Showing papers by "University of Würzburg published in 1978"

A generalized formulation of dual radiation action.

Abstract: Dual radiation action is a process in which cellular lesions are produced as a result of the interaction of pairs of sublesions that are molecular alterations produced by ionizing radiation. Previous formulations of this process have employed a number of simplifying assumptions that limit the accuracy and the range of application of theoretical analysis. The formulation presented here removes some of these restrictions by introducing three functions that describe the geometry of the sensitive material in the cell, the geometry of the pattern of energy deposition, and the interaction probability of sublesions as a function of their separation. The relation derived is similar to that obtained previously, in that lesion production is found to depend on two terms that are proportional to the first and the second power of the absorbed dose. However, the coefficients of these terms are now derived on the basis of a more realistic treatment.

Multistage Organic Redox Systems—A General Structural Principle

Abstract: A general structural principle for organic compounds that have the capacity for two-stage electron transfer is based on the following reaction sequence: In this scheme one or both of the entities X may be replaced by Y⊖. The radical partners in these systems often have very high thermodynamic stability. The choice of the end groups X and Y, (partial) inclusion of n-systems in rings, alteration of the number of vinylene groups, and aza-substitution make many variations possible. By means of this general structural principle numerous known compounds are brought together and new redox systems are simultaneously set up. The aim of the present review is to demonstrate the broad applicability of this principle, to indicate its significance for science and industry, and to describe some reactions.

Optomotor-blindH31—aDrosophila mutant of the lobula plate giant neurons

Abstract: In theDrosophila mutantoptomotorblindH31 (ombH31), previously isolated for its defects in the optomotor turning response, the visual giant neurons of the lobula plate are missing or significantly reduced. In particular, fibres homologous to the H-and V-cells ofCalliphora as well as two fibres (M-cells) in the middle plane of the plate are affected.

Mehrstufige organische Redoxysteme — ein allgemeines Strukturprinzip

Abstract: Ein allgemeines Strukturprinzip fur organische Verbindungen, die zur zweistufigen Elektronenubertragung befahigt sind, geht aus der folgenden Reaktionssequenz hervor: Dabei konnen ein oder beide X durch Y⊖ ersetzt sein. In diesen Systemen besitzt der radikalische Partner oft sehr grose thermodynamische Stabilitat. Wahl der Endgruppen X und Y, (teilweiser) Einbau des π-Systems in Ringe, Veranderung der Zahl der Vinylengruppen sowie Azasubstitution ermoglichen vielfaltige Variationen. Durch dieses allgemeine Strukturprinzip lassen sich zahlreiche bekannte Verbindungen zusammenfassen und zugleich neue Redoxsysteme entwerfen. Die vorliegende Ubersicht will seinen breiten Gultigkeitsbereich demonstrieren, auf seine Bedeutung fur Wissenschaft und Technik hinweisen und einige Reaktionen beschreiben.

Corona virus induced subacute demyelinating encephalomyelitis in rats: a morphological analysis.

Abstract: Thirty percent of weanling rats infected with JHM murine corona virus developed a subacute demyelinating encephalomyelitis approximately 3 weeks after intracerebral inoculation Small demyelinating foci were located in the deep cerebral white matter and large, sharply demarcated demyelinating lesions were detectabll preserved in the demyelinating plaques in areas where the lesions extended to the gray matter Perivascular cuffings, consisting of plasma cells and mononuclear cells, were frequently found Viral antigen was found mostly in the white matter and in glial cells, leaving neurons unstained Electron microscopic studies of the early lesions of white matter disclosed two different kinds of cell degeneration which developed prior to the myelin disruption and mononuclear cell infiltration One was a small pyknotic cell, which is thought to be an oligodendrocyte and the other is a ballooned cell containing abundant microtubules Virus particles could be demonstrated only in the latter cell type Discussion about astrocytes as well as oligodendrocytes was made in relation to the initial stage of demyelination caused by virus infection This animal model may be useful in the analysis of the mechanisms leading to demyelination in subacute or chronic infections

