| 1. |
- Rönn, Monika, et al.
(författare)
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Bisphenol A is related to circulating levels of adiponectin, leptin and ghrelin, but not to fat mass or fat distribution in humans
- 2014
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 112, s. 42-48
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Since bisphenol A (BPA) has been shown to induce obesity in experimental studies, we explored the associations between BPA and fat mass, fat distribution and circulating levels of adiponectin, leptin and ghrelin in humans. Methods: In the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS), fat mass and fat distribution were determined in 70-year-old men and women (n = 890) by dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI) (n = 287). Serum levels of BPA were analyzed using isotope liquid chromatography/tandem mass spectrometer (API4000LC-MS/MS). Hormone levels were analyzed with radioimmunoassays (RIA) or enzyme-linked immunosorbent assay (ELISA). Imaging was performed approximately two years following collection of other data. Results: Serum concentrations of BPA were not related to adipose tissue measurements by DXA or MRI. BPA associated positively with adiponectin and leptin, but negatively with ghrelin, following adjustments for sex, height, fat mass, lean mass, smoking, alcohol consumption, physical activity, energy intake, and educational levels (p < 0.001, p = 0.009, p < 0.001, respectively). The relationship between BPA and ghrelin was stronger in women than in men. Conclusion: Although no relationships between BPA levels and measures of fat mass were seen, BPA associated strongly with the adipokines adiponectin and leptin and with the gut-hormone ghrelin suggesting that BPA may interfere with hormonal control of hunger and satiety.
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| 2. |
- Andersson, Jonas, et al.
(författare)
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Association of adipose tissue blood flow with fat depot sizes and adipokines in women
- 2012
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Ingår i: International Journal of Obesity. - : Nature Publishing Group. - 0307-0565 .- 1476-5497. ; 36:6, s. 783-789
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To explore possible associations between adipose tissue (AT) blood flow (ATBF), AT depot sizes and adipocyte-derived hormones (adipokines) in women.Subjects: In all, 43 healthy women were divided into four groups: normal-weight (n=11) and obese (n=11) pre-menopausal women and normal-weight (n=10) and obese (n=11) post-menopausal women.Methods: Fasting levels of adipokines were obtained, and a single-slice computed tomography scan at the level of L4-L5 was used to estimate fat depot sizes. ATBF was assessed by xenon washout while in a fasting state and after oral glucose load. We also measured glucose, insulin and non-esterified fatty acids.Results: Total, subcutaneous and visceral AT areas strongly correlated with ATBF (all P<0.001). Circulating leptin levels strongly and inversely correlated with ATBF (P=0.001), but this association did not remain after adjustment for body mass index. Adiponectin was not associated with blood flow.Conclusion: ATBF is closely linked to subcutaneous and visceral AT size. Further analyses are needed to determine possible mediators of this association, including mechanistic studies to assess a putative role for leptin as a significant modulator of blood flow. International Journal of Obesity advance online publication, 26 July 2011; doi:10.1038/ijo.2011.152.
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| 3. |
- Athley, Karin, et al.
(författare)
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Mechanical retention - Influence of filler floc size and grammage of the fibre web
- 2012
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Ingår i: Nordic Pulp & Paper Research Journal. - 0283-2631 .- 2000-0669. ; 27:2, s. 202-207
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Tidskriftsartikel (refereegranskat)abstract
- An investigation of the impact of particle size on the mechanical retention of particles in a fibre network has been conducted. The particles used were five sets of quartz particle fractions having fairly narrow particle size distributions with average particle size ranging from a few μm to around 100 μm. The particles were used to model flocculated filler aggregates as part of a larger study of the effect of pre-flocculation on mechanical retention. Pre-flocculation of the filler is a possible strategy to increase the filler content of paper without deterioration of strength properties. A modified laboratory hand sheet former, known as the Rapid Drainage Device (RDD) was used. The major modification consisted of a long pipe that acted as a suction leg, which provides a dewatering vacuum at the same level as on a paper machine. The experimental results showed that mechanical filler retention increased linearly with particle size and grammage of the fibre layer above a critical grammage which depended on particle size. The linear relation was also seen in a pilot scale trial on the FEX pilot-paper machine at Innventia. During this trial fine paper was produced using pre-flocculated filler where the mean particle size of the flocs and fibres was measured in the flow to the headbox. The results from this pilot trial show that mechanical retention is an important part of the total filler retention. Drainage time and therefore drainage resistance increased with the grammage of the fibre layer and amount of quartz particle added. Drainage time, compared at total grammage (i.e. the sum of fibre and quartz particle grammage) was lowest for a fraction of medium-sized particles, with a median size of 35 μm. There was no obvious effect on retention or drainage resistance of a change in the dewatering pressure from 27.5 to 41.5 kPa.
