Hexestrol-linked cytotoxic agents: synthesis and binding affinity for estrogen receptors.

With the erythro-hexestrol derivative 2 as the starting material, a variety of cytotoxic linked hexestrol (HEX) compounds were prepared including the HEX-N-lost derivative 36, the HEX-(chloroethyl)nitrosourea 38, the HEX-cyclophosphamide 44, and the HEX-epoxide 68. Relative binding affinity to estradiol receptors were in the magnitude of 1%, similar to that of comparable diethylstilbestrol compounds. HEX derivatives with long polyether spacers (64, 65, 70, 71) showed no significant decrease in binding affinity in contrast to derivatives with other bulky side chains.

[Treatment of the open tibial fracture with the fixateur externe with special reference to osteosynthesis of the fibula]. / Die Behandlung der offenen Unterschenkelfraktur mit dem Fixateur externe unter besonderer Berücksichtigung der Osteosynthese der Fibula.

In the treatment of open fractures of the lower limb and of fractures combined with severe damage of soft tissues, external fixation is favoured. Additional soft tissue damages in the compartments of the lower limb are avoided by using an external fixation in form of a clamp. In defect fractures, shattered fractures and in all fractures in the distal third the stability of clamp fixation is enhanced by plating of the fibula. Furthermore by osteosynthesis the reconstruction of the correct length of the lower limb can be performed. 36 fractures healed definitively in an average of 17.1 weeks by this procedure. Secondary procedures were: 8 cases with decompression of compartments, 11 cancellous bone grafts, 13 fixateur externes were removed because of the infection of the Schanz'screws, and healing was achieved by using a plaster cast. The therapeutical procedure was changed in 5 patients to a plate osteosynthesis and in 8 patients to an intramedullary nail.

[Indications for operation in elbow dislocation]. / Die Indikation zur Operation bei der Ellbogenluxation.

This paper briefly presents the anatomy of the elbow joint, its pathophysiology, the various types of dislocation of the elbow joint and concomitant injuries, the appropriate diagnostic procedures and the indications for surgery and the operative technique applied for correction of dislocation. The only urgent indications for operative treatment are elbow joint dislocation with concomitant bone injuries, persistent instability or luxation position, open injuries and vessel and/or nerve injuries. For purely ligamentous lesions combined with relative loss of stability an operative procedure does not seem necessary. The operative technique applied for the treatment of habitual or recurrent dislocation is also described.

Chitosan-elicited callose synthesis in soybean cells as a ca-dependent process.

A new method for the rapid and quantitative fluorometric determination of callose is described. In suspension-cultured cells of Glycine max, synthesis of callose starts within 20 minutes of treatment with chitosan and parallels over hours the accumulation of 1,3-linked glucose in the wall. Poly-l-lysine also elicits callose synthesis. The effect of chitosan is enhanced by Polymyxin B at low concentrations; this antibiotic alone at higher concentrations can also induce callose synthesis. Callose synthesis is immediately stopped when external Ca(2+) is bound by ethylene glycolbis-(2-aminoethyl ether)-N,N'-tetraacetate or cation exchange beads, and partly recovers upon restoration of 15 micromolar Ca(2+).Callose synthesis is observed only when membrane perturbation causing electrolyte leakage from the cells is induced by one of the above treatments. It does not appear to be due to de novo synthesis or proteolytic activation of 1,3-beta-d-glucan synthase. It is concluded that this Ca(2+)-dependent enzyme is directly activated by the influx of Ca(2+) occurring concomitantly with the leakage of cell constituents. This suggestion is also discussed in conjunction with the chitosan-induced synthesis of phytoalexin in the same cells.

Effect of Chitosan on Membrane Permeability of Suspension-Cultured Glycine max and Phaseolus vulgaris Cells.

Treatment of suspension-cultured Glycine max cv Harosoy 63 cells with soluble chitosan (20-500 micrograms per milliliter) increased membrane permeability as shown by leakage of electrolytes, protein, and UV absorbing material. Severe damage to the cell membrane by chitosan (100 and 500 mug/ml) was also indicated by reduced staining with fluorescein diacetate and the leakage of fluorescein from preloaded cells. Other basic polymers (poly-l-lysine, histone, DEAE-dextran, protamine sulfate, and glycol chitosan) also increased permeability, whereas the basic monomers l-lysine and d-glucosamine, and acidic or neutral polymers were not active. Chitosan-induced leakage was inhibited by divalent cations, the order of effectiveness being Ba(2+) > Ca(2+) > Sr(2+) > Mg(2+). Na polygalacturonate and Na poly-l-aspartate also reduced polycation-induced leakage, probably by formation of polycation-polyanion complexes. A chitosan-polygalacturonate complex precipitated on mixing solutions of the two polymers containing approximately equal numbers of galacturonate and glucosamine residues, but not with either polymer in excess. A similar concentration-dependent precipitation of chitosan by Na poly-l-aspartate was found. Leakage from Phaseolus vulgaris cv Grandessa cells was also induced by chitosan, and was inhibited by Ca(2+) and Na polygalacturonate.

Binding of Ricinus communis agglutinin to the mitochondrial inner membrane as an artifact during preparation.

Endosperm from Ricinus communis was homogenized in the presence of 3H-labelled Ricinus communis agglutinin, with or without addition of lactose. In preparations without the binding-specific sugar the subfraction containing the mitochondrial inner membrane contained sufficient labelled agglutinin to account for the agglutinin reported to be associated with this membrane.