Potassium Uniport and ATP Synthesis in Halobacterium halobium

Abstract: Light-driven potassium ion uptake in Halobacterium halobium is mediated by bacteriorhodopsin. This uptake is charge-balanced by sodium ions and not by proton release. Light-induced shifts in concentrations of divalent cations were found to be negligible. The transient changes in extracellular pH (alkaline overshoot) can be understood by the concomitant processes of ATP synthesis, proton/sodium exchange and potassium uptake. The driving force of potassium ion uptake is the membrane potential, no ATP-dependent potassium transport process is found. Fluorescence measurements indicate a high permeability of the membrane to potassium ions compared to sodium ions. Therefore the potassium ion diffusion potential contributes to the membrane potential (about 30 mV/decade) and thereby influences the ATP level. Sudden enhancement of the diffusion potential by the potassium ionophore monactin leads to the expected transient increase in cellular ATP level. Due to the large size (up to 100-fold) of the potassium ion gradient and its high capacity (intracellular concentration up to 3 M) the potassium ion gradient can well serve the cell as a long term storage form of energy.

Recombinant plasmids capable to replication in B. subtilis and E. coli

Abstract: The plasmid pBC16 (4.25 kbases), originally isolated from Bacillus cereus, determines tetracycline resistance and can be transformed into competent cells of B. subtilis. A miniplasmid of pBC16 (pBC16-1), 2,7 kb) which has lost an EcoRI fragment of pBC16 retains the replication functions and the tetracycline resistance. This plasmid which carries only one EcoRI site has been joined in vitro to pBS1, a cryptic plasmid previously isolated from B. subtilis and shown to carry also a single EcoRI site (Bernhard et al., 1978). The recombinant plasmid is unstable and dissociates into the plasmid pBS161 (8.2 kb) and the smaller plasmid pBS162 (2.1 kb). Plasmid pBS161 retains the tetracycline resistance. It possesses a single EcoRI site and 6 HindIII sites. The largest HindIII fragment of pBS161 carries the tetracycline resistance gene and the replication function. After circularization in vitro of this fragment a new plasmid, pBS161-1 is generated, which can be used as a HindIII and EcoRI cloning vector in Bacillus subtilis.

Isolation and characterization of the minimal fragment required for autonomous replication ("basic replicon") of a copy mutant (pKN102) of the antibiotic resistance factor R1.

Abstract: The mini plasmids deriving from pKN102, a copy mutant of the antibiotic resistance factor R1drd-19 of E. coli, share a common DNA sequence of 2.6 kb, which carries the minimal functions for autonomous replication. By cloning of two PstI fragments of this region it could be demonstrated that the “basic replicon” is a DNA segment not larger than 1.8 kb, which carries the origin of replication and the genetic information for at least two proteins. Protein F (MW=11.000 dalton) seems to be synthesed in larger amounts in minicells of E. coli than protein C (20.000 dalton). Plasmids containing this isolated replicon of R1 are completely compatible with the parental plasmid R1drd-19.

Studies on the activity of the renin-angiotensin-aldosterone system (RAAS) in patients with cirrhosis of the liver.

Abstract: Plasma renin activity (PRA), plasma renin concentration (PRC), angiotensinogen, angiotensin II (AT II) and plasma aldosterone were determined by radioimmunoassay in 77 patients with cirrhosis of the liver [group I: with ascites, untreated (n=23); group II: patients with ascites during treatment (n=32); group III: after removal of fluids, but under further spironolactone therapy (n=10); group IV: untreated subjects without ascites (n=12)]. With the exception of decreased angiotensinogen values in all groups ranging between 39% (group IV) and 73% (group III) no significant changes of the other parameters of the RAAS were found in untreated patients. A highly significant increase of PRA, PRC, AT II and plasma aldosterone was observed in treated cirrhotics with (group II) or without (group III) ascites. In the total series of patients AT II was closely related to PRA, PRC and aldosterone emphasizing aldosterone secretion. Plasma sodium was inversely correlated to PRA, PRC, AT II and aldosterone, but no relationship was detected between these parameters of the RAAS and plasma potassium. Our results indicate that hyperaldosteronism in cirrhosis appears unlikely to be the major determinant of avid renal sodium retention and ascites formation. An increased activity of the RAAS is most often initiated by therapeutic factors and/or markedly altered electrolyte metabolism. Therefore, basal conditions of the patients to be studied must be well defined to exclude any artificially induced stimulation of the RAAS.

