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F Gudat

Publications and source records attributed to F Gudat.

At least 91 records · Page 5Linked to original sources
PubMed1992

Extranodal multilobated B-cell lymphoma: diagnosis by fine needle aspiration.

Malignant lymphoma with multilobated nuclei is a rare variant of follicle centre cell lymphoma. We describe a 34-year-old patient who initially presented with enlarged cervical and inguinal lymph nodes due to a histologically proven centroblastic-centrocytic lymphoma. Two years later, she developed a soft tissue mass in the gluteal area and malignant lymphoma with multilobated nuclei was diagnosed on fine needle aspiration.

Adult↗
PubMed1992

Renal graft rejection or cyclosporin toxicity? Early diagnosis by a combination of Papanicolaou and immunocytochemical staining of urinary cytology specimens.

A method is described for distinguishing between graft rejection and cyclosporin nephrotoxicity in renal allograft recipients by analyzing fresh morning urine samples. The technique combines classic Papanicolaou with immunocytochemical staining and was performed in urine specimens from a series of 42 patients. Early-stage cyclosporin toxicity was usually associated with increased numbers of proximal tubular cells only, whereas in rejection and late-stage toxicity there were increases in both tubular cells and in lymphocytes and monocytes (greater than 2000 cells/ml urine). Differentiation between these two clinical conditions was achieved by immunostaining, which revealed that increased numbers of CD25+ and CD8+ cells, as well as an increase in the HLA-DR/Lu5 ratio, were typical of rejection. CD25 positivity proved to be the best indicator of rejection, with a sensitivity and specificity of more than 90%. A cytodiagnostic algorithm is presented that is based on cell numbers and types, including immunophenotypes. The proposed method has the advantage of being noninvasive and appears to represent a reliable and rapid adjunct for the monitoring of graft function, especially in high-risk patients on cyclosporin immunosuppression.

Adolescent↗
PubMed1992

Studies on morphological outcome of cyclosporine-associated arteriolopathy after discontinuation of cyclosporine in renal allografts.

Cyclosporine (CSA)-associated arteriolopathy (CAA) is the second most frequent morphological diagnosis in renal allografts and its final outcome remains unclear. The present study was performed to clarify the morphological outcome of CAA by follow-up histological analysis after stopping CSA. Furthermore, the clinical management of patients showing CAA is discussed. Most of the patients came from our early experience with CSA between 1981-1983 when CSA doses and trough levels were high. Twenty recipients were divided into two groups according to the presence of CAA after stopping CSA: group A (n = 9) showed persistent CAA and group B (n = 11) showed no CAA. The majority of the patients, including five incomplete remission in group A, showed obvious improvement of CAA even if the arterioles were severely affected. Improvement of CAA was noted a few months after stopping CSA or after lower dose CSA therapy. There were no significant differences in CSA blood levels or duration of CSA therapy between the groups. The severity of preexistent CAA was significantly greater in group A. Only two patients who died from malignant tumor showed exacerbation of CAA. Eight patients died and eight grafts were lost, seven due to vascular rejection and one to hemolytic uremic syndrome-like CAA. Poor renal function was also noted in four cases with functioning graft owing to vascular rejection even though the improvement of CAA was evident. The complete regression of CAA and the remodelling of arterioles showing well preserved vascular patency were frequently found after stopping or reducing the dose of CSA.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Cardiac myxomas: immunohistochemical study of benign and malignant variants.

Immunohistochemical investigation of 11 cardiac myxomas (CMs) including one malignant metastasizing CM showed a co-expression of epithelial (lu-5 and CAM 5.2), mesenchymal (vimentin) and neuroendocrine antigens (neuron-specific enolase) in all tumour cells. Factor VIII was found in the endothelial cells of capillaries only. In the subendocardium of fetal heart tissue close to the foramen ovale myofibroblasts reacting with the panepithelial antibody lu-5 were detected. We conclude that CMs are neoplasms that may develop from embryonic cell remnants.

Adult↗
PubMed1991

Collagen type III glomerulopathy: a new idiopathic glomerular disease.

A new type of idiopathic glomerular disease is reported in a 49-year-old Italian woman who presented with uncharacteristic renal symptoms, i.e., hypertension and slight proteinuria. Clinical investigation excluded a familial renal disease and more specifically nail-patella syndrome. Diagnostic renal biopsy by light microscopy showed a picture similar to membranoproliferative glomerulonephritis. The enlarged glomeruli were lobulated, the peripheral basement membranes were thickened by the deposition of light-microscopically undefined material, cell proliferation was lacking. By electron microscopy, the material was nonhomogenous, partly granular partly fibrillar, containing typical collagen fibers. The latter were identified as collagen type III, to a lesser extent collagen type I. Review of the literature resulted in 12 similar or identical cases reported from Japan and one additional case reported in a white American female. Evidence of systemic disease is lacking. Etiology and pathogenesis are elusive. A progressive deterioration of renal function must be expected. Collagen type III glomerulopathy is suggested as term of this new type of idiopathic glomerular disease.

