Possible relationship between micronucleated and binucleated cells induced by cisplatin in cultured CHO cells

1993

Abstract Chinese hamster ovary (CHO) cells were treated with a single dose (10 μg/ml) of cis-diammino-dichloroplatinum (II) (cisplatin) for 1 h and the effect of the drug on the kinetics of proliferation of the cultures was studied. It was found that the drug produces a delay in the proliferation rates of the treated cultures. The induction of micronuclei and binucleated cells (BC) at different times after treatment have also been studied, and the ability of these cells to undergo DNA synthesis (measured as the ability to incorporate [3H]thymidine) is shown. It was found that cisplatin induced a particular type of BC that contains one or more micronuclei rather than a pure population of BC.…

Dynamics of Colloidal Hard Spheres in Thin Aqueous Suspension Layers—Particle Tracking by Digital Image Processing and Brownian Dynamics Computer Sim…

1993

Abstract A new experimentally simple technique is introduced for studying dynamical properties of hard sphere colloids in thin aqueous suspension layers by light-microscopy observation supported by computer-aided digital image processing. The thickness of the layers of the colloidal samples confined between two smooth glass plates is accurately adjusted by monodisperse "spacer" spheres which are larger than the diffusing spheres. Tracking of single particles in concentrated phases is accomplished using fluorescence light microscopy where a few dyed particles are mixed with the undyed colloidal spheres of the same size. First results are presented for the self-diffusion coefficient—(i) in ve…

Influence of cyclopropene fatty acids (Baobab seed oil) feeding on the in vitro Δ9 desaturation of stearic acid in rat liver microsomes

1993

Abstract Δ9 desaturation of [1−14C] stearic acid to oleic acid was studied in liver microsomes of rats fed either fresh Baobab seed oil, containing cyclopropene fatty acids (malvalic acid and sterculic acids), or heated Baobab oil, containing only minor amounts of these acids. This was compared with rats fed a control oil mixture or a fat-free diet. Up to 50 nmol of substrate, Δ9 desaturation rate was the same in rats fed the three fat diets. From 50 to 150 nmol, the desaturation rates were practically constant in rats fed fresh Baobab seed oil. It increased in heated oil-fed rats at the same rate as in the control group, but more slowly than in the fat-free diet group. Fatty acid compositi…

Massive neutrinos and right-handed weak currents in double beta decay.

1993

The contributions of right-handed weak currents in neutrinoless double beta decay are studied taking explicitly into account the mass corrections to the intermediate neutrino propagator. Due to these corrections the right-handed currents become effective even if all neutrinos are light ([ital m][sub [nu]][gt]10 MeV). Explicit expressions for the neutrino-momentum integrals and the decay half-life are derived. As an example two neutrino-mass scenarios containing the hypothetical 17-keV neutrino are discussed. The experimental half-life of the [sup 76]Ge[r arrow][sup 76]Se decay is used to obtain an upper limit for a new kind of effective right-handed coupling within the two scenarios.

Laser direct writing of gold conductors from metallorganic inks

1993

Laser deposition of gold lines from spin-on metallorganic (MO) precursors has been studied. A readily available and relatively low-cost commercial MO ink has been used to write gold interconnects on different substrates. The physical properties of the ink, its laser-firing process on oxidised silicon substrates and its electrical characterisation are presented here, together with the experimental procedure needed for obtaining low-resistivity deposits.

false

1993

Several zwitterionic polymers were prepared by radical homopolymerization of surfactant monomers which bear diallyl, diene or vinylcyclopropane moieties. These polymer systems were complemented by alternating copolymers of appropriate zwitterionic vinyl compounds. Thus, polymers with reduced (as compared with simple vinylic homopolymers, or statistical copolymers) and well defined density of surfactant side groups are obtained. The solubilities found for these polymers are dominated by polymer geometry rather than by the balance of hydrophilic and hydrophobic fragments, thus corroborating a “main-chain spacer” model proposed recently. All water-soluble polymers exhibit characteristic featur…

Molecular dynamics studies of 3D quasicrystals

1993

Abstract The thermodynamic behaviour of monatomic and diatomic models of three-dimensional icosahedral quasicrystals has been studied in NVT and NPT ensembles using molecular dynamics simulations with atoms interacting via Lennard-Jones potentials. We also report on a microcanonical MD simulation of decagonal Al 65 Cu 20 Co 15 quasicrystals where an experimentally determined binary model has been used. To obtain stability in this latter case it is necessary to endow the atoms with effective pair potentials. No transitions to crystalline or amorphous phases were found for diatomic models. Monatomic models, however, display a certain stability only in the low-temperature region. In the range …

