| 1. |
- Kehoe, Laura, et al.
(författare)
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Make EU trade with Brazil sustainable
- 2019
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 364:6438, s. 341-
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 2. |
- Mani, Katrin, et al.
(författare)
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HIV-Tat protein transduction domain specifically attenuates growth of polyamine deprived tumor cells.
- 2007
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Ingår i: Molecular Cancer Therapeutics. - 1538-8514. ; 6:2, s. 782-788
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Tidskriftsartikel (refereegranskat)abstract
- Polyamines are essential for tumor cell growth, and the polyamine pathway represents an attractive target for cancer treatment. Several polyamine transport proteins have been cloned and characterized in bacteria and yeast cells; however, the mechanism of polyamine entry into mammalian cells remains poorly defined, although a role for proteoglycans has been suggested. Here, we show that the HIV-Tat transduction peptide, which is known to enter cells via a proteoglycan-dependent pathway, efficiently inhibits polyamine uptake. Polyamine uptake–deficient mutant cells with intact proteoglycan biosynthesis (CHO MGBG) displayed unperturbed HIV-Tat uptake activity compared with wild-type cells, supporting the notion that HIV-Tat peptide interferes with polyamine uptake via competition for proteoglycan binding sites rather than a putative downstream transporter. HIV-Tat specifically inhibited growth of human carcinoma cells made dependent on extracellular polyamines by treatment with the polyamine biosynthesis inhibitor {alpha}-difluoromethylornithine; accordingly, the Tat peptide prevented intracellular accumulation of exogenous polyamines. Moreover, combined treatment with {alpha}-difluoromethylornithine and HIV-Tat efficiently blocked tumor growth in an experimental mouse model. We conclude that HIV-Tat transduction domain and polyamines enter cells through a common pathway, which can be used to target polyamine-dependent tumor growth in the treatment of cancer.
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| 3. |
- Alavian Ghavanini, Farzan, 1978, et al.
(författare)
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A method to evaluate MEMS bonding
- 2006
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Ingår i: Micro Structure Workshop 2006. ; 1:1, s. 47-B3d
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Konferensbidrag (refereegranskat)
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| 4. |
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| 5. |
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| 6. |
- Barba, Albert, et al.
(författare)
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Osteogenesis by foamed and 3D-printed nanostructured calcium phosphate scaffolds: Effect of pore architecture
- 2018
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Ingår i: Acta Biomaterialia. - : Elsevier BV. - 1742-7061 .- 1878-7568. ; 79, s. 135-147
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Tidskriftsartikel (refereegranskat)abstract
- There is an urgent need of synthetic bone grafts with enhanced osteogenic capacity. This can be achieved by combining biomaterials with exogenous growth factors, which however can have numerous undesired side effects, but also by tuning the intrinsic biomaterial properties. In a previous study, we showed the synergistic effect of nanostructure and pore architecture of biomimetic calcium deficient hydroxyapatite (CDHA) scaffolds in enhancing osteoinduction, i.e. fostering the differentiation of mesenchymal stem cells to bone forming cells. This was demonstrated by assessing bone formation after implanting the scaffolds intramuscularly. The present study goes one step forward, since it analyzes the effect of the geometrical features of the same CDHA scaffolds, obtained either by 3D-printing or by foaming, on the osteogenic potential and resorption behaviour in a bony environment. After 6 and 12 weeks of intraosseous implantation, both bone formation and material degradation had been drastically affected by the macropore architecture of the scaffolds. Whereas nanostructured CDHA was shown to be highly osteoconductive both in the robocast and foamed scaffolds, a superior osteogenic capacity was observed in the foamed scaffolds, which was associated with their higher intrinsic osteoinductive potential. Moreover, they showed a significantly higher cell-mediated degradation than the robocast constructs, with a simultaneous and progressive replacement of the scaffold by new bone. In conclusion, these results demonstrate that the control of macropore architecture is a crucial parameter in the design of synthetic bone grafts, which allows fostering both material degradation and new bone formation. Statement of Significance 3D-printing technologies open new perspectives for the design of patient-specific bone grafts, since they allow customizing the external shape together with the internal architecture of implants. In this respect, it is important to design the appropriate pore geometry to maximize the bone healing capacity of these implants. The present study analyses the effect of pore architecture of nanostructured hydroxyapatite scaffolds, obtained either by 3D-printing or foaming, on the osteogenic potential and scaffold resorption in an in vivo model. While nanostructured hydroxyapatite showed excellent osteoconductive properties irrespective of pore geometry, we demonstrated that the spherical, concave macropores of foamed scaffolds significantly promoted both material resorption and bone regeneration compared to the 3D-printed scaffolds with orthogonal-patterned struts and therefore prismatic, convex macropores.
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| 7. |
- Barba, Albert, et al.
(författare)
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Osteoinduction by Foamed and 3D-Printed Calcium Phosphate Scaffolds : Effect of Nanostructure and Pore Architecture
- 2017
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Ingår i: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 9:48, s. 41722-41736
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Tidskriftsartikel (refereegranskat)abstract
- Some biomaterials are osteoinductive, that is, they are able to trigger the osteogenic process by inducing the differentiation of mesenchymal stem cells to the osteogenic lineage. Although the underlying mechanism is still unclear, microporosity and specific surface area (SSA) have been identified as critical factors in material-associated osteoinduction. However, only sintered ceramics, which have a limited range of porosities and SSA, have been analyzed so far. In this work, we were able to extend these ranges to the nanoscale, through the foaming and 3D-printing of biomimetic calcium phosphates, thereby obtaining scaffolds with controlled micro- and nanoporosity and with tailored macropore architectures. Calcium-deficient hydroxyapatite (CDHA) scaffolds were evaluated after 6 and 12 weeks in an ectopic-implantation canine model and compared with two sintered ceramics, biphasic calcium phosphate and β-tricalcium phosphate. Only foams with spherical, concave macropores and not 3Dprinted scaffolds with convex, prismatic macropores induced significant ectopic bone formation. Among them, biomimetic nanostructured CDHA produced the highest incidence of ectopic bone and accelerated bone formation when compared with conventional microstructured sintered calcium phosphates with the same macropore architecture. Moreover, they exhibited different bone formation patterns; in CDHA foams, the new ectopic bone progressively replaced the scaffold, whereas in sintered biphasic calcium phosphate scaffolds, bone was deposited on the surface of the material, progressively filling the pore space. In conclusion, this study demonstrates that the high reactivity of nanostructured biomimetic CDHA combined with a spherical, concave macroporosity allows the pushing of the osteoinduction potential beyond the limits of microstructured calcium phosphate ceramics.
