Rekonstruktion des Au?enbandapparats mittels Kniebeugesehnentransplantat bei chronischer Au?enbandinstabilit?t des OSG

Objective

Reconstruction of the anterior talofibular (ATFL) and calcaneofibular (CFL) ligament in patients with chronic lateral ankle instability.

Indications

Symptomatic chronic lateral ankle instability.

Contraindications

Bony malalignment, advanced arthritic changes of the ankle joint, diabetic foot syndrome.

Surgical technique

Reconstruction of the ATFL and CFL with a free gracilisor or semitendinosus tendon graft through a V-shaped tunnel at the insertion site of the ATFL on the talar neck as well as a transfibular tunnel directed anterior to posterior through the fibula tip to a blind ending tunnel in the calcaneus at the insertion site of the CFL. Insertion of the graft through the talar tunnel, passing both graft ends through the fibular tunnel to the calcaneus. Fixation with a bioabsorbable screw.

Postoperative management

Short leg cast for 10?C14?days and partial weight-bearing. Afterwards ankle brace for 6?weeks and functional physical therapy.

Results

From December 2003 to August 2005, reconstruction of the ATFL and CFL with a hamstring tendon autograft was performed in 20 patients with chronic lateral instability of the ankle joint. All patients were evaluated after a mean follow-up time of 1.8?years (15?C36?months). Clinical evaluation referred to the AOFAS score. Stress radiography was performed for objective assessment of lateral ankle stability. Postoperatively 19 of 20 patients reported good subjective stability with no further ankle sprains. The mean postoperative AOFAS score was 92 of 100 points (72?C100). Stress radiography showed a significant reduction of both lateral ankle instability and talar tilt.     

Combination protocols of cytokine therapy with interleukin-3 and granulocyte-macrophage colony-stimulating factor in a primate model of radiation-induced marrow aplasia

Single cytokine therapy with granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin-3 (IL-3) has been shown to be effective in decreasing the respective periods of neutropenia and thrombocytopenia following radiation- or drug-induced marrow aplasia. The combined administration of IL-3 and GM-CSF in normal primates suggested that a sequential protocol of IL-3 followed by GM-CSF would be more effective than that of GM-CSF alone in producing neutrophils (PMN). We investigated the therapeutic efficacy of two combination protocols, the sequential and coadministration of recombinant human IL- 3 and GM-CSF relative to respective single cytokine therapy, and delayed GM-CSF administration in sublethally irradiated rhesus monkeys. Monkeys irradiated with 450 cGy (mixed fission neutron:gamma radiation) received either IL-3, GM-CSF, human serum albumin (HSA), or IL-3 coadministered with GM-CSF for days 1 through 21 consecutively postexposure, or IL-3 or HSA for days 1 through 7 followed by GM-CSF for days 7 through 21. All cytokines and HSA were injected subcutaneously at a total dose of 25 micrograms/kg/d, divided twice daily. Complete blood counts (CBC) and platelet (PLT) counts were monitored over 60 days postirradiation. The respiratory burst activity of the PMN was assessed flow cytometrically, by measuring hydrogen peroxide (H2O2) production. Coadministration of IL-3 and GM-CSF reduced the average 16-day period of neutropenia and antibiotic support in the control animals to 6 days (P = .006). Similarly, the average 10-day period of severe thrombocytopenia, which necessitated PLT transfusion in the control animals, was reduced to 3 days when IL-3 and GM-CSF were coadministered (P = .004). The sequential administration of IL-3 followed by GM-CSF had no greater effect on PMN production than GM-CSF alone and was less effective than IL-3 alone in reducing thrombocytopenia. PMN function was enhanced in all cytokine-treated animals.     

Protein C activators from snake venoms and their diagnostic use

Proteinases converting the zymogen protein C (PC) of vertebrates into activated PC have been detected in several snake venoms. Most PC activators have been purified from venom of snake species belonging to the genera of the Agkistrodon complex. Unlike the physiological, thrombin-catalyzed PC activation reaction which requires thrombomodulin as a cofactor, most snake venom activators directly convert the zymogen PC into the catalytically active form which can easily be determined by means of coagulation or chromogenic substrate techniques. Due to this feature, the fast-acting PC activator Protac from Agkistrodon contortrix contortrix (southern copperhead snake) venom has found a broad application in diagnostic practice for the determination of disorders in the PC pathway. Recently, screening assays for the PC pathway have been introduced, based on the observation that the PC pathway is probably the most important physiological barrier against thrombosis.     