Site specific recombination involved in the generation of small plasmids.

Abstract: The physical structures of seven small plasmids, Rsc10, Rsc11, Rsc12, Rsc13, Rsc15, Rsc10-1 and pEM1 were analyzed. Molecular lengths of these plasmids were determined to range from 7.65 to 19.8 kilobases or kb. Electron microscope heteroduplex analysis of these plasmids show that the plasmids were all derived from pKN102 (86.3kb) in a complicated process that takes place by a series of deletion and, in some cases, transposition events. Rsc10 and Rsc11 were each formed by a simple deletion event from the parental plasmid. The physical structures of Rsc13 and pEM1 suggest that these plasmids must have been derived by a single and two successive deletion events from Rsc11. In the formation of these plasmids, all the deletions occured at the ends of the transposon, Tn3, which confers ampicillin resistance (amp) to the plasmid, or at the ends of the insertion sequence, IS1. Rsc15 was assumed to be formed in a two step process. The first step was a deletion event to form Rsc10-1 which occurs at one end of the IS1 present in pKN102. At first, the deletion event leaves out the ampicillin gene but in the second step Tn3 is transposed to the newly formed plasmid, Rsc10-1. Rsc12 is believed to have been formed in a similar fashion; first, a series of deletions and second, the transposition of Tn3.

The Precambrian–Cambrian boundary beds in Morocco (Preliminary Report)

Abstract: In the Anti-Atlas, trilobites occur below the zone of Fallotaspis tazemmourtensis of Hupe (1953) and even somewhat below the first archaeocyathids of the region. Most of them are opisthoparions (Hupetina gen.nov is described), and the olenellid Eofallotaspis gen.nov. probably is ancestral to Fallotaspis. The age is concluded not be younger than the lower Atdabanian of the Siberian platform. In the High Atlas, in the area called Ounein, a complete succession of trilobites from the low Lower Cambrian through the Middle Cambrian is being studied. The oldest trilobites encountered here are referred to the new genus Lemdadella. Correlation with the Anti-Atlas or other regions is uncertain.

Cadmium in Pilzen

Abstract: Der Cadmiumgehalt von 402 Arten (1049 Proben) wildgewachsener Pilze lag zwischen < 0,1 and 120 mg/kg Trockengewicht, entsprechend < 0,01 and 10,8 mg/kg Frischpilz. Cadmiumarme Proben ilberwogen: 68% enthielten < 2 mg/kg Trockengewicht, 86,5% < 5 mg/kg Trockengewicht, entsprechend ca. < 0,2 and < 0,5 mg/kg Frischpilz. Der Cadmiumgehalt war eindeutig species- and auch gattungsabhangig. Proben mit mehr als 10 mg/kg Trockengewicht kamen bei 41 Arten vor, darunter 9Tricholomataceae, 10Agaricaceae, 11Cortinariaceae, 3Amanita-und 4Russula-Arten. Proben mit mehr als 50 mg/kg Trockengewicht kamen vor beiAgaricus augustus, A. perrarus, A. silvicola, A. macrosporus, A. maleolens undInocybe bongardii. Im einzelnen Fruchtkorper war der Cadmiumgehalt am niedersten im Stiel, am hochsten in den Lamellen bzw. der Rohrenschicht. Lamellen enthielten maximal 5mal so viel Cadmium wie das Hutfleisch. Bei cadmiumreichen Pilzen bestand eine erhebliche Anreicherung gegenuber dem Boden.

