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J J Adnet

Publications and source records attributed to J J Adnet.

At least 37 records · Page 2Linked to original sources
PubMed1991

[Nucleolar organizers in superficial bladder tumors. Prognostic analysis of 37 observations].

Nucleolar Organisers (NORs) are intranucleolar segments of DNA coding for ribosomal RNA. The agyrophilic proteins (AgNOR) associated with NORs allow them to be cytolabelled on paraffin sections. The number of NORs (NOR index) is correlated with cellular proliferation and has a diagnostic and prognostic value in neoplastic disease. The AgNOR method was analysed in a series of 37 superficial bladder tumours with different clinical courses. The NORs were counted in normal urothelium, on superficial tumours used to establish the diagnosis of the disease and on recurrent superficial tumours. The NOR index was 4.54 for normal urothelium, 5.89 for non-invasive superficial tumours, 7.33 for invasive superficial tumours, and 9.75 for invasive recurrences. These results demonstrate an increase in nucleolar argyrophilia with invasion and invasive potential of superficial bladder tumours which were initially homogeneous for stage and grade. The AfNOR method could constitute a new method of early histoprognostic evaluation for urothelial tumours.

Actuarial Analysis↗
PubMed1990

[Nucleolar organizers: NOR. New prognostic factors in prostatic cancer. Preliminary results in 20 cases].

The authors present a preliminary series if two groups of ten patients with advanced prostatic cancer with sufficient follow-up in whom the study of nucleolar organizers (NOR) was performed according to a new light microscopy argentaffin technique. This original technique was developed by D. Ploton at the CHU de Reims. The principles of the technique are presented. The interpretation of the results, very dispersed at the present time, leads the authors two us two new clinical and histological indicators estimating the degree of severity of the prostatic cancer: the index of clinical severity based on the quality of survival and its duration from time T0 and the multifactorial index of histological severity based on the WHO classification, Gleason grade and NOR.

Humans↗
PubMed1988

[Silver staining of nucleolus organizer regions (NORs). Application to the study of nucleolar structure and value in pathology].

Nucleolus is the morphologic expression of synthesis and maturation of ribosomal RNA (rRNA) from amplified ribosomal DNA (rDNA). Nucleolar Organizer Regions (NORs) are functional subunits of the nucleolus in which actively transcribed rDNA is surrounded with numerous regulatory proteins. Some of them are argyrophilic non-histone proteins (Ag-NOR proteins). By using a cytochemical reaction based on this argyrophilia, active NORs may be stained by the precipitation, at their level, of metallic silver granules whose quantity is directly related to the nucleolar activity. In the present paper, we described various applications of a silver-staining method we developed in our laboratory. The Ag-NOR proteins were ultrastructurally localized within precise nucleolar components. Moreover by viewing thick-sections of silver-stained cells with high-voltage microscopes we were able to describe the three-dimensional structure of nucleoli. Finally, this silver-staining method may be applied at the optical level, to sections of routinely fixed and paraffin-embedded human tissues. With this simple staining method, it is now possible to study the relationships of the number of nucleolar argyrophilic structures with the diagnostic of neoplasms.

Humans↗
PubMed1988

[Breast carcinomas and the extracellular matrix].

This paper underlines the interrelations between tumoral cells and the extra-cellular matrix in breast cancers with possible applications for the diagnosis and the prognosis. In mammary carcinomas, the first step of tumoral invasion is characterized by the loss of basement membrane components, particularly type IV collagen and laminin. Immunohistochemical detection of these disruptions of basement membrane is easy and useful for the diagnosis of "in situ" or microinvasive carcinomas. Laminin seems also to facilitate the adhesion of cancer cells to type IV collagen, and the dosage of its fragment P1 in the blood serum may be a good marker for the follow up of the patients. Stromal reaction involves many intricate macromolecules of the extra-cellular matrix. Types I and III collagens are often present in non colloid carcinomas. Rate, turn over of elastin and its prognostic value are still debated. Elastosis is related to well differentiated carcinomas and the presence of estrogen receptors. The stroma of the colloid form of breast cancer is rich in proteoglycans. Malignant and stromal cells, through the intermediary of cytokines, can synthesize these macromolecules. Hyaluronic acid and chondroitin sulfate are abundant in mammary carcinomas and form a favorable substrate for the growth and the migration of malignant cells. However, proteases decrease and limit their action. The presence of fibronectin, principally in the stroma, is difficult to interpret but fibronectin seems to play a role in tumoral retraction.

Basement Membrane↗
PubMed1987

Behaviour of nucleolus during mitosis. A comparative ultrastructural study of various cancerous cell lines using the Ag-NOR staining procedure.

The aim of the present work was to study the distribution and the behaviour of the silver-staining nucleolar organizer region (Ag-NOR) proteins at the ultrastructural level during interphase and mitosis in five human and murine cancerous cell lines each characterized by a typical nucleolar morphology. During interphase the Ag-NOR proteins are restricted to the fibrillar centres (F.C.) and/or to the dense fibrillar component (D.F.C.). During prophase the silver-staining components come into close contact with some chromosomes and are arranged with a typical polarity: chromosome, F.C. and D.F.C. Then F.C. and D.F.C. together form roundish silver-stained structures and integrate in part within indentations at the periphery of the metaphase chromosomes. During anaphase and telophase large and small spherical silver-staining structures may be seen. They correspond respectively to the metaphase NORs and to numerous structures which appear de novo within ribonucleoprotein (RNP) material localized between the chromosomes. During late telophase the number of the small silver-staining structures decreases whereas the size of the larger ones increases. Then the interphase nucleoli recover their typical shape. These results suggest that when rRNA synthesis is impaired during mitosis the inactive NORs assume a structure and a localization which are not typical of the cell line. In contrast the F.C. and D.F.C. are probably two aspects of the NORs whose typical distribution, relative to the other nucleolar components, gives the interphasic nucleolus its characteristic morphology.

