Absorption and intestinal catabolism of fatty acids in the rat: effect of chain length and unsaturation

1991

Simultaneous portal blood absorption and intestinal mucosal catabolism of labelled fatty acids were investigated. Anaesthetized adult Wistar rats were infused intraduodenally either with 90 mumol of capric (C10:0), oleic (C18:1), linoleic (C18:2) or arachidonic (C20:4) 1-14C acids or with 30 mumol of each labelled fatty acid in addition to 30 mumol of oleic acid and 30 mumol of monopalmitin. For mixed infusates, experiments were carried out with two additional long-chain fatty acids: palmitic (C16:0) and erucic (C22:1) 1-14C acids. Radioactivity was quantified in the lipids and in the catabolic products in portal blood recovered at 5 min intervals for 1 h after infusion. At the end of the e…

Chitin synthetase activity in Candida albicans: subcellular distribution in yeast cells and protoplasts

1991

Chitin synthetase activity was detected in a partly zymogenic form in cell-free homogenates obtained from C. albicans yeast cells and protoplasts of the same type of cells. By isopycnic centrifugation on sucrose gradients of the cell-free homogenates two fractions with chitin synthetase activity were obtained: one was associated with the plasma membrane (labelled with [ 3 H]concanavalin A (con A) and buoyant density 1·195 g ml −1 ) in a partly active state, and the second was in the cytoplasm, where the enzyme was in a particulate fully zymogenic form, lacking affinity to con A. The buoyant density of the enzyme found in this location depended on the method of cell breakage. Lysis of partly…

Relaxation phenomena in mixed isomeric alcohols by Mandelstam-Brillouin scattering

1991

Mandelstam-Brillouin scattering data in mixed isomeric alcohols n-pentanol (nPe-OH) and 2-methyl-2-butanol (2Me-2BuOH) are presented. The hypersonic velocity and normalized absorption are measured as a function of the scattering angle, in the temperature range from - 15-degrees-C to + 45-degrees-C, and as a function of n-PeOH molar fraction going from the pure n-PeOH to the pure 2Me-2BuOH. The experimental results confirm the existence of a shear relaxation phenomenon in the GHz region, that has been previously detected in pure liquids. The temperature dependence of the relaxation time tau-s and of the shear modulus G-infinity evaluated within viscoelastic liquid models, support the existen…

Measurement of magnetic monopole transition in electron scattering fromO16as direct test of dispersive effects

1991

For the first time an experiment has been performed to measure a magnetic monopole transition in inelastic electron scattering. In {sup 16}O the 0{sup +}{r arrow}0{sup {minus}} transition to the level at {ital E}{sub {ital x}}=10.957 MeV has been observed with a cross section of {ital d}{sigma}/{ital d}{Omega}=(5.4{plus minus}3.8){times}10{sup {minus}37} cm{sup {minus}2}/sr. Measurement of this transition is a direct signature of two-step contributions in electron scattering. Our measurement is in good agreement with the strength calculated for this transition.

correction to ƒB

1991

Abstract The 1/m corrections to the B-meson decay constant ƒB (and the D-meson decay constant ƒD) of the heavy quark effective theory are calculated in the Green function approach. The corrections are found to be sensitive to the difference of the meson mass mB and the heavy quark mass mb. For mb=4.81 GeV we obtain a 100% correction to the heavy quark limit mb=mB. The scaling law of the ratio ƒB/ƒD is, however, quite well satisfied because of cancellations. For reasonable values of quark masses we obtain ƒ B = (130±20) MeV and ƒ D = (170±10) MeV .

A feature of caudate control of focal hippocampal epilepsy: evidence for an anterograde pathway

1991

Previous experimental evidences showed that the caudate nucleus has a modulatory effect on hippocampal epilepsy. The caudate's regulating action might reach the hippocampus either via the septal region or, retrogradely, via the accumbens nucleus. In order to obtain new data about the pathway involved in caudate hippocampal influence the spreading of abnormal activity towards the nucleus accumbens was studied. Furthermore the effects of caudate stimulation in animals with electrolytic lesions of the nucleus accumbens were analyzed. It was observed that abnormal penicillin-induced activity spreaded from the hippocampus to the nucleus accumbens in about 30 minutes. In animals with and without …