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| 8. |
- Bartels, Pia, et al.
(författare)
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Terrestrial subsidies to lake food webs : an experimental approach
- 2012
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Ingår i: Oecologia. - New York : Springer. - 0029-8549 .- 1432-1939. ; 168:3, s. 807-818
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Tidskriftsartikel (refereegranskat)abstract
- Cross-ecosystem movements of material and energy are ubiquitous. Aquatic ecosystems typically receive material that also includes organic matter from the surrounding catchment. Terrestrial-derived (allochthonous) organic matter can enter aquatic ecosystems in dissolved or particulate form. Several studies have highlighted the importance of dissolved organic carbon to aquatic consumers, but less is known about allochthonous particulate organic carbon (POC). Similarly, most studies showing the effects of allochthonous organic carbon (OC) on aquatic consumers have investigated pelagic habitats; the effects of allochthonous OC on benthic communities are less well studied. Allochthonous inputs might further decrease primary production through light reduction, thereby potentially affecting autotrophic resource availability to consumers. Here, an enclosure experiment was carried out to test the importance of POC input and light availability on the resource use in a benthic food web of a clear-water lake. Corn starch (a C-4 plant) was used as a POC source due to its insoluble nature and its distinct carbon stable isotope value (delta C-13). The starch carbon was closely dispersed over the bottom of the enclosures to study the fate of a POC source exclusively available to sediment biota. The addition of starch carbon resulted in a clear shift in the isotopic signature of surface-dwelling herbivorous and predatory invertebrates. Although the starch carbon was added solely to the sediment surface, the carbon originating from the starch reached zooplankton. We suggest that allochthonous POC can subsidize benthic food webs directly and can be further transferred to pelagic systems, thereby highlighting the importance of benthic pathways for pelagic habitats.
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| 9. |
- Boustedt, Katarina, et al.
(författare)
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Flip chip as an enabler for MEMS packaging
- 2002
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Ingår i: 52nd Electronic Components and Technology Conference, 2002. Proceedings.. - 0780374304 ; , s. -128
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Konferensbidrag (refereegranskat)abstract
- With the recent trends in microelectronics to move more and more towards incorporating MEMS (micro electro mechanical systems) structures, lowering the overall cost becomes vital. One major cost driver in today's MEMS is the packaging. Many of the MEMS structures require some level of low pressure for full quality operation, and some may even need vacuum to function properly. Different MEMS packaging strategies exist on the market and they can be divided into two different approaches. The first one protects the wafer temporarily during wafer scribing or dicing and the second one provides a permanent seal to the wafer through full wafer bonding before scribing and dicing. The latter, permanent methods allows for selecting very low cost packaging without hermeticity as a requirement, whereas in the temporary seal methods the seal is removed after dicing and the sensitive structures become unprotected again. Using flip chip for MEMS has the benefit of providing MEMS structures with a covering lid, the chip itself. A number of flip chip MEMS interconnection methods presented in literature are described.
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| 10. |
- Boustedt, Katarina, et al.
(författare)
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Wafer Bonding Technologies for MEMS Packaging
- 2002
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Ingår i: Proceedings : the IMAPS Nordic Annual Conference : Stockholm, 2002, 29 September-2 October 2002.. - 9519800247 - 9789519800240 ; , s. -127
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 11. |
- de Moor, Joost, et al.
(författare)
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Country reports: Sweden
- 2019
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Ingår i: Protest for a future. - Bryssel : Confederation Syndicat European Trade Union. ; , s. 19-31, s. 96-111
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 12. |
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| 13. |
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| 14. |
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| 15. |
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| 16. |
- Hedsten, Karin, 1964, et al.
(författare)
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MEMS-based VCSEL beam steering using replicated polymer diffractive lens
- 2008
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Ingår i: Sensors and Actuators, A: Physical. - : Elsevier BV. - 0924-4247 .- 1873-3069. ; 142:1, s. 336-345
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Tidskriftsartikel (refereegranskat)abstract
- Abstract. This paper describes a fully integrated micro-optical system, in which dynamic angular control of the beam from a VCSEL (vertical cavity surface emitting laser) is realized by laterally moving a collimat¬ing diffractive lens in the light path. The lens is mounted on a translatable silicon stage, which consists of a frame with an opening for the light to traverse the lens and electro-statically driven comb actuators, by which the lateral movement is achieved. Devices implementing both 1D and 2D scanning have been fabricated and evaluated. Integration of the lens onto the translatable silicon stage is done using a newly developed fabrication process based on hot embossing of an amorphous fluorocarbon polymer. This fabrication process relies on a reversed-order protocol, where the structuring of the optical element precedes the silicon microstructuring. Assembly and packaging of the VCSEL-MOEMS system, using LTCC (low temperature cofired ceramic) technique, is also demonstrated. Optical evaluation of the system and beam steering function shows significant beam deflection for a relatively low driving voltage (~70 V).
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| 17. |
- Hudson, Lawrence N, et al.
(författare)
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The database of the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project
- 2017
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Ingår i: Ecology and Evolution. - : John Wiley & Sons. - 2045-7758. ; 7:1, s. 145-188
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Tidskriftsartikel (refereegranskat)abstract
- The PREDICTS project-Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)-has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.
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| 18. |
- Hudson, Lawrence N., et al.
(författare)
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The PREDICTS database : a global database of how local terrestrial biodiversity responds to human impacts
- 2014
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 4:24, s. 4701-4735
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Tidskriftsartikel (refereegranskat)abstract
- Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species' threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project - and avert - future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups - including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems - ). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.
