capable of endocytosis and particularly of micropinocytosis. This suggests the possibility that endocytotic activities as well as secretion phenomena are important in the immune defense mechanisms linked with these "specifically" developed cells.

Animals↗
PubMed1983

[An automated procedure for the determination of the malignancy of tumorous tissue changes].

The accuracy of the "Histomat", an apparatus for automated histophotometric determination of malignant or benign tissues, was used on samples from 235 breast tumours (94 malignant and 141 benign tumours). Analysis of the measured data, using the schema developed by the manufacturer (Hytec), showed that in tumours of the breast this type of histophotometric analysis cannot distinguish between benign and malignant tissue changes. Its diagnostic use is therefore not justified.

Automation↗
PubMed1983

[Familial Mediterranean fever with amyloidosis. Recent pathogenetic and therapeutic aspects].

Familial Mediterranean fever was diagnosed in a 34-year-old Turkish patient with severe nephrotic oedema. Immunohistochemical classification of a biopsy specimen showed amyloidosis of the AA-type. There was a definite increase of serum amyloid-A-protein (SAA). The typical recurrent fever, attacks of abdominal pain with symptoms of subileus and joint swelling could be treated successfully with colchicine, the oedema with diuretics. The progression of renal failure and proteinuria as indicator of the degree of amyloid-induced renal damage remained unaffected by this treatment. With dimethyl-sulfoxide (DMSO) a marked improvement in renal function and a lowering of the SAA level could be achieved. Thus this treatment inhibits the progression of amyloidosis of the AA-type in Mediterranean fever and may be considered for other forms of AA-type amyloidoses. It is possible that the lowering of the SAA-serum concentration and the improvement of renal function is due to an antiphlogistic effect of DMSO, the mechanism of action of which is so far unknown.

Adult↗
PubMed1983

Manifestation and ultrastructural typing of amyloid deposits in the heart.

Using light and electron microscopy, 65 cases of amyloid deposits in the heart were examined. Five different groups were distinguished: I. isolated atrial amyloidosis, II. senile cardiac amyloidosis, III. cardiac amyloid accompanying chronic infections and tumors, IV. cardiac amyloid accompanying plasma cell dyscrasia, V. idiopathic cardiac amyloidosis. Seen structurally, no principal differences in the precise localization of the amyloid deposits were found in any of the groups investigated. Amyloid is always deposited in the vicinity of cells with myocytic cell differentiation (i.e. the heart muscle cells, non-striated muscle cells of the vessels), whereby the relevant basement membranes serve as conductors. A systematic relationship between amyloid and the collagenous fibers of the interstitium or the tunica adventitia of the vessels could not be demonstrated, which shows the concept "pericollagen" to be inadequate for the morphological characterization of amyloid deposits in the heart. Whereas for group I a localized mechanism for the production of amyloid must be considered, in the case of groups II-V a vascular principle expression of a generalized amyloidosis seems to be the major factor. The question of the differing concentration of amyloid deposits in the heart suggests that localized factors (e.g. changes in the myocytic basement membranes) and quantitative changes of the amyloid-building proteins may also be important.

Adolescent↗
PubMed1983

Angioma-like pseudometamorphosis in Wilms' tumors subjected to preoperative radio- and chemotherapy.

Six Wilms' tumors (stage III-V), which had undergone preoperative irradiation and chemotherapy, were examined histologically. While mesenchymal and differentiated epithelial tumor elements were preserved to a large extent, blastemic tumor structures were almost completely lacking. Instead, pseudoangioma-like structures similar to cavernous hemangioma prevailed. As demonstrated by transitional pictures, the pseudoangioma-like pattern is a result of the fact that blastemic tumor elements are replaced by blood after therapy-induced necrosis and lysis. The clinical advantages of preoperative treatment are briefly discussed, especially for patients with advanced tumors.

Child↗
PubMed1983

The garland type of acute postinfectious glomerulonephritis: morphological characteristics and follow-up studies.

Among 44 patients with acute post-infectious GN, we found 11 cases (10 male, 1 female) displaying an immunohistologically and electron microscopically characteristic "garland pattern". Numerous sub-epithelial deposits of the "hump" type with characteristic patchiness correspond in the electron micrograph to densely packed deposits (IgG, always combined with C3, more rarely also with IgM) demonstrable immunohistologically on the peripheral loops. On the other hand, sub-endothelial, mesangial and intramembranous deposits are less prominent. Clinically, the patients have a strikingly high proteinuria. Follow-up studies have revealed that in a proportion of the patients both the clinical and the morphological findings can regress after a month long course. These are mainly younger patients. On the other hand, in another group of cases (mainly older patients) both the clinical and the morphological findings persist even after months. Within acute post-infectious GN, the "garland type" appears to form a particular group in which a large proteinuria (with or without nephrotic syndrome) and a tendency to chronicity or at least to a protracted course is present in a relatively high percentage.

Adolescent↗