| 1. |
- Tabiri, S, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 2. |
- Bravo, L, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 3. |
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| 4. |
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| 5. |
- Zaborowski, AM, et al.
(författare)
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Microsatellite instability in young patients with rectal cancer: molecular findings and treatment response
- 2022
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Ingår i: The British journal of surgery. - : Oxford University Press (OUP). - 1365-2168 .- 0007-1323. ; 109:3, s. 251-255
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Tidskriftsartikel (refereegranskat)abstract
- In this study of 400 patients with early-onset rectal cancer, 12.5 per cent demonstrated microsatellite instability (MSI). MSI was associated with a reduced likelihood of nodal positivity, an increased rate of pathological complete response, and improved disease-specific survival.
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| 6. |
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| 7. |
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| 8. |
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| 9. |
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| 10. |
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| 11. |
- Haghikia, A., et al.
(författare)
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Propionate attenuates atherosclerosis by immune-dependent regulation of intestinal cholesterol metabolism
- 2022
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Ingår i: European Heart Journal. - : Oxford University Press (OUP). - 0195-668X .- 1522-9645. ; 43:6, s. 518-533
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Tidskriftsartikel (refereegranskat)abstract
- Aims Atherosclerotic cardiovascular disease (ACVD) is a major cause of mortality and morbidity worldwide, and increased low-density lipoproteins (LDLs) play a critical role in development and progression of atherosclerosis. Here, we examined for the first time gut immunomodulatory effects of the microbiota-derived metabolite propionic acid (PA) on intestinal cholesterol metabolism. Methods and results Using both human and animal model studies, we demonstrate that treatment with PA reduces blood total and LDL cholesterol levels. In apolipoprotein E-/- (Apoe(-/-)) mice fed a high-fat diet (HFD), PA reduced intestinal cholesterol absorption and aortic atherosclerotic lesion area. Further, PA increased regulatory T-cell numbers and interleukin (IL)-10 levels in the intestinal microenvironment, which in turn suppressed the expression of Niemann-Pick C1-like 1 (Npc1l1), a major intestinal cholesterol transporter. Blockade of IL-10 receptor signalling attenuated the PA-related reduction in total and LDL cholesterol and augmented atherosclerotic lesion severity in the HFD-fed Apoe(-/-) mice. To translate these preclinical findings to humans, we conducted a randomized, double-blinded, placebo-controlled human study (clinical trial no. NCT03590496). Oral supplementation with 500 mg of PA twice daily over the course of 8 weeks significantly reduced LDL [-15.9 mg/dL (-8.1%) vs. -1.6 mg/dL (-0.5%), P = 0.016], total [-19.6 mg/dL (-7.3%) vs. -5.3 mg/dL (-1.7%), P = 0.014] and non-high-density lipoprotein cholesterol levels [PA vs. placebo: -18.9 mg/dL (-9.1%) vs. -0.6 mg/dL (-0.5%), P = 0.002] in subjects with elevated baseline LDL cholesterol levels. Conclusion Our findings reveal a novel immune-mediated pathway linking the gut microbiota-derived metabolite PA with intestinal Npc1l1 expression and cholesterol homeostasis. The results highlight the gut immune system as a potential therapeutic target to control dyslipidaemia that may introduce a new avenue for prevention of ACVDs.
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| 12. |
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| 13. |
- Teo, Kevin, et al.
(författare)
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rs641738C>T near MBOAT7 is associated with liver fat, ALT, and fibrosis in NAFLD: a meta-analysis.
