Showing papers by "University of Bern published in 1968"
TL;DR: Evidence is presented for the argument that the classical alcohol dehydrogenase functions mainly, during fermentation and ADH-2 participates in formation of carbohydrates from ethanol as well as for the isolation and properties of mutants of S. cerevisiae deficient in one or more forms of alcohol dehydrogensase.
239 citations
TL;DR: The intrinsic acidity of surface silanol groups was determined by coulometric titration of silicagel at 25° in solutions of the constant ionic strength 0,1M consisting primarily of sodium perchlorate.
Abstract: The intrinsic acidity constant Kint. of surface silanol groups has been determined by coulometric titration of silicagel at 25° in solutions of the constant ionic strength 0,1M consisting primarily of sodium perchlorate. The experimental data are consistent with
232 citations
TL;DR: Rat lungs were fixed by perfusion of glutaraldehyde through the vascular bed and by electron microscopy the alveolar epithelium was found to be covered by a thin extracellular lining layer that represents the surfactant layer fixed and demonstrated in situ.
214 citations
TL;DR: In this paper, it was shown that the rate of oxidation of magnetite crystals smaller than about 0.2µ to γ-Fe2O3 is controlled by the diffusion of iron cations.
Abstract: X-ray diffraction and kinetic measurements show that the rate of oxidation of magnetite crystals smaller than about 0.2µ to γ-Fe2O3 is controlled by the diffusion of iron cations. A model of the mechanism is successful in describing the kinetics of the process.
207 citations
TL;DR: In this article, it was found that inorganic pyrophosphate markedly increased the time required for the transformation of amorphous calcium phosphate into its crystalline form under various conditions.
Abstract: The transformation of amorphous calcium phosphate into its crystalline form has been studiedin vitro under various conditions. The transformation was followed by changes in the pH and in the calcium and phosphate content of the solution and by changes in the Ca/P ratio and x-ray diffraction patterns of the solid phase. It was found that inorganic pyrophosphate markedly increased the time required for the transformation under the various conditions used. The addition of intestinal alkaline phosphatase abolished this retarding effect of pyrophosphate on the transformation. It is proposed that pyrophosphate may be one of the factors that allows part of the bone mineral to persist in a non-crystalline state. The alkaline phosphatase of bone, by virtue of its pyrophosphatase activity, might be able to accelerate the transformation processin vivo.
135 citations
TL;DR: A simple screening test was designed to detect atypical ADH in liver homogenates and a ratio QThiorlrca was determined, which represents the ratio between the activity in presence and in absence of this effector in the reaction mixture.
Abstract: In TABLE 1 some properties of the atypical enzyme are summarized and compared to those of normal ADH. The highest specific activity obtained for the atypical enzyme after a 200-fold purification is at least three to four times higher than that of normal ADH.2 Livers of carriers of the variant ADH show total activities about five times higher than normal livers, when determined in biopsy samples and at physiological pH and temperature. For all the liver specimens including those obtained by autopsy this difference is even larger (FIGURE 1). The normal pH-optimum for ethanol oxidation lies at pH 10.8. It is shifted to pH 8.5 for the atypical enzyme. These enzymes are also different regarding their sensitivity toward several effectors. Thiourea activates purified human alcohol dehydrogenase as i t does the isoenzymes of rhesus monkey and horse l i ~ e r . ~ , ~ The atypical enzyme on the other hand is inhibited, as is yeast ADH. o-Phenanthroline which chelates the zinc in the active center of human ADH2 inhibits the normal ADH more strongly than the atypical enzyme. A similar situation pertains to the inhibitors tribromethanol and 5-hydroxymethyl furfurol. These two compounds do not serve as substrates of either the normal or the atypical ADH. Pyrazol is a specific inhibitor of alcohol dehydrogenase, and is competitive with ethanol as ~ubs t r a t e .~ This inhibitor has a stronger action on atypical ADH than on the normal one. Characteristic differences are also found in the relative turnover rates of various alcohols. The normal enzyme oxidizes n-butanol, benzyl alcohol and cyclohexanol faster than does the variant ADH. Finally, no differences were detected for the Michaelis constants for ethanol, acetaldehyde and the coenzymes NAD and NADH2. Within the limits of the method, identical molecular weights were found for both enzymes by gel chromatography on a Sephadex G-200. A simple screening test was designed to detect atypical ADH in liver homogenates. According to the difference in the pH rate profiles (see FIGURE 2 ) the ratio of the activity at pH 10.8 to the one determined at 8.8 is greater than 1 for the normal enzyme and less than 1 for the atypical ADH. In addition to this QpH ( = Quotient pH), a ratio QThiorlrca was determined. It represents the ratio between the activity in presence and in absence of this effector in the reaction mixture. It is lower for atypical than for normal ADH. In order to include a parameter in the screening which is based on a difference in the turnover of some substrate, we searched for a substrate exerting some pharmacological activity. Recently, J. Raaflaub suggested that P-pyridyl carbinol (Ronicol) , a vasodilator, is oxidized to the corresponding aldehyde by alcohol dehydrogenase and finally to nicotinic acid.6 Working with human liver homog-
120 citations
TL;DR: It was shown that the concentration of most of the components of sweat vary with rate of sweating, and the course of the sodium and the chloride curve and the values of osmolarity in sweat favor the assumption that in cystic fibrosis of the pancreas, the precursor fluid is in the isotonic range.
