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Die Photoelektronenspektren einiger Dicyanmethanido- und Cyanamido- sulfonate bzw. -carboxylate der Typen M[RSO2C(CN)2], M[RSO2NCN] und M[RC(O)NCN] werden mitgeteilt und diese im Vergleich mit den ESCA-Daten von Dicyanamid- und Tricyanmethanid-Derivaten diskutiert. Metal Pseudohalides. XLVII. Spectra of some Dicyanmethanido- and Cyanamido-Sulfonates respectively Carboxylates of the Types M[RSO2C(CN)2], M[RSO2NCN] and M[RC(O)NCN] The X-ray photoelectron spectra of some dicyanmethanido- and cyanamido-sulfonates, respectively, carboxylates of the types M[RSO2C(CN)2], M[RSO2NCN], and M[RC(O)NCN] were recorded and are discussed in comparision with ESCA data of tricyanmethanide and dicyanamide derivatives.

An attempt has been made to characterize the structure of the reaction products resulting from the halogenation of mesophase pitch. FT-i.r. spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction show the presence of halogenated aromatics and hydroaromatics which are of a lower lamellar orientation than in non-halogenated mesophase pitches. The halogenated pitches swell in contact with solvents acting as electron donors or acceptors. Basic organic solvents are the most active swelling agents. A crosslinked structural model is proposed which comprises ordered domains of lamellar aligned aromatics and a disordered network. The crosslinks are bonding regions to join the ordered domains and the disordered material. It is assumed that halogenated hydroaromatic molecules assist in producing the crosslinks.

Das Thema Brustkrebs ist in den vergangenen Jahren zunehmend aus der Tabuzone geruckt. Engagierte Betroffene, die auf Missstande aufmerksam machten, Ergebnisse internationaler Studien, aber auch Skandale wie z. B. in Essen, liesen das offentliche Interesse am Thema Brustkrebs stetig wachsen. In der ernsthaften Auseinandersetzung mit dem Thema zeigt sich deutlich, dass es einer mehrdimensionalen Aufarbeitung bedarf, um den Erfordernissen der Situation angemessene Losungsstrategien zu entwickeln und anzuwenden. Dabei stellt der bisherige Umsetzungsstand zur Einfuhrung eines Disease Management Programms Brustkrebs (DMP) einen Meilenstein dar, von dem ausgehend noch viele weitere Schritte der Verbesserung der Brustkrebsversorgung und deren Rahmenbedingungen folgen mussen.

In order to gain insight into the biological function of a PKC iso-enzyme, the protein kinase Cmu, we analyzed the expression pattern of this protein in mouse epidermis and keratinocytes in culture. Daily analysis of neonatal mouse epidermis immediately after birth showed a time-dependent reduction in the PKCmu content. Expression of the proliferating-cell nuclear antigen (PCNA), indicative of the proliferative state of cells, was reduced synchronously with PKCmu as the hyperplastic state of the neonatal tissue declined. In epidermal mouse keratinocytes, fractionated according to their maturation state, PKCmu expression was restricted to PCNA-positive basal-cell fractions. In primary cultures of those cells, growth arrest and induction of terminal differentiation by Ca2+ resulted in strongly reduced PKCmu expression, concomitantly with the loss of PCNA expression. Treatment of PMK-R1 keratinocytes with 100 nM of the mitogen 12-O-tetradecanoylphorbol-13-acetate (TPA) resulted in activation of PKCmu, reflected by translocation from the cytosolic to the particulate fraction and by shifts in electrophoretic mobility. DNA synthesis was significantly inhibited by the PKCmu inhibitor Goedecke 6976, while Goedecke 6983 did not inhibit PKCmu. Carcinomas generated according to the 2-stage carcinogenesis protocol in mouse skin consistently exhibited high levels of PKCmu. These data correlate PKCmu expression with the proliferative state of murine keratinocytes and point to a role of PKCmu in growth stimulation. A correlation between PKCmu expression and enhanced cell proliferation was also observed for NIH3T3 fibroblasts transfected with and overexpressing human PKCmu.

The Lorentzian widths and the spin-orbit separation of the Al and Mg Kα1 lines have been studied, using photoelectron spectroscopy for the study of x-rays10 and neon and argon as converter atoms. The natural widths of the title lines have been determined. The recommended properties of the Al and Mg Kα1 lines are collected in Table 3.

In the present study, we investigated the role of p53 in the differentiation of epidermal keratinocyte cells. The interrelationship between p53 expression and the various stages of epidermal differentiation and the role of the COOH terminus of the p53 molecule in this process were determined by comparing the expression of the regularly spliced p53 (RSp53) molecule and that of the COOH-terminal alternatively spliced (ASp53) form. p53 mRNA distribution was studied by in situ analysis of frozen skin sections and by reverse transcription-PCR analysis of the various wild-type p53 forms expressed in neonatal skin cell fractions separated by Percoll gradient. p53 protein levels were measured by fluorescence-activated cell sorting analysis and immunohistochemistry, using antibodies that recognize either the COOH terminus of RSp53 or ASp53. The results show that although less mature keratinocyte cells predominantly express the RSp53 form, the more mature cells preferentially express the ASp53 form. Therefore, it is possible that the two p53 forms are associated with different functions required at the various stages of keratinocyte differentiation. The results suggest that the COOH-terminal domain of the p53 molecule is important for its activity in the process of keratinocyte differentiation.

