Search results for "pathology [Aging]"
showing 10 items of 1700 documents
Differentiation in medulloblastomas: correlation between the immunocytochemical demonstration of photoreceptor markers (S-antigen, rod-opsin) and the…
1989
Biopsy specimens of 66 medulloblastomas were investigated by means of S-antigen and rod-opsin immunocytochemistry. The patients were operated between 1969 and 1988 and the medical records were retrospectively evaluated to correlate the immunocytochemical features of the tumors to the course of the disease. S-antigen- and rod-opsin-immunoreactive tumor cells were found in 19 out of 66 cases. Since in the normal non-neoplastic state immunoreactive S-antigen and rod-opsin are restricted to retinal photoreceptors and a class of pinealocytes derived from photoreceptor cells, the occurrence of these proteins in certain tumor cells of medulloblastomas suggests a differentiation of these cells alon…
Morphometric Study of the Bone Marrow in Polycythemia Vera Following Interferon-Alpha Therapy
1993
Bone marrow cellularity and extent of fibrotic change were determined in nineteen patients with polycythemia vera, treated with interferon-alpha (IFN) for 1 year. The cellularity was evaluated with an interactive semiautomatic method using Leitz TAS plus microscope: in particular, number and size of megakaryocytes were evaluated after immunostaining with Y2/51 (CD 61); reticulin content was studied by light microscope with a semiquantitative method. Before IFN therapy mean cellularity was 80.5% (+/- 13.7). After 6 and 12 months mean cellularity was 75.4% and 68.4% respectively. Six months after cessation of IFN therapy the cellularity was 69.1%. A decrease of the number, density and morphom…
Different immunophenotypical apoptotic profiles characterise megakaryocytes of essential thrombocythaemia and primary myelofibrosis.
2009
Aims: Essential thrombocythaemia (ET) and primary myelofibrosis (PMF) share some clinical and pathological features, but show different biological behaviour and prognosis. The latest contributions to understanding the nature of these disorders have focused on bone marrow microenvironment remodelling and proliferative stress, recognising megakaryocytes (MKCs) as “key-cells”. The aim of this study was to investigate the apoptotic profile of ET and PMF MKCs in order to further characterise the biology of these disorders. Methods: Bone marrow biopsy samples from 30 patients with ET, and 30 patients with PMF, were immunophenotypically studied for the expression of pro-apoptotic (Fas, Fas-L, Bax,…
Detection of residual leukemic blasts in adult patients with acute T-lymphoblastic leukemia using bone marrow trephine biopsies: comparison of fluore…
2010
Evaluation of remission in adult acute lymphoblastic leukemia (ALL) normally relies on cytologic evaluation and flow-cytometric analysis. The diagnostic impact of bone marrow trephine biopsies has not been studied so far. We investigated 26 biopsies of 16 patients with T-ALL. Double fluorescent immunostaining with TdT and CD3 was performed. Corresponding cytologic evaluation and flow-cytometric data were available. In 17 of 26 investigations, the results were concordant (either positive or negative). In one examination, residual blasts were not recognized by trephine biopsy, but by other methods. By contrast, in eight investigations, the leukemic blasts were found only in the bone marrow tr…
Expression of Matrix-Degrading Cysteine Proteinase Cathepsin K in Cholesteatoma
2001
Cholesteatoma is a nonneoplastic lesion of the middle ear space or mastoid that is histologically characterized by a progressive bone erosion of the ossicles and surrounding bone. Several matrix-degrading enzymes have been implicated as mediators of this bone erosion. Because the novel cysteine proteinase cathepsin K has been shown to play a central role in bone resorption, we examined the expression of this enzyme in tissue specimens of cholesteatoma. Tissue specimens of 9 patients with cholesteatoma were obtained during middle-ear surgery. Expression of cathepsin K mRNA was determined by RT-PCR using specific primers. Immunohistochemical analysis of cathepsin K protein expression in tissu…
Chromophobe cell renal carcinoma and its variants--a report on 32 cases.
1988
This paper reports on 32 chromophobe cell renal carcinomas observed in 697 renal cell cancers (RCC) of adults (peak in the sixth decade of life). The chromophobe cell-type differs from other types of RCC macroscopically, the cut-surface being predominantly of grey-beige colour. Histologically, there are two variants: one is the typical (light) variant (n = 22) and the other is eosinophilic (n = 10). Both variants have in common (a) reaction of the cytoplasm with Hale's acid iron colloid; (b) electron microscopic detection of cytoplasmic microvesicles (150-300 nm), frequently with 'inner vesicles', and (c) low glycogen content in comparison with the clear cell carcinoma. Immunocytochemical i…
Fluorescence Microscopy as a Diagnostic Tool for Dermatophytosis.
2016
Dermatophytosis is a superficial fungal infection of keratinized tissues. Dermatophytes can cause discomfort but are not usually life threatening. However, the infection can spread and may lead to systemic fungal infections in immunocompromised patients. Currently available diagnostic methods include potassium hydroxide (KOH) testing and periodic acid-Schiff (PAS) staining. However, most diagnostic techniques cannot be performed rapidly; days to weeks may be required for conclusive results. Certain dermatophytes autofluoresce and can be observed under fluorescence microscopy. The authors examined a series of 24 cases of hematoxylin and eosin-stained dermatophytoses using fluorescence micros…
The Glomerular Lesions in Endotheliotropic Hemolytic Nephroangiopathy (Hemolytic Uremic Syndrome, Malignant Nephrosclerosis, Post Partal Renal Insuff…
1982
The term "Endotheliotropic Hemolytic Nephroangiopathy" (EHN) comprises various clinically or pathomorphologically defined disease states with severe renal lesions (e.g. hemolytic uremic syndrome, malignant nephrosclerosis, post partum renal insufficiency) which, to date, have been considered as different entities. We attempted to assign accompanying glomerular changes based upon light and electron microscopy to the above mentioned clinical pictures and their various stages. The accordingly classified glomerular lesions (G1--G3 and Ga) are of critical importance in pathohistological differential diagnosis. Since it is assumed that fibrin is a causing event in the pathogenesis of the vascular…
Microvascular injury and repair in acute human bacterial pyelonephritis.
1987
Acute inflammatory cell-capillary endothelial cell interactions, related to injury and repair, were investigated light and electron microscopically in acute human bacterial pyelonephritis. In inflammatory infiltrate-adjacent microvessels, the small capillaries were completely occluded by leukocyte plugs and the large capillaries were densely filled with acute inflammatory cells adhering to the endothelium. Severe damage to small and large capillaries was observed around endothelium adherent, degranulated neutrophil granulocytes containing phagocytosed bacteria. There were spaces in the endothelium, degradation of the vascular basement membrane, of the perivascular interstitial matrix and of…
Hepatitis A-like non-A, non-B hepatitis: light and electron microscopic observations of three cases.
1986
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.