| 1. |
- Niemi, MEK, et al.
(author)
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- 2021
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swepub:Mat__t
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| 2. |
- Kanai, M, et al.
(author)
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- 2023
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swepub:Mat__t
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| 3. |
- Andresen, G. B., et al.
(author)
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Evaporative Cooling of Antiprotons to Cryogenic Temperatures
- 2010
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In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 105:1, s. 013003-
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Journal article (peer-reviewed)abstract
- We report the application of evaporative cooling to clouds of trapped antiprotons, resulting in plasmas with measured temperature as low as 9 K. We have modeled the evaporation process for charged particles using appropriate rate equations. Good agreement between experiment and theory is observed, permitting prediction of cooling efficiency in future experiments. The technique opens up new possibilities for cooling of trapped ions and is of particular interest in antiproton physics, where a precise CPT test on trapped antihydrogen is a long-standing goal.
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| 4. |
- Andresen, G. B., et al.
(author)
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Search for trapped antihydrogen
- 2011
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In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 695:1-4, s. 95-104
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Journal article (peer-reviewed)abstract
- We present the results of an experiment to search for trapped antihydrogen atoms with the ALPHA antihydrogen trap at the CERN Antiproton Decelerator. Sensitive diagnostics of the temperatures, sizes, and densities of the trapped antiproton and positron plasmas have been developed, which in turn permitted development of techniques to precisely and reproducibly control the initial experimental parameters. The use of a position-sensitive annihilation vertex detector, together with the capability of controllably quenching the superconducting magnetic minimum trap, enabled us to carry out a high-sensitivity and low-background search for trapped synthesised antihydrogen atoms. We aim to identify the annihilations of antihydrogen atoms held for at least 130 ms in the trap before being released over ~30 ms. After a three-week experimental run in 2009 involving mixing of 107 antiprotons with 1.3ￜ109 positrons to produce 6ￜ105 antihydrogen atoms, we have identified six antiproton annihilation events that are consistent with the release of trapped antihydrogen. The cosmic ray background, estimated to contribute 0.14 counts, is incompatible with this observation at a significance of 5.6 sigma. Extensive simulations predict that an alternative source of annihilations, the escape of mirror-trapped antiprotons, is highly unlikely, though this possibility has not yet been ruled out experimentally.
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| 5. |
- Charlton, M, et al.
(author)
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Antiparticle sources for antihydrogen production and trapping
- 2011
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In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596. ; 262, s. 012001-
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Journal article (peer-reviewed)abstract
- Sources of positrons and antiprotons that are currently used for the formation of antihydrogen with low kinetic energies are reviewed, mostly in the context of the ALPHA collaboration and its predecessor ATHENA. The experiments were undertaken at the Antiproton Decelerator facility, which is located at CERN. Operations performed on the clouds of antiparticles to facilitate their mixing to produce antihydrogen are described. These include accumulation, cooling and manipulation. The formation of antihydrogen and some of the characteristics of the anti-atoms that are created are discussed. Prospects for trapping antihydrogen in a magnetic minimum trap, as envisaged by the ALPHA collaboration, are reviewed.
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| 6. |
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| 7. |
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| 8. |
- Tomić, I., et al.
(author)
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Shake-table testing of a stone masonry building aggregate : overview of blind prediction study
- 2023
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In: Bulletin of Earthquake Engineering. - : Springer Science and Business Media LLC. - 1570-761X .- 1573-1456.