Systems tracts and depositional sequences in a carbonate setting: a study of continuous outcrops from platform to basin at the scale of seismic lines

1991

Abstract The application of sequence stratigraphy concepts to carbonates is feasible and this paper presents an example of its successful application. The continuity and lateral extent of outcropping sedimentary sections observed at the scale of a seismic line from platform to basin in the Southern Vercors Plateau (western Alps, France) confirm the validity of sequence stratigraphy concepts when applied to carbonate depositional systems. From the stratal patterns displayed in outcrop, we determined that carbonate lowstand systems tracts are major components in the basin, even in the deep pelagic realm. Transgressive and highstand systems tracts are very thin, a response to starvation. In co…

Properties of tuberomammillary histamine neurones and their response to galanin.

1991

Histaminergic neurones in the tuberomammillary nucleus possess electrophysiological properties which distinguish them from other neurones in their neighborhood. Their resting potential is -50 mV and they are spontaneously active at about 2 Hz in a slice preparation. They display a transient outward rectification and an anomalous inward rectification. Bath application of galanin (0.1 microM) reduced their firing rate significantly and hyperpolarized them slightly.

Protective effect of N-acetylcysteine on ischaemia-induced myocardial damage in canine heart.

1991

The glutathione redox pathway is an important antioxidant system in the myocardium. N-Acetylcysteine is a low molecular weight glutathione precursor that has been used clinically to replenish glutathione stores. The present study was aimed at evaluating the protective effect of N-acetylcysteine on myocardial damage resulting from permanent coronary occlusion (without reperfusion) in anaesthetized dogs. N-Acetylcysteine (150 mg kg−1 i.v.) administered 2 min before occlusion rerduced infarct size in dogs subjected to 24 h ischemia. The infarct size as a percentage of the area at risk was 86.8 ± 3.6% (n = 11) in control (salinetreated) dogs and 68.2 ± 2.4% (n = 7; P < 0.05 vs control) in N-ace…

The PAPIA system

1991

In 1983 an Italian research program was begun for the design, simulation and construction of a multiprocessor image processing system. After a first phase devoted to the comparison of suggested and existing systems and to the definition of a set of benchmarks, a new system was defined. The structure of this new system is introduced here: it is based on a fine-grained pyramid of processors built up by means of a pyramidal cell implemented on a VLSI multiprocessor chip. The peculiarities and the capabilities of the processing element are highlighted. The complete hardware and software system has been fully designed and is described. A first working prototype has been built and is now operatio…

Li2OSiO2Al2O3MeIIO Glass-Ceramic Systems for Tile Glaze Applications

1991

In order to verify the possibility of using glass-ceramic materials as tile coatings, the devitrification processes of three industrial formulations belonging to the Li2O─Al2O3─SiO2 glass-ceramic system were investigated by differential thermal analysis, X-ray diffractometry, scanning electron microscopy, and IR spectroscopy. Compositional variations were made by addition of large amounts of MgO or CaO or PbO (ZnO) oxides as well as through smaller additions of other oxides. In these systems the surface crystallization contributes appreciably to the bulk crystallization mechanism. All the systems investigated show a high tendency toward crystallization even at very high heating rates, devel…

Calcium-binding sites in the inner ear after pure-tone stimulation

1991

Five guinea pigs were exposed to an interrupted 90 dB SPL pure tone of 3.2 kHz for a total application time of 5 min. Following sound application all animals were decapitated and the cochleae were removed. After that, calcium-binding sites were located by the potassium pyroantimonate precipitation method. Another three animals served as control animals and did not receive the sound treatment. Findings confirmed previous studies showing the spatial arrangements of precipitate rich regions in the inner ear's two acellular structures (the basilar membrane and tectorial membrane) and the two cellular structures (the inner hair cells and Huschke's teeth). By using semiquantitative evaluation we …

Biochemical properties of MHC class II molecules endogenously synthesized and expressed by mouse Langerhans cells

