Antithrombin III Avranches, a new variant with defective serine-protease inhibition--comparison with antithrombin III Charleville.

A decreased plasma antithrombin activity in presence or in absence of heparin was discovered in a 47-year-old patient presenting with recurrent venous thromboembolism. The immunoreactive material (AT III-IR) was normal. The same biological abnormalities were found in two relatives of the patient, leading to the diagnosis of hereditary qualitative AT III deficiency. The propositus' AT III was coeluted with normal AT III from an heparin-sepharose column. An additional step of ion-exchange chromatography on a Mono Q column using a FPLC system (Pharmacia, St-Quentin en Yvelines, France) allowed the purification of a protein which was homogenous in SDS-10% polyacrylamide electrophoresis gel (PAGE). AT III purified from propositus' plasma, normal plasma and the plasma of the patient known to have an AT III variant with defective protease binding (AT III Charleville) were compared. The specific activities measured as heparin cofactor antithrombin or factor Xa inhibition in absence of heparin were decreased to half the normal value. Kinetic studies confirmed a decreased rate of thrombin inhibition for both abnormal AT III preparations. SDS-PAGE experiments performed in purified system and immunoblots obtained from plasma showed that the two variants have different behaviour: in the case of AT III Charleville thrombin induced an apparent 5 k delta increase in molecular mass, probably due to a conformational change. AT III Avranches did not form stoechiometric complexes with thrombin, but was unmodified by the protease.

[Lipids and lipoproteins in atherosclerotic arteriopathy of the legs. Unusual study of very low density lipoproteins]. / Lipides et lipoprotéines dans l'artériopathie athéroscléreuse des membres inférieurs. Etude particulière des lipoprotéines de très faible densité.

Lipids, apolipoproteins A1 and B and lipoproteins were studied in 49 patients with peripheral arterial disease and in 26 control patients. The observed hypertriglyceridemia was related to the elevation of the VLDL lipid mass; no alteration in their structure could be shown. The origin of this VLDL excess was discussed especially the role of tobacco and genetic.

[Subungual glomus tumor. Apropos of a case]. / Tumeur glomique sous-unguéale. A propos d'un cas.

Glomus tumors are rare, though not exceptional. They are considered by some authors as hyperplasia of a normal neuromyo-arterial glomus, by others as a benign tumoral proliferation. Most of them combine the three histological types initially described by Masson. i.e. solid, angiomatous and muco-hyaline. Subungual glomus tumors are more often seen in middle-aged subjects than in children. Although often belatedly diagnosed, they have characteristic symptoms, notably paroxysmal, acute pain provoked by cold or by minimal traumas: the Raynaud's phenomenon is inconstant and localized to the tip of the affected finger. When clinical and standard radiological examinations are normal, arteriography may be useful to confirm the diagnosis and locate the lesion. The main differential diagnoses before arteriography are post-traumatic neuroma and subungual melanoma. Surgical treatment is straightforward, but pain may recur post-operatively; it may be due to incomplete excision, development of a new tumor, presence of other tumors or cicatricial neuroma.

[Value of arteriography in the exploration of subungual glomus tumors. Apropos of a case]. / Intérêt de l'artériographie dans l'exploration des tumeurs glomiques sous-unguéales. A propos d'un cas.

Difficulties in the diagnosis of subungual glomus tumors are increased when clinical examination and standard radiographic images are normal. In these cases arteriography is a useful procedure, opacification in the arterial phase of a small vascular lake confirming the diagnosis and localizing the lesion. A case is described that illustrates the interest of this examination, although it is indispensable only in patients with glomus tumors of atypical clinical expression or when symptoms recur after excision.