Showing papers by "University of Basel published in 1976"
TL;DR: Results provide evidence that determination at the blastoderm stage is not yet disc-specific, and there is a decrease in clone size with developmental age indicating proliferation of the primordial disc cells which give rise to the adult cuticular structures.
268 citations
TL;DR: In this article, the formation of a so-called water/oil (W/O)-microemulsion (AOT/isooctane/water) was followed by light scattering and ultracentrifuge measurements.
Abstract: The formation of a so-called water/oil (W/O)-microemulsion (AOT/isooctane/water) was followed by light scattering and ultracentrifuge measurements. With increasing weighed-in water concentrations the microemulsion is stabilized by repeated aggregational processes of micelles containing water due to a decrease of the free interfacial enthalpy.
This process conforms very satisfactorily to a model describing an adsorption of surfactants at the water/hydrocarbon interface resulting from dipole-image dipole interactions.
236 citations
TL;DR: It is shown how individual drug elimination parameters in patients with renal disease can be estimated from the patient’s creatinine clearance or serum creatInine concentration by means of a simple nomogram which describes the elimination rate of the drug as a fraction of its normal elimination rate constant.
Abstract: Based on the well known linear relationship between the overall drug elimination rate constant and the endogenous creatinine clearance, it is shown how individual drug elimination parameters in patients with renal disease can be estimated from the patient's creatinine clearance or serum creatinine concentration. By means of a simple nomogram the elimination rate fraction is determined which describes the elimination rate of the drug as a fraction of its normal elimination rate constant. Based on the estimated elimination rate fraction the dosage regimen in the patient with renal disease is individually modified according to pharmacokinetic principles. At present the described method can be used with 45 different drugs.
168 citations
TL;DR: Elongation factor Tu is present in a fourfold excess over the amount seemingly involved in protein synthesis and the possibility of a specific role in that location is considered.
Abstract: Elongation factor Tu is present in a fourfold excess over the amount seemingly involved in protein synthesis. It is identical to a major protein which we have found associated with the plasma membrane. The possibility of a specific role in that location is considered.
157 citations
01 Jul 1976
TL;DR: In this paper, it has been shown that there is a rapid exchange of electrolyte solutions and water between aerosol OT micelles in iso-octane occurring during collisions.
Abstract: By means of fluorescent measurements, using Tb 3+ as a probe, it has been shown that there is a rapid exchange of electrolyte solutions and water between aerosol OT micelles in iso-octane occurring during collisions. This process is considered to be analogous to a collision between liquid spheres and a theoretical discussion of this model treats the resultant deformation as a vibration induced during the time of collision. The surfactant molecules move outward from the point of impact during the collision, thus opening a channel through which the solubilizate has time to diffuse from one micelle to the other.
153 citations
TL;DR: A model for the regulation of protein cleavage during T4 development in which about 100 molecules of inactive P21 zymogen are incorporated into the prehead is proposed, which self-inactivates by autodigestion.
132 citations
TL;DR: It is shown that even the most convincing concept thatNSAID exert their action by inhibiting the biosynthesis of prostaglandins leaves several questions unanswered, which may be answered by the results of recent studies which show that acidic NSAID exert a specific pharmacokinetic behaviour leading to high concentrations of these drugs in inflamed tissue and correspondingly causes localized pharmacodynamic effects.
Abstract: 1. 1. Current and older hypotheses on the mode of action of nonsteroid anti-inflammatory drugs (NSAID) are reviewed. 2. 2. It is shown that even the most convincing concept that NSAID exert their action by inhibiting the biosynthesis of prostaglandins (PG's) leaves several questions unanswered. 3. 3. They may be answered by the results of recent studies which show that acidic NSAID exert a specific pharmacokinetic behaviour leading to high concentrations of these drugs in inflamed tissue and correspondingly causes localized pharmacodynamic effects.
131 citations
TL;DR: The simulation of several aspects of capsid maturation (cleavage of P23 to P23∗, stabilization, and lattice expansion) in the polyhead pathway suggest that it parallels the major events of phage T-even capsids maturation, decoupled from any involvement of DNA packaging.
121 citations
TL;DR: Adenylate cyclase stimulation using the highly sensitive assay of Salomon, Londos and Rodbell is reported on, finding its regulatory properties are of particular interest.
117 citations
TL;DR: In this article, the Monte Rosa Granite has been investigated by microscopic, X-ray, wet chemical, electron microprobe, stable isotope and Rb-Sr and K-Ar methods.
Abstract: Nine samples from the Monte Rosa Granite have been investigated by microscopic, X-ray, wet chemical, electron microprobe, stable isotope and Rb-Sr and K-Ar methods. Two mineral assemblages have been distinguished by optical methods and dated as Permian and mid-Tertiary by means of Rb-Sr age determinations. The Permian assemblage comprises quartz, orthoclase, oligoclase, biotite, and muscovite whereas the Alpine assemblage comprises quartz, microcline, albite+epidote or oligoclase, biotite, and phengite.