1991

The cell surface expression and biosynthesis of Langerhans cells (LC)-derived major histocompatibility complex (MHC) class II molecules from epidermal cells (EC) prepared freshly and cultured for up to 3 days was investigated. Based on the constitutive expression of MHC class II determinants by LC, a panning and magnetic bead selection procedure was employed, yielding 65% and 86% of I-A+ cells, respectively. Phenotypical and cytochemical examinations revealed that the two LC preparations were free of contaminating macrophages as well as B and T cells. Freshly prepared enriched LC were highly efficient in the stimulation of protein antigen-specific T cell clones, while LC purified from short…

Aeromonas salmonicida in Finland: pathological problems associated with atypical and typical strains

1991

. Aeromonas salmonicida was studied at fish farms producing salmonid smolts in northern and central Finland from 1982 onwards. Aeromonas salmonicida subsp. salmonicida has been causing epizootics in salmon, Salmo salar L., and trout, S. trutta L., at two coastal farms in northern Finland sinee 1986, involving 1–29% mortality in the fish-rearing units affceted. The disease causes more serious losses of sea trout yearlings and brood fish than of salmon. The achromogenic atypical A. salmonicida proved to be the most common bacterial disease in brown and sea trout at one farm in northern Finland throughout the period, causing constant heavy losses, mainly of fingerlings, especially in 1982–1986…

The endometrium in human assisted reproduction.

1991

SU(2|1) symmetry, algebraic superconnections and a generalized theory of electroweak interactions

1991

We discuss an extension of the standard model of electroweak interactions which incorporates the usual gauge fields and the Higgs fields in one generalized Yang-Mills field (or superconnection). It is shown that both this Yang-Mills field and the corresponding field strength (supercurvature) take their values in the real, graded Lie algebra SU(2|1). The lagrangian as obtained from this superconnection yields the standard model with interesting predictions for masses and couplings. The primordial, larger symmetry is realized as a hidden symmetry. The odd part survives in relations between couplings and masses, while the even part is broken to U(1)em, as usual, though in “reverse order” as co…

Isolation and identification of the antibacterial compounds from Helichrysum stoechas.

1991

Fractionation of the dicholoromethane extract of the aerial parts of Helichrysum stoechas yielded seven isolates (1-7), which exhibited varying antimicrobial activity against Gram-positive bacteria. Pure compounds 1-3 have been previously reported in the same species and 4 and 5 were identified as italipyrone and plicatipyrone, previously isolated from H. italicum and H. plicatum. The two other isolates are helipyrone (6) and homoarenol (7) mixed with related substances. Compound 6c (4,4'-dihydroxy-5,6,5',6'-tetramethyl-3,3'-methylen-di-pyr-2-one) and 6b helipyrone with one methyl substitution, have not been previously reported in other species.

Neuropsychological deviations in healthy relatives of schizophrenics

1991

Alkaline hydrolysis/methylation-acetylation: a new technique for ultrastructural DNA cytochemistry.

1991

SUMMARY A new technique for the visualization of DNA-containing structures in electron microscopy is described. Samples of glutaraldehyde-fixed bone marrow from rats were subjected to alkaline hydrolysis to remove RNA and the phosphate of phospho-proteins, followed by a combined blockage of protein carboxyl and amino groups through methylation-acetylation. After uranyl acetate staining of epoxy-embedded ultrathin sections, chromatin from all cell types showed a highly selective and intense electron opacity. Staining methods for DNA were also positive in semithin sections. This simple procedure could be very useful in ultrastructural cytochemistry of DNA and chromatin.

The crystal structure of neodymium and europium chromate heptahydrate: Synthesis, infrared spectra, and thermal behavior of lanthanoid chromate hepta…

1991

Abstract The crystal structures of Nd2(CrO4)3 · 7H2O and Eu2(CrO4)3 · 7H2O were determined by the conventional single-crystal X-ray diffraction technique. In addition, unit cell dimensions were measured for La2 (CrO4)3 · 7H2O and Sm2(CrO4)3 · 7H2O. All these compounds are isostructural. Crystals are monoclinic, space group P2 1 c . For Nd2(CrO4)3 · 7H2O, a = 8.052(4) A, b = 19.143(4) A, c = 13.326(6) A, β = 128.15(4)°, Z = 4, Dx = 3.14 Mg · m−3, T = 296(1); and for Eu2(CrO4)3 · 7H2O, a = 7.965(3) A, b = 18.985(4) A, c = 13.185(4) A, β = 128.00(2)°, Z = 4, Dx = 3.29 Mg · m−3, T = 296(1). Ln atoms are nine-coordinated so that the coordination polyhedron is a tricapped trigonal prism for Ln1 a…

T lymphocyte-stimulating microbial toxins as ?superantigens?