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Journal article (peer-reviewed)abstract
- City centres of Europe are often composed of unreinforced masonry structural aggregates, whose seismic response is challenging to predict. To advance the state of the art on the seismic response of these aggregates, the Adjacent Interacting Masonry Structures (AIMS) subproject from Horizon 2020 project Seismology and Earthquake Engineering Research Infrastructure Alliance for Europe (SERA) provides shake-table test data of a two-unit, double-leaf stone masonry aggregate subjected to two horizontal components of dynamic excitation. A blind prediction was organized with participants from academia and industry to test modelling approaches and assumptions and to learn about the extent of uncertainty in modelling for such masonry aggregates. The participants were provided with the full set of material and geometrical data, construction details and original seismic input and asked to predict prior to the test the expected seismic response in terms of damage mechanisms, base-shear forces, and roof displacements. The modelling approaches used differ significantly in the level of detail and the modelling assumptions. This paper provides an overview of the adopted modelling approaches and their subsequent predictions. It further discusses the range of assumptions made when modelling masonry walls, floors and connections, and aims at discovering how the common solutions regarding modelling masonry in general, and masonry aggregates in particular, affect the results. The results are evaluated both in terms of damage mechanisms, base shear forces, displacements and interface openings in both directions, and then compared with the experimental results. The modelling approaches featuring Discrete Element Method (DEM) led to the best predictions in terms of displacements, while a submission using rigid block limit analysis led to the best prediction in terms of damage mechanisms. Large coefficients of variation of predicted displacements and general underestimation of displacements in comparison with experimental results, except for DEM models, highlight the need for further consensus building on suitable modelling assumptions for such masonry aggregates.
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| 9. |
- Butler, E., et al.
(author)
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Towards antihydrogen trapping and spectroscopy at ALPHA
- 2011
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In: Hyperfine Interactions. - : Springer Science and Business Media LLC. - 0304-3843 .- 1572-9540. ; 199:1, s. 39-48
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Journal article (peer-reviewed)abstract
- Spectroscopy of antihydrogen has the potential to yield high-precision tests of the CPT theorem and shed light on the matter-antimatter imbalance in the Universe. The ALPHA antihydrogen trap at CERN’s Antiproton Decelerator aims to prepare a sample of antihydrogen atoms confined in an octupole-based Ioffe trap and to measure the frequency of several atomic transitions. We describe our techniques to directly measure the antiproton temperature and a new technique to cool them to below 10 K. We also show how our unique position-sensitive annihilation detector provides us with a highly sensitive method of identifying antiproton annihilations and effectively rejecting the cosmic-ray background.
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| 10. |
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| 11. |
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| 12. |
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| 13. |
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| 14. |
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| 15. |
- Frías, Juan P., et al.
(author)
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Long-term effects of dapagliflozin plus saxagliptin versus glimepiride on a background of metformin in patients with type 2 diabetes: Results of a 104-week extension to a 52-week randomized, phase 3 study and liver fat MRI substudy
- 2022
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In: Diabetes, Obesity and Metabolism. - : Wiley. - 1463-1326 .- 1462-8902. ; 24:1, s. 61-71
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Journal article (peer-reviewed)abstract
- Aim: To report the results of a 104-week extension to a 52-week study in which dapagliflozin plus saxagliptin (DAPA+SAXA) improved glycaemic control, liver fat and metabolic variables compared with glimepiride (GLIM) in participants with type 2 diabetes (T2D) receiving background metformin. Materials and methods: This extension to a 52-week global, multicentre, parallel-group, active-controlled, double-blind study (NCT02419612) continued randomized participants (1:1) on DAPA+SAXA (10/5 mg) plus placebo, or GLIM (1-6 mg) plus placebo, once daily. Eligible participants were aged ≥18 years, had T2D (glycated haemoglobin [HbA1c] 58.5-91.3 mmol/mol [7.5%-10.5%]), and a body mass index of 20.0 to 45.0 kg/m2, and were receiving metformin (MET; ≥1500 mg/d). Key outcomes were: requirement for treatment intensification, based on HbA1c ≥53 mmol/mol (7%); achieving therapeutic glycaemic response; and changes in adipose tissue and liver fat on magnetic resonance imaging in a substudy. Results: Overall, 382 participants entered and 338 completed the 104-week extension period (MRI substudy, n = 82). The need for treatment intensification during the 156-week period was lower for DAPA+SAXA+MET (37.0%) than GLIM+MET (55.6%; hazard ratio 0.52, 95% confidence interval [CI] 0.39-0.68; P < 0.001). At week 156, 21.4% of DAPA+SAXA+MET versus 11.7% of GLIM+MET participants achieved therapeutic glycaemic response (HbA1c <53 mmol/mol; odds ratio 2.1, 95% CI 1.23-3.42; P = 0.006). DAPA+SAXA+MET led to greater adjusted mean reductions from baseline in liver fat and visceral and subcutaneous adipose tissue volumes versus GLIM+MET at week 122 (least-squares mean difference from GLIM+MET −4.89%, −0.41 L and −0.44 L, respectively; nominal P values ≤ 0.008). Safety was consistent with that of the monocomponents. Conclusions: Overall, glycaemic control, metabolic benefits and efficacy were better maintained with DAPA+SAXA+MET than with GLIM+MET in T2D.
