[The indications for surgical treatment in venous malformations of the lower extremities]. / Indicatiile tratamentului chirurgical în malformatiile venoase ale membrelor inferioare.

The venous congenital anomalies are diseases with a low frequency to compare with the great number of the acquired venous diseases, but that present interest specially through their disabled evolution and through the insufficient standardisation and limited treatment. The paper present the experience of the First Surgical Clinic of Timisoara, with 76 venous congenital abnormalities of the lower limbs. We studied 48 patients with syndrome Klippel-Trénaunay, 12 with syndrome Parkes Weber and 16 venous hemangiomas. The surgical treatment was performed to 6 patients with syndrome Klippel-Trénaunay; in 3 cases we have do phlebolysis. The operation realized in syndrome Parkes Weber was in 1 patient the Malan operation and in another one an embolisation. 13 patients with venous hemangioma were operated on (81%) performing in 12 cases the complete excision and in 1 case the transcutaneous ligature followed by sclerotherapy. The indications of the surgical treatment in the venous congenital abnormalities require a good judgment, a precise lesion diagnosis and a competent evaluation of the therapeutics venous.

Calmodulin-dependent Ca2+-pump ATPase of human smooth muscle sarcolemma.

An enzymatically active Ca2+-stimulated ATPase has been isolated from the sarcolemmal sheets of human smooth muscle (myometrium). Ca2+-ATPase activity was quantitated in an assay medium which simulated the characteristic free ionic concentrations of the cytosol. New computer programs for calculating the composition of solutions containing metals (Ca, Mg, Na, K) and ligands (EGTA, ATP), based on the updated stability constants, were used. In detergent-soluble form the enzyme has a high Ca2+-affinity expressed by an apparent Km (Ca2+) of 0.25 +/- 0.04 microM. The maximum specific activity (about 20 nmol of Pi/mg protein/min) was found in the micromolar domain of free-Ca2+ concentrations, the same levels required for normal maximal contractions in smooth muscle. The variation of free-Ca2+ concentration in the assay medium over 4 orders of magnitude (pCa 9 to pCa 5) resulted in a sigmoidal dependence of enzymatic activity, with a Hill coefficient of 1.4, which suggested the regulation of Ca2+-ATPase by allosteric effectors. The presence and the activator role of endogenous calmodulin in smooth muscle sarcolemma was proved by calmodulin-depletion experiments and by using suitable anticalmodulinic concentrations of trifluoperazine. The addition of exogenous calmodulin restored the enzyme activity. Apparently, the concentration of calmodulin in isolated smooth muscle sarcolemma is about 0.1% of sarcolemmal proteins, as deduced from the comparison of calmodulin-depletion and calmodulin-readdition experiments. Calmodulin increased significantly the enzyme Ca2+-affinity and Vmax (by a factor of about 10). At variance with the sarcoplasmic reticulum Ca2+-ATPase, the sarcolemmal Ca2+-ATPase is extremely sensitive to orthovanadate, half-maximal inhibition being observed at 0.8 microM vanadate. In conclusion, the Ca2+-ATPase isolated from smooth muscle sarcolemma appears very similar to the well-known Ca2+-pump ATPases of erythrocyte membrane, heart sarcolemma or axolemma. We suggest that this high-affinity Ca2+-ATPase represents the calmodulin-regulated Ca2+-extrusion pump of the smooth muscle sarcolemma.

[Causes of failure in surgical arteriovenous anastomoses]. / Cauzele de esec în anastomozele arteriovenoase terapeutice.

The causes of failure in surgical arteriovenous anastomoses are discussed with reference to 60 operations performed on 52 patients suffering from chronic renal insufficiency in the uremic stage. The various technical variants applied are shown, as well as the early and late complications and the order in which reinterventions were performed. The work concludes with an original mathematical study of the blood output in the three fistula variants practiced by the authors, designed to supply evidence of their functional value.