- 2021
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Ingår i: Journal of hepatology. - : Elsevier BV. - 1600-0641 .- 0168-8278. ; 74:1, s. 20-30
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Tidskriftsartikel (refereegranskat)abstract
- A common genetic variant near MBOAT7 (rs641738C>T) has been previously associated with hepatic fat and advanced histology in non-alcoholic fatty liver disease (NAFLD), however, these findings have not been consistently replicated in the literature. We aimed to establish whether rs641738C>T is a risk factor across the spectrum of NAFLD and characterize its role in the regulation of related metabolic phenotypes through meta-analysis.We performed meta-analysis of studies with data on the association between rs641738C>T genotype and: liver fat, NAFLD histology, and serum ALT, lipids, or insulin. These included directly genotyped studies and population-level data from genome-wide association studies (GWAS). We performed random effects meta-analysis using recessive, additive, and dominant genetic models.Data from 1,066,175 participants (9,688 with liver biopsies) across 42 studies were included in the meta-analysis. rs641738C>T was associated with higher liver fat on CT/MRI (+0.03 standard deviations [95% CI: 0.02 - 0.05], pz=4.8x10-5) and diagnosis of NAFLD (OR 1.17 [95% CI 1.05 - 1.3], pz=0.003) in Caucasian adults. The variant was also positively associated with presence of advanced fibrosis (OR 1.22 [95% CI: 1.03 - 1.45], pz=0.021) in Caucasian adults using a recessive model of inheritance (CC+CT vs. TT). Meta-analysis of data from previous GWAS found the variant to be associated with higher ALT (pz=0.002) and lower serum triglycerides (pz=1.5x10-4). rs641738C>T was not associated with fasting insulin and no effect was observed in children with NAFLD.Our study validates rs641738C>T near MBOAT7 as a risk factor for the presence and severity of NAFLD in individuals of European descent.
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| 14. |
- Wernly, B, et al.
(författare)
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Anti-CD3 Antibody Treatment Reduces Scar Formation in a Rat Model of Myocardial Infarction
- 2020
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Ingår i: Cells. - : MDPI AG. - 2073-4409. ; 9:2
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Antibody treatment with anti-thymocyte globulin (ATG) has been shown to be cardioprotective. We aimed to evaluate which single anti-T-cell epitope antibody alters chemokine expression at a level similar to ATG and identified CD3, which is a T-cell co-receptor mediating T-cell activation. Based on these results, the effects of anti-CD3 antibody treatment on angiogenesis and cardioprotection were tested in vitro and in vivo. Methods: Concentrations of IL-8 and MCP-1 in supernatants of human peripheral blood mononuclear cell (PBMC) cultures following distinct antibody treatments were evaluated by Enzyme-linked Immunosorbent Assay (ELISA). In vivo, anti-CD3 antibodies or vehicle were injected intravenously in rats subjected to acute myocardial infarction (AMI). Chemotaxis and angiogenesis were evaluated using tube and migration assays. Intracellular pathways were assessed using Western blot. Extracellular vesicles (EVs) were quantitatively evaluated using fluorescence-activated cell scanning, exoELISA, and nanoparticle tracking analysis. Also, microRNA profiles were determined by next-generation sequencing. Results: Only PBMC stimulation with anti-CD3 antibody led to IL-8 and MCP-1 changes in secretion, similar to ATG. In a rat model of AMI, systemic treatment with an anti-CD3 antibody markedly reduced infarct scar size (27.8% (Inter-quartile range; IQR 16.2–34.9) vs. 12.6% (IQR 8.3–27.2); p < 0.01). The secretomes of anti-CD3 treated PBMC neither induced cardioprotective pathways in cardiomyocytes nor pro-angiogenic mechanisms in human umbilical vein endothelial cell (HUVECs) in vitro. While EVs quantities remained unchanged, PBMC incubation with an anti-CD3 antibody led to alterations in EVs miRNA expression. Conclusion: Treatment with an anti-CD3 antibody led to decreased scar size in a rat model of AMI. Whereas cardioprotective and pro-angiogenetic pathways were unaltered by anti-CD3 treatment, qualitative changes in the EVs miRNA expression could be observed, which might be causal for the observed cardioprotective phenotype. We provide evidence that EVs are a potential cardioprotective treatment target. Our findings will also provide the basis for a more detailed analysis of putatively relevant miRNA candidates.
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| 15. |
- Lener, Thomas, et al.
(författare)
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Applying extracellular vesicles based therapeutics in clinical trials - an ISEV position paper.
- 2015
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Ingår i: Journal of extracellular vesicles. - : Wiley. - 2001-3078. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Extracellular vesicles (EVs), such as exosomes and microvesicles, are released by different cell types and participate in physiological and pathophysiological processes. EVs mediate intercellular communication as cell-derived extracellular signalling organelles that transmit specific information from their cell of origin to their target cells. As a result of these properties, EVs of defined cell types may serve as novel tools for various therapeutic approaches, including (a) anti-tumour therapy, (b) pathogen vaccination, (c) immune-modulatory and regenerative therapies and (d) drug delivery. The translation of EVs into clinical therapies requires the categorization of EV-based therapeutics in compliance with existing regulatory frameworks. As the classification defines subsequent requirements for manufacturing, quality control and clinical investigation, it is of major importance to define whether EVs are considered the active drug components or primarily serve as drug delivery vehicles. For an effective and particularly safe translation of EV-based therapies into clinical practice, a high level of cooperation between researchers, clinicians and competent authorities is essential. In this position statement, basic and clinical scientists, as members of the International Society for Extracellular Vesicles (ISEV) and of the European Cooperation in Science and Technology (COST) program of the European Union, namely European Network on Microvesicles and Exosomes in Health and Disease (ME-HaD), summarize recent developments and the current knowledge of EV-based therapies. Aspects of safety and regulatory requirements that must be considered for pharmaceutical manufacturing and clinical application are highlighted. Production and quality control processes are discussed. Strategies to promote the therapeutic application of EVs in future clinical studies are addressed.