Structural differences in the mesentery microcirculation between normotensive and spontaneously hypertensive rats

Abstract: The mesentery preparation of normotensive rats (NR) (Pcarotis97±4 mm Hg) and of spontaneously hypertensive rats (SHR) (161±2 mm Hg) of comparable age (20±3 weeks) was used to study morphological changes of the microvasculature in established hypertension. The arterioles, classified according to their branching order, had an increased inner diameter in SHR (by 20%). The smooth muscle hypertrophy decreased with smaller vessel size. Pre- and postcapillary vessels were shorter in SHR than in NR by 17 to 35%. The number of these vessels related to the number of the feeding terminal arterioles was found to be reduced by nearly 50% in SHR. The data suggest a lowered arteriolar flow resistance in individual vessels of the hypertensive group concomitant with a gradually disappearing smooth muscle hypertrophy towards the capillary bed. The elevation of the resistance to blood flow in the hypertensive rats is obviously caused by a reduced number of resistance vessels, as seen in the mesentery vascular bed. Similar results were obtained in the true capillaries, which showed greater inner diameters (SHR vs NR: 7.2 μm vs 6.4 μm), shortened lengths (141 vs 170 μm) and a reduced number (50 bs 70). Red cell velocity in true capillaries did not differ (0.51 mm/s vs 0.49 mm/s). Arterio-venous shunt vessels were described with an average inner diameter of 11 μm. In SHR these vessels were shorter (424 vs 654 μm) and increased in number. The ‘hydraulic hindranc“ of AV-shunt vessels and true capillaries together was decreased in SHR; the surface area did not differ between SHR (55.7 · 103 μm2) and NR (50.1 · 103 μm2) suggesting no major variation in the exchange functions.

Further studies on the extraneuronal uptake and metabolism of isoprenaline in the perfused rat heart.

Abstract: To simultaneously determine the kinetics of removal, O-methylation and accumulation of 3H-isoprenaline, isolated rat hearts were perfused for 4 min with various concentrations of 3H-isoprenaline. The apparent K m for the O-methylation of 3H-isoprenaline (3.3±0.5 μM) was more than one order of magnitude lower than the corresponding value for the accumulation of unchanged amine (71.3±7.1 μM). The apparent K m for removal was very similar to that for accumulation (63.2±5.9 μM). At perfusion concentrations higher than 25 μM, i.e. when O-methylation was saturated, removal virtually equalled accumulation. However, at low substrate concentrations removal of 3H-isoprenaline was overwhelmingly followed by O-methylation; this led to a marked difference between rates of removal and those of accumulation.

The neuronal and extraneuronal uptake and metabolism of 3H-(−)-noradrenaline in the perfused rat heart

Abstract: 1. Hearts were obtained from reserpine-pretreated rats and perfused with 0.95 μM 3H-(−)-noradrenaline. The rate of removal of 3H-noradrenaline from the perfusion fluid was measured (from the arterio-venous difference) as well as the rate at which the 3H-metabolites appeared in the venous effluent. 2. When either 30 μM cocaine or 87 μM corticosterone was added under steady-state conditions during perfusion with 3H-noradrenaline (to inhibit neuronal and extraneuronal uptake, respectively), each inhibitor reduced the removal of noradrenaline by about 50%; in the presence of both inhibitors removal was abolished. 3. Dihydroxymandelic acid (DOMA) was of neuronal, normetanephrine (NMN) of extraneuronal origin; dihydroxyphenylglycol (DOPEG) and the OMDA fraction (containing methoxyhydroxyphenylglycol-MOPEG-and methoxyhydroxymandelic acid-VMA) were formed both neuronally and extraneuronally. 4. The extraneuronal metabolism of 3H-noradrenaline was in quick equilibrium with the 3H-noradrenaline in the perfusion fluid; most of the total formation of DOPEG, MOPEG and NMN was recovered from the venous effluent. 5. Extraneuronally formed DOPEG, MOPEG and NMN distributed in the tissue with half times corresponding to their half time for efflux. 6. Inhibition of monoamine oxidase (MAO) by pargyline increased the extraneuronal formation of NMN; MAO and catechol-O-methyl transferase (COMT) appear to be contained in the same extraneuronal compartment. 7. The extraneuronal accumulation of 3H-noradrenaline required 30 min or more to reach a steady state; inhibition of one or both enzymes slowed this process. Inhibition of MAO increased the extraneuronal accumulation of 3H-noradrenaline; inhibition of COMT failed to do so, since the enzyme inhibitor (U-0521) was a weak inhibitor of extraneuronal uptake. 8. The rate constants for the efflux of the metabolites of noradrenaline decreased in the order of MOPEG>DOPEG>NMN>DOMA>VMA.

