Showing papers by "University of Bergen published in 1986"

Haematogenous metastastic patterns in colonic carcinoma: An analysis of 1541 necropsies

Abstract: The sequence of events in haematogenous metastasis from colonic carcinoma was analysed, using 1541 necropsy reports from 16 centres. The findings are consistent with the cascade hypothesis that metastases develop in discrete steps, first in the liver, next in the lungs and finally, in other sites. Deviations of necropsy findings from the cascade model are largely explained on the basis of false negative reports. In only 216 of 1194 cases was there suggestive evidence that metastatic patterns (excluding lymph nodes) were causally related to lymphatic or non-haematogenous pathways. The incidence of metastatic involvement in 'other' (quaternary) sites correlated with target organ blood-flow (ml min-) per g, only when bone marrow and thyroid were excluded. In the thyroid the incidence was lower than expected on the basis of blood flow per g tissue; this may indicate that the thyroid is an unfavourable site for metastatic growth of colonic carcinoma. In the bone marrow it is higher; the latter may be due to delivery of cancer cells via both arterial blood and the vertebral venous plexus. Recognition of this pattern of metastases in the bone marrow could be important with respect of diagnosis and therapy, in patients with colonic carcinoma.

Dissociation between antinociceptive and anti-inflammatory effects of acetylsalicylic acid and indomethacin in the formalin test.

Abstract: It is assumed that the mild analgesia produced by acetylsalicylic acid (ASA) and indomethacin is due to a common mode of action, namely inhibition of the cyclo-oxygenase reaction in the synthesis of prostaglandins. It has, however, been difficult to separate the influence of the anti-inflammatory activity from pure analgesia in standard animal tests using a fully developed inflammatory state. In the present experiments a modification of the formalin test in mice is used. Licking of the injected paw is recorded after the injection of a small nociceptive amount of formalin (20 μl, 1%). The results show that the response to formalin is biphasic with an early (0–5 min) and a late (20–30 min) phase of high licking activity. ASA had a dose-dependent antinociceptive effect during both the early and the late phases. In contrast, antinociceptive effect of indomethacin was found only during the late phase. On the basis of these results it may be suggested that inhibition of the cyclo-oxygenase reaction has no major effect on the early phase in the formalin test. This also suggests that ASA and indomethacin are antinociceptive through partially different modes of action. In addition to an anti-inflammatory effect common to both drugs, ASA may have a direct antinociceptive action.

Primary and diagenetic carbonates in the anoxic sediments of Lake Bosumtwi, Ghana

Abstract: Cores of organic-rich muds from the tropical meteorite crater Lake Bosumtwi, Ghana, contain laminae of authigenic calcite polyhedra and aragonite needles, as well as scattered diagenetic calcite, Mg-calcite spherulites, and aggregates of dolomite crystals. Their respective origins are traced by analyses of oxygen and carbon stable isotopes. Anoxic dolomite and Mg-calcite formed in pore waters reflecting highest degrees of evaporative concentration and high rates of methanogenesis. Carbon dioxide reduction must have been the dominant methanogenic pathway, producing diagenetic carbonates with ..delta../sup 13/C values up to + 27% PDB. This example shows the inherent problems of interpreting bulk samples with progressive mineralogical sequences of calcite to Mg-calcite to aragonite to dolomite merely in terms of Mg/sup 2 +//Ca/sup 2 +/ in lake waters. It provides a model for the interpretation of ancient lacustrine carbonates from organic-rich environments.

Dependence of the rate of release of phosphorus by zooplankton on the P: C ratio in the food supply, as calculated by a recycling model1

Abstract: In two enclosure experiments, Daphnia pulex ingested cryptophytes, bacteria, and probably detritus particles. The specific clearance rate of the zooplankton increased when the concentration of food decreased. The P : C ratio of the food also increased. More than 92% of the particulate phosphorus was located in the living cells (algae and bacteria); the detritus was practically phosphorus-free. The specific release rate of phosphorus estimated for the daphnids by use of the recycling model increased as the P : C ratio of the food increased and became zero at a critical low P : C ratio, Q. of 6-8 pg P mg-’ C. At this concentration, all the ingested phosphorus is needed for growth and reproduction, and no release of the element can be expected. This indicates that Daphnia may experience P limitation in nature, since the P : C ratio of P-starved algae and detritus may be considerably ~6-8 pg P mg-l C. The use of mass balance also appears to be suitable for modeling phosphorus and carbon fluxes through zooplankton in pelagic ecosystems.