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| 16. |
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| 17. |
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| 18. |
- Krampert, Monika, et al.
(författare)
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Smad7 Regulates the Adult Neural Stem/Progenitor Cell Pool in a Transforming Growth Factor β- and Bone Morphogenetic Protein-Independent Manner
- 2010
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Ingår i: Molecular and Cellular Biology. - : American Society for Microbiology. - 0270-7306 .- 1098-5549. ; 30:14, s. 3685-3694
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Tidskriftsartikel (refereegranskat)abstract
- Members of the transforming growth factor beta (TGF-beta) family of proteins modulate the proliferation, differentiation, and survival of many different cell types. Neural stem and progenitor cells (NPCs) in the adult brain are inhibited in their proliferation by TGF-beta and by bone morphogenetic proteins (BMPs). Here, we investigated neurogenesis in a hypomorphic mouse model for the TGF-beta and BMP inhibitor Smad7, with the hypothesis that NPC proliferation might be reduced due to increased TGF-beta and BMP signaling. Unexpectedly, we found enhanced NPC proliferation as well as an increased number of label-retaining cells in vivo. The enhanced proliferation potential of mutant cells was retained in vitro in neurosphere cultures. We observed a higher sphere-forming capacity as well as faster growth and cell cycle progression. Use of specific inhibitors revealed that these effects were independent of TGF-beta and BMP signaling. The enhanced proliferation might be at least partially mediated by elevated signaling via epidermal growth factor (EGF) receptor, as mutant cells showed higher expression and activation levels of the EGF receptor. Conversely, an EGF receptor inhibitor reduced the proliferation of these cells. Our data indicate that endogenous Smad7 regulates neural stem/progenitor cell proliferation in a TGF-beta- and BMP-independent manner.
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| 19. |
- Stange, D E, et al.
(författare)
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Expression of an ASCL2 related stem cell signature and IGF2 in colorectal cancer liver metastases with 11p15.5 gain.
- 2010
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Ingår i: Gut. - : BMJ. - 0017-5749 .- 1468-3288. ; 59:9
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND AIMS: Liver metastases are the leading cause of death in colorectal cancer. To gain better insight into the biology of metastasis and possibly identify new therapeutic targets we systematically investigated liver-metastasis-specific molecular aberrations.METHODS: Primary colorectal cancer (pCRC) and matched liver metastases (LMs) from the same patients were analysed by microarray-based comparative genomic hybridisation in 21 pairs and gene expression profiling in 18 pairs. Publicly available databases were used to confirm findings in independent datasets.RESULTS: Chromosome aberration patterns and expression profiles of pCRC and matched LMs were strikingly similar. Unsupervised cluster analysis of genomic data showed that 20/21 pairs were more similar to each other than to any other analysed tumour. A median of only 11 aberrations per patient was found to be different between pCRC and LM, and expression of only 16 genes was overall changed upon metastasis. One region on chromosome band 11p15.5 showed a characteristic gain in LMs in 6/21 patients. This gain could be confirmed in an independent dataset of LMs (n=50). Localised within this region, the growth factor IGF2 (p=0.003) and the intestinal stem cell specific transcription factor ASCL2 (p=0.029) were found to be over-expressed in affected LM. Several ASCL2 target genes were upregulated in this subgroup of LM, including the intestinal stem cell marker OLFM4 (p=0.013). The correlation between ASCL2 expression and four known direct transcriptional targets (LGR5, EPHB3, ETS2 and SOX9) could be confirmed in an independent expression dataset (n=50).CONCLUSIONS: With unprecedented resolution a striking conservation of genomic alterations was demonstrated in liver metastases, suggesting that metastasis typically occurs after the pCRC has fully matured. In addition, we characterised a subset of liver metastases with an ASCL2-related stem-cell signature likely to affect metastatic behaviour of tumour cells.