[Modified technique in transsphenoidal operations of pituitary adenomas. Technical note (author's transl)].

Abstract: Bei transnasal durchgefuhrten mikrochirurgischen Operationen von Hypophysentumoren last sich durch die zusatzliche Anwendung von lumbaler Uberdruckluftfullung und endoskopischer Operationstechnik und -kontrolle eine weitere Verbesserung der Operationsergebnisse sowie eine Erweiterung der Indikationen fur den nasalen Zugangsweg erreichen. Die sitzende Lagerung des Patienten mit achsengerechtem Zugangsweg zur Sella turcica schafft, wie oben angefuhrt, die Voraussetzungen zum Einsatz dieser erganzenden Methoden. Durch die lumbale Luftinsufflation unter Uberdruck lassen sich auch sehr grose Hypophysentumoren haufig so in das vorgegebene Operationsfeld verlagern, das eine vollstandige Operation vom transnasalen Zugang aus moglich ist. Diese Moglichkeit wird durch den Einsatz der operativen Technik unter endoskopischer Kontrolle noch erweitert; letztere tragt auch wesentlich zur vollstandigen Tumorentfernung, insbesondere bei endokrin aktiven Tumoren, bei.

Molecular mechanism of 1,1-dichloroethylene toxicity: excreted metabolites reveal different pathways of reactive intermediates

Abstract: The excretion and biotransformation of [14C] 1,1-dichloroethylene (vinylidene chloride, VDC) after administration of a single oral dose has been investigated in female rats. Seventy-two hours after a dose of 0.5, 5.0, and 50.0 mg/kg, 1.26, 9.70, 16.47%, respectively, are exhaled as unchanged VDC, and 13.64, 11.35, 6.13% as 14CO2. The main pathway of elimination is through renal excretion with 43.55, 53.88, 42.11% of the administered radioactivity. Through the biliary system, 15.74, 14.54, 7.65% of the activity are eliminated. The isolation of the main metabolites of VDC from 24 h urine is accomplished through the combined application of solvent extraction, ion exchange chromatography and thin layer chromatography. Then gas chromatography and mass spectrometry are used for their identification. Three metabolites have been identified: thiodiglycolic acid, N-acetyl-S-(2-carboxymethyl)cysteine and methyl-thio-acetylaminoethanol. In addition, three smaller unidentified radioactive peaks have been found. Thiodiglycolic acid is the main metabolite in VDC metabolism. The simultaneous formation of an ethanolamine- and a cysteine-conjugation product points to different reaction pathways of the postulated intermediate reactive epoxide; ethanolamine probably originates from membrane lipids, which react with VDC-epoxide and/or its derivatives. This pathway could explain, in part, the parenchyma damaging effect of VDC.

The kinetic constants for the extraneuronal uptake and metabolism of 3H-(-)-noradrenaline in the perfused rat heart.

Abstract: 1. Rat hearts were perfused with 50–2000 μM 3H-(−)-noradrenaline in the presence of 14C-sorbitol (to measure the extracellular distribution of the amine) and of 100 μM cocaine (to inhibit neuronal uptake). Initial rates of removal of noradrenaline were determined. Extraneuronal uptake determined in this way consisted of two components: a saturable and a non-saturable one. 2. When monoamine oxidase (MAO) was inhibited, the kinetic constants for saturable extraneuronal uptake of noradrenaline were: Km 60 μM, Vmax 50 nmoles · g−1 · min−1. U-0521, an inhibitor of catechol-O-methyl transferase (COMT) acted like a competitive inhibitor of extraneuronal uptake: the Km increased, Vmax remained unaffected. 3. In separate experiments either MAO or COMT was intact. Rat hearts were perfused with various concentrations of 3H-(−)-noradrenaline until the metabolites appeared at a constant rate in the venous effluent. These steady-state rates of metabolite formation were used to determine the kinetic parameters of the metabolizing systems. 4. O-methylation of noradrenaline in the intact heart was a saturable process and obeyed Michaelis-Menten kinetics; it had very low Km (1.7 μM) and Vmax (1.2 nmoles · g−1 · min−1). 5. Also the deamination of noradrenaline by the perfused heart was a saturable process, but Km and Vmax were considerably higher than for O-methylation (140 μM and 25 nmoles · g−1 · min−1, respectively). 6. It is concluded that “extraneuronal uptake and subsequent metabolism” of noradrenaline represents a site of loss that is highly effective at very low substrate concentrations (i.e., below the Km of the two metabolizing systems).

