| 1. |
- Bilger, R, et al.
(författare)
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Cross sections of the pp -> pp pi(0) reaction between 310 and 425 MeV
- 2001
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Ingår i: NUCLEAR PHYSICS A. - : ELSEVIER SCIENCE BV. - 0375-9474. ; 693:3-4, s. 633-662
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Tidskriftsartikel (refereegranskat)abstract
- Extensive kinematically complete measurements of the pp --> pp pi (0) reaction have been made at six beam energies: 310, 320, 340, 360, 400, and 425 MeV. Angles and energies of both final-state protons are extracted from the forward detector system of the
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| 2. |
- Zoucas, E., et al.
(författare)
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Inhibition of platelet aggregation by granulocytes stimulated during experimental trauma
- 1990
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Ingår i: Critical Care Medicine. - : Ovid Technologies (Wolters Kluwer Health). - 0090-3493. ; 18:8, s. 845-847
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Tidskriftsartikel (refereegranskat)abstract
- The effect of granulocytes, stimulated in vivo by standardized soft tissue trauma, on the aggregation of autologous platelets in vitro, was studied in the pig. Platelet aggregation induced by ADP and arachidonic acid was inhibited when platelets harvested before trauma were incubated with granulocytes obtained 5 min after trauma. The granulocytes were separated from the platelets during the incubation by enclosure in dialysis tubes. Platelet inhibition was evident when the cell cohorts were suspended in cell-free medium as well as in autologous plasma extracted before trauma. In addition, incubation of platelets harvested before trauma with plasma obtained after trauma decreased platelet aggregation. In conclusion, granulocytes stimulated in vivo inhibited platelet function in vitro. Platelet inhibitory activity was shown to be related with the granulocytes per se, but also with factors present in plasma after trauma.
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| 3. |
- Eriksson, M., et al.
(författare)
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Determination of hydrocarbons in old creosote contaminated soil using headspace solid phase microextraction and GC-MS
- 2001
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Ingår i: Chemosphere. - 0045-6535 .- 1879-1298. ; 44:7, s. 1641-1648
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Tidskriftsartikel (refereegranskat)abstract
- Headspace solid phase microextraction (HS-SPME) has been used together with GC-MS to analyze organic substances directly in a soil, heavily contaminated with PAHs/creosote (similar to 300 mg/kg soil), from an old gaswork site in Stockholm, Sweden. The HS-SPME results, both qualitative and quantitative, were compared with traditional liquid extraction using ethyl acetate/hexane (20:80). It was shown that the concentrations determined with HS-SPME at 60 degreesC correlated well, for compounds containing up to two and three aromatic rings (naphthalenes, acenaphthene, acenaphthylene and fluorenes, while a lower concentration was obtained for phenanthrene, anthracene, fluoranthene and pyrene. The total concentrations for each compound determined with HS-SPME ranged from 2 to 25 mug/g soil. Quantification was done using standard addition of compounds directly to the soil samples. The bioavailable fraction of the compounds in the contaminated soil at 20 degreesC was analyzed using external calibration by spiking sterile uncontaminated sand (same texture and particle size as the contaminated soil but without a heavily sorbed organic fraction) with hydrocarbon standards in different concentrations. Storage of exposed fibers at 20 degreesC showed that analysis should be done within two days to make qualitative measurements and earlier (as soon as possible) for quantitative determinations.
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| 4. |
- Faldt, J., et al.
(författare)
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Comparison of headspace techniques for sampling volatile natural products in a dynamic system
- 2000
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Ingår i: Zeitschrift für Naturforschung C - A Journal of Biosciences. - : Walter de Gruyter GmbH. - 0939-5075 .- 1865-7125. ; 55:04-mar, s. 180-188
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Tidskriftsartikel (refereegranskat)abstract
- Commonly used dynamic sorption techniques for collecting biologically active volatile compounds have been compared. Solid phase microextraction (SPME) using two types of fibers (polydimethylsiloxane, PDMS, 100 mu m, and carbowax/divinylbenzene, CW/DVB, 65 mu m) was compared to purge and trap methods (Porapak Q, Tenax TA and charcoal) and a technique based on absorption in methanol in a cooling bath. Sampling was done in a stream of purified air (20 ml/min) in a closed and temperature-regulated (27 degrees C) glass tube, passing over a capillary tube containing a hexane solution of tridecane, heptadecane, 1-octen-3-ol, 1-hexadecanol, ethyl tetradecanoate, alpha-pinene, linalool, terpinen-4-ol, cis-verbenol, verbenone, beta-caryophyllene, E,E-farnesol, and geranylgeraniol. With all of the methods, the sampling was performed for a period of 30 min before extraction and analysis was done on a GC-FID system. In general, SPME gave a higher response for all compounds except for alpha-pinene, which was only extracted by the CW/DVB fiber. Purge and trap methods and methanol absorption gave the same response for all substances extracted. None of the methods extracted hexadecanol and geranylgeraniol under the conditions used. However, the SPME equipped with the PDMS coating extracted heptadecane, E,E-farnesol and ethyl tetradecanoate. Our results show that SPME, when selecting the fibers to fit the polarity and volatility of the compounds, is an outstanding extraction method compared to purge and trap and methanol absorption, especially for a qualitative analysis. The best conditions for storing fibers exposed to compounds of high volatility were at low temperatures (6 degrees C) in sealed vials, while the worst way was to leave the exposed fiber unprotected at room temperature (22 degrees C). The dynamic sampling system was effectively tested on a fruiting body of a polypore fungus (Ganoderma applanatum) emitting 1-octen-3-ol, and again SPME showed to be the most sensitive technique.
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| 5. |
- Faldt, J., et al.