Light-activated receptor currents were measured in Limulus ventral nerve photoreceptors by a two electrode voltage clamp. Short flashes stimulate three different current components (C1, C2, C3). Currents were measured before and after injection of neomycin, heparin and BAPTA. These substances inhibit the inositol phosphate pathway at different stages. Each substance selectively blocked the C2 component. After the block of C2 the other two components could be further stimulated, but their amplitudes were usually reduced. High concentrations of BAPTA, however, increased the amplitude (two-fold) and decay time constant (eight-fold) of C1, suggesting that calcium is necessary for the deactivation of the C1 current.

Senescent cells fail to respond to serum-induced signals for DNA synthesis. Because a central role for the p34cdc2 protein kinase is postulated in control of the cell cycle, we examined the status of this kinase in senescent cells and other growth-arrested cells. In growing human and Syrian hamster fibroblasts, three 35S-labeled proteins of 34-36 kDa were immunoprecipitated with p34cdc2 antiserum. Only the two slower migrating forms were phosphorylated as determined by 32P labelling. In senescent cells, which failed to incorporate [3H]thymidine, no p34cdc2 protein was synthesized and very little or no cdc2 mRNA was observed. When maintained for 48 h in 0.5% serum, young cells also retained only marginal cdc2 expression. After stimulation of low serum-arrested cells by addition of 10% serum, a time-dependent increase of cdc2 mRNA was observed, whereas serum stimulation of senescent cells did not increase cdc2 mRNA. In contrast to senescent and low serum-arrested cells, cdc2 mRNA was expressed at normal levels in cells partially growth arrested by isoleucine deficiency in G1, by aphidicolin at G1-S, by etoposide in G2, or by Colcemid in the M phase of the cell cycle, indicating that cdc2 down-regulation does not always occur upon growth arrest. Following transfection of a plasmid containing the human CDC2 gene into hamster cells, expression of human cdc2 failed to overcome the block to DNA synthesis in senescent cells. Although p34cdc2 was synthesized in the transfected cells, the multiple phosphorylated forms of the proteins were not observed. Taken together, these data support the concept that a chain of events leads to senescence. While p34cdc2 kinase may be one of the critical elements, other cell cycle controls are also involved.

Epidermal G1-chalone and transforming growth factor-beta (TGF beta), two endogenous inhibitors of epidermal cell proliferation, were compared with regard to several effects on epidermis in vivo and in vitro. Both factors inhibited DNA labeling in a rat tongue epithelial cell line, with similar kinetics and half-maximal effects at approximately 1 pg/ml (enriched chalone) and 1 ng/ml (TGF beta). For primary neonatal mouse keratinocytes, TGF beta was found to be a rather strong inhibitor of cell proliferation, whereas chalone showed only a weak effect on cells grown in medium containing 1.2 mM Ca2+ and no effect at all in the presence of 0.06 mM Ca2+. Vice versa, upon i.p. injection, only chalone was able to inhibit mouse epidermal DNA synthesis in vivo, whereas TGF beta had no effect at all. A moderate increase of transglutaminase activity in neonatal primary mouse keratinocytes was induced by both factors at concentrations of about 300 pg TGF beta/ml and 10 pg chalone fraction/ml. Chalone did not compete with [125I]TGF beta for specific binding sites on primary murine keratinocytes. A polyclonal "chalone antiserum" did not interact with TGF beta, and a neutralizing TGF beta antibody that inhibited the effect of TGF beta on cell proliferation could not block the inhibitory effect of chalone on RTE2 cells. In contrast to TGF beta, epidermal G1-chalone did not induce proliferation of NIH-3T3 cells. These results indicate that epidermal G1-chalone and TGF beta are two different inhibitors of epidermal cell proliferation.

Holographic gratings with grating periods between 0.37 μm and 4.4 μm, respectively, were recorded on the surface of TS-diacetylene single crystals by two interfering 257 nm laser beams. Diffraction efficiencies of up to 35 % were obtained for readout with red light of λ = 633 nm. The main modulation mechanism was phase modulation. The spatial resolution was better than 1600 lines/mm. The upper limit of the polymer chain length was 0.6 μm. The holographic sensitivity was 4.5 cm2/J for immediate read-out at 633 nm without processing after exposure. — A weakly exposed latent hologram may be developed simply by gentle annealing the crystal which increases the sensitivity by one order of magnitude.