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| 19. |
- Johander, Per, et al.
(författare)
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Layer Manufacturing as a Generic Tool for Microsystem Integration
- 2007
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Ingår i: 4M 2007, Third International Conference on Multi-Material Micro Manufacture. - 1904445535 - 9781904445531 - 1420070045 - 9781420070040
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Konferensbidrag (refereegranskat)abstract
- Nearly every microsystem application requires specific packaging solutions. In this paper we suggest a newapproach to use layer manufacturing as a generic tool for microsystem integration. Three different methods to produce3D electrical interconnects are presented. Ink jet printing is used for the ceramic layer manufacturing process, as well asfor the printing of silver for circuit patterns. The technique is demonstrated for an Inertial Measurement Unit(IMU)platform. A four-sided pyramid was manufactured with layer manufacturing in ceramics and four gyroscopes weremounted on the sides of the pyramid. A demonstrator with three light diodes was also manufactured to demonstrate thepossibility to produce 3D electrical interconnects in the volume of the pyramid.
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| 20. |
- Khan, Mohammed Faheem, et al.
(författare)
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Methods for characterization of wafer-level encapsulation applied on Si to LTCC Anodic bonding
- 2010
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Ingår i: Journal of Micromechanics and Microengineering. - : IOP Publishing. - 0960-1317 .- 1361-6439. ; 20:6
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents initial results on generic characterization methods for wafer-level encapsulation. The methods, developed specifically to evaluate anodic bonding of low-temperature cofired ceramics (LTCC) to Si, are generally applicable to wafer-level encapsulation. Different microelectromechanical system (MEMS) structures positioned over the whole wafer provide local information about the bond quality. The structures include (i) resonating cantilevers as pressure sensors for bond hermeticity, (ii) resonating bridges as stress sensors for measuring the stress induced by the bonding and (iii) frames/mesas for pull tests. These MEMS structures have been designed, fabricated and characterized indicating that local information can easily be obtained. Buried electrodes to enable localized bonding have been implemented and their effectiveness is indicated from first results of the novel Si to LTCC anodic bonding.
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| 21. |
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| 22. |
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| 23. |
- Lindström, Fredric, et al.
(författare)
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Long-term measurements of sound levels in child day-care centers
- 2010
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Ingår i: 39th International Congress on Noise Control Engineering 2010 (INTER-NOISE 2010). - : Sociedade Portuguesa de Acustica. - 9781617823961 ; , s. 2992-3001
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Konferensbidrag (refereegranskat)abstract
- Over the years numerous measurements of the sound levels in Swedish child care centers have been performed. However, most of these measurements consist of short one day measurements sessions. In this study we have measured the sound levels continuously during the whole day for several months in a row. Stationary sound level meters were used to measure the sound. In the study 6 day-care centers, with about 15 children in each, participated and for each center measurements were done in 4 different rooms, i.e. The sound levels in 24 rooms were measured continuously. Analysis of data show a wide spread between the different rooms and in time, which demonstrate the uncertainty in using single location short time, e.g. one day, measurements to assess the long-term sound levels in child day-care centers. The paper further demonstrates that long-term measurements can be used to identify e.g. differences between rooms, differences over time, etc, and that these differences can evoke questions about the activities generating them.
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| 24. |
- Löfgren, Linus, et al.
(författare)
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Low-power humidity sensor
- 2008
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Ingår i: Proceedings of Eurosensors. ; , s. 231-234
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Konferensbidrag (refereegranskat)
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| 25. |
- Löfgren, Linus, et al.
(författare)
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Low-power humidity sensor for RFID applications
- 2008
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Ingår i: 4M2008 Conference, Cardiff, UK.
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Konferensbidrag (refereegranskat)abstract
- Wireless sensors incorporated in RFID systems are important in several industrial, consumer and logisticsapplications. By extending RFID tags to sensing applications, the products become smarter. Application areas forthese smart tags include; health care (verification of the environmental conditions during transport or in storage of e.g.diapers, bandages, etc.), food monitoring (food quality during transport, storage and sales) and construction industry(e.g. building material).In this paper, a small, very low power and low cost humidity sensor tailor made for passive RFID applications ispresented. The sensor consists of a glass chip substrate with a sub-micron interdigitated gold electrode structurecovered with a humidity sensitive polyimide layer. The humidity absorbed by the sensing layer is measuredcapacitively. Finite element modeling and analytic calculations were used to determine the design of the interdigitatedelectrodes and the optimal thickness of the polyimide layer. A read-out electronics circuit was designed and used toevaluate the sensor. Sensors were fabricated and calibrations have been made to verify their function. The sensorresponse was close to linear from below 20 to above 90 %RH and its response time was proven to be at least as shortas that of the climate chamber, namely 0.1 %RH/s. The concept can easily be adapted to measure a range of otherparameters such as temperature or the presence of certain substances.
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| 26. |
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| 27. |
- Melin, Jonas, et al.
(författare)
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Microreplication in a Silicon Processing Compatible Material
- 2005
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Ingår i: IEEE/LEOS Optical MEMS 2005: International Conference on Optical MEMS and Their Applications, Oulu, Finland, 1-4 August 2005. - 9780780392786 ; , s. 89-90
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Konferensbidrag (refereegranskat)abstract
- We present a novel fabrication process for the integration of polymer micro-optical elements on silicon. The process relies on a reverse order protocol based on embossing in an amorphous fluorocarbon polymer, Cytop™.
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| 28. |
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| 29. |
- Mäger, Katrin Nele, et al.