Improved hematopoiesis in anemic Sl/Sld mice by splenectomy and therapeutic transplantation of a hematopoietic microenvironment

The ability of a clonal hematopoiesis-supportive bone-marrow stromal cell line GBlneor to engraft and alter the microenvironment-induced anemia of Sl/Sld mice was studied. Prior to stromal cell transplantation, Sl/Sld mice received 1 Gy total body irradiation (TBI) and 13 Gy to the right hind limb. Two months after intravenous (IV) injection of 5 x 10(5) GBlneor cells, 54.4% +/- 17.0% donor origin (G418r) colony-forming cells were recovered from the right hind limb of Sl/Sld mice. Long-term bone marrow cultures (LTBMCs) established from GBlneor-transplanted mice produced 189.5 CFU-GEMM-forming progenitors/flask over 10 weeks compared with 52.7 +/- 6.2 CFU-GEMM forming progenitors/flask from irradiated nontransplanted Sl/Sld mice. A partial correction of macrocytic anemia was detected 2 months after GBlneor transplantation in splenectomized, irradiated Sl/Sld mice (HgB 7.2 +/- 0.4 g/dL; MCV 68.3 +/- 7.0 fL) compared to splenectomized, irradiated, nontransplanted Sl/Sld mice (HgB 5.5 +/- 1.1 g/dL; MCV 76 +/- 8.5 fL) or control Sl/Sld mice (HgB 5.4 +/- 0.5 g/dL; MCV 82.4 +/- 1.3 fL). Mean RBC volume distribution analysis showed a 2.5-fold increase in percentage of peripheral blood RBCs with MCV less than or equal to 45 fL and confirmed reduction of the MCV in splenectomized- GBlneor-transplanted mice compared to control Sl/Sld mice. A hematopoiesis-suppressive clonal stromal cell line derived from LTBMCs of Sl/Sld mice (Sldneor) engrafted as effectively (43.5% +/- 1.2% G418r CFU-F/limb) as did GBlneor cells (38.3% +/- 0.16% G418r CFU-F/limb) to the irradiated right hind limbs of C57Bl/6 mice. LTBMCs established after 2 or 6 months from Sldneor-transplanted mice showed decreased hematopoiesis (182 +/- 12 [2 months] and 3494.3 +/- 408.1 [6 months] CFU-GEMM forming progenitors/flask over 10 weeks) compared to those established from GBlneor-transplanted mice (5980 +/- 530 [2 months] and 7728 +/- 607, [6 months] CFU-GEMM progenitors forming/flask). Thus, transplantation of clonal bone-marrow stromal cell lines in vivo can stably transfer their physiologic properties to normal or mutant mice.     

Independent regulation of M-CSF and G-CSF gene expression in human monocytes

The macrophage and granulocyte colony-stimulating factors, M-CSF and G- CSF, act in vitro to induce proliferation and differentiation of monocyte and granulocyte progenitor cells, respectively. We show here that both of these CSFs can be produced by stimulated human blood monocytes, but the M-CSF and G-CSF genes are independently regulated. Recombinant human interleukin-3 (IL-3) and GM-CSF primarily induce expression of the M-CSF gene and secretion of M-CSF, whereas bacterial lipopolysaccharide primarily induces expression of the G-CSF gene and secretion of G-CSF. These results suggest that under different conditions of in vitro stimulation the monocyte secretes factors that could lead selectively to either granulocyte or monocyte production.     

A mutation of the common receptor subunit for interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor, and IL-5 that leads to ligand independence and tumorigenicity

The cytokines interleukin-3, interleukin-5, and granulocyte-macrophage colony-stimulating factor bind with high affinity to a receptor complex that contains a ligand-specific alpha-chain and a common beta-chain, h beta c. We report here the isolation of a mutant form of h beta c, from growth factor-independent cells, that arose spontaneously after infection of a murine factor-dependent hematopoietic cell line (FDC-P1) with a retroviral h beta c expression construct. Analysis of this h beta c mutation shows that a small (37 amino acid) duplication of extracellular sequence that includes two conserved sequence motifs is sufficient to confer ligand-independent growth on these cells and lead to tumourigenicity. Because this is a conserved region in the cytokine receptor superfamily, our results suggest that the large family of cytokine receptors has the capacity to become oncogenically active.     

