Specific inhibition of the Survivin-CRM1 interaction by peptide-modified molecular tweezers

Survivin's dual function as apoptosis inhibitor and regulator of cell proliferation is mediated via its interaction with the export receptor CRM1. This protein-protein interaction represents an attractive target in cancer research and therapy. Here, we report a sophisticated strategy addressing Survivin's nuclear export signal (NES), the binding site of CRM1, with advanced supramolecular tweezers for lysine and arginine. These were covalently connected to small peptides resembling the natural, self-complementary dimer interface which largely overlaps with the NES. Several biochemical methods demonstrated sequence-selective NES recognition and interference with the critical receptor interaction. These data were strongly supported by molecular dynamics simulations and multiscale computational studies. Rational design of lysine tweezers equipped with a peptidic recognition element thus allowed to address a previously unapproachable protein surface area. As an experimental proof-of-principle for specific transport signal interference, this concept should be transferable to any protein epitope with a flanking well-accessible lysine.

Functional Disruption of the Cancer-Relevant Interaction between Survivin and Histone H3 with a Guanidiniocarbonyl Pyrrole Ligand

The protein Survivin is highly upregulated in most cancers and considered to be a key player in carcinogenesis. We explored a supramolecular approach to address Survivin as a drug target by inhibiting the protein-protein interaction of Survivin and its functionally relevant binding partner Histone H3. Ligand L1 is based on the guanidiniocarbonyl pyrrole cation and serves as a highly specific anion binder in order to target the interaction between Survivin and Histone H3. NMR titration confirmed binding of L1 to Survivin's Histone H3 binding site. The inhibition of the Survivin-Histone H3 interaction and consequently a reduction of cancer cell proliferation were demonstrated by microscopic and cellular assays.

[Proposals for adapting a DRG system in the fields of orthopedics and trauma surgery for 2004]

The introduction of the DRG system in Germany-optional since 1 January 2003 and mandatory for all hospitals as of 1 January 2004-has resulted in great uncertainty, particularly on the part of hospitals, since apprehension prevails that the diagnostic and therapeutic measures practiced in Germany will not be appropriately represented and remunerated by a DRG system. The G-DRG version 1.0 prepared within the framework of substitutive execution is largely identical to the Australian AR-DRG version 4.1. Adjustments that do justice to the realities of German treatment modalities were at most insignificant. It is therefore essential that stock be taken for each medical specialty to determine to what extent treatment procedures commonly followed in Germany are adequately reflected in this G-DRG system or whether adjustments are necessary to make allowances for German realities. To be able to provide qualified statements on the problems involved, scientific analysis of possible problems is necessary utilizing German data. Thus, we undertook an evaluation of how the special fields of orthopedics and accident surgery are represented in the G-DRG system. The resultant data form the basis for evidence of presumable deficits in the representation of orthopedic and accident surgery cases in the G-DRG system. The German Association for Trauma Surgery and the German Association for Orthopedics and Orthopedic Surgery have undertaken a DRG evaluation project together with the Organization of Directors for Accident Surgery (chairperson: Professor Dr. Mischkowsky, Kempten), the Organization of Directors for Orthopedics (chairperson: Professor Dr. Puhl, Ulm), the DRG Working Group of the German Association for Accident Surgery, and the Joint Commission of the Professional Association of German Surgeons and the German Association for Surgery in cooperation with the DRG Research Group of the University Clinic Muenster, the German Hospital Association, and the German Medical Association with the goal of examining the medical and economic homogeneity of the case groups. A total of 12,645 orthopedic and trauma surgery cases were collected from 23 clinics-11 university hospitals and 12 non-university hospitals-and assessed. On the basis of this database and when too few cases were evaluable also based on clinical considerations, 14 adjustment proposals were formulated and submitted on schedule on 31 March 2003 to the Institute for Hospital Remuneration. The results of the DRG evaluation project illustrated the problems involved in representing the exceedingly heterogeneous and complex activities of orthopedic and trauma surgery departments in a flat rate financing system that is not attuned to the realties of German treatment procedures. Version 1.0 of the G-DRG system is not sufficiently differentiated to represent the multifaceted diagnostic and therapeutic services provided by trauma surgery and orthopedic departments in Germany.

[Congophilic (amyloid) deposits in the bursa tendinis calcanei]

Eosinophilic deposits in the bursa tendinis calcanei were identified as congophilic material. It was shown that the incidence of these depositions increased with age and it is concluded that the bursal wall is prone to senile amyloidosis, like other articular tissues.