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| 20. |
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| 21. |
- Xu, H., et al.
(författare)
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Tau Silencing by siRNA in the P301S Mouse Model of Tauopathy
- 2014
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Ingår i: Current Gene Therapy. - : Bentham Science Publishers Ltd.. - 1566-5232. ; 14:5, s. 343-351
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Tidskriftsartikel (refereegranskat)abstract
- Suppression of tau protein expression has been shown to improve behavioral deficits in mouse models of tauopathies, offering an attractive therapeutic approach. Experimentally this had been achieved by switching off the promoters controlling the transgenic human tau gene (MAPT), which is not possible in human patients. The aim of the present study was therefore to evaluate the effectiveness of small interfering RNAs (siRNAs) and their cerebral delivery to suppress human tau expression in vivo, which might be a therapeutic option for human tauopathies. We used primary cortical neurons of transgenic mice expressing P301S-mutated human tau and Lund human mesencephalic (LUHMES) cells to validate the suppressive effect of siRNA in vitro. For measuring the effect in vivo, we stereotactically injected siRNA into the brains of P301S mice to reveal the suppression of tau by immunochemistry (AT180, MC1, and CP13 antibodies). We found that the Accell((TM)) SMART pool siRNA against MAPT can effectively suppress tau expression in vitro and in vivo without a specific delivery agent. The siRNA showed a moderate distribution in the hippocampus of mice after single injection. NeuN, GFAP, Iba-1, MHC II immunoreactivities and the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay showed neither signs of neurotoxicity or neuroinflammation nor apoptosis when MAPT siRNA is present in the hippocampus. Our data suggest that siRNA against MAPT can serve as a potential tool for gene therapy in tauopathies.
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| 22. |
- Ambros, Inge M, et al.
(författare)
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A multilocus technique for risk evaluation of patients with neuroblastoma.
- 2011
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Ingår i: Clinical cancer research : an official journal of the American Association for Cancer Research. - 1078-0432. ; 17:4, s. 792-804
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Tidskriftsartikel (refereegranskat)abstract
- Precise and comprehensive analysis of neuroblastoma genetics is essential for accurate risk evaluation and only pangenomic/multilocus approaches fulfill the present-day requirements. We present the establishment and validation of the PCR-based multiplex ligation-dependent probe amplification (MLPA) technique for neuroblastoma.
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| 23. |
- De La Fuente, Alerie Guzman, et al.
(författare)
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Pericytes Stimulate Oligodendrocyte Progenitor Cell Differentiation during CNS Remyelination
- 2017
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Ingår i: Cell Reports. - : Elsevier BV. - 2211-1247. ; 20:8, s. 1755-1764
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Tidskriftsartikel (refereegranskat)abstract
- The role of the neurovascular niche in CNS myelin regeneration is incompletely understood. Here, we show that, upon demyelination, CNS-resident pericytes (PCs) proliferate, and parenchymal non-vessel-associated PC-like cells (PLCs) rapidly develop. During remyelination, mature oligodendrocytes were found in close proximity to PCs. In Pdgfb(ret/ret) mice, which have reduced PC numbers, oligodendrocyte progenitor cell (OPC) differentiation was delayed, although remyelination proceeded to completion. PC-conditioned medium accelerated and enhanced OPC differentiation in vitro and increased the rate of remyelination in an ex vivo cerebellar slice model of demyelination. We identified Lama2 as a PC-derived factor that promotes OPC differentiation. Thus, the functional role of PCs is not restricted to vascular homeostasis but includes the modulation of adult CNS progenitor cells involved in regeneration.
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| 24. |
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| 25. |
- Kempermann, G., et al.
(författare)
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Human Adult Neurogenesis: Evidence and Remaining Questions
- 2018
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Ingår i: Cell Stem Cell. - : Elsevier BV. - 1934-5909 .- 1875-9777. ; 23:1, s. 25-30
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Tidskriftsartikel (refereegranskat)abstract
- Renewed discussion about whether or not adult neurogenesis exists in the human hippocampus, and the nature and strength of the supporting evidence, has been reignited by two prominently published reports with opposite conclusions. Here, we summarize the state of the field and argue that there is currently no reason to abandon the idea that adult-generated neurons make important functional contributions to neural plasticity and cognition across the human lifespan.