Conversion electron Mössbauer study of low carbon steel polarized in aqueous sulfate and sulfite containing sulfate solutions

1993

Abstract The passivation of low carbon steel was studied in aqueous solutions of 0.5 M Na 2 SO 4 (pH = 3.5 and 6.5) and of 0.5 M Na 2 SO 4 + 0.001 M NaHSO 3 (pH 3.5 and 6.5). The used conversion electron Mossbauer spectroscopy (CEMS) with the complementary electrochemical, microscopic and spectrophotometric investigations proved that the presence of sulfite ion induces pitting corrosion. The compositions and thichnesses of the passive films formed during the electrochemical treatments are determined from the conversion electron Mossbauer spectra. γ-FeOOH was found in each case as a major component. At pH = 3.5, the sextet belonging to Fe 3 C appears in the spectra in most cases, and also Fe…

false

1993

The influence of lithium tert-butoxide (tBuOLi) and of lithium chloride on the oligomerization of tert-butyl acrylate (tBuA) initiated by tert-butyl α-lithioisobutyrate (tBiB-Li) was investigated. These additives affect both the kinetics and the product distribution. Whereas the addition of LiCl leads to a narrower molecular-weight distribution (MWD) the presence of tBuOLi induces broader MWD's, characterized by a very high fraction of the dimer. Both additives decrease the rates of propagation to different degrees. These effects are discussed on the basis of the formation of aggregates and adducts, the lithiated dimer having a higher tendency to form aggregates than the other oligomers. Th…

A question in the theory of saturated formations of finite soluble groups

1993

This paper examines the following question. If\(\mathcal{H}\) and\(\mathcal{F}\) are saturated formations then\(\mathcal{H}_\mathcal{F} \) is defined to be the class of all soluble groups whose\(\mathcal{H} - normalizers\) belong to\(\mathcal{F}\). In general\(\mathcal{H}_\mathcal{F} \) is a formation, but need not be a saturated formation. Here the smallest saturated formation containing\(\mathcal{H}_\mathcal{F} \) is studied.

Effect of the juvenile hormone analogue fenoxycarb applied via the host on the parasitoid Phanerotoma (Phanerortoma) ocularis Kohl (Hym. Braconidae)

1993

Abstract Concentrations of 0.001, 0.005, 0.01, 0.05 and 0.1 μg/ml of fenoxycarb (Ro 13-5223) were applied topically to larvae of Ephestia kuehniella Zeller parasitized by Phanerotoma (Phanerotoma) ocularis Kohl. The effect of the treatment and concentration on parasitism rates, preimaginal mortality and emergence rates of the parasitoid were studied comparatively for each larval instar of the host considered. The preimaginal mortality was high when the fenoxycarb was applied on the first larval instar of the host (23–46%) and more higher when applied to the sixth larval instar of the host (40–86%). Consequently, fenoxycarb treatment of the last larval instar of the host produced a reduction…

Investigation into the role of phosphodiesterase IV in bronchorelaxation, including studies with human bronchus.

1993

1. We have investigated the role of cyclic nucleotide phosphodiesterase IV (PDE IV) in the relaxation of human bronchus and guinea-pig trachea in vitro and in guinea-pigs in vivo. 2. Functional studies showed that the selective PDE IV inhibitors, rolipram and denbufylline, relaxed human and guinea-pig preparations in vitro. 3. Two clinically used xanthine non-selective PDE inhibitors, theophylline and pentoxifylline, were also effective in these preparations, but were much less potent than the selective agents used. 4. The rank order of potency for the four PDE inhibitors in both species was similar. 5. Biochemical studies indicated that PDE IV was the major PDE isoform present in the human…

Properties of Chemically Interesting Potential Energy Surfaces. (Reihe: Lecture Notes in Chemistry, Vol. 56.) VonD. Heidrich, W. Kliesch undW. Quapp.…

1993

Donnan phenomena in membranes with charge due to ion adsorption. Effects of the interaction between adsorbed charged groups

1993

A physical model for the modified Donnan phenomenon associated with ion adsorption on localized membrane sites is presented. This model accounts for the dependence of the concentration of adsorbed ions on electrolyte concentration and pH as it is influenced by the electrostatic interaction between adsorbed ions. The equilibrium thermodynamic concepts employed are based on the Donnan formalism for the ion equilibria between membrane and solution, and the Bragg–Williams approximation for an adsorption isotherm that incorported interaction between adsorbed ions. Our results include the concentration of charged groups in the membrane, the pH of the membrane phase solution, and the Donnan potent…

The Mainz pouch II (sigma rectum pouch).