(författare)
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Improved fire design model for walls and floors with I-joists
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Wooden I-joists, being factory-made ultra-light and highly optimised products, are typically used as the load-bearing elements in timber frame assemblies (TFA), which consist of a combination of material layers – sheeting boards (claddings) and cavities which may be partially or completely filled with insulation. The materials used in conjunction with a timber member in a TFA affect the heating of the timber member. The joists consist of flanges (made of sawn wood, LVL or glulam) and a web (made of a wood - based board). Fire resistance of such wooden structural products is a complex matter. However, the current European design standard for timber structures in fire – Eurocode 5 Part 1-2 (2004) provides no guidance for I-joists. The fire resistance of wooden I-joists has been previously investigated by König (2006) and Schmid et al. (2011), who developed calculation models to analyse the load-bearing capacity of wooden I-joists exposed to fire for floors. There have been significant changes in the variety and types of materials used in conjunction with I-joists. Therefore, the application of these models is limited nowadays. Additionally, they focus on the reduced properties method. Only the effective cross-section method will be included in the revised Eurocode 5 Part 1-2. This report describes the unified model for wooden I-joists in both wall and floor assemblies which follows the philosophy of the effective cross-section method. Additionally, it should be used with all types of cavity insulation and fire protection systems. The unified I-joists model aims to be introduced to the new revised Eurocode 5 Part 1-2. Two phenomena have to be considered according to the ECSM: charring and mechanical resistance. It is assumed that the charring of wood is a material characteristic which is not dependent on the orientation of the structure (wall or floor). The charring of the flanges is primarily dependent on the cladding material and thickness. After the failure of the claddings, the charring is influenced by cavity insulation. Gypsum plasterboards as cladding and stone and glass wool as cavity insulation have been tested and analysed. A large number of thermal simulations have been analysed to investigate the influence of various factors (e.g. flange size, cavity insulation material, protective boards) on the charring behaviour of the fire-exposed flange and the web. The combination of different materials and the slender nature of I-joists makes their fire resistance a complicated issue. The thin web is very sensitive to elevated temperatures and charring. Additionally, adhesives used in finger joints in the flanges and the joint between the flanges and the web influences the load-bearing capacity. The loss of strength and stiffness were seen in wood at elevated temperatures is considered in the ECSM by a zero-strength layer. The zero-strength layer (ZSL) is an additional reduction of the cross-section to compensate for the decrease in strength and stiffness properties. The development of the expressions to calculate the ZSL depths for compression elements is discussed in this paper.
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| 30. |
- Nielsen, Katrin, et al.
(författare)
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En kartläggning av ljudmiljön och personalhälsa i Stenungsunds förskoleklasser och årskurserna 1-3
- 2010
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Kartläggning av ljudmiljö och personalhälsa i Stenungsunds förskoleklasser och års-kurserna 1-3 är en del av ett projekt vars syfte är att på sikt förbättra innemiljö och hälsa genom minskade ljudnivåer i skolor och förskolor. En enkätundersökning utfördes bland lärare i årskurserna F-3 och förskolepersonal i hela Stenungsunds kommun. Undersökningen gjordes genom en kombination av inter-netbaserad enkät och postal enkät. Av de tillfrågade svarade 212 personer svarade på enkäten (71 % svarsfrekvens). I genomsnitt hade personalen arbetat i 15 år inom skola/förskola. Många trivdes bra eller mycket bra med sitt arbete. Det var trots det en stor andel som ansåg att det fanns förändringar som borde genomföras på arbetsplatsen. En hög andel av personalen upp-lever att de hade frihet att bestämma, men hälften upplevde stress ofta eller alltid. Bland fysiska faktorer i innemiljön besvärades klart flest av buller. Drygt hälften av personalen stördes av buller varje vecka, och ungefär lika stor andel rapporterade att de stördes ganska mycket, mycket eller oerhört mycket av buller. Buller från gap och skrik, slammer vid måltider, samtal, prat och skrap från bord och stolar rapporterades störande av en stor andel av personalen. Drygt hälften av personalen hade svårt att uppfatta samtal 25 % av arbetstiden eller mera. Störning av buller och ljud-påverkan på arbetet var relaterat till denna och andra indexfrågor om ljudnivån. Av intresse var också att nästan hälften av personalen endast stördes något eller inte alls av buller. Flertalet av personalen ansåg att deras hälsa var bra eller mycket bra. Symptom som trötthet, trött i öronen och ljudtrötthet rapporterades dock förekomma ofta av mer än hälften av de som svarat. Besvarade symptom klassificerades i kategorier: mental trött-het, hörseltrötthet, rösttrötthet och värk. Störning av buller var signifikant korrele¬rat till kategorierna mental trötthet, hörseltrötthet och rösttrötthet. Mental trötthet och hörseltrötthet var också korrelerat till innemiljöfaktorn buller. Mental trötthet och rösttrötthet var förutom bullerstörning även relaterat till flera psykosociala och arbets-organisatoriska faktorer. Buller i förskolan är ett problem i många kommuner. Denna studie visar att buller i förskolan/skolan är ett väsentligt arbets¬miljöproblem även i Stenungsunds kommun. Förekomsten av besvär vilka kan sammanfattas inom kategorierna mental trötthet, hörseltrötthet och rösttrötthet har en tydlig koppling till expone¬ring för starka och störande ljud och en sänkning av ljudnivåerna och en ökad andel återhämtningstid med lägre ljudnivå är en viktig åtgärd för en bättre arbetsmiljö.
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| 31. |
- Olofsson, Robert, et al.
(författare)
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Large-scale fire tests of engineered wood systems
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report presents the four large-scale fire tests performed within the FIRENWOOD project. The aim of the tests was to verify the improved fire design models for the I-joists and crosslaminated timber. The results of the loaded floor test with cross-laminated timber were also compared with results from an unloaded model-scale test with similar lamella thicknesses and adhesive. The aim of the compartment fire test was to study the behaviour of I-joists in physically based fire compared to the behaviour in standard fire. The second aim was to compare the fire behaviour of the compartment made of timber frame assemblies with I-joists and the previously performed similar compartments made with CLT. All large-scale tests reported here were performed with engineered wood structures using adhesive No.9
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| 32. |
- Olofsson, Robert, et al.
(författare)
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Loaded fire tests with I-joists
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The aim of the tests was to evaluate the potential reduction of the moment capacity of I-joists caused by bondline integrity of the finger joints. Each I-joist was made with 11 different adhesives in the finger joints in tension flange. All the adhesives were from Firenwood selection. Finger joints in tension may show a lower load-bearing capacity in the fire situation depending of the bond line integrity in fire. I-joists were loaded in bending with the tension flange being closer to the fire. I-joists were protected with gypsum plasterboard during the entire fire test. Cavities of the test assembly were filled with stone wool.