115 citations
TL;DR: The nature and some of the properties of this genetically related macrophage factor (GRF) were investigated by use of immunoadsorbents and it was shown to contain I region‐coded products (Ia antigens) linked to a small antigenic fragment.
Abstract: Macrophages incubated with soluble antigens for 1–4 days release factors capable of inducing T helper cells. The nature and some of the properties of this genetically related macrophage factor (GRF) were investigated. By use of immunoadsorbents, GRF was shown to contain I region-coded products (Ia antigens) linked to a small antigenic fragment. The genes coding for the Ia antigens detectable in GRF lie in the I region of the H-2 complex.
GRF does not react with anti-immunoglobulin, anti-C3 or anti-human β2- microglobulin antisera, and its activity cannot be removed by antigen immunoadsorbents. GRF is heatlabile, sensitive to proteolytic enzymes and has a molecular weight of about 55 000 Daltons. The relationship of GRF to other factors known to contain I region-coded products and reported to be effective in cell cooperation is discussed.
TL;DR: The sites of action of the restriction enzyme Bgl II on lambda DNA are mapped and this enzyme makes staggered cuts producing sticky ends and produces 5' terminals which are not substrates for polynucleotide kinase.
Abstract: The sites of action of the restriction enzyme Bgl II on lambda DNA are mapped. This enzyme recognises the sequence 5' ...AGATCT...3' and makes staggered cuts producing sticky ends. In lambda DNA, the second A in this sequence is methylated about 50% of the time by a bacterial methylase absent in E. coli dam. In contrast to Bgl II, Bgl I makes many cuts in lambda DNA and produces 5' terminals which are not substrates for polynucleotide kinase.
TL;DR: The structure and absolute configuration of pseurotin, a new metabolite isolated from culture filtrates of Pseudeurotium ovalis STOLK (Ascomycetes), has been shown to be 2-[1′(S), 2′ (S)-dihydroxhex-3′-ene-yl]-3-methyl-8(S)-methoxy-8-benzoyl-9(R)-hydroxy-(5S)-1
Abstract: The structure and absolute configuration of pseurotin (1), a new metabolite, isolated from culture filtrates of Pseudeurotium ovalis STOLK (Ascomycetes), has been shown to be 2-[1′(S), 2′ (S)-dihydroxhex-3′-ene-yl]-3-methyl-8(S)-methoxy-8-benzoyl-9(R)-hydroxy-(5S)-1-oxa-7-aza-spiro[4.4]non-2-ene-4, 6-dione (1), by spectral data and chemical transformations, and by X-ray analysis of its dibromo derivative 2 [1].
TL;DR: The T4 prehead proteinase (T4PPase) as discussed by the authors is an enzyme that cleaves purified prehead proteins to the size found in mature virions in vitro.
TL;DR: The DNA region containing the OR, operator, PR and Prmpromoters and their transcription initiations is sequenced and it is shown that by binding to OR, repressor turns off PR, turns on Prm and at higher concentrations turns off Prm, regulating its own synthesis.
Abstract: The DNA region containing the OR, operator, PR and Prmpromoters and their transcription initiations is sequenced. By binding to OR, repressor turns off PR, turns on Prm and at higher concentrations turns off Prm, regulating its own synthesis. Prm mRNA is unique in beginning immediately with the initiation of translation, without a preceding leader sequence.
TL;DR: In this paper, a quasi-elastic electron from 3He is calculated in the framework of impulse approximation as a test of a ground state wave function calculated from the Reid soft core interaction with the Faddeev technique.
TL;DR: The extended tail sheath of bacteriophage T4 has been used to study the transfer of information from an electron micrograph to the three-dimensional reconstruction obtained from it and two methods have been developed to assess micrograph images of helical particles and their reconstructions.
TL;DR: In this article, the authors considered the case where the energy of the incoming deuteron is below the Coulomb barrier and showed that this reaction which interferes with the direct breakup process, can again be well described in the post-form of the DWBA.
TL;DR: By analysing the properties common to the various structures which may be formed out of this net, it is found that the P23 molecules possess form-determining specificity in terms of an intrinsic curvature of the capsomere bonding.
01 Jan 1976
01 Oct 1976
TL;DR: In this paper, the emission spectrum of tricetylene, A 2 Π g → X 2 ǫ u band system, and of tetraacetylene, X 2 n O o o band, excited in the gaseous phase by controlled electron impact, is reported.
