Gene delivery: A single nuclear localization signal peptide is sufficient to carry DNA to the cell nucleus

Translocation of exogenous DNA through the nuclear membrane is a major concern of gene delivery technologies. To take advantage of the cellular import machinery, we have synthesized a capped 3.3-kbp CMVLuciferase-NLS gene containing a single nuclear localization signal peptide (PKKKRKVEDPYC). Transfection of cells with the tagged gene remained effective down to nanogram amounts of DNA. Transfection enhancement (10- to 1,000-fold) as a result of the signal peptide was observed irrespective of the cationic vector or the cell type used. A lysine to threonine mutation of the third NLS amino acid completely abolished these remarkable features, suggesting importin-mediated translocation. Our hypothesis is that the 3-nm-wide DNA present in the cytoplasm is initially docked to and translocated through a nuclear pore by the nuclear import machinery. As DNA enters the nucleus, it is quickly condensed into a chromatin-like structure, which provides a mechanism for threading the remaining worm-like molecule through the pore. A single NLS signal is thus sufficient, whereas many signals on a gene would actually inhibit entry, the same DNA molecule being threaded through adjacent pores.     

Comparison of measurements obtained with hand files or the Canal Leader attached to electronic apex locators: an in vitro study

AIM: The aim of the present in-vitro study was to combine directly the Canal Leader handpiece (SET, Olching, Germany) with the electronic apex locators ROOT ZX (Morita, Kyoto, Japan) and JUSTY (Yoshida, Tokyo, Japan) to find out whether the working length values thus obtained were identical to those resulting from the combination of the same electronic devices with hand files. METHODOLOGY: A total of 50 natural extracted teeth with single canals and mature apices were used. A radiograph was used as a control and the distance from the radiographic apex to the tip of the file was measured and compared with the results of the electronic length determination. RESULTS: For both electronic devices the differences amongst the distribution of the measurements were not statistically significant under the specified conditions (P > 0.05), indicating that the measurements with hand files and with the Canal Leader were identical for the majority of the cases. CONCLUSIONS: Under the conditions of this study the working length of canals obtained with electronically assisted hand files were similar to those obtained with the electronically assisted mechanical handpiece Canal Leader.     

Der Reflexcharakter der Adaptationsvorgänge,insbesondere der Dunkeladaptation,und deren Beziehungen zur topischen Diagnose und zur Hemeralopie

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Sehnervenentzündungen bei Störungen der inneren Sekretion im Verlauf der Adipositas dolorosa (Dercumschen Krankheit)

Ohne ZusammenfassungNach einem im Verein Norddeutscher Psychiater und Neurologen gehaltenen Vortrag.     

Beiträge zur Kriegsverletzung des Gehörorgans

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Historical development of alloplastic temporomandibular joint replacement before 1945

Resections of the temporomandibular joint (TMJ) have been carried out for about 150 years. This article reviews the beginning of TMJ surgery technique before 1945 by carrying out extensive inquiries in public and private libraries and collections. Before 1945 the technique of alloplastic reconstruction of the TMJ was mainly influenced by German and French surgeons. Reconstruction was limited to replacement of the condyle. The role of the TMJ within the orofacial system was not considered. Interposition of alloplastic implants, resection dressings and prostheses were the dominant technique. The main concerns were sterilisation, biocompatibility and implant fixation. No evidence-based data on outcomes are available from that time. By 1945 reconstruction of the TMJ involved the close cooperation of surgeons and dentists.