Oligodendroglioma. Histologic evaluation and prognosis.

Abstract: All oligodendrogliomas registered in Norway during a 25-year period (1953-1977) were studied to establish the frequency of different histologic features and to compare them with survival data of the patients. The minimum observation time was five years. The original tumor specimens from 208 patients were independently reexamined by two pathologists. The characteristic oligodendroglioma of this series was of medium cell density (53% of lesions), with moderate nuclear atypia, with vascular endothelial proliferation (53%), calcification (56%), with from one to five mitotic figures per ten high power fields, and without microcystic degenerative changes (58%). Subpial tumor cell infiltration, perivascular lymphocytic infiltration and local leptomeningeal invasion were present in a minority of cases. In 11 cases autopsy material was the only source of diagnosis. Microcysts, necrosis, and cell density were the only histologic features of prognostic significance. Subpial infiltrative growth was of suggestive prognostic value. There was no significant association between the number of mitotic figures and survival. Vascular endothelial proliferation, calcification, pronounced nuclear atypia, perivascular lymphocytic infiltration and local leptomeningeal invasion were of no significant prognostic value. Age at operation did not alter these conclusions, neither did sex nor duration of preoperative symptoms.

Anhydrous P-T phase relations of near-primary high-alumina basalt from the South Sandwich Islands

Abstract: Anhydrous P-T phase relations, including phase compositions and modes, are reported from 10–31 kbar for a near-primary high-alumina basalt from the South Sandwich Islands in the Scotia Arc The water content of natural subduction-related basalt is probably 27 kbar) garnet is the liquidus phase followed by clinopyroxene, then quartz/coesite at lower temperatures At intermediate pressures (17–27 kbar), clinopyroxene is the liquidus phase followed by either garnet, quartz, plagioclase, then orthopyroxene or plagioclase, quartz, garnet, then orthopyroxene depending on the pressure within this interval At all lower pressures, plagioclase is the liquidus phase followed at much lower temperatures (∼100° C at 5 kbar) by clinopyroxene The absence of olivine from the liquidus suggests that the composition studied here could not have been derived from a more mafic parent by olivine fractionation at any pressure investigated, and supports the interpretation that it is primary If so, these results also preclude an origin for this melt by partial melting of olivine-rich mantle periddotite and suggest instead that it was generated by partial melting of the descending slab (quartz eclogite) leaving clinopyroxene, garnet, or both in the residue The generally flat REE patterns for low-K series subduction related basalts argue against any significant role for garnet, however, and it is thus concluded that the composition studied here was extracted at 20–27 kbar after sufficiently high degrees of partial melting (∼50%) to totally consume garnet in the eclogite source Melting experiments on three MORB composition, although not conclusive, are in agreement with this mechanism Results at 30 kbar support an origin for tonalite/trondhjemite series rocks by lower degrees of melting (15–30%), leaving both garnet and clinopyroxene in the residue

Assessment of Global Negative Self-Evaluations and Perceived Stability of Self in Norwegian Preadolescents and Adolescents

Abstract: A special problem in the study of self-esteem is the use of quite different instruments for subjects at different age levels. In the present paper the primary goal was to construct a scale that could be used to assess global self-evaluations in children as well as in adolescents and adults. The scale presented (GSE) based mainly on Rosenberg's Self-Esteem Scale (RSE) was used in this study with 2478 children aged 10 to 15 years. A second goal was to examine the appropriateness of Rosenberg's Stability of Self Scale when used with preadolescents aged 12 to 15. The internal consistency of the new scale (GSE) and of the slightly modified Stability of Self Scale was quite satisfactory (around .80). In addition a principal component analysis showed that the pattern of factor loadings was similar for subjects of different ages, indicating that the items were interpreted and responded to in roughly the same way by fourth through seventh graders. As expected, the GSE Scale correlated quite substantially with self...