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| 33. |
- Persson, Andrea, et al.
(författare)
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Fine-tuning the structure of glycosaminoglycans in living cells using xylosides
- 2018
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Ingår i: Glycobiology. - : Oxford University Press (OUP). - 0959-6658 .- 1460-2423. ; 28:7, s. 499-511
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Tidskriftsartikel (refereegranskat)abstract
- Xylosides can induce the formation and secretion of xyloside-primed glycosaminoglycans when administered to living cells; however, their impact on the detailed glycosaminoglycan structure remains unknown. Here, we have systematically investigated how the xyloside concentration and the type of xyloside, as well as the cell type, influenced the structure of xyloside-primed glycosaminoglycans in terms of the heparan sulfate and chondroitin/dermatan sulfate proportion and disaccharide composition. We found that although greatest influence was exerted by the cell type, both the xyloside concentration and type of xyloside impacted the proportion of heparan sulfate and the complexity of chondroitin/dermatan sulfate. The disaccharide composition of the chondroitin/dermatan sulfate was influenced by the xyloside concentration and type of xyloside to a higher extent than that of the heparan sulfate; the proportion of 4S-sulfated disaccharides in the chondroitin/dermatan sulfate decreased and the proportions of 6S-sulfated and/or nonsulfated disaccharides increased both with increasing concentrations of xyloside and with increasing xyloside hydrophobicity, whereas the proportion of nonsulfated disaccharides was primarily altered in the heparan sulfate with increasing concentrations of xyloside. Our results indicate that it is feasible to not only produce large amounts of glycosaminoglycans in living cells but also to fine-tune their structures by using xylosides of different types and at different concentrations.
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| 34. |
- Persson, Andrea, et al.
(författare)
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LC-MS/MS characterization of xyloside-primed glycosaminoglycans with cytotoxic properties reveals structural diversity and novel glycan modifications
- 2018
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Ingår i: Journal of Biological Chemistry. - 0021-9258. ; 293:26, s. 10202-10219
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Tidskriftsartikel (refereegranskat)abstract
- Structural characterization of glycosaminoglycans remains a challenge but is essential for determining structure-function relationships between glycosaminoglycans and the biomolecules with which they interact and for gaining insight into the biosynthesis of glycosaminoglycans. We have recently reported that xyloside-primed chondroitin/dermatan sulfate derived from a human breast carcinoma cell line, HCC70, has cytotoxic effects and shown that it differs in disaccharide composition from nontoxic chondroitin/dermatan sulfate derived from a human breast fibroblast cell line, CCD-1095Sk. To further investigate the structural requirements for the cytotoxic effect, we developed a novel LC-MS/MS approach based on reversed-phase dibutylamine ion-pairing chromatography and negative-mode higher-energy collision dissociation and used it in combination with cell growth studies and disaccharide fingerprinting. This strategy enabled detailed structural characterization of linkage regions, internal oligosaccharides, and nonreducing ends, revealing not only differences between xyloside-primed chondroitin/dermatan sulfate from HCC70 cells and CCD-1095Sk cells, but also sialylation of the linkage region and previously undescribed methylation and sulfation of the nonreducing ends. Although the xyloside-primed chondroitin/dermatan sulfate from HCC70 cells was less complex in terms of presence and distribution of iduronic acid than that from CCD-1095Sk cells, both glucuronic acid and iduronic acid appeared to be essential for the cytotoxic effect. Our data have moved us one step closer to understanding the structure of the cytotoxic chondroitin/dermatan sulfate from HCC70 cells primed on xylosides and demonstrate the suitability of the LC-MS/MS approach for structural characterization of glycosaminoglycans.
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| 35. |
- Persson, Andrea, et al.
(författare)
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Production and HPLC-Based Disaccharide Analysis of Xyloside-Primed Glycosaminoglycans
- 2022
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Ingår i: Glycosaminoglycans. Methods in Molecular Biology, vol 2303. Balagurunathan K., Nakato H., Desai U., Saijoh Y. (eds). - New York, NY : Springer. - 1064-3745 .- 1940-6029. - 9781071613986 ; , s. 173-182
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Although glycosaminoglycans (GAGs) are known to be involved in a variety of physiological and pathological processes, knowledge about their expression by cells or tissues, the GAGome, is limited. Xylosides can be used to induce the formation of GAGs without the presence of a proteoglycan core protein. The administration of xylosides to living cells tends to result in a considerable amplification in GAG production, and the xylosides can, therefore, be used as analytical tools to study the GAG produced by a certain cell type. One of the most common ways to analyze the GAGs structurally is by disaccharide analysis, which involves depolymerization of the GAGs into disaccharides, fluorescent labeling of the disaccharides with 2-aminoacridone, and quantification using high-pressure liquid chromatography (HPLC). Here, we describe the procedure of producing xyloside-primed GAGs and how to study them structurally by disaccharide analysis. © 2022, Springer Science+Business Media, LLC, part of Springer Nature.
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| 36. |
- Persson, Andrea, et al.
(författare)
-
Xyloside-primed chondroitin sulfate/dermatan sulfate from breast carcinoma cells with a defined disaccharide composition has cytotoxic effects in vitro
- 2016
-
Ingår i: Journal of Biological Chemistry. - 1083-351X. ; 291:28, s. 14871-14882
-
Tidskriftsartikel (refereegranskat)abstract
- We have previously reported that the xyloside 2-(6-hydroxynaphthyl) β-D-xylopyranoside (XylNapOH), in contrast to 2-naphthyl β-D-xylopyranoside (XylNap), specifically reduces tumor growth both in vitro and in vivo. Although there are indications that this could be mediated by the xyloside-primed glycosaminoglycans (GAGs) and that these differ in composition depending on xyloside and cell type, detailed knowledge regarding a structure-function relationship is lacking. In this study, we isolated XylNapOH- and XylNap-primed GAGs from a breast carcinoma cell line, HCC70, and a breast fibroblast cell line, CCD-1095Sk, and demonstrated that both XylNapOH- and XylNap-primed chondroitin sulfate/dermatan sulfate (CS/DS) GAGs derived from HCC70 cells had a cytotoxic effect on HCC70 cells and CCD-1095Sk cells. The cytotoxic effect appeared to be mediated by induction of apoptosis and was inhibited in a concentration-dependent manner by the XylNap-primed heparan sulfate (HS) GAGs. In contrast, neither the CS/DS nor the HS derived from CCD-1095Sk cells primed on XylNapOH or XylNap had any effect on the growth of HCC70 cells or CCD-105Sk cells. These observations were related to the disaccharide composition of the XylNapOH- and XylNap-primed GAGs, which differed considerably between the two cell lines, but was similar when the GAGs were derived from the same cell line. To our knowledge, this is the first report on cytotoxic effects mediated by CS/DS.