Abstract: Sweat Composition in Relation to Rate of Sweating in Patients with Cystic Fibrosis of the Pancreas
99 citations
TL;DR: The release reaction caused by thrombin does not appear to be a non-specific extrusion process, or equivalent to lysosome activation, and its mechanism is discussed.
86 citations
TL;DR: In this article, a very similar fluorescence structure is obtained from the radiation of an ideally mode-locked laser and of a free-running laser with the same oscillating bandwith.
76 citations
TL;DR: In this paper, in vitro an 5 Rattenaorten die Wirkung einer „physiologischen“ Adrenalin-losung auf die endothelspezifische Organelle gepruft.
Abstract: Die Blutgefasendothelien der Wirbeltiere enthalten eine spezifische cytoplasmatische Organelle, der nach einer schon fruher geauserten Hypothese eine Funktion im Rahmen der Blutgerinnung zukommen konnte. Da Adrenalin fahig sein soll, aus der Aortenwand eine gerinnungsaktive Substanz freizusetzen, wurde in vitro an 5 Rattenaorten die Wirkung einer „physiologischen“ Adrenalinlosung auf die endothelspezifische Organelle gepruft. Als Kontrolle dienten direkt fixierte, sowie in Ringerlosung inkubierte Aortenringe des gleichen Tieres. Die durch die Inkubation hervorgerufenen morphologischen Veranderungen der Gefasintima werden beschrieben und besprochen.
70 citations
TL;DR: Catalase activity in blood, liver, and kidney of a mutant strain Csb has been found to be decreased as compared to the level in normal mice, however, the extent of the reduction largely depends on the conditions used for activity determination, in particular, temperature and duration of the incubation period.
Abstract: Catalase activity in blood, liver, and kidney of a mutant strain Csb has been found to be decreased as compared to the level in normal mice. However, the extent of the reduction largely depends on the conditions used for activity determination, in particular, temperature and duration of the incubation period. In liver, this effect is most pronounced, the observed activity in mutants varying between 21 and 85% of the normal level. This dependence on the assay conditions is mainly due to the unusual heat lability of the variant enzyme, which undergoes rapid inactivation when incubated at 37 C.
TL;DR: Lymphocystis virus obtained from bluegills was cultured in the permanent bluegill cell line BF-2 and examined in ultrathin sections of cell cultures and in negative-contrast preparations from cells and from centrifuged culture medium.
Abstract: Lymphocystis virus obtained from bluegills (Lepomis macrochirus) was cultured in the permanent bluegill cell line BF-2 and examined by electron microscopy in ultrathin sections of cell cultures and in negative-contrast preparations from cells and from centrifuged culture medium. According to negative-contrast preparations, the icosahedral virions have an overall diameter close to but not exceeding 300 mμ. Delicate filaments seem to issue from the vertices. In collapsed virions, an ordered array of morphological units was seen. Positively contrasted virions in ultrathin sections show a shell with three dark (heavy metal-stained) layers alternating with and separated by two clear layers. The acquisition of an additional outer membrane during release from the cell, as found in African swine fever virus, was never seen. Morphologically, lymphocystis virus is considered to be closely related to Tipula iridescent virus.
TL;DR: The findings are against an oxygen deficit as a cause of cardiac deterioration in shock, suggesting structural derangements possibly due to catecholamine effects or toxic substances of peripheral origin.
Abstract: Twelve experiments were performed on healthy, anesthetized dogs on constant ventilation. Blood pressure, acid-base status, oxygen supply and lactate/pyruvate metabolism were monitored in the blood. The activities of nine glycolytic enzymes were assayed in left ventricular myocardium. A presumably irreversible state of hemorrhagic shock was produced by the reservoir technique and its metabolic sequels recorded in the blood. The analysis of coronary sinus blood did not reveal an oxygen deficit of the heart. The majority of the enzymes assayed showed higher activities following shock. Exceptions were pyruvate kinase, LDH and α-HB-DH. Activity differences between sampling sites appeared following shock especially in the inner layer of the left ventricle. The pattern of transmural activity gradients previously found in the normal state was disturbed. The findings are against an oxygen deficit as a cause of cardiac deterioration in shock, suggesting structural derangements possibly due to catecholamine effects or toxic substances of peripheral origin.