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| 26. |
- Koblmuller, Stephan, et al.
(författare)
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Phylogeographic structure and gene flow in the scale-eating cichlid Perissodus microlepis (Teleostei, Perciformes, Cichlidae) in southern Lake Tanganyika
- 2009
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Ingår i: Zoologica Scripta. - : Wiley. - 0300-3256 .- 1463-6409. ; 38:3, s. 257-268
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Tidskriftsartikel (refereegranskat)abstract
- One of the most fragmented habitats in freshwater lakes is the rocky littoral zone, where the already richly structured habitat is frequently interspersed with more pronounced barriers such as sandy bays, river estuaries and deep slopes. Although habitat fragmentation generally constrains the dispersal of specialized rock-dwelling species, patterns of population structure vary in sympatric taxa due to species-specific traits. In the present study, we examine the phylogeographic and population genetic structure of Perissodus microlepis, a presumptively highly mobile scale-eating cichlid fish endemic to Lake Tanganyika with a lake-wide distribution in the rocky littoral zone and no obvious geographical colour variation. Analysis of the mitochondrial DNA of six populations in the southern end of the lake suggests isolation by distance along rocky shoreline. Across a large muddy bay, a phylogeographic break indicates that environmental barriers restrict gene flow even in this highly mobile species. Restricted dispersal across the bay is not necessarily a consequence of an intrinsic propensity to avoid sand, but may be connected with the association between P. microlepis and other rock-dwelling fish, which the scale-eaters mimic and intermingle in order to be able to approach other fish to rip off scales from their bodies.
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| 27. |
- Kruger, P., et al.
(författare)
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Ultracold atoms on atom chips : Manipulation at the mu m distance scale
- 2005
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Ingår i: ATOMIC PHYSICS 19. - : AIP. ; , s. 144-153
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Konferensbidrag (refereegranskat)abstract
- Miniaturized potentials near the surface of atom chips can be used as flexible and versatile tools for the manipulation of ultracold atoms on a microscale. The full scope of possibilities is only accessible if atom‐surface distances can be reduced to microns. We discuss experiments in this regime and potential obstacles and solutions. We show that appropriate fabrication techniques lead to a reduction of disorder potentials so that one‐dimensional condensates can be prepared. We demonstrate how electrostatic potentials can be used to modify magnetic trapping potentials and how they can be used to study condensate formation in situations of different dimensionality. © 2005 American Institute of Physics
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| 28. |
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| 29. |
- Megyesfalvi, Zsolt, et al.
(författare)
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Unfolding the secrets of small cell lung cancer progression : Novel approaches and insights through rapid autopsies
- 2023
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Ingår i: Cancer Cell. - 1535-6108. ; 41:9, s. 1535-1540
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Tidskriftsartikel (refereegranskat)abstract
- The understanding of small cell lung cancer (SCLC) biology has increased dramatically in recent years, but the processes that allow SCLC to progress rapidly remain poorly understood. Here, we advocate the integration of rapid autopsies and preclinical models into SCLC research as a comprehensive strategy with the potential to revolutionize current treatment paradigms.
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| 30. |
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| 31. |
- Mörwald, Katharina, et al.
(författare)
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Serum Ferritin Correlates With Liver Fat in Male Adolescents With Obesity.
- 2020
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Ingår i: Frontiers in Endocrinology. - : Frontiers Media SA. - 1664-2392. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Non-alcoholic fatty liver disease (NAFLD) contributes essentially to the burden of obesity and can start in childhood. NAFLD can progress to cirrhosis and hepatocellular carcinoma. The early phase of NAFLD is crucial because during this time the disease is fully reversible. Pediatric NAFLD shows unique features of histology and pathophysiology compared to adults. Changes in serum iron parameters are common in adult NAFLD and have been termed dysmetabolic iron overload syndrome characterized by increased serum ferritin levels and normal transferrin saturation; however, the associations of serum ferritin, inflammation, and liver fat content have been incompletely investigated in children. As magnetic resonance imaging (MRI) is an excellent measure for the degree of liver steatosis, we applied this method herein to clarify the interaction between ferritin and fatty liver in male adolescents. For this study, one hundred fifty male pediatric patients with obesity and who are overweight were included. We studied a subgroup of male patients with (n = 44) and without (n = 18) NAFLD in whom we determined liver fat content, visceral adipose tissue, and subcutaneous adipose tissue extent with a 1.5T MRI (Philips NL). All patients underwent a standardized oral glucose tolerance test. We measured uric acid, triglycerides, HDL-, LDL-, total cholesterol, liver transaminases, high sensitive CRP (hsCRP), interleukin-6, HbA1c, and insulin. In univariate analysis, ferritin was associated with MRI liver fat, visceral adipose tissue content, hsCRP, AST, ALT, and GGT, while transferrin and soluble transferrin receptor were not associated with ferritin. Multivariate analysis identified hsCRP and liver fat content as independent predictors of serum ferritin in the pediatric male patients. Our data indicate that serum ferritin in male adolescents with obesity is mainly determined by liver fat content and inflammation but not by body iron status.