Biopsy↗
PubMed1991

Tumor necrosis factor receptors in lymphoid tissues and lymphomas. Source and site of action of tumor necrosis factor alpha.

Tumor necrosis factor alpha (TNF alpha), which is produced by germinal center dendritic reticulum cells (DRC) in lymphoid tissue, plays a regulatory role in a local immune response. However no information is available on the nature and location of cells responding to this cytokine. Thus TNF receptor distribution was investigated in situ by immunohistochemistry using monoclonal antibodies directed against the p75 and p55 receptor proteins. Receptor expression was unique and restricted to the lymphoreticular tissue. The p75 receptor was found on activated lymphocytes and interdigitating reticulum cells of the T-cell area, whereas the p55 receptor was confined to the germinal center DRCs, which are the main site of TNF alpha production. The two receptor proteins were expressed on distinct cell populations of the lymphoid system and no coexpression was observed. Preliminary results indicate that TNF receptor (TNFR) expression is regulated; Upregulation of TNFR proteins was found in reactive hyperplasia together with increased TNF alpha expression. In lymphoproliferative disorders, expression of the p75 receptor and TNF alpha was found mainly in high-grade malignant non-Hodgkin lymphomas. In summary, TNF alpha produced by germinal center DRCs might regulate an in vivo immune response through autocrine and paracrine pathways. Thus TNF alpha might signal, through the distinct TNFR proteins, the p55 and p75 receptor, which are expressed on different cell types in lymphoid tissue.

Humans↗
PubMed1991

Tumour necrosis factor receptor distribution in human lymphoid tissue.

The nature and location of cells responding to tumour necrosis factor-alpha (TNF-alpha) were investigated in situ by immunohistochemistry using monoclonal antibodies (mAb) directed against the p75 and p55 proteins of the TNF receptor. Receptor expression was found in the thymus and secondary lymphoid tissues. In the thymus the p75 receptor was confined to medullary lymphoblasts and dendritic cells, which co-stain with the Tac protein of the interleukin-2 (IL-2) receptor. In lymph nodes and other secondary lymphoid tissues, the p75 receptor was expressed on activated lymphocytes and interdigitating reticulum cells of the T-cell area, whereas the p55 receptor was confined to the germinal centre dendritic reticulum cells (DRC), which is the main site of TNF-alpha production. TNF receptor (TNFR) proteins were up-regulated in reactive hyperplasia together with increased TNF-alpha expression. Surprisingly, no TNFR was detectable on non-lymphoid tissues. The species specificity of these TNFR antibodies was high: whereas the antibodies cross-reacted with epitopes in non-human primates, no immunoreactivity was detected in lower animal species, e.g. dog, rabbit and rodents. The data presented suggest that TNF-alpha, which is produced by germinal centre DRC, might regulate an in vivo immune response through autocrine and paracrine pathways, e.g. through the p55 and p75 receptor proteins, which are expressed at different sites of the lymphoid tissue.

Animals↗
PubMed1991

Immunohistochemical studies on human pituitary gland and adenomas.

To study coexpression patterns in normal and adenomatous pituitaries, frozen (n = 4) and paraffin-embedded (n = 10), normal human glands and 34 pituitary adenomas were investigated, using immunoperoxidase and double-labeling immunofluorescence methods. Broad range monoclonal antibodies (mAB) against cytokeratins (CK) (lu-5, A45-B/B3, AE1/3, CAM 5.2) as well as anti-CK18 (DC10) and anti CK19 (A53-B/A2) were compared with mAB's against vimentin, epithelial membrane antigen (EMA), epithelial sialomucin (ESM 140 C1), GFAP (GF-2), neurofilament (2F11), Leu-7 (HNK-1) and polyclonal AB's against pituitary hormones (ACTH, FSH, LH, TSH, GH, PRL). CK and vimentin coexpressing endocrine cells, mainly of the ACTH type, were observed in the pars intermedia in 5 of 14 normal pituitaries. All hormone producing cells expressed CK. The mAB A53-B/A2 (CK19) stained selectively the folliculo-stellate cells in frozen and paraffin sections. EMA, sialomucin and Leu-7 antigen localized to different structures of normal pituitaries. 25 of 34 pituitary adenomas exhibited CK positive tumor cells. Coexpression of vimentin or neurofilament protein was rare (2 cases of each). 9 CK negative adenomas were also negative for other intermediate filament proteins. 6 hormone producing adenomas showed unusual positivity for CK19. Whereas EMA and sialomucin reactivity disappeared in adenoma tissues, an enhanced Leu-7 antigen expression in the GH and prolactin adenoma group was noted. The heterogeneity of antigen expression seen in normal and neoplastic pituitary cells calls for further functional studies and usage of a broad range of mAB's against intermediate filaments in immunohistochemical studies of the pituitary.

Adenoma↗
PubMed1990

Measurement of human nerve growth factor binding sites in brain and in peripheral tissues by a specific immunoprecipitation assay.

