Development of a test system to analyze different hip fracture osteosyntheses under simulated walking

The mechanical complications of osteosyntheses after hip fractures are previously investigated by mostly static or dynamic uniaxial loading test systems. However, the physiologic loading of the hip joint during a normal gait is a multiplanar, dynamic movement. Therefore, we constructed a system to test osteosyntheses for hip fractures under physiologic multiplanar loading representative of normal gait. To evaluate the testing system, 12 femora pairs were tested under 25,000 cycles with two standard osteosyntheses (Proximal Femoral Nail Antirotation/Gamma3 Nail). For angular movement, the varus collapse to cut out (proportional to(CO)) (proportional to(CO) = 4.8 degrees +/- 2.1 degrees for blade and proportional to(CO) = 7.8 degrees +/- 3.8 degrees for screw) was the dominant failure mode, and only slight rotational angle shifts (proportional to(Rot)) (proportional to(Rot) = 1.7 degrees +/- 0.4 degrees for blade and proportional to(Rot) = 2.4 degrees +/- 0.3 degrees for screw) of the femoral head around the implant axis were observed. Angular displacements in varus direction and rotation were higher in specimens reinforced with screws. Hence, the cut out model and the migration directions showed a distinction between helical blade and hip screw. However, there were no significant differences between the different implants. The new setup is able to create clinical failures and allows to give evidence about the anchorage stability of different implant types under dynamic gait motion pattern

Is the rotation of the femural head a potential initiation for cutting out? A theoretical and experimental approach

We conclude the center-center position in the head of femur of any kind of lag screw or blade is to be achieved to minimize rotation of the femoral head and to prevent further mechanical complications

Identification of prolylcarboxypeptidase as the cell matrix-associated prekallikrein activator

Investigations determined that the cell matrix-associated prekallikrein (PK) activator is prolylearboxypeptidase. PK activation on human umbilical vein endothelial cell (HUVEC) matrix is inhibited by antipain (IC50 = 50 muM) but not antifactor XIIa antibody, 3 mM benzamidine, 5 mM iodoacetic acid or iodoacetamide, or 3 mM N-ethylmaleimide. Corn trypsin inhibitor (IC50 = 100 nM) or Fmoc-aminoacylpyrrolidine-2-nitrile (IC50 = 100 muM) blocks matrix-associated PK activation. Angiotensin II (IC50 = 100 muM) or bradykinin (IC50 = 3 mM), but not angiotensin 1-7 or bradykinin 1-5, inhibits matrix-associated PK activation. ECV304 cell matrix PK activator also is blocked by 100 muM angiotensin II, 1 muM corn trypsin inhibitor, and 50 muM antipain, but not angiotensin 1-7. 1 mM angiotensin 11 or 300 muM Fmoc-aminoacylpyrrolidine-2-nitrile indirectly blocks plasminogen activation by inhibiting kallikrein formation for single chain urokinase activation. On immunoblot, prolylcarboxypeptidase antigen is associated with HUVEC matrix. These studies indicate that prolylearboxypeptidase is the matrix PK activator. (C) 2002 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.Univ Michigan, Div Hematol & Oncol, Dept Internal Med, Ann Arbor, MI 48109 USAUniversidade Federal de São Paulo, Dept Bioquim, São Paulo, BrazilUniv Michigan, Dept Pathol, Ann Arbor, MI 48109 USAUniversidade Federal de São Paulo, Dept Bioquim, São Paulo, BrazilWeb of Scienc

Spielend Lernen im Kindergarten. Neue Technologien im Einsatz

Dieses Kapitel behandelt den kindlichen Zugang zu neuen Technologien im Alltag. Da die Kinder von heute in einer Medienwelt aufwachsen und schon früh mit Medien und Medienprodukten in Kontakt kommen und diese auch nutzen, sind die vorschulischen Bildungsinstitutionen gefordert, aktive Medienarbeit zu leisten und dabei einen verantwortungsbewussten Umgang mit Medien zu fördern. In engem Zusammenhang mit dem Einsatz von neuen Technologien im Vorschulbereich steht die Medienbildung. Deren Förderung stellt schon in der frühen Mediennutzung eine Notwendigkeit dar und wird in diesem Kapitel anschaulich mit ihren wichtigsten Zieldimensionen beschrieben. Die Autorinnen und Autoren verweisen auf die spielerische Umsetzung medienpädagogischer Ziele und den damit verbundenen Einsatz von neuen Technologien. Die Förderung der Medienbildung lässt sich in der Kindergartenarbeit nicht losgelöst von anderen Bildungsschwerpunkten vollziehen und ist somit immer verknüpft mit unterschiedlichen Bereichen der kindlichen Entwicklung und Förderung. Beispiele aus der Praxis zeigen die sozialen, kommunikativen, lernmethodischen, spielerischen und bildenden Aspekte des Lernens und Lehrens mit neuen Technologien sowie die damit zusammenhängenden Herausforderungen und Hindernissen. (DIPF/Orig.

Standardised cement augmentation of the PFNA using a perforated blade: A new technique and preliminary clinical results. A prospective multicentre trial

Producción CientíficaPertrochanteric fractures are a rising major health-care problem in the elderly and their operative stabilisation techniques are still under discussion. Furthermore, complications like cut-out are reported to be high and implant failure often is associated with poor bone quality. The PFNA1 with perforated blade offers a possibility for standardised cement augmentation using a polymethylmethacrylate (PMMA) cement which is injected through the perforated blade to enlarge the load-bearing surface and to diminish the stresses on the trabecular bone. The current prospective multicentre study was undertaken to evaluate the technical performance and the early clinical results of this new device. In nine European clinics, 59 patients (45 female, mean age 84.5 years) suffering from an osteoporotic pertrochanteric fracture (Arbeitsgemeinschaft fu¨ r Osteosynthesefragen, AO-31) were treated with the augmented PFNA1. Primary objectives were assessment of operative and postoperative complications, whereas activities of daily living, pain, mobility and radiologic parameters, such as cement distribution around the blade and the cortical thickness index, were secondary objectives. The mean follow-up time was 4 months where we observed callus healing in all cases. The surgical complication rate was 3.4% with no complication related to the cement augmentation. More than onehalf of the patients reached their prefracture mobility level within the study period. A mean volume of 4.2 ml of cement was injected. We did not find any cut-out, cut through, unexpected blade migration, implant loosening or implant breakage within the study period. Our findings lead us to conclude that the standardised cement augmentation using the perforated blade for pertrochanteric fracture fixation enhances the implant anchorage within the head–neck fragment and leads to good functional results

Probing conformational states of glutaryl-CoA dehydrogenase by fragment screening

The first crystal structure is reported of a glutaryl-CoA dehydrogenase in the apo state without flavin adenine dinucleotide cofactor bound. Additional structures with small molecules complexed in the catalytic active site were obtained by fragment-based screening

It\u27s Time to Pack Away the Crystal Ball: The Need for Remand in Pleading and Proof Cases of First Impression in Nebraska

I. Introduction II. If Only I Knew What to Plead ... A. To Appeal or to Amend—The $64,000 Question ... B. The Advantages of Modifying the No-Remand Rule … C. The Unfairness of Affirming on Grounds Other Than Those Relied on by the Trial Court III. If Only I Knew What to Prove ... A. The Unfairness of Applying New Proof Requirements Retroactively ... B. The Strange Case of Damages IV. Conclusio