Human erythrocyte antigens: II. The In(Lu) gene regulates expression of an antigen on an 80-kilodalton protein of human erythrocytes

We have previously shown that a murine monoclonal antibody (A3D8) identifies a human erythrocyte protein antigen whose expression is regulated by the Lutheran inhibitor [In(Lu)] gene. In the present study, we demonstrated by immunoprecipitation and Western blot techniques that the antigen defined by A3D8 was on an 80-kD erythrocyte membrane protein. A second 170-kD protein was coprecipitated with the 80-kD protein but failed to show antigen activity by Western blot analysis. The 170-kD protein, when analyzed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis in two dimensions, was composed of 50- and 30-kD disulfide-linked subunits. In(Lu) Lu[a-b-) erythrocytes differed from Lu(a+b+) or Lu(a-b+) erythrocytes in that In(Lu) deoxycholate erythrocyte membrane extracts contained trace amounts of immunoprecipitable 80-kD protein compared with detergent-solubilized erythrocyte membrane extracts prepared from Lu(a+b+) or Lu(a-b+) subjects.     

Improved red blood cell preservation correlates with decreased loss of bands 3, 4.1, acetylcholinestrase, and lipids in microvesicles

In earlier studies we have shown that a final concentration of 0.69% glycerol in blood mixed with an experimental additive solution, EAS 25, improves the in vitro quality and in vivo survival of red blood cells (RBCs). The objective of this study was to determine if the better preservation of RBCs in EAS 25 is correlated with the improved maintenance of membrane lipids and proteins and decreased vesiculation. Split units of RBCs were stored in Adsol or EAS 25 (mmol/L: adenine 2/2, dextrose 122/110, mannitol 42/55, glycerol 0/150, NaCl 154/50). After 12 weeks storage, RBC and microvesicle membranes were analyzed for cholesterol, phospholipid, diphenyl hexatriene fluorescence anisotropy, and acetylcholinesterase (AchE) activity. Bands 3 and 4.1 were identified in the microvesicle membranes by immunoblotting. The RBC membrane cholesterol, phospholipids, and AchE remained higher in EAS 25 than in Adsol (P < .001). Vesicle membrane lipids and AchE in EAS 25 were significantly less than in Adsol (P < .001). The fluidity of stored cells in both the solutions was greater than the prestorage samples. Immunoblotting analyses showed that bands 3 and 4.1 were greatly reduced in the microvesicle membranes shed by the RBCs stored in EAS 25 compared with those formed in Adsol.     

Recombinant human megakaryocyte growth and development factor stimulates thrombocytopoiesis in normal nonhuman primates

Megakaryocyte growth and development factor (MGDF) is a novel cytokine that binds to the c-mpl receptor and stimulates megakaryocyte development in vitro and in vivo. This report describes the ability of recombinant human (r-Hu) MGDF to affect megakaryocytopoiesis in normal nonhuman primates. r-HuMGDF was administered subcutaneously to normal, male rhesus monkeys once per day for 10 consecutive days at dosages of 2.5, 25, or 250 micrograms/kg of body weight. Bone marrow and peripheral blood were assayed for clonogenic activity and peripheral blood counts were monitored. Circulating platelet counts increased significantly (P < .05) for all doses within 6 days of r-HuMGDF administration and reached maximal levels between day 12 and day 14 postcytokine administration. The 2.5, 25.0, and 250.0 micrograms/kg/d doses elicited peak mean platelet counts that were 592%, 670%, and 449% of baseline, respectively. Bone marrow-derived clonogenic data showed significant increases in the concentration of megakaryocyte (MEG)- colony-forming unit (CFU) and granulocyte-erythroid-macrophage- megakaryocyte (GEMM)-CFU, whereas that of granulocyte-macrophage (GM)- CFU and burst-forming unit-erythroid (BFU-e) remained unchanged during the administration of r-HuMGDF. These data show that r-HuMGDF is a potent stimulator of thrombocytopoiesis in the normal nonhuman primate.