TL;DR: U-Pb isotopic analyses for zircons of nine igneous rocks and high grade metamorphic paragneisses from the Silvretta nappe and the Gotthard massif, Switzerland are reported in this paper.
Abstract: U-Pb isotopic analyses are reported for zircons of nine igneous rocks and high grade metamorphic paragneisses from the Silvretta nappe and the Gotthard massif, Switzerland.
TL;DR: It is concluded that in cockroaches the gonadotropic hormone of the corpora allata is responsible for the synthesis and release into the haemolymph of proteins and possibly other nutrients as well as for the transport of these nutrients through the follicular epithelium into the oocytes.
TL;DR: The granules were found to appear only when tissue prefixed in glutaraldehyde is postfixed with osmium in phosphate buffer, and the possible significance of these granules is discussed.
TL;DR: In this article, the rate equations for the density of excited ions in noble gas discharges are solved for the steady state and conditions for maximum inversion density and power output are calculated and compared with experimentally determined values.
Abstract: Rate equations for the density of excited ions in noble gas discharges are solved for the steady state. The atomistic parameters in the theoretical treatment are replaced by experimental values. Hence inversion density and single pass gain can be calculated as a function of gas pressure, discharge current and geometry of the discharge tube. Conditions for maximum inversion density and power output are calculated and compared with experimentally determined values. The calculation is pointing out large bored tubes to be advantageous for high power operation. Numerical evaluations are particularily given for theA+ line 4880 AU.
TL;DR: In this paper, the 39 Ar-activity in atmospheric argon has been measured for the first time by comparison of recent Atmospheric argon with argon originating from 40 K-decay in well gas.
TL;DR: In this article, the primary minerals of a partly serpentinized Alpine type ultrabasic mass, lying in a zone of low Alpine metamorphism, were analyzed with an electron microprobe.
Abstract: The primary minerals of a partly serpentinized Alpine type ultrabasic mass, lying in a zone of low Alpine metamorphism, were analysed with an electron microprobe. The distribution coefficients of Mg and Fe in coexisting orthopyroxenes, clinopyroxenes and olivines indicates an equilibrium temperature of around 1400°C. The Ca/Ca+Mg ratios in the clinopyroxenes indicate temperatures between 800° and 1000°C. This discrepancy in temperature estimations can partly be explained by the high Al2O3-contents of the clinopyroxenes, since a good correlation between Al2O3-contents and Ca/Ca+Mg ratio was found. The Na2O-content of the clinopyroxenes decreases in the successive pyroxenites that differentiated from the main lherzolite. From the mineralogical composition of the different rock types and the chemical compositions of the minerals it is concluded that the Totalp peridotite originated in the Upper Mantle.
TL;DR: In this article, the crystal structures of Co3[Co(CN)6]2, 12 H2O (a, = 10.210 ± 0.005 A) and Cd3[C(CN), 12 H 2O(a = 0.590 ± 0., 0.95 A) have been determined by X-ray powder methods.
Abstract: The crystal structures of Co3[Co(CN)6]2, 12 H2O (a, = 10.210 ± 0.005 A) and Cd3[Co(CN)6]2, 12 H2O (a = 10.590 ± 0.005 A) have been determined by X-ray powder methods. According to the measured density the unit cell contains 1 1/3 formula units with 4 Co2+ (Cd2+) in 4a, 2 2/3 Co3+ in 4b, 16 C and 16 N in 24e, 8 H2OI near 24e, (96k) and 8 H2OII near 8 c (192 l). Structure factor calculations based on the space group Oh5 - F m 3 m lead to the following final values of the reliability index R: 0.038 (Co3[Co(CN)6]2, 12 H2O) and 0.037 (Cd3[Co(CN)6]2, 12 H2O). The interatomic distances for the cobaltous compound (in parentheses for the cadmium compound) are: Co3+-C: 1.88 A (1.89); C-N: 1.15 A (1.17); Co2+-N: 2.08 A (2.24); Co2+-OI: 2.10 A (2.27); shortest OI-H-OII-bonds: 2.89 A (2.82). Co3+ is octahedrally coordinated by six carbon atoms, the divalent metal ion by four nitrogen atoms and two water molecules. The two different metal ions are connected by M2+-N-C-Co3-bonds to a threedimensional network. The infrared and electronic spectra are shown to be in agreement with the results of the structure analyses of these compounds. The observed positions of the OH-stretching vibrations lead to a hydrogenbond-length of 2.8–2.95 A.
TL;DR: L Liver in vitro systems are described which allow the separate study of dem methylation and N-oxidation of IP, reduction and demethylation of IPNO, and sum of all four metabolic reactions.
TL;DR: An improved method for the bioassay is described; it consists essentially of a new quantitative evaluation of the behaviour of the termites, and the most active chemicals are n-caproic acid (n-hexanoic acid) and farnesol, which is not present in the natural pheromone.
