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Die Einteilung der Pneumonien richtet sich neben klinischen und pathologischen vor allem nach ätiologischen Gesichtspunkten. Es werden diesbezüglich die respirato- bzw. pneumotropen Viren vorgestellt, daneben differentialdiagnostisch wichtige andere Infektionserreger der "Viruspneumonie" (M. pneumoniae, Chlamydia psittaci, Coxiella burnetii) beschrieben und ihre klinischen Aspekte, labordiagnostischen Möglichkeiten sowie die Aussagekraft der verschiedenen Nachweisverfahren diskutiert. Die Letalität der primär virusbedingten Pneumonien ist zwar niedrig, der respiratotrope Virusbefall kann aber Schrittmacher für schwerebakterielle Superinfektionen sein.
Wir haben einen kommerziell verfügbaren Test zur Bestimmung von Thyroxin (T4) am Analysensystem RA1000 auf seine Eignung in unserem Labor untersucht. Das Prinzip des Tests beruht auf einer immunturbidimetrischen Inhibitionstechnik, die besonders zur Messung niedriger T4-Konzentrationen geeignet ist Es wurde eine Präzision (in Serie, von Tag zu Tag) zwischen 2,6 und 4,6% (VK) ermittelt. Die Richtigkeit wurde untersucht an Patientenproben mit 2 Vergleichsmethoden und vergleichend zu den Sollwerten kommerziell verfügbarer Richtigkeitskontrollseren. Der Vergleich an Patientenproben ergab eine gute bis akzeptable Übereinstimmung, der Vergleich mit den Sollwerten von Richtigkeitskontrollseren zeigte in einigen Seren gewisse methodische Differenzen. Insgesamt ergaben unsere Untersuchungen, daß die immunturbidimetrische Inhibitionstechnik am HA-1000 eine schnelle und zuverlässige Bestimmung der T4-Konzentration ermöglicht.
(±)-Aeroplysinin-1, an optically active 1.2-dihydroarene-1.2-diol. was isolated from the marine sponges Verongia aerophoba (+-isomer) and lanthella ardis (--isomer). For the experiments presented we used the +-isomer from Verongia aerophoba. Here we describe the hitherto unknown biological and pharmacological property of this compound to display pronounced anticancer activity against L5178y mouse lymphoma cells (ED50: 0.5 μm). Friend erythroleukemia cells (ED50: 0.7μm) , human mamma carcinoma cells (ED50: 0.3μm) and human colon carcinoma cells (ED50: 3.0 μm) in vitro. Furthermore, aeroplysinin caused a preferential inhibition of [3H]thymidine (dThd) incorporation rates in L5178y mouse lymphoma cells if compared with murine spleen lymphocytes in vitro. At concentrations between 1.1 and 28.5 μm, the [3H]dThd incorporation rates in L5178y cells were suppressed to 28% -0% but only to 78% -18% in murine spleen lymphocytes. The same differential effect in vitro was found with the following epithelial cells: 14.70 μm of the compound were required to inhibit normal human fibroblasts to 50% , but only 2.9 μm in the assays with human malign keratinocytes or malignant melanoma cells to observe the same inhibitory effect. Moreover, aeroplysinin-1 displayed antileukemic activity in vivo using the L5178y cell/NMRI mouse system; administered at a dose of 50 mg/kg for five consecutive days, the T/C (% ) value was determined to be 338. Preliminary toxicology studies revealed an acute LD50 of 202 mg/kg and a subacute LD50 of 150 mg/kg. Aeroplysinin-1 is neither a direct mutagen nor a premutagen in the umu/Salmonella typhimurium test system.
The cyanobacterium Synechococcus leopoliensis (Anacystis nidulans, strain L 1402-1) grown at 39 °C and 2 vol. % CO : could be synchronized by a light/dark regime of 3:5 h (white light intensity 1.5 × 104 erg cm-2 sec-1). Content of pigments (chlorophyll a. phycocyanin and carotenoids), R N A and proteins increased linearly up to 100% at the end of the light period while DNA synthesis was lower. Chlorophyll a synthesis was correlated to the photosystem I activity of the isolated thylakoids and to the formation of MGD G . Galacto lipids were synthesized in the light period, only. A lag phase of 2h was observed in the biosynthesis of SQDG and PG. No significant differences were found between the cell and thylakoid fractions. Palmitic (C16:0), hexadecenoic (C16:1) and octadecenoic (C18:1) acid as major com ponents accounted for more than 90% of total fatty acids in MGD G , DGDG and SQDG . PG contains a small amount of stearic (C18:0) and heptadecenoic (C17:1) acid. No significant variations in the fatty acid distribution of all lipids could be detected in the cell fraction during the division cycle. Changes in the ratio of saturated to unsaturated fatty acids were found in isolated thylakoids. only. In experiments with [14C]bicarbonate main radioactivity was measured in galacto lipids while using [14C]acetate SQDG and PG were markedly [14C]labelled. Results were discussed with reference to the findings of eucaryotic algae and the formation of photosynthetic membranes.
