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Biological invasions erode ecosystem functioning and occur more frequently in freshwater ecosystems than in terrestrial environments. Nonphysical deterrents may be used to limit invasive fish dispersal, without altering the streamflow or connectivity of a watershed. Little is currently known about how behavioral variation among individuals may affect the efficacy of a deterrent, although such variation has been shown to affect fish dispersal in other contexts, such as range expansion. Furthermore, deterrent effectiveness is rarely tested when fish are motivated to disperse. Across a control, CO2, and CO2+ deterrent treatment, we quantified the avoidance response of invasive Common Carp Cyprinus carpioto a combined acoustic‐stroboscopic deterrent. In the CO2treatment, we motivated individuals to enter a novel environment by degrading the home chamber of a choice arena with a continuous infusion of CO2. In the CO2+ deterrent treatment we introduced acoustic and stroboscopic stimuli to delay the departure of the fish and evaluate the efficacy of the deterrent. Finally, we tested a subset of the fish multiple times to determine whether they consistently responded to the same concentration of CO2. We found that the acoustic and stroboscopic deterrent could detain the fish in an increasingly unfavorable environment. Common Carp took only 195 and 131 s, respectively, to swim between the chambers during the control and CO2treatment but took an average of 596 s in the CO2+ deterrent treatment. High CO2concentrations in the CO2+ deterrent treatment led to most fish eventually dispersing toward the deterrent stimuli. Avoidance behavior varied widely within the CO2+ deterrent treatment, and Common Carp expressed repeatable differences in the tank‐inflow CO2concentrations that were observed during chamber departure. Such interindividual variation in deterrent avoidance indicates that some individuals within a given species are more likely to move past a deterrent than others.

Der Großteil der Wachstumsstörungen der Wirbelsäule ist erworben und deren Ätiologie noch immer unbekannt. Sowohl bei den Skoliosen als auch bei den sagittalen Profilstörungen kommen die idiopathischen Formen am häufigsten vor. Die Ätiologie ist multifaktoriell und neben genetischen, hormonellen und mechanischen Faktoren scheinen auch Stoffwechselkomponenten mitbeteiligt zu sein. Das Progressionsrisiko einer bestehenden Deformität ist während des pubertären Wachstumsschubs besonders hoch. Entsprechend sollten in dieser vulnerablen Phase regelmäßige klinisch-radiologische Kontrollen erfolgen. Neuerdings werden unter Berücksichtigung der in den letzten Jahren gewonnenen Erkenntnisse über den Zusammenhang von Wirbelsäulen- und Thoraxwachstum und der damit verbundenen Lungenreifung die Deformitäten weniger nach ihrer Ätiologie, als vielmehr nach dem Zeitpunkt der Diagnosestellung eingeteilt. Unter dem Begriff Early-Onset-Skoliosen werden dementsprechend alle Deformitäten der Wirbelsäule subsumiert, welche vor dem 10. Lebensjahr nachgewiesen werden. Bei Versagen der so lange wie möglich einzusetzenden konservativen Therapien sollten definitive Fusionen durch Verwendung wachstumslenkender operativer Techniken hinausgezögert und damit eine den Umständen entsprechend optimale Lungenfunktion angestrebt werden. The majority of growth disturbances of the spine are acquired and their etiology is still unknown. Both scolioses and sagittal profile disorders are most commonly of idiopathic origin. The etiology is multifactorial and besides genetic, hormonal and mechanical factors also metabolic components seem to be involved. The risk of progression of an existing deformity is particularly high during the pubertal growth spurt. Accordingly, regular clinical and radiological controls should be carried out in this vulnerable period. Recently, spinal deformities have been classified according to the time of diagnosis rather than according to their etiology, considering the increasing knowledge about the correlation between spinal and thoracic growth and the associated maturation of the lungs. Therefore, the term “early onset scoliosis” considers all deformities of the spine diagnosed before the age of 10 years. In the case of failure of conservative treatment options, which have to be applied for as long as possible, definitive spinal fusion surgery should be delayed by the use of growth-sparing surgical techniques, aiming to achieve as normal pulmonary function as possible.

We reviewed 15 patients, nine girls and six boys, with chronic anterior dislocation of the radial head which was treated by ulnar osteotomy, external fixation and open reconstruction of the elbow joint but without repair of the annular ligament. Their mean age was 9.5 years (5 to 15) and the mean interval between the injury and reconstruction was 22 months (2 months to 7 years).All radial heads remained reduced at a mean follow-up of 20 months (6 months to 5 years). Normal ranges of movement for flexion, extension, pronation and supination were unchanged in 96.1% (49/51) and worse in 3.9% (2/51). Limited ranges of movement were improved in 77.8% (7/9), unchanged in 11% (1/9) and further decreased in 11% (1/9).There were two superficial pin-track infections and two cases of delayed union but with no serious complications. Reconstruction of the radiocapitellar joint is easier using external fixation since accurate correction of the ulna can be determined empirically and active functional exercises started immediately. Only patients with a radial head of normal shape were selected for treatment by this method.

The purpose of this investigation was to assess whether alterations in the fatty acid composition of rat liver epithelial (WB-F344) cell phospholipids would modulate gap junction-mediated intercellular communication (GJIC). WB-F344 cells were grown to confluency in culture medium supplemented with one of seven different fatty acids at a concentration of 50 microM for 48 h. Only alpha-linoleate (18:3 n-3) significantly inhibited GJIC. Saturated fatty acids (12:0, 16:0, and 18:0), a monounsaturated fatty acid (18:1 n-9), and n-6 polyunsaturated fatty acids (18:2 and 20:4) did not affect GJIC. The alpha-linolenate-induced inhibition of GJIC was not due to the activation of protein kinase C or intracellular hydroperoxide production, two lipid-dependent parameters previously shown to inhibit GJIC. In addition, alpha-linolenate did not alter membrane fluidity. Although the mechanism by which alpha-linolenate inhibits GJIC is unclear, changes in the fatty acid composition of cell phospholipids may be of critical importance. Subsequent to supplementation with alpha-linolenate, WB-F344 cell phospholipids had reduced 20:4 n-6 and elevated n-3 fatty acids. The results of this investigation emphasize the importance of current research into the influence of lipids on cell function and identify a new mechanism by which gap junctions can be modulated.

Haemodialysis, widely used to treat patients with renal failure, is not always well tolerated. Different mechanisms have been postulated for this. We analyzed the influence of haemodialysis on erythrocyte morphology and blood rheology.

Summary Fibrinolysis induced by the infusion of plasminogen activators into the circulation has been shown to cause coagulation disorders in ascites retransfusion. Dexamethasone is known to inhibit the synthesis of plasminogen activators by peritoneal macrophages. We therefore assessed its potential in preventing the occurrence of fibrinolysis by injecting 16 mg dexamethasone intraperitoneally in 10 patients 24 h before ascites retransfusion was performed. In addition, the effect of dexamethasone upon the activity or concentration of several proteases and antiproteases related to coagulation in plasma and ascites was analyzed on 15 occasions. An increase of the activity of plasminogen, a2-antiplasmin, and antithrombin III, and in the concentration of a1-protease inhibitor in ascites was induced by the dexamethasone injection. However, the reaction was not identical in all patients. Those patients having an increase of plasminogen activities of 0.6 CTA U/ml or more did not show signs of fibrinolysis during retransfusion. The results obtained indicate that intraperitoneal injection of dexamethasone decreases the concentration of plasminogen activators in ascites and thereby reduces the risk of coagulation disorders during retransfusion procedures. Since the effect is variable and not sustained, assessment of preoperative plasminogen concentrations is mandatory in order to prevent complications.