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| 16. |
- Furtado, R. H. M., et al.
(author)
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Efficacy and Safety of Dapagliflozin in Type 2 Diabetes According to Baseline Blood Pressure: Observations From DECLARE-TIMI 58 Trial
- 2022
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In: Circulation. - : Ovid Technologies (Wolters Kluwer Health). - 0009-7322 .- 1524-4539. ; 145:21, s. 1581-1591
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Journal article (peer-reviewed)abstract
- BACKGROUND: Dapagliflozin improved heart failure and kidney outcomes in patients with type 2 diabetes (T2DM) with or at high risk for atherosclerotic cardiovascular disease in the DECLARE-TIMI 58 trial (Dapagliflozin Effect on Cardiovascular Events - Thrombolysis in Myocardial Infarction 58). Here, the aim was to analyze the efficacy and safety of dapagliflozin stratified according to baseline systolic blood pressure (SBP). METHODS: The DECLARE-TIMI 58 trial randomly assigned patients with T2DM and either previous atherosclerotic cardiovascular disease or atherosclerotic cardiovascular disease risk factors to dapagliflozin or placebo. Patients were categorized by baseline SBP levels: <120, 120 to 129, 130 to 139, 140 to 159, and >= 160 mm Hg (normal, elevated, stage 1, stage 2, and severe hypertension, respectively). Efficacy outcomes of interest were hospitalization for heart failure and a renal-specific composite outcome (sustained decrease in estimated glomerular filtration rate by 40%, progression to end-stage renal disease, or renal death). Safety outcomes included symptoms of volume depletion, lower extremity amputations, and acute kidney injury. RESULTS: The trial comprised 17160 patients; mean age, 64.0 +/- 6.8 years; 37.4% women; median duration of T2DM, 11 years; 40.6% with prevalent cardiovascular disease. Overall, dapagliflozin reduced SBP by 2.4 mm Hg (95% CI, 1.9-2.9; F<0.0001) compared with placebo at 48 months. The beneficial effects of dapagliflozin on hospitalization for heart failure and renal outcomes were consistent across all baseline SBP categories, with no evidence of modification of treatment effect (P-interactions = 5 0.28 and 0.52, respectively). Among normotensive patients, the hazard ratios were 0.66 (95% CI, 0.42-1.05) and 0.39 95% CI, 0.19-0.78), respectively, for hospitalization for heart failure and the renal-specific outcome. Events of volume depletion, amputation, and acute kidney injury did not differ with dapagliflozin overall or within any baseline SBP group. CONCLUSIONS: In patients with T2DM with or at high atherosclerotic cardiovascular disease risk, dapagliflozin reduced risk for hospitalization for heart failure and renal outcomes regardless of baseline SBP, with no difference in adverse events of interest at any level of baseline SBP. These results indicate that dapagliflozin provides cardiorenal benefits in patients with T2DM at high atherosclerotic cardiovascular disease risk independent of baseline blood pressure.
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| 17. |
- Kos, K., et al.