1991

Infectious pathogens generally have to cope with the host's adaptive immune system, i.e., T and B lymphocytes. Common evasion mechanisms in this complex interaction are antigenic variations, the escape to immunologically priviledged sites or the use of immunosuppressive mechanisms. Many bacteria and other microorganisms eleborate soluble factors or toxins that act suppressively on cells of the immune system, such as pore-forming molecules or proteins that interfere with the function of G proteins. Gram-positive cocci and a mycoplasma have developed an extremely potent mechanism of T cell stimulation by closely mimicking recognition of specific antigen. From the functional similarity to anti…

Bioeffects of ultrasound: an experimental study on human embryos.

1991

Abstract The foetuses of 10 women at 9–12 weeks gestation were irradiated with ultrasound under typical diagnostic exposure conditions immediately prior to abortion. Electron microscopy of liver fragments revealed neither morphological nor structural changes.

Antigenic cell wall mannoproteins in Candida albicans isolates and in other Candida species.

1991

Polyclonal antibodies (pAbs) and monoclonal antibodies (mAbs), raised against mannoprotein components from Candida albicans ATCC 26555 (serotype A) blastoconidia and mycelial cell walls, were used to investigate antigenic similarities among wall mannoproteins from other C. albicans serotype A and B strains, and from C. tropicalis and C. guilliermondii. Radioactively labelled walls isolated from cells grown at either 28 degrees C or 37 degrees C were digested with a beta-glucanase complex (Zymolyase 20T) to release cell-wall-bound mannoproteins. Numerous molecular species with different electrophoretic mobilities were released from the various isolates. Differences appeared to be related to …

DNA image cytometry. A prognostic tool in squamous cell carcinoma of the esophagus?

1991

In 45 patients who underwent an esophagus resection due to a squamous cell carcinoma, in addition to the TNM classification and usual morphologic criteria, the paraffin-embedded material underwent deparaffinization, was rehydrated, and was mechanically and enzymatically processed into a single-cell solution. For evaluating the DNA histogram this was analyzed with the help of automatic single-cell cytophotometric study. The method, contrary to that of flow cytometric study, allows for the selective analysis of tumor cells due to the electronically, previously given selection criteria, whereas artifacts, stroma, and infection cells remain excluded from analysis. The multivariate analysis show…

Geochemical investigations of submarine volcanic exhalations to the east of Panarea, Aeolian Islands, Italy

1991

Abstract Results are presented on scubadiving investigations carried out on thermal manifestations in the area of Panarea (Aeolian Islands). The area investigated falls inside a caldera which extends from the main island to the group of islets located to the northeast. The distribution of the gaseous manifestations is regulated by the NE-SW, NW-SE and N-S regional tectonic directrices, through which the more recent basic magma intruded, giving rise to dikes and pillow lavas. f O 2 -temperature relation of the gases sampled in the investigated area was calculated to be: log f O 2 = 11−24,593/ T which indicates that a buffering mechanism acted on the gases as they cooled down during their asc…

Independence and interdependence of group judgments: Xenophobia and minority influence

1991

A first experiment examined the effects of two methods of dividing resources between Swiss nationals and foreign residents in a study involving 118 subjects. Subjects gave judgments involving either interdependent allocation (resources allocated to the outgroup cannot be allocated to the ingroup) or independent allocation. The results indicated that the socio-cognitive functioning preferred by subjects varies as a function of their view of outsiders. Interdependence of judgments was more characteristic of the most xenophobic subjects, whereas the least xenophobic were more likely to reason in terms of independence. On the other hand, intermediate subjects (those who were clearly neither for…

false

1991

The sanidic polyamide [NM-Ph(CO 2 R) 3 (CO 2 Me)-NMCO-Ph(OR) 2 CO] n (R=C 12 H 25 ) is studied. It is shown that this polymer has a biaxial structure with quasi 2-D long range translational correlations. The correlations in one direction are limited by the length of the molecule. The oriented regions are separated by regions in which the molecules are less oriented

Surgical aspects of urolithiasis in children.