1993

A low pressure rectosigmoid reservoir for urine is created obviating the need for colostomy, augmentation or extensive bowel surgery. Antimesenteric splitting of the intestine at the rectosigmoid junction and subsequent side-to-side anastomosis are performed. Urodynamic data demonstrate that the detubularization is effective in rendering high pressure bowel contractions ineffective. Without the risk of damaging the mesentery the pouch is fixed at the promontory, which lessens the risk of ureteral kinking and upper urinary tract dilatation. The technique is indicated not only in cases of failed ureterosigmoidostomy but also for primary urinary diversion. All 47 patients who underwent the ope…

Mise en evidence de la pheromone sexuelle chez les femelles de Blattella germanica L.

1993

L’existence d’une pheromone sexuelle femelle attractive a distance et produite par les glandes pygidiales chez B.germanica a ete demontree. L’ultrastructure de l’epithelium glandulaire a montre des cellules epldermiques banales et des cellules du canal associees a des cellules secretrices, formant les unites glandulaires de classe 3. Chez la jeune femelle vierge, la couche glandulaire est de faible epaisseur, elle augmente progressivement et atteint son maximun entre les 10eme et 13eme jours. Pendant la gestation, elle diminue considerablement puis reprend sa croissance apres le rejet de l’ootbeque. L’attraction des femelles de B. germanica est progressive, elle devient faible pendant la ge…

Morphometric Study of the Bone Marrow in Polycythemia Vera Following Interferon-Alpha Therapy

1993

Bone marrow cellularity and extent of fibrotic change were determined in nineteen patients with polycythemia vera, treated with interferon-alpha (IFN) for 1 year. The cellularity was evaluated with an interactive semiautomatic method using Leitz TAS plus microscope: in particular, number and size of megakaryocytes were evaluated after immunostaining with Y2/51 (CD 61); reticulin content was studied by light microscope with a semiquantitative method. Before IFN therapy mean cellularity was 80.5% (+/- 13.7). After 6 and 12 months mean cellularity was 75.4% and 68.4% respectively. Six months after cessation of IFN therapy the cellularity was 69.1%. A decrease of the number, density and morphom…

Microwave experiments on electromagnetic evanescent waves and tunneling effect

1993

A set of experiments is described to measure the decay of electromagnetic evanescent waves and the tunneling effect through an airgap. The experiments are performed using microwaves and have been designed to be carried out by third year students of physics. The proposed experimental setup can be regarded as a quantum mechanical simulator for the one‐dimensional motion of a particle.

Response of BGO detectors to photons of 3–50 MeV energy

1993

Abstract The response of an array of 7 hexagonal BGO detectors each 7.5 cm long (6.7 radiation lengths) with 3.6 cm side-to-side distance was measured using monochromatic photons from the tagged-photon facility at the electron accelerator MAMI A at Mainz. The experimental spectra of the deposited energy for a single detector and for the array of seven modules compare very well with the predictions of Monte Carlo shower simulations using the code GEANT3. Significant improvement of the energy resolution is observed for the summed energy spectra compared to the resolution of a single module. This improvement deteriorates at higher photon energies because the length of the detector is not suffi…

Effect of beta-N-oxalylamino-L-alanine on cerebellar cGMP level in vivo.

1993

Beta-N-oxalylamino-L-alanine (BOAA), a non-protein amino acid present in the seeds of Lathyrus Sativus (LS), is one of several neuroactive glutamate analogs reported to stimulate excitatory receptors and, in high concentrations, cause neuronal degeneration. In the present study, the in vivo acute effects of synthetic BOAA and LS seed extract were investigated on rat cerebellar cyclic GMP following intraperitoneal (10-100 mg/kg) or oral (100 mg/kg) administration of subconvulsive doses of toxin. Furthermore, the BOAA content in LS seeds and in the cerebellum of injected rats was determined by high performance liquid chromatograph analysis. A dose- and time-dependent increase of cerebellar cy…

Beta-adrenoceptor density and subtype distribution in cerebellum and hippocampus from patients with Alzheimer's disease