(författare)
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Correlations between selected monoterpene hydrocarbons in the xylem of six Pinus (pinaceae) species
- 2001
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Ingår i: Chemoecology. - 0937-7409 .- 1423-0445. ; 11:2, s. 97-106
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Tidskriftsartikel (refereegranskat)abstract
- The compositions of 23 monoterpene hydrocarbons of six pine species (Pinus sylvestris, P. yunnanensis ll,ris, P. armandii, P. tropicalis, P. cubensis and P. caribaca) were compared, using multivariate data analysis. Four of the six species were clearly different from the other species in a Principal Components Analysis (PCA) model, based on the relative amounts (selective normalization) of the monoterpenes. The correlation coefficients between constituents were determined separately for each species and the strongest correlations were found between (+)-alpha -pinene and (+)-camphene and between the corresponding (-)-enantiomers, in all species. This pattern, i.e. a good correlation in all species, was neither shown by the correlation of the structurally more similar (+)-alpha/beta -pinenes, nor by the (-)-alpha/beta -pinenes or within the enantiomeric pairs of alpha -pinene and beta -pinene. For these pairs of monoterpenes, good correlations were found in some species. None of the species showed good correlations in all the investigated monoterpene pairs presented here. Correlations between monoterpenes in insect-attacked trees (P. cubensis and P. caribaea, attacked by Dioryctria horneana, and P. yunnanensis, attacked by Tomicus piniperda) were also determined. The results are discussed from chemotaxonomic and biosynthetic points of view.
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| 6. |
- Faldt, R., et al.
(författare)
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Heat production in different populations of human blood cells exposed to immune complexes in vitro : The importance of the Fc parts of immunoglobulins and the influence of active complement
- 1982
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Ingår i: Immunology. - 0019-2805. ; 46:1, s. 189-198
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Tidskriftsartikel (refereegranskat)abstract
- By use of a batch microcalorimeter of the thermopile type, heat production was measured in isolated populations of human peripheral blood cells exposed to defined immune complexes formed in vitro. It was found that most of the heat production recorded in whole blood after admixture of immune complexes occurs in the granulocytes. Under these conditions small but constantly higher activation values were found in the absence of active complement. It was shown that complexes consisting of antigen and F(ab)2 fragments prepared from the specific antibodies were able to initiate heat production in the cells only in the presence of active complement. These experiments indicate that immune complexes are able to induce increased heat production in the cells either by binding to Fc receptors or by activation of complement through the alternative pathway and subsequent binding of the generated C3b to C3b receptors on the heat-producing cells.
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| 7. |
- Faldt, R., et al.
(författare)
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Heat production rate in polymorphonuclear granulocytes from patients with acute myelogenous leukaemia and healthy individuals
- 1984
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Ingår i: British Journal of Haematology. - : Wiley. - 0007-1048 .- 1365-2141. ; 58:4, s. 671-678
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Tidskriftsartikel (refereegranskat)abstract
- Heat production rate in polymorphonuclear granulocytes (PMN) from 18 AML patients and 21 healthy individuals was measured using microcalorimetry. An increased PMN heat production rate was found in most AML patients at diagnosis and during the first 6 months of remission. In 7/7 patients showing values above the normal mean level the heat production rate decreased during sequential analysis. The increased PMN heat production rate is serum dependent and leukaemic sera induced increased calorimetric values also in PMN from healthy donors. This effect was not due to heat labile complement factors.
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| 8. |
- Johansson, R, et al.
(författare)
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Measurement of the exclusive D(p,e(+)e(-))He-3 and D(p,gamma)He-3 reactions at 98 and 176 MeV
- 1998
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Ingår i: NUCLEAR PHYSICS A. - : ELSEVIER SCIENCE BV. - 0375-9474. ; 641:4, s. 389-400
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Tidskriftsartikel (refereegranskat)abstract
- A high resolution magnetic pair spectrometer for medium energy photons has been used for studies of the exclusive (p,e(+)e(-)) and (p, gamma) reactions on deuterium at 98 and 176 MeV. The (p, e(+)e(-)) cross sections, obtained at 40 degrees and 80 degrees
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| 9. |
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| 10. |
- Rostelien, T., et al.
(författare)
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The plant sesquiterpene germacrene D specifically activates a major type of antennal receptor neuron of the tobacco budworm moth Heliothis virescens
- 2000
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Ingår i: Chemical Senses. - : Oxford University Press (OUP). - 0379-864X .- 1464-3553. ; 25:2, s. 141-148
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Tidskriftsartikel (refereegranskat)abstract
- Plants release hundreds of volatiles that are important in interactions with insects or other organisms. However, knowledge is scarce as to which of the compounds are detected by the organism's olfactory receptor neurons. In the present study, single receptor neurons on the antennae of the tobacco budworm moth, Heliothis virescens, were screened far their sensitivities to naturally produced plant volatiles by the use of gas chromatography linked to electrophysiological recordings from single cells (GC-SCR). Plant volatiles, collected by aeration of host and non-host plants, were tested on each receptor neuron via parallel GC-columns. Thus, simultaneous recordings of the gas chromatogram and the neuron responses to each component were obtained. One type of receptor neuron, appearing in 80% of all experiments, responded with high sensitivity and selectivity to one particular component, present in host as well as non-host mixtures. The component, identified as a sesquiterpene hydrocarbon by linked gas chromatography-mass spectrometry, was isolated from a sesquiterpene fraction of cubebe oil and identified by NMR as germacrene D. The purified compound was then re-tested via gas chromatography on the same receptor neuron type, verifying the identification. A weaker response to another sesquiterpene hydrocarbon was also recorded.
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