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| 37. |
- Persson, Inger, et al.
(författare)
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Confirming the Structure of the Survey of Attitudes Toward Statistics (SATS-36) by Swedish Students
- 2019
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Ingår i: Statistics Education Research Journal. - : International Association for Statistical Education. - 1570-1824. ; 18:1, s. 83-93
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Tidskriftsartikel (refereegranskat)abstract
- Research on students’ attitudes toward statistics has attracted many statistics instructors and statistics education researchers. In this study, we use confirmatory factor analysis to analyze data collected from an introductory statistics course using the Survey of Attitudes toward Statistics. Theresults suggest that the items and six factors are conceptually relevant, confirming the six-factor structure of the pretest version of SATS-36 on this sample of Swedish students, with a few suggested modifications of the original model structure. Two items are excluded from the Difficulty component, two items on the Affect component are allowed to correlate, and two items on the Cognitive competence component are also allowed to correlate.
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| 38. |
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| 39. |
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| 40. |
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| 41. |
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| 42. |
- Schröder, Stephan, 1979-, et al.
(författare)
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Stress-minimized packaging of inertial sensors using wire bonding
- 2013
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Ingår i: 2013 Transducers and Eurosensors XXVII. - : IEEE conference proceedings. - 9781467359818 - 9781467359832 ; , s. 1962-1965
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Konferensbidrag (refereegranskat)abstract
- This paper presents a packaging approach for inertial sensors using wire bonding technology. The die is mounted exclusively by bond wires on the front- and backside to the package. Conventional single-side die attach to substrates, such as gluing, is abandoned. The approach is characterized by its novel and symmetric die attach concept as well as its simplicity of applying a standard wire bonding process. The wire bond attachment facilitates significant reduction of thermally induced mechanical stresses. The attachment concept is characterized in terms of attachment stiffness and potential die resonances using Laser Doppler Vibrometry (LDV). White-light interferometry is used to investigate stress related warping that is induced by the die attachment process.
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| 43. |
- Siegbahn, Anna, et al.
(författare)
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Exploration of the active site of beta 4GalT7 : modifications of the aglycon of aromatic xylosides
- 2015
-
Ingår i: Organic and biomolecular chemistry. - : Royal Society of Chemistry (RSC). - 1477-0520 .- 1477-0539. ; 13:11, s. 3351-3362
-
Tidskriftsartikel (refereegranskat)abstract
- Proteoglycans (PGs) are macromolecules that consist of long linear polysaccharides, glycosaminoglycan (GAG) chains, covalently attached to a core protein by the carbohydrate xylose. The biosynthesis of GAG chains is initiated by xylosylation of the core protein followed by galactosylation by the galactosyltransferase beta 4GalT7. Some beta-D-xylosides, such as 2-naphthyl beta-D-xylopyranoside, can induce GAG synthesis by serving as acceptor substrates for beta 4GalT7 and by that also compete with the GAG synthesis on core proteins. Here we present structure-activity relationships for beta 4GalT7 and xylosides with modifications of the aromatic aglycon, using enzymatic assays, cell studies, and molecular docking simulations. The results show that the aglycons reside on the outside of the active site of the enzyme and that quite bulky aglycons are accepted. By separating the aromatic aglycon from the xylose moiety by linkers, a trend towards increased galactosylation with increased linker length is observed. The galactosylation is influenced by the identity and position of substituents in the aromatic framework, and generally, only xylosides with beta-glycosidic linkages function as good substrates for beta 4GalT7. We also show that the galactosylation ability of a xyloside is increased by replacing the anomeric oxygen with sulfur, but decreased by replacing it with carbon. Finally, we propose that reaction kinetics of galactosylation by beta 4GalT7 is dependent on subtle differences in orientation of the xylose moiety.
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| 44. |
- Siegbahn, Anna, et al.
(författare)
-
Exploration of the active site of β4GalT7: modifications of the aglycon of aromatic xylosides.
- 2015
-
Ingår i: Organic and Biomolecular Chemistry. - : Royal Society of Chemistry (RSC). - 1477-0539 .- 1477-0520. ; 13:11, s. 3351-3362
-
Tidskriftsartikel (refereegranskat)abstract
- Proteoglycans (PGs) are macromolecules that consist of long linear polysaccharides, glycosaminoglycan (GAG) chains, covalently attached to a core protein by the carbohydrate xylose. The biosynthesis of GAG chains is initiated by xylosylation of the core protein followed by galactosylation by the galactosyltransferase β4GalT7. Some β-d-xylosides, such as 2-naphthyl β-d-xylopyranoside, can induce GAG synthesis by serving as acceptor substrates for β4GalT7 and by that also compete with the GAG synthesis on core proteins. Here we present structure-activity relationships for β4GalT7 and xylosides with modifications of the aromatic aglycon, using enzymatic assays, cell studies, and molecular docking simulations. The results show that the aglycons reside on the outside of the active site of the enzyme and that quite bulky aglycons are accepted. By separating the aromatic aglycon from the xylose moiety by linkers, a trend towards increased galactosylation with increased linker length is observed. The galactosylation is influenced by the identity and position of substituents in the aromatic framework, and generally, only xylosides with β-glycosidic linkages function as good substrates for β4GalT7. We also show that the galactosylation ability of a xyloside is increased by replacing the anomeric oxygen with sulfur, but decreased by replacing it with carbon. Finally, we propose that reaction kinetics of galactosylation by β4GalT7 is dependent on subtle differences in orientation of the xylose moiety.
