Search PubMed⌕ Search

Biomedical subjects

A Volant

Publications and source records attributed to A Volant.

At least 55 records · Page 3Linked to original sources
PubMed1989

[Primary malignant melanoma of the bladder. Apropos of a case].

The authors report about a case of a primitive melanoma of the bladder that a man aged 77 years suffered of. The diagnosis was carried-out with certain difficulty on fragments of endoscopic resection and was discussed from the clinical facts as well as from the anatomo-pathological results and, more particularly, from the immuno-histochemical results. This study makes it possible that a comparison be made with those rare cases observed on a world-scale basis which are described in the literature. As far as the bladder is concerned, it constitutes also an attempt of histogenetic explanation of this kind of tumor.

Aged↗
PubMed1988

[A trial use of lenses of human placental collagen in epikeratoplasty procedures].

Epikeratoplasty is a refractive surgery procedure described by Werblin and Kaufman which is simple, effective and reversible. However its development is hampered by the need of human corneas. We evaluated this procedure in rabbits and monkeys using lenticules of human collagen. The collagen is obtained from frozen human placentas, washed and subjected to pepsin digestion; it is contained in the supernatant of centrifugation and can be isolated by a physico-chemical treatment. 15 days after surgery the lenses of 14 rabbits were completely covered with a layer of epithelial cells. 6 months after surgery, the eyes of 14 monkeys were quiet and the lenses were covered with an epithelium made up of 2 to 5 layers of cells. The lens exhibited no inflammatory infiltration and there was no inflammatory reaction around the lens. These studies are still preliminary and longer term tests are necessary. These initial results are very encouraging, prompting us to develop the use of this type of material in refractive surgery.

Animals↗
PubMed1988

[Histological study of 4 lenses from epikeratoplasty. Anatomo-clinical correlation].

Four removed kerato-lens lenticles (1 for keratoconus, 1 for aphakia, and 2 for myopia) have been studied histologically. The reasons for removal of the lenticles were poor visual acuity in spite of a satisfactory anatomic result in three cases and epithelialization of the interface in one case. The epithelium presented modifications, particularly with exoserosis of basal cells and irregularities of thickness. The Bowman membrane was irregular and interrupted in some parts. The corneal stroma had few cells; the keratocytes were observed in the periphery of the lenticle and near the interface.

Adult↗
PubMed1988

[Scanning microscopy comparison of keratotomies using a diamond or steel knife].

We have compared on 4 cadaver eyes the aspect of keratotomies obtained with a diamond blade or a steel blade. We used the scanning electron microscope for the comparison. The incisions with diamond blade are much thinner than the incisions with steel blade. However the steel blade produced regular and smooth keratotomies. Whatever the blades, the microscopic appearance of the penetration was much better than the exit. The choice between cutting instruments for keratotomy depends upon these results and financial factors.

Humans↗
PubMed1987

[Adenocarcinoma of the duodenum. Apropos of 2 cases: review of the literature].

The authors report two cases of duodenal adenocarcinoma. Review of literature has permitted them to conclude the rarity of the lesion which among malignant tumours of the small intestine, is the gommenest. Localization of the tumour in the periampullary area in 47% of cases rendered it difficult to differentiate from ampullary and pancreatic tumours especially with the unknown etiological factors (with exception to villous tumours which has a 35% rate of malignant transformation), and also with unspecific symptoms. Diagnosis by x-ray and endoscopy has an accuracy rate of more then 85%. Prognosis is bad and depend mainly on histological differentiation and lymph node spread. 5 years survival rate of 40-50% can be achieved by curative surgery namely cephalic duodeno-pancreatectomy in cases with no lymph node involvement.

Adenocarcinoma↗
PubMed1987

Acute synovial fluid eosinophilia associated with delayed pressure urticaria: a role for mast cells?

We report a case of exercise induced joint effusion with synovial fluid (SF) eosinophilia of 9,540/mm3 in a patient with delayed pressure urticaria. The SF eosinophilia was an acute but transient event associated with some evidence of local complement activation. Histologic assessment revealed a normal synovial membrane but with no detectable intact mast cells. These observations suggest that mast cells and eosinophils acting in concert can cause joint inflammation.