Reaggregation of fetal rat brain cells in a stationary culture system. I: Methodology and cell identification.

Abstract: A stationary tissue culture system for reaggregation cultures of rat brain cells is described. Aggregates were formed by placing cells at high concentrations in liquid overlay cultures on a nonadherent nutrient agar surface. No physical stress in the form of rotation or shaking was applied to the aggregating cell population. Transmission electron microscopy and immunohistochemistry showed that the cells developed from homogeneously dispersed, immature cells in Day 4 aggregates, to mature astrocytes, oligodendrocytes, and neurons in Day 20 aggregates. Twenty days and older aggregates had a tightly packed neuropil which was most prominent in a cell-sparse outer layer of the aggregates. When the aggregates were allowed to adhere to a substrate, both glial fibrillary acidic protein (GFAP) positive and negative cells were observed migrating out from the aggregates. Cells giving a positive reaction for neuron specific enolase (NSE) were also present. This reaggregation procedure, with transfer of selected brain cell aggregates into agar-coated multiwells is an alternative three-dimensional culture system which can be potentially useful in the study of morphogenesis and cell interactions in the nervous system.

An annotated check-list of marine molluscs of the Norwegian coast and adjacent waters

Abstract: This check-list is a compilation of the marine molluscs recorded from Norway and the abyssal depths of the Norwegian Sea. Molluscs not recorded from the Norwegian fauna but found on the North Sea plateau, the British North Sea coast, the Swedish west coast, and in Danish waters are also included. Distributional data are provided for each species. Most commonly used synonyms are listed, together with type species for each accepted generic name. Systematical code numbers are included for easy retrieval of information. An alphabetical index of all generic names mentioned concludes the check-list. Recent taxonomic alterations and all distributional records are documented by literature references.

The benthic amphipod fauna of the west-norwegian continental shelf compared with the fauna of five adjacent fjords

Abstract: Twentytwo epibenthic sled samples from the shelf and eleven from five fjords were investigated. The faunal patterns were analysed by means of hierarchical clustering, ordination, and ‘Pseudo F-test’. Three major habitats were distinguished, each characterized by a set of amphipod species: Deep localities on the shelf (247–520 m), shallow localities on the shelf (147–272 m), and fjord localities. Multiple stepwise regression analysis indicated that the distribution pattern of the amphipods is correlated with the ‘bathymetric isolation’ of the localities and sediment factors. Shannon-Wiener diversity index (H') and rarefaction analysis were used to investigate diversity patterns. Shelf sites showed higher diversity than fjord sites. Diversity (H') is significantly correlated with bathymetric isolation, distance from shelf-slope break, depth, and mean grain size in phi-scale. Three hypotheses are suggested as explanations to the lower diversity in the fjords than on the shelf.

Effects of the putative 5-HT1A receptor agonist 8-OH-2-(di-n-propylamino) tetralin on nociceptive sensitivity in mice

Abstract: The ability of 8-OH-2-(di-n-propylamino)tetralin (8-OH-DPAT) to alter nociceptive sensitivity in mice was studied using the tail-flick, hot-plate and formalin tests. Subcutaneous (SC) adminstration of 8-OH-DPAT (0.63–1.0 mg/kg) dose-dependently increased the temperature at which hindpaw lick occurre in a hot-plate test using slowly rising temperature and increased the latencies to hindpaw lick, but reduced the latencies to jump in a conventional hot-plate test. Intracerebroventricular (ICV) injections (0.25–1.0 μg) produced similar results in the conventional hot plate test. Following intrathecal (ITH) injections (0.25–1.0 μg), however, the latencies to hindpaw lick were elevated without any change in jump latencies. In the formalin test a low systemic dose of 8-OH-DPAT (0.63 mg/kg) elicited hyperalgesia, while hypoalgesia was found after a high dose (1.0 mg/kg). ICV injection of 1.0 μg produced hypoalgesia in the formalin test while the same dose injected ITH was without effect. 8-OH-DPAT did not alter tail-flick latencies, either by SC, ICV or ITH administration. Previous studies have shown that 8-OH-DPAT stimulates central serotonergic receptors, and shows selectivity for the 5-HT 1A recognition site. The present findings indicate an involvement of 5-HT 1A receptors in the processing of nociceptive information both at spinal anpraspinal sites. However, stimulation of 5-HT 1A receptors does not seem to affect spinal, nociceptive reflexes.