(author)
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In humans the adiponectin receptor R2 is expressed predominantly in adipose tissue and linked to the adipose tissue expression of MMIF-1
- 2010
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In: DIABETES OBESITY AND METABOLISM. - 1462-8902. ; 12:4, s. 360-363
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Journal article (peer-reviewed)abstract
- In this study, the regional adipose tissue-adiponectin (AT-ADN) and adiponectin receptor (R1 and R2) expression and their relation with metabolic parameters, circulating and AT-derived cytokine expressions were compared. Paired subcutaneous adipose tissue (SCAT) and visceral adipose tissue (VAT) were taken from 18 lean and 39 obese humans, AT-mRNA expression of adipokines analysed by RT-PCR and corresponding serum levels by enzyme-linked immunosorbent assay (ELISA). R1 and R2 adipocyte expression was compared with 17 other human tissues. ADN-gene expression was lower in VAT than SCAT [mean (SD) 1.54 (1.1) vs. 2.84 (0.87); p < 0.001], and lower in obese subjects (VAT : p = 0.01;SCAT : p < 0.001). SCAT-ADN correlated positively with serum ADN (r = 0.33;p = 0.036) but not VAT-ADN. AT expressions of ADN and macrophage migration inhibiting factor (MMIF), IL18 and cluster of differentiation factor 14 (CD14) in both depots showed inverse correlations. R1 and R2 were expressed ubiquitously and R2 highest in SCAT, and this is much higher (×100) than R1 (×100). R expression was similar in lean and obese subjects and unrelated to the metabolic syndrome, however, receptors correlated with VAT-MMIF (R 1: r = 0.4;p = 0.008;R 2: r = 0.35,p = 0.02) and SCAT-MMIF expression (R 2: r = 0.43;p = 0.004). Unlike ADN, its receptors are expressed in many human tissues. Human R2 expression is not highest in the liver but in AT where it is associated with MMIF expression. The adiponectin-dependent insulin-sensitizing action of thiazolidinediones is thus probably to differ amongst species with weaker effects on the human liver.
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| 18. |
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| 19. |
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| 20. |
- Schnell, O, et al.
(author)
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CVOT Summit 2022 Report: new cardiovascular, kidney, and glycemic outcomes
- 2023
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In: Cardiovascular diabetology. - : Springer Science and Business Media LLC. - 1475-2840. ; 22:1, s. 59-
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Journal article (other academic/artistic)abstract
- The 8th Cardiovascular Outcome Trial (CVOT) Summit on Cardiovascular, Kidney, and Glycemic Outcomes was held virtually on November 10–12, 2022. Following the tradition of previous summits, this reference congress served as a platform for in-depth discussion and exchange on recently completed outcomes trials as well as key trials important to the cardiovascular (CV) field. This year’s focus was on the results of the DELIVER, EMPA-KIDNEY and SURMOUNT-1 trials and their implications for the treatment of heart failure (HF) and chronic kidney disease (CKD) with sodium-glucose cotransporter-2 (SGLT2) inhibitors and obesity with glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonists. A broad audience of primary care physicians, diabetologists, endocrinologists, cardiologists, and nephrologists participated online in discussions on new consensus recommendations and guideline updates on type 2 diabetes (T2D) and CKD management, overcoming clinical inertia, glycemic markers, continuous glucose monitoring (CGM), novel insulin preparations, combination therapy, and reclassification of T2D. The impact of cardiovascular outcomes on the design of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) trials, as well as the impact of real-world evidence (RWE) studies on the confirmation of CVOT outcomes and clinical trial design, were also intensively discussed. The 9th Cardiovascular Outcome Trial Summit will be held virtually on November 23–24, 2023 (http://www.cvot.org).
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| 21. |
- Skyler, Jay S, et al.