Restriction map of the antibiotic resistance plasmid R1drd-19 and its derivatives pKN102 (R1drd-19B2) and R1drd-16 for the enzymes BamHI, HindIII, EcoRI and SalI

Abstract: The conjugative R plasmid R1drd-19, mediating antibiotic resistance to ampicillin (Ap), chloramphenicol (Cm), kanamycin (Km), streptomycin (Sm) and sulfonamides (Su) was mapped using the restriction endonucleases BamHI, HindIII, EcoRI and SalI. BamHI generates 5 fragments (A-E) with molecular weights between 46×106 dalton (representing mainly the RTF) and 0.25×106 dalton, and HindIII 8 (A-H) between 42×106 dalton (representing the main part of the RTF) and 0.1×106 dalton. EcoRI recognises 17 sites and produces fragments (A-Q) with molecular weights between 11.7 and 0.1×106 dalton. SalI yields 7 fragments (A-G) of 16.5 to 2.0×106 dalton. A physical map was constructed from fragments obtained by partial digestion of R1drd-19 with one restriction enzyme, by double and triple digestion of the DNA with two or three enzymes with and without isolation of individual bands from preparative gels. In addition the restriction patterns of several mutants of R1drd-19 were compared with it. Evidence is presented which indicates that the derivatives of R1 investigated are generated by extende deletions, namely the copy mutant pKN102 which has lost the Km resistance, R1 drd-16, which has lost all resistances other than Km and the Kms derivative of R1drd-16, which represents the pure RTF. The map of R1drd-19 is remarkably different from those of R100 and R6-5. Its molecular weight was estimated to be 62.5 Md. The circular fragment order for BamHI is: A-C-B-D-E, for HindIII: A-D-C-B-F-H-E-G, for EcoRI: A-C-K-B-F-J-O-D-H-L-G-P-Q-N-I-E-M-and for SalI A-B-C-D-G-F-E.

The ultrastructure of the developing neural lobe.

Abstract: The ultrastructure of the developing neural lobe of rats was studied. The results revealed three periods in its development. The first period lasts till the 17th day of fetal life. At its beginning the anlage of the neural lobe is formed as a mass of cells very similar in appearance and in connection with the subependymal cells of the future median eminence. During the first period the cells of the anlage differentiate into pituicytes, and the penetration of the first nerve fibres and blood vessels among them is seen. The second period is from the 18th day of fetal life till one month after birth. At its beginning the first signs of neurosecretory activity were detected. During the period increasing numbers of neurosecretory fibres penetrate into the neural lobe, and the pituicytes show morphological signs characteristic of active cells. An increase in the functional activity of the neural lobe is also detected. The third period is from the end of the 1st till the end of the third month. During this period the development of the neural lobe proceeds and at the end it has the appearance of the adult gland. During this period the pituicytes gradually lose the signs of activity and at the end of the period they look like those observed in adult animals. Considering the results from the study, together with some data from previous investigations it is suggested that the pituicytes exert some stimulating and regulative influences on the process of neurosecretion in the neural lobe.

Detection of HBeAg and anti-HBe in acute hepatitis B by a sensitive radioimmunoassay.

Abstract: A solid-phase radioimmunoassay using anti-HBe-coated polysterence beads and iodine-125-labeled anti-HBe of human origin was developed for the detection of HBeAg. Anti-HBe could be determined by a blocking test. Both assays were about 500-fold more sensitive than immunodiffusion. Few nonspecific positive results for HBeAg could be recognized in the anti-HBe test by increase in cpm over that of the negative control. HBeAg was not found in acute hepatitis A and non A-non B hepatitis or in a control group of accident patients. On admission to the hospital 12 of 48 (25%) acute hepatitis B patients from Greece and 17 of 20 (85%) acute hepatitis B patients from Germany were HBeAg-positive. All 39 initially HBeAg negative sera were already anti-HBe positive. Tests of the acute stage and follow-up sera of the 20 German patients indicated that HBeAg is regularly present in the incubation period and early acute phase of hepatitis B. After onset of disease the antigen is cleared from the serum very rapidly in uncomplicated cases and is usually followed by the appearance of anti-HBe. Like anti-HBc, anti-HBe can serve as a tool for the diagnosis of hepatitis B after the disappearance of HBsAg.