Anaphase↗
PubMed1987

Canthaxanthin retinopathy. An investigation by light and electron microscopy and physicochemical analysis.

The eyes of a patient with canthaxanthin retinopathy were obtained at autopsy and examined by light and electron microscopy. Various tissues of one eye were also studied by physicochemical methods. Morphologically, there were red, birefringent, lipid-soluble crystals in the inner layers of the entire retina. They were particularly large and numerous perifoveally, where they were also clinically visible, but they also occurred frequently in a ring-shaped form peripherally and, less frequently, equatorially. The crystals were located in a spongy degeneration of the inner neuropil, where atrophy of the inner parts of the Müller cells was noticed. The compound isolated from the retina was identical with synthetic canthaxanthin according to mass and proton-resonance spectroscopy. Quantitatively, the retina contained up to 42 micrograms canthaxanthin per gram of tissue besides a minor amount of other carotenoids. Of the other tissues of the eye, only the ciliary body contained measurable concentrations of canthaxanthin. From the great number and size of the crystals, on the one hand, and the relatively small amount of isolated canthaxanthin on the other, it was concluded that the crystals presumably represent a canthaxanthin-lipoprotein complex rather than pure canthaxanthin alone. Examination showed that clinically, only the central portion of the canthaxanthin thesaurismosis, where crystals are packed most densely, can be seen.

Aged↗
PubMed1987

The three-dimensional ultrastructure of interphasic and metaphasic nucleolar argyrophilic components studied with high-voltage electron microscopy in thick sections.

The three-dimensional structure of the nucleolar argyrophilic components was studied by recording stereo-pairs of tilted thick sections--0.5-2 microns thick--observed with 200 and 300 kV high-voltage electron microscopy (HVEM). Using a very specific silver staining method, the argyrophilic components were stained with a high contrast relatively to the unstained background, thus allowing their study with a high resolution within thick sections. This study was performed on compact nucleoli (of HL60 and K562 cells), on reticulated nucleoli (of human breast cancerous cells) and on metaphasic nucleolar organizer regions (NORs). In compact nucleoli argyrophilic components show a 'knotted rope-like' structure in which knots are constituted of one central fibrillar centre surrounded at some distance by loops of the dense fibrillar component and in which the rope is constituted of dense fibrillar component. In reticulated nucleoli silver deposits are confined to the surface of the nucleolonema as several strands twisted at the periphery of the fibrillar component. During metaphase some NORs get a characteristic crescent-shaped structure disposed at the periphery of some chromosomes.

Breast Neoplasms↗
PubMed1986

Chromosomal changes in a documented case of malignant histiocytosis: significance of polyploidy.

A case of malignant histiocytosis was studied by cytology, cytochemistry, electron microscopy, and cytogenetics. It was shown that the malignant cells expressed a fully differentiated histiocytic pattern with high macrophagic activity. This correlated with the presence of polyploid metaphases. The significance of polyploid cells in the definition of malignant histiocytosis is discussed.

Aged↗
PubMed1986

Improvement in the staining and in the visualization of the argyrophilic proteins of the nucleolar organizer region at the optical level.

The argyrophilic proteins of the nucleolar organizer region (Ag-NOR proteins) were specifically localized at the optical level with a modified one-step silver technique performed at 20 degrees C. This method was applied to various materials including cells in smears, chromosomes, semi-thin sections of plastic-embedded cells and sections of paraffin-embedded human pathological tissues. In order to improve the visualization of the silver deposits we tested various modes of imaging, including bright-field, Nomarski contrast, reflected light and combined Nomarski contrast with reflected light. The use of Nomarski contrast is useful to define precisely the phases of mitosis. The use of reflected light, which is based on the ability of silver to reflect incident light specifically, gives images with an improved resolution compared to bright-field.

Cell Line↗
PubMed1986

[Anaplastic small-cell bronchial carcinoma of the composite type].

The authors report an anatomico-clinical case (with ultrastructural study) of bronchial anaplastic carcinoma with composite, triple differentiation oat-cell subtype. The patient underwent early surgical excision followed by radiotherapy and chemotherapy. With the help of data from the literature concerning this composite subtype which suggests new theories on the histogenesis of bronchial cancer, the authors emphasize the value of surgical treatment for this unusual subtype of anaplastic carcinoma.

Aged↗
PubMed1986

Recurrent deletion of the short arm of chromosome 3 in human renal cell carcinoma: shift of the c-raf 1 locus.

A cytogenetic study performed on 6 human renal cell carcinomas after short-term culture on extracellular matrix with serum-free medium showed aneuploidy without structural changes in 2 tumors and a rearrangement of the short arm of chromosome 3 in 4 tumors, including deletions and a translocation involving the 3p14 and 3p21 bands. Chromosomal in situ hybridization with a c-raf 1 probe demonstrated that in 2 renal cancers with del3(p14 or 21) the cellular oncogene had shifted from 3p25 to 3p14 as a result of an interstitial deletion.

Carcinoma, Renal Cell↗