1991

Operative management of renal calculi has changed radically in the last decade. New operative techniques. the use of intra-operative ultrasound and Doppler sonography have even made possible the removal of complete staghorn calculi in short and kidney-preserving procedures. The introduction of percutaneous nephrolithotomy and stone extraction using a specially designed ureteroscope and, above all, the clinical application of extracorporeal shock wave lithotripsy have made stone surgery less invasive and have provided a higher rate of preservation of kidney function.

Scientific Proceedings Second International Symposium on Cytostatic Drug Resistance

1991

Nicotinic cholinoceptive neurons of the frontal cortex are reduced in Alzheimer's disease.

1991

The cellular distribution of nicotinic acetylcholine receptors was studied in the frontal cortex (area 10) of 1) Alzheimer patients and compared to 2) age-matched and 3) middle-aged controls using the monoclonal antibody WF 6 and an immunoperoxidase protocol. Statistical analysis revealed significant differences between the number of labeled neurons among all three groups tested (middle-aged controls greater than aged controls greater than Alzheimer cases). No differences were seen for cresyl violet-stained samples. These findings underline that the nicotinic receptor decrease found with radioligand binding may reflect a postsynaptic in addition to a presynaptic component.

Electron-nucleus interactions (Part 1)

1991

false

1991

The Triassic of the NW Iberian Ranges consists of two carbonatic formations equivalent to the Upper Carbonatic Formation of the Muschelkalk Facies and pass laterally into siliciciastic deposits to the NW. Fossillocalities have been found in both formations. Taphonomic and sedimentologic studies allow for the interpretation as autochthonous associations of the infaunal Bivalves of shallow water marine environments with siliciciastic input. Three faunal associations have been distinguished: 1. Costatoria-Lyriomyophoria association, found in the lower carbonatic formation and the equivalent siliciciastic formation; 2. «Teruel Fauna» association, found in the upper carbonatic formation; 3. Ling…

Cu cluster shell structure at elevated temperatures

1991

Equilibrium structures of small (3--29)-atom Cu clusters are determined by simulated annealing, and finite-temperature ensembles are simulated by Monte Carlo techniques using the effective-medium theory for the energy calculation. Clusters with 8, 18, and 20 atoms are found to be particularly stable. The equilibrium geometrical structures are determined and found to be determined by a Jahn-Teller distortion, which is found to affect the geometry also at high temperatures. The ``magic'' clusters retain their large stability even at elevated temperatures.

Latvijas Universitātes Tautsaimniecības un tiesību zinātņu fakultātes tiesību zinātņu profesora Aleksandra Būmaņa kapakmenis Rīgas Meža kapos pēc atk…

1991

The tombstone of Alfrēds Būmanis, member of the Latvian Student fraternity Fraternitas Lettica, Latvian lawyer and professor of law at the Faculty of Economics and Law of the University of Latvia, at the Riga Forest Cemetery after the unveiling.

Latviešu studentu korporācijas Fraternitas Lettica saime ierodas Rīgas Meža kapos uz profesora Aleksandra Būmaņa kapakmeņa atklāšanu

1991

The Latvian Student fraternity Fraternitas Lettica, accompanied by its guard of honour, arrives at the Riga Forest Cemetery to participate in the unveiling of the tombstone of its member, Alfrēds Būmanis, Latvian lawyer and professor of law at the Faculty of Economics and Law of the University of Latvia. The unveiling of the tombstone coincides with the collapse of the USSR and the restoration of Latvia's independence.

Chemistry of pheromonal and defensive secretions in the nymphs and the adults ofDysdercus cingulatus Fabr. (Heteroptera, Pyrrhocoridae)

1991

59 ref.; International audience; The exocrine secretions from the nymphs and the adults of both sexes in D. cingulatus were chemically investigated. Seven compounds were identified in the anterior glands, and eleven in the median dorsoabdominal glands of nymphs and adults of both sexes. Fifty-five compounds were identified in the defensive glands (34 in posterior dorsoabdominal glands ofnymphs and 21 in metathoracic glands of adults), and six in the sternal glandular epithelium of the males. The biological function of the glandular secretions and of their identified compounds were investigated and are discussed.