TL;DR: A sensitive method for the determination of imipramine and seven of its major metabolites in biological samples is described, based on the partition properties which were determned for each metabolite.
TL;DR: In this paper, the solubilities of the ternary system Cu2+H2O-CO2(g), including CuO, Cu(OH), Cu2(OH)2CO3, Cu3(OH,2(CO3)2, Cu2+, and Cu (CO 3)22−, were studied at 25°C in solutions of the constant ionic strength 0,2 M consisting primarily of sodium perchlorate.
Abstract: The solubilities of Cu2(OH)2CO3 (malachite) and Cu3(OH)2(CO3)2 (azurite) have been studied at 25° C in solutions of the constant ionic strength 0,2 M consisting primarily of sodium perchlorate. From experimental data the following values for equilibrium constants and Gibbs energies of formation are deduced:
Predominance area diagrams for the ternary system Cu2+H2O-CO2(g), including CuO, Cu(OH)2, Cu2(OH)2CO3, Cu3(OH)2(CO3)2, Cu2+ and Cu (CO3)22−, are given.
TL;DR: It has been found that inZootermopsis nevadensis, a relatively primitive termite, the nymphs and older larvae carry out most nest-building behaviour, digging, and oscillatory movements and it is suggested that behavioural differences such as those found here may be important in caste determination and regulation.
Abstract: It has been found that inZootermopsis nevadensis, a relatively primitive termite, the nymphs and older larvae carry out most nest-building behaviour, digging, and oscillatory movements. As they progress from young larvae to nymphs the termites tend to spend less time in trophallaxis and more time in other activities. The first instar nymphs and the sixth instar larvae are the most active in all respects. In terms of behaviour the sixth instar larvae are the nearest equivalent to a worker caste. Insects of the first nymphal instar can be roughly divided into those that spend much time in trophallaxis and relatively little in other activities andvice versa. This polarity was not evident in the younger insects. The replacement reproductives spend most of their time in trophallaxis and very little in other activities. Most of this trophallaxis is with the younger larvae, while most of the trophallaxis of the other instars is with the replacement reproductives. It is suggested that behavioural differences such as those found here may be important in caste determination and regulation.
TL;DR: In this paper, the second-order coherence functions and the fluorescence traces were analyzed and described for two-photon pulse-width measurement and the shapes of the traces were found to be essentially the same for both, free-running and ideally mode-locked emission, but with different contrast ratios of 1.5 : 1 and 3 : 1, respectively.
Abstract: Two-photon fluorescence traces used for picosecond pulse-width measurement are analyzed and described by intensity correlation functions, also known as second-order coherence functions. The correlation functions and the fluorescence traces are discussed for three special types of light emission and calculated in detail for a three-mode laser model in free-running, mode-locking, and FM-like operation. A rigorous calculation for the fluorescence intensity excited by a laser oscillating in a large number of modes with arbitrary amplitudes and phases is also given. The shapes of the fluorescence traces are found to be essentially the same for both, free-running and ideally mode-locked emission, but with different contrast ratios of 1.5 : 1 and 3 : 1, respectively.
TL;DR: Second and third order correlation functions for an exponential pulse shape are discussed in this article, where it is shown that for a light pulse showing an asymmetric shape these correlation functions become asymmetric, too.
TL;DR: It is concluded from the results that the mode of administration highly influences both the rates of drug absorption and of its metabolism, the latter according to systematic (s.c., i.m.) or portal (i.p., p.o.) absorption.
TL;DR: The abundances and isotopic composition of lithium were determined in an achondrite and in separated chondrule and matrix fractions from one chondrite of each of the classes LL3, H3, L4 and L6 as mentioned in this paper.
TL;DR: In this article, the authors considered the product to possess an intergrowth structure of a Groutite matrix with statistically and layerwise distributed Manganite microdomains, according to a model proposed by DE WOLFF for α-MnO2.
Abstract: The reduction of γ-MnO2 with cinnamic alcohol in xylene at 90° leads (1) to γ-MnOOH in a double phase reaction with germination if the α-MnO2 is extremely disperse, and (2) to α-MnOOH in a strictly topotactical (single phase) reaction without germination if the γ-MnO2 is relatively well crystallised. The hexagonality of the densest packed oxygens is not a linear function of the reduction rate but shows a discontinuity when about half of the Mn4+ are reduced, which is consistent with results of GABANO. The αMnOOH obtained by this reaction shows still the selective and asymmetric X- ray and electron reflection broadening of the reactant. Hence, the authors consider the product to possess an intergrowth structure of a Groutite matrix with statistically and layerwise distributed Manganite microdomains, according to a model proposed by DE WOLFF for α-MnO2. The domains are supposed to have the size of one cell only in the b direction, and of a few cells in the a direction, and to be present in relatively small concentration.