Raney nickel, a highly reactive and air-sensitive solid, if prepared and investigated under oxygen-free conditions, exhibits interesting catalytic properties. Using photoelectron spectroscopy for real-time gas analysis in a flow reactor, the following results are obtained with alkyl and acylhalides: Dehydrohalogenation temperatures are lowered relative to thermal HHal elimination up to 350 K. Monochloro and bromo propanes and butenes yield propene and butadiene, respectively. 1,1-Dichloro ethane or 1,1-dibromo propane only split off one HHal and form chloroethene or 1-bromopropene-2. HCl elimination from 2-methyl propionic acid chloride, expectedly, produces dimethyl ketene. Most interesting, however, is the ring opening of monobromo cyclobutane to 1-bromo-butene-3, observed already at room temperature, which strongly suggests the intermediate formation of a chemisorbed surface carbene at Raney nickel. The formation of hexadiene-1,5 as a by-product in the HCl elimination of 1-chloropropane, i. e. a surface carbene dimer, indicates their presence also in other dehydrohalogenations heterogeneously catalyzed by Raney nickel.
Raney nickel, a highly reactive and air-sensitive solid, if prepared and investigated under oxygen-free conditions, exhibits interesting catalytic properties. Using photoelectron spectroscopy for real-time gas analysis in a flow reactor, the following results are obtained with alkyl and acylhalides: Dehydrohalogenation temperatures are lowered relative to thermal HHal elimination up to 350 K. Monochloro and bromo propanes and butenes yield propene and butadiene, respectively. 1,1-Dichloro ethane or 1,1-dibromo propane only split off one HHal and form chloroethene or l-brom opropene-2. HCl elim ination from 2-methyl propionic acid chloride, expectedly, produces dimethyl ketene. Most interesting, how ever, is the ring opening of monobromo cyclobutane to 1-brom o-butene-3, observed already at room temperature, which strongly suggests the intermediate formation of a chem isorbed surface carbene at Raney nickel. The formation of hexadiene-1,5 as a by-product in the HCl elim ination of 1-chloropropane, i.e. a surface carbene dimer, indicates their presence also in other dehydrohalogenations heterogeneously catalyzed by Raney nickel.
Conditions for ENDOR measurem ents of organosulfur radical cations are discussed and tested. The one electron oxidation of a variety of aromatic sulfur com pounds comprising benzene-1,2-dithiole, 1,4-dithiine, thianthrene and diphenylsulfide derivatives as well as 33S isotope-marked bis(2,5-dimethoxyphenyl)disulfide is accomplished using the oxygen-free, powerful and selective AlCl3/H2CCl2 reagent. Partly with substantial structural changes, paramagnetic M⊕ species of 1,2-benzodithiete, 1,4-dithiine, thianthrene and diphenyl sulfide result. Their temperature-dependent ENDOR signal patterns provide numerous information e.g. on radical cation structure and dynamics, on the rather high sulfur spin populations or on the spin rotation interaction dominated relaxation behaviour. Accordingly, to obtain optimum ENDOR effects in organosulfur radical cations low temperature measurements are required, and especially for still undiscovered 33S ENDOR couplings, small g factor anisotropies and 33S spin densities appear to be necessary.
By analyzing the phase diagrams of some trimethylhalogenosilane/pyridine- and methyl-trichlorosilane/lutidine-systems the existence of the incongruently melting addition compounds Me3SiF · (Pyridine)2, Me3SiCl · (Pyridine)2, MeSiCl3, · (2.5-Lutidine)2, MeSiCl3, · (2.6-Lutidine)2, (MeSiCl3)2 · 3.5-Lutidine, and the congruently melting compounds MeSiCl3 · 2.4-Lutidine, MeSiCl3 · (3.5-Lutidine)2 was proven.
Phase equilibrium studies of the Lewis acid-base systems AlCl3/PyHBr and AlBr3/PyHI indicate the existence of congruently melting compounds of the molar ratios 1:1 and 2:3.
These results are quite different from those of our studies of the AlCl3/PyHCl and the AlBr3/PyHBr systems, in which four compounds in the molar ratios 1:1, 1:2, 1:3, and 2:3 could be detected.
The melting point of pyridinium iodide observed at 284,8 °C (decomp.) differs from the previously reported one.