Radiographic diagnoses and treatment decisions on approximal caries.

Abstract: The purpose of the study was to examine the quality of radiographic caries diagnosis by dentists; the frequency of operative treatment decisions; and the frequency and pattern of proposals to fill sound surfaces. Radiographs of 68 approximal surfaces of extracted teeth were duplicated and examined by 243 dentists. A "true" diagnosis was established by direct inspection and probing. Great variation existed in diagnostic quality between dentists. Restoration therapy made up 15.6 of surfaces on average (SD = 6.5, range 0-66). Fillings were proposed for about 5% of the sound surfaces. About 25% of the dentists accounted for more than 80% of the treatment proposed for sound surfaces.

Nucleotide exchange between cytosolic ATP and F-actin-bound ADP may be a major energy-utilizing process in unstimulated platelets.

Abstract: About 40% of the cytosolic ADP of human platelets is tightly bound to protein and the complex is precipitated from the cells by 43% ethanol. We show here that this ADP is bound to F-actin by three criteria (a) copurification with F-actin, (b) specific extraction with water and (c) by specific interaction with DNase I. Platelets contain 0.3 mumol/10(11) cells of this F-actin--ADP complex compared to the total actin content of 0.8 mumol/10(11) cells, which is consistent with the view that actin is maintained in different pools (F-actin--ADP, profilactin, G-actin). In intact platelets the F-actin-bound ADP turns over rapidly and we have determined a turnover rate at 37 degrees C of 0.1 +/- 0.025 s-1 by using a double-labelling procedure. This rapid turnover indicates that F-actin in intact platelets is in a very dynamic state, which may be necessary for rapid responses to stimuli. If it is assumed that the source of the ADP bound to F-actin is cytosolic ATP, the turnover of F-actin ADP measured represents an ATP-consuming process that would account for up to 50% of total ATP consumption in resting platelets.

Treatment of Cushing's Disease in Childhood and Adolescence by Stereotactic Pituitary Irradiation

Abstract: . Eight children with Cushing's disease aged 6-18 years were treated with external radiation to the pituitary gland using 60Co gamma radiation given with stereotactic technique. The dose given varied between 50 and 70 Gy. The observation time was 2.6 to 6.75 years. Seven children had a clinical remission with normal urinary Cortisol excretion. One child had insufficent effect of two irradiations and underwent bilateral adrenalectomy. In the patients in remission the growth velocity increased during the first year after treatment but growth retardation occurred again during the second year. Insufficient growth hormone secretion was demonstrated in all subjects. Two patients were given thyroxine substitution and three showed evidence for secondary hypogonadism. In conclusion, stereotactic pituitary irradiation was effective in normalizing the excessive glucocorticoid production in children with Cushing's disease. However, with the doses used, it was not possible to maintain a normal anterior pituitary function.

Separate memory laws for recall of performed acts

Abstract: The present study was inspired by an experimental report by Cohen (1981). where recall of subject performed minitasks was demonstrated to give serial position curves without primacy effect. The question raised was whether this deviation implied the formulation of new memory laws. Eight new experiments were conducted. Two of them replicated Cohen's observations; one with concretely performed acts, and one with symbolically performed acts. A third experiment examined recall of proposed, nonperformed acts, with results similar to those found in the other minitask experiments. Four experiments studied the effect of visually imagining act performance, again with results which demonstrated the existence of interesting similarities between the different types of act recall. Several of the experiments explored the role of self-involvement and task familiarity, and the last experiment was specially designed to test a task-difficulty hypothesis. The results were discussed in terms of a representation-system theory, a nonstrategic lack-of-rehearsal interpretation, and in terms of a general problem-solving account. None of these theories were found, all observations taken together, to have been clearly supported or clearly disproved, and more evidence was therefore deemed necessary before new memory laws need to be postulated.