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| 4. |
- Athley, Karin, et al.
(författare)
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Optimizing the benefit of retention chemicals
- 2014
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Konferensbidrag (refereegranskat)abstract
- Pre-flocculation of filler has been tested as a concept for improving the retention of filler and the strength properties of the sheet. The impact of the size of the filler floes on the mechanical retentionin a fibre network was investigated using a modified laboratory hand sheet former. The mechanical retention was found to increase linearly with both particle size and grammage of the fibre web. These results were confirmed in a full scale production trial on the FEX pilot paper machine at Innventia. Here different filler floe sizes were created through different chemical pre-flocculation strategies. The particle size in the flow to the headbox was measured with FBRM, and a linear relation between particle size and filler retention was found. Corresponding linear relation was seen in a pilot trial when adding filler and retention aid conventionally. This implies that mechanical retention constitute an important part of the filler retention not only upon pre-flocculation but also with conventional addition of filler and retention aid. Thus, the particle size before the headbox can be a good indicator of the retention level. For the conventional application of a two component retention aid system, the increased filler retention correlated to impaired formation and decreased sheet strength. On the contrary, pre-flocculation led to an increase in both sheet strength and filler retention, demonstrating the advantage of pre-flocculating filler.
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| 5. |
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| 6. |
- Benedict, Christian, et al.
(författare)
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Fat Mass and Obesity-Associated Gene (FTO) Is Linked to Higher Plasma Levels of the Hunger Hormone Ghrelin and Lower Serum Levels of the Satiety Hormone Leptin in Older Adults
- 2014
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 63:11, s. 3955-3959
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Tidskriftsartikel (refereegranskat)abstract
- The mechanisms through which common polymorphisms in the fat mass and obesity-associated gene (FTO) drive the development of obesity in humans are poorly understood. Using cross-sectional data from 985 older people (50% females) who participated at age 70 years in the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS), circulating levels of ghrelin and leptin were measured after an overnight fast. In addition, subjects were genotyped for FTO rs17817449 (AA, n = 345 [35%]; AC/CA, n = 481 [48.8%]; CC, n = 159 [16.1%]). Linear regression analyses controlling for sex, selfreported physical activity level, fasting plasma glucose, and BMI were used. A positive relationship between the number of FTO C risk alleles and plasma ghrelin levels was found (P = 0.005; relative plasma ghrelin difference between CC and AA carriers = similar to 9%). In contrast, serum levels of the satiety-enhancing hormone leptin were inversely linked to the number of FTO C risk alleles (P = 0.001; relative serum leptin difference between CC and AA carriers = similar to 11%). These associations were also found when controlling for waist circumference. The present findings suggest that FTO may facilitate weight gain in humans by shifting the endocrine balance from the satiety hormone leptin toward the hunger-promoting hormone ghrelin.
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| 7. |
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| 8. |
- Callieri, Marco, et al.
(författare)
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Documentation and Interpretation of an Archeological Excavation: an experience with Dense Stereo Reconstruction tools
- 2011
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Ingår i: [Host publication title missing]. - 1811-864X. - 9783905674347 ; , s. 33-40
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Konferensbidrag (refereegranskat)abstract
- An archeological excavation is usually a rapidly evolving environment: several factors (weather, costs, permissions) force the work to be concentrated in a few weeks. Moreover, excavating is essentially a mono-directional operation, which constantly modifies the state of the site. Since most of the interpretation is performed in a second stage, it is necessary to collect a massive amount of documentation (images, sketches, notes, measurements). In this paper we present an experiment of monitoring of an excavation in Uppåkra, South Sweden, using dense stereo matching techniques. The archeologists were trained to collect a set of images every day; the set was used to produce a 3D model depicting the state of the excavation. In this way, it was possible to obtain a reliable geometric representation of the evolution of the excavation. The obtained model were also used by the archeologists, by the means of an open-source tool, to perform a site study and interpretation stage directly on the geometric data. The results of the experimentation show that dense stereo matching can be easily integrated with the daily work of archeologists in the context of an excavation, and it can provide a valuable source of data for interpretation, archival and integration of acquired material.