Abstract: The emission spectra of the radical cations of tricetylene, A 2 Π g →X 2 Π u band system, and of tetraacetylene, A 2 Π u →X 2 Π g O o o band, excited in the gaseous phase by controlled electron impact, are reported. The emission spectrum of diacetylene cation, A 2 Π u →X 2 Π g band system, with corrected band intensities is also presented. The lifetimes of the lowest vibrational level of the A 2 Π excited states have been measured as 71±3 ns, 17±2 ns and ⩽6 ns for the cations of diacetylene, triacetylene and tetraacetylene respectively. The lifetimes of the measured excited vibronic levels are shorter. Emission bands from the radical cation of cyanoacetylene and cyanogen were however not detected and these results are discussed.
TL;DR: In this paper, the elastic electron scattering from 4 He at medium momentum transfers is presented and the charge density and rms-radius (1.674 ± 0.012 fm) are obtained from a model independent analysis of all available electron scattering data.
TL;DR: Giant T4 giant phage are found with 14 out of 15 tested temperature-sensitive mutants in gene 24 grown at intermediate temperatures between 33 °C and 37 °C, suggesting that their formation may be caused by a dosage effect of P24.
TL;DR: It is shown that the effect of overlapping of potential site (so-called "multiple-contact"binding), as may occur with larger ligands, will largely be compensated by a higher degree of cooperativity.
15 Apr 1976
TL;DR: The question is quantitatively examined which general information can be obtained from experimental data of ligand binding to macromolecules if represented by a Scatchard plot, assuming rather general conditions including cooperative behavior.
Abstract: The question is quantitatively examined which general information can be obtained from experimental data of ligand binding to macromolecules if represented by a Scatchard plot. In particular, the curvature as well as the intercepts and slopes at both coordinate axes are analyzed assuming rather general conditions including cooperative behavior (with applications to some simplified cases of interest in practice). The results should provide a basis for attempts to elucidate the binding mechanism of a system encountered in experimental work.
TL;DR: The stereologioal model and the base-line data of normal human liver needle biopsy-specimens are presented and the mean individual volume of human hepatocytes is clearly larger than in rodents.
Abstract: The stereologioal model and the base-line data of normal human liver needle biopsy-specimens are presented. Four reference systems were introduced: 1 cm3 of liver tissue, 1 cm3 of hepatoeyte, 1 cm3 of hepatocytic cytoplasm and the volume of an average “mononuclear” hepatocyte. The sampling was done at three levels of magnification (1,000 ×, 5,000 × and 10,000 ×). A lobular differentiation was not considered. The baseline data show strikingly small variations (s.e. less than 10%) within the individual biopsy specimen and within the group of four biopsies. There is no principal difference between human beings presented here, rats, mice and dogs. Only the mean individual volume of human hepatocytes is clearly larger than in rodents. The problems and limitations of stereological work on liver biopsy specimens are discussed.
TL;DR: In this paper, the torsional angle φ of the N-phenyl ring in isolated benzylideneaniline 1 has been found to be definitely smaller than φ= 90°.
Abstract: From PE.-spectroscopical studies the torsional angle φ of the N-phenyl ring in isolated benzylideneaniline 1 has been found to be definitely smaller than φ= 90°. An approximate valueφ= 36°has been estimated which is even smaller than the one observed in the crystal (φ= 55°) and suggested to prevail also in solutions of 1. A reevaluation of the gas phase optical spectrum of isolated 1 supports a torsional angle similar to that found in the other phases.
Calculations of the most stable conformation of 1 as well as of stilbene and azobenzene by the MINDO/3-technique lead to torsional angles φ= 90° for both phenyl rings in all cases. These results are at variance with the experimental results and suggest that MINDO/3-like its less advanced precursor MINDO/2 or like CNDO/2–is unreliable for low energy processes involving rotation of π-systems connected by essential single bonds.
It is concluded that the π-energy of benzylideneaniline, like that of stilbene or azobenzene, would favor a planar conformation. The increased torsional angle in 1 as compared to the other two iso-conjugate systems arises from a larger steric interaction between phenyl- and bridgeprotons.
TL;DR: In this paper, the authors derived inductive substituent constants σIq from the pKa values of 38 4-substituted quinuclidinium perchlorates.
Abstract: Thermodynamic pKa-values have been determined for 38 4-substituted quinuclidinium perchlorates. They are remarkably sensitive to the polar effect of the substituent and cover a range of 3.63 pKa units. Furthermore, they vary linearly and almost equally with temperature since the contribution of the TΔS° term to the free energy of ionization is relatively small and constant. The magnitude of the polar effect of the 4-cyano group varies with the solvent and appears to depend on its ability to form hydrogen bonds to the substituent rather than its dielectric constant.
New inductive substituent constants σIq are derived from the pKa values. Their correlation with known inductive constants is only fair or unsatisfactory, especially as regards the relative order of hydrogen and the alkyl groups. The discrepancies can be ascribed mainly to the different models used to derive the substituent constants.
TL;DR: Responses of fetal acid–base balance to duration of second stage of labour and response of fetal Acid-base Balance to Duration of Second Stage of labour are studied.