Clinical and radiographic assessment of approximal carious lesions.

Abstract: The aim of the study was to compare the radiographic diagnosis of approximal carious lesions with visual observations of the approximal surfaces and within drilled Class II cavities (made into the pulp). Sound (n = 28) and carious (n = 123) approximal surfaces of extracted premolars and molars were radiographed. The radiographs were studied by seven observers to diagnose caries. Lesions without cavitation were most often classified as sound (61.3%). When lesions had cavities, the rate of detection increased to 89.1%. Sound surfaces were erroneously classified as carious in 15.7% of cases. Statistically, about 6 out of every 10 qualitative assessments of lesion depth on the basis of radiographs correctly recorded lesions as being in enamel or extending into dentin. The interexaminer variation in radiographic caries diagnoses were mostly due to difference in diagnostic criteria, whereas differences in diagnostic capability were less important.

Methods for Production of Intense Beams of Unstable Nuclei: New Developments at ISOLDE

Abstract: An overview of progress in the target and ion source techniques at the ISOLDE on-line mass separator is given. The production of high intensity beams of mass-separated radioactive nuclei by bombardment of targets with 600 MeV protons and 910 MeV 3He from the CERN synchro-cyclotron is discussed. Off-line tests performed in order to clarify the release properties of different target materials are described. The targets are metal powders or foils, alloys, carbides, oxides, intermetallic compounds or molten metals. The influence of reactive gases on the release rates and progress in ion-source techniques are also discussed. Recent on-line tests are described in details, and systems are suggested for the production of elements which are not yet available as primary products in on-line mass separators.

In situ characterization of mononuclear cells in human chronic marginal periodontitis using monoclonal antibodies

Abstract: Acetone fixed cryostat sections from 25 patients with adult chronic marginal periodontitis were characterized using an indirect immunofluorescence technique with monoclonal antibodies. The amount of B lymphocytes (Leu-12 positive) varied considerably between the specimens and were usually seen in largest numbers in the most apical parts of the cellular infiltrates beneath the pocket epithelium (PE). Varying amounts of T lymphocytes (OKT 3 positive) were demonstrated in all specimens. The amount of T helper cells (OKT 4a positive) exceeded that of T suppressor/cytotoxic cells (OKT 8 positive) in the cellular infiltrates beneath the PE (OKT 4a/ OKT 8 =1.13). There was a more even distribution of these cell types beneath the oral gingival epithelium (OGE). Langerhans cells were observed within and occasionally subjacent to the OGE. Scattered macrophages (Leu-M3 or OK Ia 1 positive) were observed in the inflammatory cell infiltrates and on the connective tissue papillae beneath the OGE. HLA-DR antigen reacting with OK Ia 1 was present on cells corresponding to OKT 6 positive cells in the OGE and subjacent to the OGE as well as in the inflammatory cell infiltrates beneath the PE and in the perivascular infiltrates. In some specimens HLA-DR antigen was also found to be associated with keratinocytes in the outer parts of the OGE. Occasional NK cells (Leu-7 positive) were localized inside and subjacent to the OGE. There was a considerable variation with respect to the number and distribution of the various mononuclear cells between specimens and from section to section from the same specimen.

Genetic variation of ascaridoid worms with different life cycles.