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| 45. |
- Siegbahn, Anna, et al.
(författare)
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Rules for priming and inhibition of glycosaminoglycan biosynthesis; probing the beta 4GalT7 active site
- 2014
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Ingår i: Chemical Science. - : Royal Society of Chemistry (RSC). - 2041-6520 .- 2041-6539. ; 5:9, s. 3501-3508
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Tidskriftsartikel (refereegranskat)abstract
- beta-1,4-Gatactosyltransferase 7 (beta 4GalT7) is an essential enzyme in the biosynthesis of glycosaminoglycan (GAG) chains of proteoglycans (PGs). Mammalian cells produce PGs, which are involved in biological processes such as cell growth and differentiation. The PGs consist of a core protein, with one or several GAG chains attached. Both the structure of the PGs and the GAG chains, and the expression of the enzymes involved in their biosynthesis and degradation, vary between normal cells and tumor cells. The biosynthesis of GAG chains is initiated by xylosylation of a serine residue of the core protein, followed by galactosylation by beta 4GalT7. The biosynthesis can also be initiated by exogenously added beta-D-xylopyranosides with hydrophobic aglycons, which thus can act as acceptor substrates for beta 4GalT7. To determine the structural requirements for beta 4GalT7 activity, we have cloned and expressed the enzyme and designed a focused library of 2-naphthyl beta-D-xylopyranosides with modifications of the xylose moiety. Based on enzymatic studies, that is galactosylation and its inhibition, conformational analysis and molecular modeling using the crystal structure, we propose that the binding pocket of beta 4GalT7 is very narrow, with a precise set of important hydrogen bonds. Xylose appears to be the optimal acceptor substrate for galactosylation by beta 4GalT7. However, we show that modifications of the xylose moiety of the beta-D-xylopyranosides can render inhibitors of galactosylation. Such compounds will be valuable tools for the exploration of GAG and PG biosynthesis and a starting point for development of anti-tumor agents.
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| 46. |
- Skogvall, Staffan, et al.
(författare)
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Discovery of a potent and long-acting bronchorelaxing capsazepinoid, RESPIR 4-95
- 2008
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Ingår i: Pulmonary Pharmacology & Therapeutics. - : Elsevier BV. - 1522-9629 .- 1094-5539. ; 21:1, s. 125-133
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Current drugs including beta-agonists have limited smooth muscle relaxant effects on human small airways. Yet this is a major site of obstruction in asthma and chronic obstructive pulmonary disease (COPD). OBJECTIVE: This study explores human small airway relaxant effects of RESPIR 4-95, a novel chemical analogue (capsazepinoid) to capsazepine. Capsazepine was recently shown to relax small airways in a way which was independent of its TRPV(1) antagonism and independent of current bronchodilator drug mechanisms. METHOD: In vitro preparations of human small airways, 0.5-1.5mm in diameter and responding with reproducible contractions to leukotriene D(4) (LTD(4)) for 12h, were used. RESULTS: RESPIR 4-95 reversibly prevented LTD(4)-induced contractions as well as relaxed the established tonic contraction by LTD(4). RESPIR 4-95 exhibited marked improvements over the reference capsazepinoid, capsazepine, by being 10 times more potent, exhibiting twice as long duration of action after wash-out (9h), and inhibiting equally well LTD(4)-, histamine-, prostaglandin D(2) (PGD(2))-, and acetylcholine (ACh)-induced contractions. RESPIR 4-95 was distinguished from l-type calcium channel antagonist nifedipine by its greater efficacy and potency and by exhibiting increased relaxant effect by repeated exposures. Furthermore, RESPIR 4-95 was more efficacious and longer acting than the long-acting beta-agonist formoterol. CONCLUSION: Efficacy, potency, duration of action, and inexhaustibility of its relaxation of human small airways make RESPIR 4-95 an interesting lead compound for further developments aiming at drug treatment of small airway obstruction in asthma and COPD. Further work is warranted to unveil the molecular biology behind its relaxant actions.
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| 47. |
- Skogvall, Staffan, et al.
(författare)
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Effects of capsazepine on human small airway responsiveness unravel a novel class of bronchorelaxants.
- 2007
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Ingår i: Pulmonary Pharmacology & Therapeutics. - : Elsevier BV. - 1522-9629 .- 1094-5539. ; 20, s. 273-280
-
Tidskriftsartikel (refereegranskat)abstract
- Capsazepine is known as a transient receptor potential channel vanilloid subfamily 1 (TRPV1) antagonist that inhibits bronchoconstriction evoked in animals by TRPV1 agonists. In this study, effects of capsazepine and chemically related analogues, so called capsazepinoids, were examined in vitro on contractile effects in human small airway preparations. Repeated cycles with 1 h of LTD4-free physiological saline solution followed by 30 min exposure to LTD4 (10 nM) demonstrated that the contractile responsiveness of the preparations exhibited little change over time despite repeated challenges (> 12 h). Capsazepine (1-100 mu M) reversibly and concentration-dependently inhibited the contractile response to LTD4 with EC50 similar to 10 mu M and similar to 90% relaxation at 100 mu M. Capsazepine (10 M) was approximately equally effective to attenuate the contractions evoked by several different inflammatory contractile agonists (LTD4, PGD(2), histamine), and it relaxed preparations with established tonic contraction due to LTD4. Higher concentrations of capsazepine were needed to relax ACh-contractions. The effect of capsazepine on LTD4-induced contractions was not significantly reduced by pre-treating the preparations with either of propranotol (10 mu M) + atropine (1 mu M), L-NAME (1 mM), indomethacin (1 mu M), iberiotoxin (0.1 mu M), capsaicin (10 mu M), and nifedipine (10 mu M). Although the mechanism of action of the present capsazepine-induced bronchorelaxation remains unknown it emerged here that they represent a generally effective principle exerting a functional antagonism against contractile mediators but distinct from beta receptor agonists and inhibitors of L-type calcium channels. The inhibitory effect of capsazepine is shared by chemical analogues, but not with other TRPV1 antagonists, suggesting the possibility that capsazepine represents a novel class of bronchorelaxants effective in human small airways. These findings were not predicted by previous observations that have concerned quite limited effects of capsazepine on airway tone in different animal test systems. If potency can be further increased and the results translated to in vivo, compounds representing the capsazepinoid class of bronchorelaxants might become useful in the treatment of patients suffering from asthma and COPD.