1993

beta-Adrenoceptor density and beta 1- and beta 2-subtype distribution were examined in hippocampi and cerebella from patients with Alzheimer's disease (AD/SDAT). Tissues from age-, sex and post-mortem delay matched non-demented patients served as controls. The total beta-adrenoceptor density as evaluated in saturation experiments with the hydrophilic radioligand [3H]CGP 12177 was higher in hippocampal (36-39 fmol/mg protein) than cerebellar tissues (20-21 fmol/mg), however, no differences were found in either brain region between AD/SDAT patients and controls. Subtype distribution using the highly selective beta 1-adrenoceptor antagonist CGP 20712A revealed a slightly higher proportion of b…

Effect of Salt-Loading and Spontaneous Hypertension on in Vitro Metabolism of [1-14C]Linoleic and [2-14C]Dihomo-γ-linolenic Acids

1993

The present study compared the effect of spontaneous hypertension and salt-loading on in vitro metabolism of 18:2n-6 (linoleic acid) and 20:3n-6 (dihomo-gamma-linolenic acid). Ten weanling spontaneously hypertensive rats (SHR) and 10 normotensive Wistar-Kyoto rats (WKY) maintained on a rodent lab chow were given tap water with (n = 5) or without (n = 5) addition of 1% NaCl for 4 weeks. Thereafter, animals were killed and liver microsomes were prepared. Aliquots of microsomes suspended in the phosphate-sucrose buffer containing MgCl2, ATP, CoA, and NADPH were incubated with 0.3 microCi of [1-14C]-18:2n-6 or [2-14C]-20:3n-6 at 37 degrees C for 15 min. The activity of delta 6- and delta 5-desa…

Influence of synthesis conditions on the morphology of Dodecasil 1H

1993

Abstract The synthesis of Dodecasil 1H was studied in the system SiO2/1-adamantylamin/NH3/water with the objective of controlling the particle size and the morphology of the crystals. Since nucleation occurs in a very early stage of the synthesis, the heating rate to the final temperature and/or holding points during heat up have a strong influence on both parameters. Crystals smaller than 150 μm could only be obtained by the use of seed crystals, which are completely consumed in the synthesis with subsequent new nucleation. Using seed crystals, the expensive template 1-adamantylamine can be substituted with cheaper reagents such as sodium dodecyl sulfate or trimethylethylammonium bromide a…

Tc-99m HMPAO Cerebral Scintigraphy A Reliable, Noninvaslve Method for Determination of Brain Death

1993

To determine the usefulness of cerebral blood flow imaging for the diagnosis of brain death, 4 female and 12 male patients, aged 19 to 69 years and suffering from various intracranial lesions, were studied. In addition to neurologic examination, electroencephalographic recording, and cerebral angiography, tomographic brain scintigraphy was performed using a SPECT system with a LEAP collimator after the intravenous administration of 555 MBq Tc-99m HMPAO. The radioisotopic scanning procedure revealed no intracranial perfusion in 14 of the 16 patients. Only minimal cerebellar blood flow was seen in one patient. In another, residual right-sided supratentorial flow was initially present but abse…

rRNA gene restriction patterns and biotypes of Shigella sonnei.

1993

SUMMARYShigella sonneiis a major agent of diarrhoeal disease in developed as well as in developing countries. Several phenotypic methods to define strain differences have been applied to this species ofShigellaincluding, more recently, analysis of extrachromosomal and chromosomal DNA.In this study, 432 endemic and epidemic strains isolated between 1975 and 1991 in Italy, France and Switzerland were submitted to rRNA gene restriction pattern analysis, after digestion of whole-cell DNA byHincII, and to concomitant biotyping.Thirteen ribotypes, HI to H13, and five biotypes, a, d, e, f, g, were detected. Xinety-five percent of the sporadic strains were assigned to ribotypes HI to H4, which coul…

Computertomographie nach extrakorporaler Stoßwellenlithotripsie (ESWL) der Nieren

1993

In 105 patients CT studies were done prospectively after renal ESWL with a second generation lithotripter. 33 (31%) of the patients had renal oedema (n = 8), renal (n = 20) or extrarenal (n = 31) bleeding. Three of the 23 patients who had a three year follow-up had chronic renal changes, 10 had renal stones. As blunt renal trauma can be the cause of renal hypertension a longterm follow-up is necessary in ESWL patients, particularly if there was renal bleeding after treatment. Further studies are needed to determine the exact risk of renal hypertension after ESWL.

Effect of the crystallization on the phase transitions IV ⇐ III and IV ⇐ II of ammonium nitrate

1993

Abstract The solid state phase transition path of ammonium nitrate is influenced by the manner of crystallization. Slow crystallization from water gives ideal crystals, which behaved differently from crystals prepared by rapid crystallization from the melt.