Abstract: The hypothesis that genetic variation of populations is positively related to the degree of environmental variation they experience was tested by several authors (e.g., Bryant, 1974a, 1974b; Hedrick et al., 1976; Valentine, 1976; Steiner, 1977; Nevo, 1976, 1978; Mitter and Futuyma, 1979; Nevo et al., 1984). These studies yielded contradictory results, partly because of the experimental design and/or the organisms compared. For example, some animal groups are physiologically more buffered than others against environmental variation, and this can affect their levels of genetic variability (Selander and Kaufman, 1973). The effect of environmental variation might be detectable only when the organisms studied are closely related and ecologically similar. In the present study, the genetic structure of several Ascaridoid worms is compared by means of multilocus electrophoresis. Evidence is given that species whose life cycle is carried out on a single homeothermic host show lower genetic variability (by a factor of about 1/3) than do those needing both poikilothermic and homeothermic hosts. Natural selection is suggested to be the major factor promoting and maintaining the different patterns of genetic variability found in these parasites. The 17 species studied belong to the superfamily Ascaridoidea; nine of them (i.e., Ascaris lumbricoides, A. suum, Parascaris univalens, P. equorum, Neoascaris vitulorum, Toxocara canis, T. cati, Toxascaris leonina, Baylisascaris transfuga) are single-host species, while eight (i.e., Anisakis simplex A, A. simplex B, A. physeteris, Phocascaris cystophorae, Contracaecum osculatum A, C. osculatum B, C. rudolphii A, C. rudolphii B) are multiple-host species. The former parasitize terrestrial mammals, whereas the latter live as larvae on poikilothermic hosts (first on crustaceans, later on fishes or squids of various size) and as adults on homeothermic hosts (marine mammals or fish-eating birds). Horizontal starch gel electrophoresis was performed on single specimens, both larvae and adults, for the following enzymes: octanol dehydrogenase (ODH), a-glycerophosphate dehydrogenase (a-GPDH), sorbitol dehydrogenase (SDH), lactate dehydrogenase (LDH), malate dehydrogenase (MDH), malic enzyme (ME), isocitrate dehydrogenase (IDH), 6-phosphogluconate dehydrogenase (6-PGDH), glucose-6-phosphate dehydrogenase (G6PDH), glyceraldheyde-3-phosphate dehydrogenase (G3PDH), xanthine dehydrogenase (XDH), superoxide dismutase (SOD), nucleoside phosphorylase (NP), glutamate oxaloacetate transaminase (GOT), hexokinase (HK), adenylate kinase (ADK), phosphoglucomutase (PGM), esterase (EST), acid phosphatase (ACPH), leucine aminopeptidase (LAP), aldolase (ALD), carbonic anhydrase (CA), triose phosphate isomerase (TPI), mannose phosphate isomerase (MPI), and glucose phosphate isomerase (GPI). The buffer systems used were: 1) tris-versene-borate (Brewer and Sing, 1970) for ODH, G6PDH, SOD, NP, CA, MPI, and GPI; 2) tris-versene-maleate (Brewer and Sing, 1970) for LDH and PGM; 3) phosphate-citrate (Harris, 1966) for a-GPDH, MDH, 6-PGDH, and ACPH; 4) discontinuous tris-citrate (Poulik, 1957) for EST and LAP; 5) continuous tris-citrate-II (Selander et al., 1971) for SDH, ME, IDH, G3PDH, XDH, GOT, HK, ADK, ALD, and TPI. The staining techniques were, with minor modifications, those described by Brewer and Sing (1970; LDH and PGM), Shaw and Prasad (1970; SDH, MDH, IDH, 6-PGDH, G6PDH, and XDH), Selander et al. (1971; SOD, GOT, and GPI), Ayala et al. (1972; ODH, a-GPDH, ME, G3PDH, HK, ADK, EST, LAP, ALD, and TPI), and Harris and Hopkinson (1976; NP, ACPH, CA, and MPI). Each species was tested for a number of loci ranging from 18 to 28, 12 of which (Ldh, Mdh-1, Idh-1, 6-Pgdh, G3pdh, Got-i, Adk-2, Pgm-1, Est-], Est-2, Mpi, and Gpi) were the same for all the species studied. The following parameters were used to estimate genetic variability: expected mean heterozygosity per locus (He); proportion of polymorphic loci, according to