X.p.s. was used to study the surface composition of dealuminated zeolites including the parent zeolite NaY and ammonium exchanged samples. The dealumination was performed by thermochemical treatment of the ammonium exchanged samples and by extraction with EDTA. For NaY and the ammonium exchanged samples no difference in the Al Si and Na Si ratios between bulk and surface is observed. The Al Si ratios of the external layers show for the thermochemically dealuminated zeolites a strong dependence on the temperature of treatment and can become, at high temperatures, up to three times higher than that of the bulk. The enrichment of aluminium in the surface is interpreted as accumulation of non-framework aluminium species which migrate out of the micropore system towards the zeolite surface. The aluminium extraction with EDTA favours the external layers of the crystals.

A method for providing a calibrant metal deposit on a sample surface suitable for static charge referencing is presented. The reference metal deposit consists of well defined particles which were prepared as a colloidal metal dispersion.

The specific action of a pig skin fraction enriched in epidermal G1-chalone, a tissue-specific inhibitor of epidermal DNA synthesis, was investigated by means of flow cytofluorometry. The results indicate that G1-chalone inhibits progression of partially synchronized rat tongue epithelial cells (line RTE-2) through the cell cycle at a point 2 h prior to the beginning of the S-phase. Approximately 8 h after chalone addition, the cells can overcome the inhibition and begin to enter the S-phase. The duration of this delay is concentration-independent, but the fraction of cells affected is proportional to the chalone concentration. The progression of cells which already have entered S-phase is not affected. In contrast to the G1-chalone preparation, aphidicolin, a potent inhibitor of DNA polymerase alpha, clearly shows S-phase-specific inhibition. These results indicate that the epidermal G1-chalone inhibits epidermal cell proliferation in a fully reversible manner by a highly specific effect on cell cycle traverse.

The interference pattern by two 257 nm laser beams is recorded by photopolymerization of a fresh monomeric PTS-diacetylene single-crystal surface as a thin, plane-wave hologram. Without past-exposure processing, the hologram is read out by the red light of a helium—neon laser. The advantage of PTS as a photochemical recording system is supposed to be an excellent spatial resolution.

The aim of this paper is to present the results, of 3-D calculations, on the interferences between a dipole and a quadrupole magnet in the CERN Antiproton Collector lattice.

An KF-Einkristallen wurden Messungen über die Argon-Diffusion im Temperaturbereich von 400 — 800°C durchgeführt. Die Meßergebnisse lassen sich darstellen durch die ARRHENiussche Beziehung mit einem D0 = 80 cm2 sec-1 und einer Aktivierungsenergie von Q= (1,8 ± 0,1) eV. Bei KF-Preßlingen ist der Gasaustritt weitgehend abhängig von der thermischen Vorbehandlung.

Die „Internationalen Gesundheitsvorschriften“ (IGV) wurden am 25. Mai 1951 von der Weltgesundheitsorganisation (WHO) zur „Bekampfung der quarantanepflichtigen ubertragbaren Krankheiten“ erlassen. Dadurch wurden 12 internationale Sanitatskonventionen oder ahnliche Vereinbarungen auser Kraft gesetzt. Den Vorschriften ist die Bundesrepublik mit Gesetz vom 21. Dezember 1955 (Bundesgesetzbl. II, S. 1060) beigetreten. Das Hauptziel der internationalen Zusammenarbeit auf dem Gebiet des offentlichen Gesundheitswesens ist, wie es in der Praambel heist, die Ausrottung von Krankheiten. Die Internationalen Gesundheitsvorschriften seien besser als die bisherigen Bestimmungen „auf die verschiedenen internationalen Verkehrsmittel“, wie Schiffe, Luftfahrzeuge usw., abgestimmt und wurden die „hochstmogliche Sicherheit gegen die internationale Verbreitung von Krankheiten mit dem geringsten Ausmas an Eingriffen in den Weltverkehr“ gewahrleisten. Von den quarantanepflichtigen Krankheiten Pest, Cholera, Gelbfieber, Pocken, Fleckfieber und Ruckfallfieber interessieren uns heute aus Anlas der vorjahrigen Erkrankungen an Pocken in Ansbach, Dusseldorf, Aachen und im Kreis Monschau die internationalen Vorschriften zur Bekampfung der Pocken Die meisten Staaten sind der IGV beigetreten; fast alle Staaten haben die Vorschriften hinsichtlich der Pocken ohne Vorbehalt angenommen und damit als verbindlich anerkannt.

Wahrend die Reinigung eines Impfstoff es von seinen Ballaststoff en eine Forderung des Klinikers und des Immunbiologen ist, um unerwunschte Nebenwirkungen auszuschalten, richtet sich der Wunsch des Impfarztes auf einen gefriergetrockneten Impfstoff, weil er damit ein lange haltbares und in seiner Wirkung gleichmasiges und verlasliches Substrat in die Hand bekommt.

Das Auftreten der Pocken in Deutschland und die dadurch angeregten Publikationen haben wohl die Mehrzahl der deutschen Arzte mit dem Wesen der Infektion wieder vertraut gemacht. Andererseits bestehen vielfach noch Unklarheiten uber Zusammenhange und Eigentumlichkeiten der Pathogenese, so das es zweckmasig ist, zum Verstandnis der Klinik hierauf nochmals kurz einzugehen, selbst auf die Gefahr hin, Bekanntes zu wiederholen.