Acute Disease↗
PubMed1986

Constrictive perivenous mesh prosthesis for preservation of vein integrity. Experimental results and application for coronary bypass grafting.

Saphenous veins undergo dramatic morphologic changes when used as coronary bypass grafts, and careful preparation of the graft alone is inadequate in preventing these changes. In this study, the use of a constrictive mesh for vein graft was evaluated. Fourteen sheep were subjected to a 5 cm resection of the carotid artery. Six sheep (Group A) received a jugular vein interposition graft, and the other eight sheep (Group B) received a jugular vein graft on which the constrictive mesh had been applied. The diameter of grafts in Group A was 14 +/- 1 mm compared with 7 +/- 0.5 mm for Group B (p = 0.05). The animals were put to death 4 months later. Scanning electron microscopy showed a disruption of the endothelial lining in Group A and a normal endothelium in Group B. Microscopy showed a statistical difference between Groups A and B regarding regularity and thickness of the intimal hyperplasia. Group B showed a moderate and regular intimal thickening and increased vasa vasorum. This indicates that distention and subsequent damage of the vein graft may be minimized by use of a constrictive mesh. Saphenous grafts surrounded by this constrictive mesh were inserted in four patients. Vein diameters were, respectively, 5, 4.3, 3.5, and 3.5 mm before meshing. After insertion in the mesh, vein diameters were 4.3, 3.5, 2.8, and 2.5 mm, respectively. Angiography performed 2 months later showed patent grafts of regular caliber.

Animals↗
PubMed1985

[Ultrastructural study of a case of Miescher-Leder granulomatosis disciformis chronica et progressiva].

Ultrastructural study of a case of granulomatosis disciformis occurring on the legs of a 62-year-old woman. The diagnosis is based upon the contrast between the clinical aspect of necrobiosis lipoidica and the histologic aspect of inflammatory granulomatous infiltrate of dermis without necrobiosis nor palisading. Electron microscopic findings are: perivascular mixed cell infiltrate and histiocytic granuloma with lysosomial and phagocytic activity; degenerative and necrotic cellular alterations; modifications of collagen fibres with two types of fibres: the thinnest are the most numerous and have a mean diameter of 50 nm, the thickest of 110 nm; no significant lesions of capillary walls. These findings suggest the following succession of pathological events: cellular necrosis, lysosomial and phagocytic activity, scarring. Some descriptions of necrobiosis lipoidica and granuloma annulare seem to be quite similar and our findings are in favour of the unity of these three illnesses.

Capillaries↗
PubMed1984

[Trifluorothymidine therapy of corticoid-treated herpetic keratitis: experimental study in the rabbit].

The combination therapy of corticosteroids and antiviral agent is often necessary in the treatment of different forms of ocular herpes. The association of superficial ulceration with severe stromal inflammation indicates the possible use of ths therapy. An experimental study was performed in rabbits to evaluate if Trifluorothymidine (TFT) used in combination with topical corticosteroids can heal herpetic superficial ulcerations. Biomicroscopic and histopathologic lesions were compared with those of herpetic control eyes, TFT treated eyes and corticosteroid treated eyes. TFT plus corticosteroid treated lesions showed a clinically favourable evolution comparable to that of TFT treated rabbits without corticosteroid. However anatomopathologic examination revealed stromal alterations with herpetic capsids in keratocytes.

Administration, Topical↗
PubMed1984

[First contact between blood and the arterial prosthesis. Study of the retention of the blood elements].

In order to characterize the nature of the interaction between arterial prostheses and their initial contact with blood, we propose the use of an in vitro test using labelled platelets and fibrinogen to measure the amount of the thrombotic matrix that is entrapped by the wall of the graft. The results have been confirmed by scanning electron microscopy. Polyester prostheses, whose healing process depends on the reorganisation of the thrombotic matrix, retains considerably more blood cells than the polytetrafluoroethylene microporous prostheses or the treated biological devices, whose fate, following implantation, maintains almost complete passivity.

Biocompatible Materials↗