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Die Spektroskopie schmaler Resonanzen ist ein Schlusselbaustein vieler moderner Anwendungen. Pulse moderner Rontgenlichtquellen sind jedoch spektral viel breiter als die zu untersuchenden Resonanzen, so dass nur ein kleiner Teil des Lichts wechselwirkt und zum Signal beitragt. Kurzlich ist es unserem Team gelungen, solche Pulse so zu manipulieren, dass zuvor ungenutzte Photonen in Resonanz geschoben werden. Die „gescharften“ Rontgenpulse eroffnen eine Vielzahl von Anwendungen.

The following on new requirements of endoscopy contains commentaries on the risk of infection in endoscopy, the need to eliminate contamination, and the use of a disposable system in transnasal endoscopy.

Summary Background: Accurate pre-operative or intra-operative labeling of the skin is often necessary to mark exactly the surgical excision lines. Pre-operative “unsterile” permanent skin labeling systems are needed for example for vein and sentinel lymph node surgery; here the dyes must resist two surgical skin disinfection procedures. In contrast, excision borders are labeled during surgery using a “sterile” skin marking system. Methods: Many commercial and non-commercial pre- and intra-operative skin-labeling systems are available, such as autologous patient blood, fluorescence triphenylmethane dyes and commercial skin markers. The available skin marking systems have specific advantages and disadvantages. We review the different labeling systems, offering guidelines to help choose a cost-effective system appropriate for a given surgical procedure. Results: The Edding® permanent markers 400 und 3000 are well suited for preoperative skin labeling and less expensive than commercial skin labeling systems. Autologous patient blood and eosin are well suited for intra-operative labeling and are most cost effective. Eosin Y is widely used and well suited for labeling of dark skin, bone, cartilage, and muscle tissue and spares the expense of expensive commercial skin markers. Conclusion: Knowledge of the many commercial and non-commercial pre- and intra-operative skin labeling systems and their advantages and disadvantages helps to reduce the use of relatively expensive commercial skin markers.

The introduction of dynamic intensity modulation into radiotherapy using conventional photon beams or scanning particle beams requires additional and efficient methods of dose verification. Dose measurements in dynamically generated dose distributions with a single ionization chamber require a complete application of the treatment field for each single measurement. Therefore measurements are performed by simultaneous use of multiple ionization chambers. The measurement is performed by a computer controlled system and is comprised of the following steps: (a) automated positioning of the ionization chambers, (b) measurement at these points, (c) a comparison with the calculated dose from the treatment planning system, and (d) documentation of the measurement. The ionization chambers are read out by a multichannel electrometer and are densely packed into a mounting of polymethylmetacrylate, which is attached to the arm of a three-dimensional motor-driven water phantom. The measured and planned dose values are displayed numerically as well as graphically. The mean deviation between measured and planned doses as well as their standard deviation are calculated and displayed. Through printouts complete documentation of the measurement is obtained and a quick decision can be made whether the dose distribution is acceptable for the patient. The system is now routinely used for dose verification at the heavy ion therapy project at the Gesellschaft für Schwerionenforschung in Darmstadt. Up to now 242 measurements have been performed for heavy ion treatment of 30 patients. The system allows efficient verification and documentation of carbon ion fields and is in principle also applicable to intensity-modulated photon beams.

The 2,3-disubstituted 6-fluoro-7-(4-methyl-1-piperazinyl)-quinoxalines (3–11) were synthesized for bioassay via reaction of 1.2-diamino-4-fluoro-5-(4-methyl-1-piperazinyl)benzene (2) with the appropriate 1,2-dicarbonyl compounds. However, none of the tested compounds 3–11 showed significant in vitro activ ity against E. coli ATCC11229, S. aureus ATCC6538 and C.albicans SATCC10231.

The 2,3-disubstituted 6-fluoro-7-(4-methyl-1-piperazinyl)-quinoxalines (3–11) were synthesized for bioassay via reaction of 1.2-diamino-4-fluoro-5-(4-methyl-1-piperazinyl)benzene (2) with the appropriate 1,2-dicarbonyl compounds. However, none of the tested compounds 3–11 showed significant in vitro activ ity against E. coli ATCC11229, S. aureus ATCC6538 and C.albicans SATCC10231.

A new class of 4-deoxy-4-([4-substituted-1-piperazinyl], [4-morpholinyl] and [4-(perhydrol, 4-thiazin-4-yl)])-2,3-anhydrolyxopyranosides (3a-g and 6a-g) were synthesized from epoxy triflate moities 2 and 5 and 4-substituted piperazines, morpholines and perhydro-1,4- thiazines, respectively, to test their antibacterial activity. The characterized series of new compounds was tested in vitro against E. coli ATCC11229, S. aureus ATCC6538 and C. albicans SATCC10231.