Using a monoclonal antibody against the human nerve growth factor (NGF) receptor (20.4 IgG), a specific immunoprecipitation assay for the quantitation of human NGF binding sites has been established. The procedure involves specific labeling of NGF receptors by covalent crosslinking to 125I-NGF with a carbodiimide reagent, and subsequent immunoprecipitation of the detergent-extracted 125I-NGF-receptor complexes with the 20.4 IgG. This two-site assay provides a specific method to measure NGF binding sites in peripheral tissues and central nervous system. Moreover, it allows analysis of the immunoprecipitated receptor species by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The finding that specific NGF binding sites are expressed on human neuronal and nonneuronal tissues, including lymphoid tissues, indicates that NGF exerts a broader physiological function than originally ascribed.

Aged↗
PubMed1989

Endogenous megakaryocyte colonies from peripheral blood in precursor cell cultures of patients with myeloproliferative disorders.

Megakaryocyte colony formation, as identified by conventional techniques, was observed in precursor cell cultures from peripheral blood in 8 of 20 consecutive patients with diagnosis of myeloproliferative disease (4/11 patients with polycythemia vera, 3/5 with essential thrombocythemia, 1/2 with primary osteomyelofibrosis and 2 with a myeloproliferative syndrome not further assessable), but not in 50 healthy controls (p less than 0.0001). 7 cultures showed spontaneous erythroid colonies, but were negative for megakaryocyte colonies. Megakaryocyte colony formation was independent of added erythropoietin, plasma or human leukocyte-conditioned medium, but was dependent on the presence of accessory cells. The cells in megakaryocyte colonies had the characteristic morphology of megakaryocytes and stained positively with the IIIa/IIb monoclonal anti-platelet antibody. Thus, megakaryocyte colony formation by precursor cells from peripheral blood in the absence of exogenous stimulating factors seems to be a phenomenon specific for myeloproliferative disease. Differential diagnosis of thrombocythemia may be facilitated by demonstration of endogenous megakaryocyte colony formation, which does not occur in secondary disease.

Cell Nucleus↗
PubMed1989

[Interstitial and glomerular changes in kidney transplants].

This review gives a survey of the most important tubulo-interstitial and glomerular lesions in kidney transplants. Among the tubulo-interstitial lesions subcapsular interstitial fibrosis, acute tubular necrosis, cellular tubulo-interstitial rejection and Ciclosporin associated lesions are briefly described. The review of the glomerular lesions is focused upon intraglomerular coagulation, transplant glomerulitis and transplant glomerulopathy. Among the immunocomplex diseases the preexisting glomerular lesions are stressed. Furthermore the differential diagnosis between rejection associated glomerular lesions and glomerulonephritis is discussed. Finally the prognostic significance of the different morphologic lesions is outlined based on an analysis of 500 biopsies from Basel.

Antigens, CD↗
PubMed1989

[Eccrine hidrocystoma].

Most eccrine hidrocystomas are solitary, asymptomatic lesions. Multiple hidrocystomas are very rare and are probably caused by dilatation of eccrine ducts. Immunohistochemical investigations are helpful in distinguishing whether a solitary or multiple form is present. An isolated hidrocystoma can be treated by surgery or electrocautery. Multiple eccrine hidrocystomas are more difficult to treat. Topical atropine may be successful for multiple lesions. We observed a patient with more than 100 lesions associated with significant hyperhidrosis. Although several systemic drugs were used, no relief of the hyperhidrosis could be achieved. During topical administration of atropine some shrinkage of cysts was seen.

Administration, Topical↗
PubMed1988

The immunohistochemical reactivity of a new anti-epithelial monoclonal antibody (MAb b-12) against breast carcinoma and other normal and neoplastic human tissues.

A mouse monoclonal antibody, MAb b-12, has been described previously (Stähli et al. 1985) which reacts with a Mr 350 kD glycoprotein with mucin-like characteristics (Stähli et al. 1987) expressed in cytoplasm and on the surface of human breast carcinoma cell lines (MCF-7 and ZR-75-1). In the present report the immunohistochemical reactivity of this MAb with normal and malignant human tissues is analyzed. Pre-experiments showed that the epitope b-12 is resistant to formalin treatment allowing the use of tissue processed by standard paraffin embedding methods. 167 normal and 408 neoplastic tissues were tested by indirect immunofluorescence or the avidin-biotin complex method. MAb b-12 stained the apical cytoplasm of secretory epithelia and their secretions including the acinar and ductular epithelia of the breast. It reacted with all breast carcinomas independent of their histological type or stage, frequently with all but in some cases with a fraction of the tumour cells. Some other carcinomas, primarily those of adenomatous differentiation, were also reactive. In these, however, the fraction of positive tumour cells was usually lower. The b-12 epitope is thus a marker for normal and neoplastic epithelia with secretory functions, particularly for breast carcinomas of all histological types and stages, and perhaps a differentiation marker for abortive adenomatous differentiation in solid carcinomas of the gastro-intestinal, uro-genital or respiratory tract.

Antibodies, Monoclonal↗