(author)
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Differentiation of diabetes by pathophysiology, natural history, and prognosis
- 2017
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In: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 66:2, s. 241-255
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Research review (peer-reviewed)abstract
- The American Diabetes Association, JDRF, the European Association for the Study of Diabetes, and the American Association of Clinical Endocrinologists convened a research symposium, "The Differentiation of Diabetes by Pathophysiology, Natural History and Prognosis" on 10-12 October 2015. International experts in genetics, immunology, metabolism, endocrinology, and systems biology discussed genetic and environmental determinants of type 1 and type 2 diabetes risk and progression, as well as complications. The participants debated how to determine appropriate therapeutic approaches based on disease pathophysiology and stage and defined remaining research gaps hindering a personalized medical approach for diabetes to drive the field to address these gaps. The authors recommend a structure for data stratification to define the phenotypes and genotypes of subtypes of diabetes that will facilitate individualized treatment.
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| 22. |
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| 23. |
- Wiviott, Stephen D, et al.
(author)
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Dapagliflozin and Cardiovascular Outcomes in Type 2 Diabetes.
- 2019
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In: The New England journal of medicine. - 1533-4406. ; 380:4, s. 347-357
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Journal article (peer-reviewed)abstract
- The cardiovascular safety profile of dapagliflozin, a selective inhibitor of sodium-glucose cotransporter 2 that promotes glucosuria in patients with type 2 diabetes, is undefined.We randomly assigned patients with type 2 diabetes who had or were at risk for atherosclerotic cardiovascular disease to receive either dapagliflozin or placebo. The primary safety outcome was a composite of major adverse cardiovascular events (MACE), defined as cardiovascular death, myocardial infarction, or ischemic stroke. The primary efficacy outcomes were MACE and a composite of cardiovascular death or hospitalization for heart failure. Secondary efficacy outcomes were a renal composite (≥40% decrease in estimated glomerular filtration rate to <60 ml per minute per 1.73 m2 of body-surface area, new end-stage renal disease, or death from renal or cardiovascular causes) and death from any cause.We evaluated 17,160 patients, including 10,186 without atherosclerotic cardiovascular disease, who were followed for a median of 4.2 years. In the primary safety outcome analysis, dapagliflozin met the prespecified criterion for noninferiority to placebo with respect to MACE (upper boundary of the 95% confidence interval [CI], <1.3; P<0.001 for noninferiority). In the two primary efficacy analyses, dapagliflozin did not result in a lower rate of MACE (8.8% in the dapagliflozin group and 9.4% in the placebo group; hazard ratio, 0.93; 95% CI, 0.84 to 1.03; P=0.17) but did result in a lower rate of cardiovascular death or hospitalization for heart failure (4.9% vs. 5.8%; hazard ratio, 0.83; 95% CI, 0.73 to 0.95; P=0.005), which reflected a lower rate of hospitalization for heart failure (hazard ratio, 0.73; 95% CI, 0.61 to 0.88); there was no between-group difference in cardiovascular death (hazard ratio, 0.98; 95% CI, 0.82 to 1.17). A renal event occurred in 4.3% in the dapagliflozin group and in 5.6% in the placebo group (hazard ratio, 0.76; 95% CI, 0.67 to 0.87), and death from any cause occurred in 6.2% and 6.6%, respectively (hazard ratio, 0.93; 95% CI, 0.82 to 1.04). Diabetic ketoacidosis was more common with dapagliflozin than with placebo (0.3% vs. 0.1%, P=0.02), as was the rate of genital infections that led to discontinuation of the regimen or that were considered to be serious adverse events (0.9% vs. 0.1%, P<0.001).In patients with type 2 diabetes who had or were at risk for atherosclerotic cardiovascular disease, treatment with dapagliflozin did not result in a higher or lower rate of MACE than placebo but did result in a lower rate of cardiovascular death or hospitalization for heart failure, a finding that reflects a lower rate of hospitalization for heart failure. (Funded by AstraZeneca; DECLARE-TIMI 58 ClinicalTrials.gov number, NCT01730534 .).