Cyclophane, 6: Neue [2.2]Paracyclophane durch Addition von Acetylenderivaten an 1,2,4,5‐Hexatetraen

Abstract: Die tetrasubstituierten [2.2]Paracyclophane 4c–f werden durch Cycloaddition der symmetrischen Acetylenderivate 1c–f an 1,2,4,5-Hexatetraen (2) dargestellt und ihre Konstitution sowie Konfiguration durch spektroskopische Methoden, Abbau- und Pyrolyseexperimente bewiesen. An den Methylengruppen der Estersubstituenten von 4b, e und f last sich eindrucksvoll die Auswirkung diastereotoper Liganden auf NMR-Spektren demonstrieren. Die Anlagerung von Propiolsaure-ethylester (1h) an 2 liefert die disubstituierten [2.2]Paracyclophane 12a–d (R′ CO2C2H5), die nur durch Hochdruckchromatographie getrennt werden konnten, wahrend Cyanacetylen (1i) und 2 bevorzugt 12a und b (R′ CN) ergeben. Weitere symmetrische und unsymmetrische Acetylene reagieren nicht mit 2. Mehrere Wege zu dem Bisanhydrid 5 werden beschrieben, das seinerseits als Ausgangsmaterial zur Darstellung der Bisimide 13a–c sowie des Anthrachinonophans 15 dient. Cyclophanes, 6: New [2.2]Paracyclophanes by Addition of Acetylene Derivatives to 1,2,4,5-Hexatetraene The tetrasubstituted [2.2]paracyclophanes 4c–f are formed by cycloaddition of the symmetrical acetylene derivatives 1c–f to 1,2,4,5-hexatetraene (2), and their constitution and configuration is established by spectroscopic methods, degradation, and pyrolysis experiments. The methylene protons of the ester groups in 4b, e, and f demonstrate impressively the influence of diastereotopic ligands on NMR spectra. Addition of ethyl propiolate (1h) to 2 provides the disubstituted [2.2]paracyclophanes 12a–d (R′ CO2C2H5) which could only be separated by high-pressure liquid chromatography, whereas cyanoacetylene (1i) and 2 form 12a and b (R′ CN) preferentially. Further symmetrical and asymmetrical acetylene derivatives do not react with 2. Several ways of preparing the bisanhydride 5 are described, which in turn is used as starting material for the synthesis of the bis-imides 13a–c as well as the anthraquinonophane 15.

Membrane proteins of subacute sclerosing panencephalitis and measles viruses.

Abstract: SUBACUTE sclerosing panencephalitis (SSPE) is a rare, slowly evolving disease of the central nervous system (CNS) which has been associated with measles virus infection. A measles-like virus (SSPE virus) has been isolated from SSPE brain and lymph node material. Also, patients with SSPE show a humoral hyperimmune reaction against measles virus. These findings implicate measles virus as a possible aetiologic agent in this disease; however, they do not explain the pathogenicity of SSPE1,2. Additional factors, either host or virus derived, must have a pathogenetic role, as rarity and rural prevalence of SSPE cannot be correlated to the ubiquitous measles virus infection2. Indeed, biological, ultra-structural and biochemical investigations3–5 have indicated minor differences between SSPE and measles virus strains. On the basis of these findings, we have analysed the mRNAs of these viruses from infected cells and compared the antigenic properties of membrane (M) proteins isolated from purified SSPE (leukoencephalitis (LEC) ) viruses with those of measles (Edmonston) viruses. The results presented here show differences among the M proteins as well as the pattern of mRNAs of these viruses. The findings allow differentiation between these viruses and indicate that SSPE viruses are related but not identical to measles virus.