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| 48. |
- Svensson, Katrin, et al.
(författare)
-
Hypoxia-mediated induction of the polyamine system provides opportunities for tumor growth inhibition by combined targeting of vascular endothelial growth factor and ornithine decarboxylase.
- 2008
-
Ingår i: Cancer Research. - 1538-7445. ; 68:22, s. 9291-9301
-
Tidskriftsartikel (refereegranskat)abstract
- Hypoxia is a hallmark of solid tumors, which may offer opportunities for targeted therapies of cancer; however, the mechanisms that link hypoxia to malignant transformation and tumor progression are not fully understood. Here, we show that up-regulation of the polyamine system promotes cancer cell survival during hypoxic stress. Hypoxia was found to induce polyamine transport and the key enzyme of polyamine biosynthesis, ornithine decarboxylase (ODC), in a variety of cancer cell lines. Increased ODC protein expression was shown in hypoxic, GLUT-1-expressing regions of tumor spheroids and experimental tumors, as well as in clinical tumor specimens. Hypoxic induction of the polyamine system was dependent on antizyme inhibitor (i.e., a key positive regulator of ODC and polyamine transport), as shown by RNA interference experiments. Interestingly, depletion of the polyamines during hypoxia resulted in increased apoptosis, which indicates an essential role of the polyamines in cancer cell adaptation to hypoxic stress. These results were supported by experiments in an in vivo glioma tumor model, showing significantly enhanced antitumor effects of the antiangiogenic, humanized anti-vascular endothelial growth factor (VEGF) antibody bevacizumab when used in combination with the well-established, irreversible inhibitor of ODC, alpha-difluoromethylornithine. Our results provide important insights into the hypoxic stress response in malignant cells and implicate combined targeting of VEGF and ODC as an alternative strategy to treat cancer disease.
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| 49. |
- Thorsheim, Karin, et al.
(författare)
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Disubstituted naphthyl β-D-xylopyranosides : Synthesis, GAG priming, and histone acetyltransferase (HAT) inhibition
- 2016
-
Ingår i: Glycoconjugate Journal. - : Springer Science and Business Media LLC. - 1573-4986 .- 0282-0080. ; 33:2, s. 57-245
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Tidskriftsartikel (refereegranskat)abstract
- Xylosides are a group of compounds that can induce glycosaminoglycan (GAG) chain synthesis independently of a proteoglycan core protein. We have previously shown that the xyloside 2-(6-hydroxynaphthyl)β-D-xylopyranoside has a tumor-selective growth inhibitory effect both in vitro and in vivo, and that the effect in vitro was correlated to a reduction in histone H3 acetylation. In addition, GAG chains have previously been reported to inhibit histone acetyltransferases (HAT). To investigate if xylosides, or the corresponding xyloside-primed GAG chains, can be used as HAT inhibitors, we have synthesized a series of naphthoxylosides carrying structural motifs similar to the aromatic moieties of the known HAT inhibitors garcinol and curcumin, and studied their biological activities. Here, we show that the disubstituted naphthoxylosides induced GAG chain synthesis, and that the ones with at least one free phenolic group exhibited moderate HAT inhibition in vitro, without affecting histone H3 acetylation in cell culture. The xyloside-primed GAG chains, on the other hand, had no effect on HAT activity, possibly explaining why the effect of the xylosides on histone H3 acetylation was absent in cell culture as the xylosides were recruited for GAG chain synthesis. Further investigations are required to find xylosides that are effective HAT inhibitors or xylosides producing GAG chains with HAT inhibitory effects.
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| 50. |
- Thorsheim, Karin, et al.
(författare)
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Synthesis and biology of oligoethylene glycol linked naphthoxylosides.
- 2013
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Ingår i: Bioorganic & Medicinal Chemistry. - : Elsevier BV. - 0968-0896. ; 21:11, s. 3310-3317
-
Tidskriftsartikel (refereegranskat)abstract
- Proteoglycans (PGs) are important macromolecules in mammalian cells, consisting of a core protein substituted with carbohydrate chains, known as glycosaminoglycans (GAGs). Simple xylosides carrying hydrophobic aglycons can enter cells and act as primers for GAG chain synthesis, independent of the core protein. Previously it has been shown that aromatic aglycons can be separated from the sugar residue by short linkers without affecting the GAG priming ability. To further investigate the effects of the xylose-aglycon distance on the GAG priming ability, we have synthesized xyloside derivatives with 2-naphthyl and 2-(6-hydroxynaphthyl) moieties connected to xylose, directly, via a methylene bridge, or with oligoethylene glycol linkers of three different lengths. The GAG priming ability and the antiproliferative activity of the xylosides, as well as the composition of the xyloside-primed GAG chains were investigated in a matched pair of human breast fibroblasts and human breast carcinoma cells. An increase of the xylose-aglycon distance from 0.24 to 0.37nm resulted in an increased GAG priming ability in both cell lines. Further increase of the xylose-aglycon distance did not result in any pronounced effects. We speculate that by increasing the xylose-aglycon distance, and thereby the surface area of the xyloside, to a certain level would make it more accessible for enzymes involved in the GAG synthesis. The compositions of the primed GAG chains varied with different xylosides, independent of the xylose-aglycon distance, probably due to various affinities for enzymes and/or different cellular uptake. Furthermore, no correlations between the antiproliferative activities, the xylose-aglycon distances, and the amounts or compositions of the GAG chains were detected suggesting involvement of other factors such as fine structure of the GAG chains, effects on endogenous PG synthesis, or other unknown factors for the antiproliferative activity.
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