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| 24. |
- Zelissen, P M J, et al.
(author)
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Effect of three treatment schedules of recombinant methionyl human leptin on body weight in obese adults: a randomized, placebo-controlled trial.
- 2005
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In: Diabetes, obesity & metabolism. - : Wiley. - 1462-8902 .- 1463-1326. ; 7:6, s. 755-61
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Journal article (peer-reviewed)abstract
- AIM: The aim of this study was to evaluate the effect on body weight and safety of subcutaneously administered recombinant leptin in obese adults and to evaluate whether the timing of recombinant leptin administration influences efficacy. METHODS: A randomized, double-blind, placebo-controlled, multicentre study was designed, comprising of a 3-week dietary lead-in followed by a 12-week leptin or placebo treatment period. A total of 284 overweight and obese (body mass index 27-37.0 kg/m(2)) predominantly white (98%) women (66%) and men (34%) with a mean (+/-s.d.) 46.8+/-10.4 years of age were randomized into three treatment groups with three matching placebo groups. Recombinant leptin was administered by subcutaneous injection [10 mg/morning, 10 mg/evening or 20 mg/day (10 mg twice daily)]. Patients were counselled at baseline to reduce dietary intake by 2,100 kJ/day (500 kcal/day), and dietary advice was reinforced every 2-4 weeks. RESULTS: No statistically significant change in body weight occurred with recombinant leptin treatment compared with placebo treatment in any treatment group. No clinically significant adverse effects were observed with the exception of an increase in injection-site reactions in patients treated with recombinant leptin (83%) vs. placebo (36%). CONCLUSIONS: Administration of recombinant leptin to an overweight and obese population, in addition to a mildly energy-restricted diet, was not efficacious in terms of weight loss at the doses and schedules studied. The hypothesis that nocturnal administration of recombinant leptin might have a specific effect on weight loss was not supported.
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| 25. |
- Ahrén, Bo, et al.
(author)
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Semaglutide induces weight loss in subjects with type 2 diabetes regardless of baseline BMI or gastrointestinal adverse events in the SUSTAIN 1 to 5 trials
- 2018
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In: Diabetes, Obesity and Metabolism. - : Wiley. - 1462-8902. ; 20:9, s. 2210-2219
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Journal article (peer-reviewed)abstract
- Aims: To assess the effect of baseline body mass index (BMI) and the occurrence of nausea and/or vomiting on weight loss induced by semalgutide, a once-weekly glucagon-like peptide 1 analogue for the treatment of type 2 diabetes. Semaglutide demonstrated superior reductions in HbA1c and superior weight loss (by 2.3-6.3 kg) versus different comparators across the SUSTAIN 1 to 5 trials; the contributing factors to weight loss are not established. Materials and Methods: Subjects with inadequately controlled type 2 diabetes (drug-naïve or on background treatment) were randomized to subcutaneous semaglutide 0.5 mg (excluding SUSTAIN 3), 1.0 mg (all trials), or comparator (placebo, sitagliptin, exenatide extended release or insulin glargine). Subjects were subdivided by baseline BMI and reporting (yes/no) of any nausea and/or vomiting. Change from baseline in body weight was assessed within each trial and subgroup. A mediation analysis separated weight loss into direct or indirect (mediated by nausea or vomiting) effects. Results: Clinically relevant weight-loss differences were observed across all BMI subgroups, with a trend towards higher absolute weight loss with higher baseline BMI. Overall, 15.2% to 24.0% and 21.5% to 27.2% of subjects experienced nausea or vomiting with semaglutide 0.5 and 1.0 mg, respectively, versus 6.0% to 14.1% with comparators. Only 0.07 to 0.5 kg of the treatment difference between semaglutide and comparators was mediated by nausea or vomiting (indirect effects). Conclusions: In SUSTAIN 1 to 5, semaglutide-induced weight loss was consistently greater versus comparators, regardless of baseline BMI. The contribution of nausea or vomiting to this weight loss was minor.