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| 32. |
- Schänzer, Anne, et al.
(författare)
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Direct stimulation of adult neural stem cells in vitro and neurogenesis in vivo by vascular endothelial growth factor.
- 2004
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Ingår i: Brain pathology (Zurich, Switzerland). - 1015-6305. ; 14:3, s. 237-48
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Tidskriftsartikel (refereegranskat)abstract
- Hypoxia as well as global and focal ischemia are strong activators of neurogenesis in the adult mammalian central nervous system. Here we show that the hypoxia-inducible vascular endothelial growth factor (VEGF) and its receptor VEGFR-2/Flk-1 are expressed in clonally-derived adult rat neural stem cells in vitro. VEGF stimulated the expansion of neural stem cells whereas blockade of VEGFR-2/Flk-1-kinase activity reduced neural stem cell expansion. VEGF was also infused into the lateral ventricle to study changes in neurogenesis in the ventricle wall, olfactory bulb and hippocampus. Using a low dose (2.4 ng/d) to avoid endothelial proliferation and changes in vascular permeability, VEGF stimulated adult neurogenesis in vivo. After VEGF infusion, we observed reduced apoptosis but unaltered proliferation suggesting a survival promoting effect of VEGF in neural progenitor cells. Strong expression of VEGFR-2/Flk-1 was detected in the ventricle wall adjacent to the choroid plexus, a site of significant VEGF production, which suggests a paracrine function of endogenous VEGF on neural stem cells in vivo. We propose that VEGF acts as a trophic factor for neural stem cells in vitro and for sustained neurogenesis in the adult nervous system.These findings may have implications for the pathogenesis and therapy of neurodegenerative diseases.
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| 33. |
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| 34. |
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| 35. |
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| 36. |
- Wagner, Raik, et al.
(författare)
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Deletion of FtsH11 protease has impact on chloroplast structure and function in Arabidopsis thaliana when grown under continuous light
- 2016
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Ingår i: Plant Cell and Environment. - : Wiley. - 0140-7791 .- 1365-3040. ; 39:11, s. 2530-2544
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Tidskriftsartikel (refereegranskat)abstract
- The membrane-integrated metalloprotease FtsH11 of Arabidopsis thaliana is proposed to be dual-targeted to mitochondria and chloroplasts. A bleached phenotype was observed in ftsh11 grown at long days or continuous light, pointing to disturbances in the chloroplast. Within the chloroplast, FtsH11 was found to be located exclusively in the envelope. Two chloroplast-located proteins of unknown function (Tic22-like protein and YGGT-A) showed significantly higher abundance in envelope membranes and intact chloroplasts of ftsh11 and therefore qualify as potential substrates for the FtsH11 protease. No proteomic changes were observed in the mitochondria of 6-week-old ftsh11 compared with wild type, and FtsH11 was not immunodetected in these organelles. The abundance of plastidic proteins, especially of photosynthetic proteins, was altered even during standard growth conditions in total leaves of ftsh11. At continuous light, the amount of photosystem I decreased relative to photosystem II, accompanied by a drastic change of the chloroplast morphology and a drop of non-photochemical quenching. FtsH11 is crucial for chloroplast structure and function during growth in prolonged photoperiod. The membrane-integrated metalloprotease FtsH11 of Arabidopsis thaliana was found to be located exclusively in the chloroplast envelope and to be crucial for chloroplast structure and function during growth in prolonged photoperiod. Two chloroplast-located proteins of unknown function (Tic22-like protein and YGGT-A) showed significantly higher abundance in envelope membranes and intact chloroplasts of ftsH11 and therefore qualify as potential substrates for the FtsH11 protease.
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