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| 9. |
- Carlson, Johan, 1972, et al.
(författare)
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Non-nominal path planning for robust robotic assembly
- 2013
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Ingår i: Journal of Manufacturing Systems. - : Elsevier BV. - 0278-6125. ; 32:3, s. 429-435
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Tidskriftsartikel (refereegranskat)abstract
- In manufacturing and assembly processes it is important, in terms of time and money, to verify the feasi-bility of the operations at the design stage and at early production planning. To achieve that, verificationin a virtual environment is often performed by using methods such as path planning and simulation ofdimensional variation. Lately, these areas have gained interest both in industry and academia, however,they are almost always treated as separate activities, leading to unnecessary tight tolerances and on-lineadjustments.To resolve this, we present a novel procedure based on the interaction between path planning tech-niques and variation simulation. This combined tool is able to compute robust assembly paths forindustrial robots, i.e. paths less sensitive to the geometrical variation existing in the robot links, in itscontrol system, and in the environment. This may lead to increased productivity and may limit errorsources. The main idea to improve robustness is to enable robots to avoid motions in areas with highvariation, preferring instead low variation zones. The method is able to deal with the different geometricalvariation due to the different robot kinematic configurations. Computing variation might be a computa-tionally expensive task or variation data might be unavailable in the entire state space, therefore threedifferent ways to estimate variation are also proposed and compared. An industrial test case from theautomotive industry is successfully studied and the results are presented.
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| 10. |
- Dahl, Markus, et al.
(författare)
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Fine-Tuning of Smad Protein Function by Poly(ADP-Ribose) Polymerases and Poly(ADP-Ribose) Glycohydrolase during Transforming Growth Factor β Signaling
- 2014
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:8, s. e103651-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Initiation, amplitude, duration and termination of transforming growth factor β (TGFβ) signaling via Smad proteins is regulated by post-translational modifications, including phosphorylation, ubiquitination and acetylation. We previously reported that ADP-ribosylation of Smads by poly(ADP-ribose) polymerase 1 (PARP-1) negatively influences Smad-mediated transcription. PARP-1 is known to functionally interact with PARP-2 in the nucleus and the enzyme poly(ADP-ribose) glycohydrolase (PARG) can remove poly(ADP-ribose) chains from target proteins. Here we aimed at analyzing possible cooperation between PARP-1, PARP-2 and PARG in regulation of TGFβ signaling.METHODS:A robust cell model of TGFβ signaling, i.e. human HaCaT keratinocytes, was used. Endogenous Smad3 ADP-ribosylation and protein complexes between Smads and PARPs were studied using proximity ligation assays and co-immunoprecipitation assays, which were complemented by in vitro ADP-ribosylation assays using recombinant proteins. Real-time RT-PCR analysis of mRNA levels and promoter-reporter assays provided quantitative analysis of gene expression in response to TGFβ stimulation and after genetic perturbations of PARP-1/-2 and PARG based on RNA interference.RESULTS:TGFβ signaling rapidly induces nuclear ADP-ribosylation of Smad3 that coincides with a relative enhancement of nuclear complexes of Smads with PARP-1 and PARP-2. Inversely, PARG interacts with Smads and can de-ADP-ribosylate Smad3 in vitro. PARP-1 and PARP-2 also form complexes with each other, and Smads interact and activate auto-ADP-ribosylation of both PARP-1 and PARP-2. PARP-2, similar to PARP-1, negatively regulates specific TGFβ target genes (fibronectin, Smad7) and Smad transcriptional responses, and PARG positively regulates these genes. Accordingly, inhibition of TGFβ-mediated transcription caused by silencing endogenous PARG expression could be relieved after simultaneous depletion of PARP-1.CONCLUSION:Nuclear Smad function is negatively regulated by PARP-1 that is assisted by PARP-2 and positively regulated by PARG during the course of TGFβ signaling.
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