Talbot interferometry: a new geometry

1993

Abstract With the Talbot effect, planes are found where the Fresnel diffraction pattern, of a Ronchi ruling, exhibits zero visibility. These planes are exploited to propose a novel geometry for Talbot interferometry, which has high sensitivity. Experimental verifications are included.

Modified Donnan phenomena in polyaniline with poly(vinyl sulphonate) chains

1993

We develop a physical model, based on the modified Donnan phenomena ideas introduced previously by the authors, to describe the acid doping of the conducting polymer polyaniline. The theory is motivated by the experimental work of Asturias et al. [Ber. Bunsenges. Phys. Chem. 95, 1381 (1991)]. Good agreement between theory and experiment is found.

Maintenance of GSH content in primary astrocyte cultures under oxidative stress conditions.

1993

LeptonicCPasymmetries in flavor-changingH0decays

1993

Leptonic flavor-changing ${H}^{0}$ decays with branching ratios of the order of ${10}^{\ensuremath{-}5}$-${10}^{\ensuremath{-}6}$ may constitute an interesting framework when looking for large $\mathrm{CP}$-violating effects. We show that leptonic $\mathrm{CP}$ asymmetries of an intermediate ${H}^{0}$ boson can be fairly large in natural scenarios of the minimal standard model with right-handed neutrinos, at a level that may be probed at future ${H}^{0}$ factories.

Stability of Prussian Blue films on ITO electrodes: effect of different anions

1993

Abstract Transformation of insoluble newly deposited Prussian Blue (PB) into the soluble structure stabilizes the film and allows its total oxidation to Prussian Yellow. The stability of PB films in electrochemical processes in successive potential cycling experiments and under long-term chemical attack by an electrolyte depends not only on the cation that takes part but also on the nature of the anion present. In aqueous media, the sulphate ion clearly destabilizes the crystalline structure whereas the nitrate ion favours stabilization. Initial changes in the voltammograms recorded immediately after the spectroscopic tests have been detected in all media. During the immersion period water …

Temperature dependence of the static structure factor of ortho-terphenyl in the supercooled liquid regime close to the glass transition

1993

Abstract Studying the temperature dependence of the static structure factor of ortho-terphenyl from the liquid state down to the glass we find that the main peak of S ( Q ) is split into two maxima which behave quite differently. While the maximum at Q =1.4 A −1 is not much affected by the temperature variation the one at 1.9 A −1 is significantly enhanced. This effect is connected with a change of the short range order, i.e. of the intermolecular distances, but evolves continuously. Thus the dynamic anomalies that have been observed in this system around a characteristic temperature T c ≈290 K are not simply due to a discontinuous change in S ( Q ) but can be attributed to the existence of…

Inhibition of antidepressant demethylation and hydroxylation by fluvoxamine in depressed patients.

1993

Bidirectional drug interactions between fluvoxamine and classical antidepressants were studied in depressed patients. A column switching technique combined with high performance liquid chromatography (HPLC) enabled automated analyses of plasma for simultaneous determination of fluvoxamine, tricyclic and tetracyclic antidepressants and demethylated and major hydroxylated metabolites in a single HPLC run. The measurements revealed that fluvoxamine inhibited N-demethylation of imipramine, clomipramine, amitriptyline and maprotiline whereas interferences with hydroxylation reactions were restricted to aromatic 8-hydroxylation of clomipramine. In patients under fluvoxamine monotherapy before com…

Alkaloids from Rauwolfia serpentina cell cultures treated with ajmaline

1993

Abstract A group of new alkaloids, the raumaclines, and some related alkaloids were isolated from Rauwolfia serpentina cell suspensions fed with high levels of ajmaline; their structures were determined and syntheses developed providing an essential prerequisite to the further study of their biosynthesis at the enzymatic level.

Interaction of the mitochondrial membrane D-3-hydroxybutyrate dehydrogenase with fluorescent phospholipids

1993

Norbert Latruffe l ,I, Boubker Nasser ‘, Claude Morpain 3, Jiirgen Zirkel 4, Michael Seiter 4, Bernard Laude 3 and Wolfgang Trommer 4 ’ Laboratoire de Biobgie Mol&laire et Cellulaire, Universite’ de Bourgogne, Fact& des Sciences Mirande, BP 138, 21004 D@on Cedex (France) 2 Laboratoire de Biochimie &A CNRS 531) and 3 Laboratoire de Chimie Organique, Universite’ de Franche-Comte 25030 Besaqon Cedex (France) 4 Fachbereich Chemie, Universitiit Kaiserslautem, D 6750 Kaiserslautem (Germany)