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| 26. |
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| 27. |
- Clark, M. S., et al.
(author)
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Deciphering mollusc shell production: the roles of genetic mechanisms through to ecology, aquaculture and biomimetics
- 2020
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In: Biological Reviews. - : Wiley. - 1464-7931 .- 1469-185X. ; 95:6, s. 1812-37
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Journal article (peer-reviewed)abstract
- Most molluscs possess shells, constructed from a vast array of microstructures and architectures. The fully formed shell is composed of calcite or aragonite. These CaCO(3)crystals form complex biocomposites with proteins, which although typically less than 5% of total shell mass, play significant roles in determining shell microstructure. Despite much research effort, large knowledge gaps remain in how molluscs construct and maintain their shells, and how they produce such a great diversity of forms. Here we synthesize results on how shell shape, microstructure, composition and organic content vary among, and within, species in response to numerous biotic and abiotic factors. At the local level, temperature, food supply and predation cues significantly affect shell morphology, whilst salinity has a much stronger influence across latitudes. Moreover, we emphasize how advances in genomic technologies [e.g. restriction site-associated DNA sequencing (RAD-Seq) and epigenetics] allow detailed examinations of whether morphological changes result from phenotypic plasticity or genetic adaptation, or a combination of these. RAD-Seq has already identified single nucleotide polymorphisms associated with temperature and aquaculture practices, whilst epigenetic processes have been shown significantly to modify shell construction to local conditions in, for example, Antarctica and New Zealand. We also synthesize results on the costs of shell construction and explore how these affect energetic trade-offs in animal metabolism. The cellular costs are still debated, with CaCO(3)precipitation estimates ranging from 1-2 J/mg to 17-55 J/mg depending on experimental and environmental conditions. However, organic components are more expensive (similar to 29 J/mg) and recent data indicate transmembrane calcium ion transporters can involve considerable costs. This review emphasizes the role that molecular analyses have played in demonstrating multiple evolutionary origins of biomineralization genes. Although these are characterized by lineage-specific proteins and unique combinations of co-opted genes, a small set of protein domains have been identified as a conserved biomineralization tool box. We further highlight the use of sequence data sets in providing candidate genes forin situlocalization and protein function studies. The former has elucidated gene expression modularity in mantle tissue, improving understanding of the diversity of shell morphology synthesis. RNA interference (RNAi) and clustered regularly interspersed short palindromic repeats - CRISPR-associated protein 9 (CRISPR-Cas9) experiments have provided proof of concept for use in the functional investigation of mollusc gene sequences, showing for example that Pif (aragonite-binding) protein plays a significant role in structured nacre crystal growth and that theLsdia1gene sets shell chirality inLymnaea stagnalis. Much research has focused on the impacts of ocean acidification on molluscs. Initial studies were predominantly pessimistic for future molluscan biodiversity. However, more sophisticated experiments incorporating selective breeding and multiple generations are identifying subtle effects and that variability within mollusc genomes has potential for adaption to future conditions. Furthermore, we highlight recent historical studies based on museum collections that demonstrate a greater resilience of molluscs to climate change compared with experimental data. The future of mollusc research lies not solely with ecological investigations into biodiversity, and this review synthesizes knowledge across disciplines to understand biomineralization. It spans research ranging from evolution and development, through predictions of biodiversity prospects and future-proofing of aquaculture to identifying new biomimetic opportunities and societal benefits from recycling shell products.
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| 28. |
- Kos, K., et al.
(author)
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Regulation of the fibrosis and angiogenesis promoter SPARC/osteonectin in human adipose tissue by weight change, leptin, insulin, and glucose : Regulation of SPARC in human adipose tissue
- 2009
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In: Diabetes. - : American Diabetes Association. - 1939-327X .- 0012-1797. ; 58:8, s. 1780-8
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Journal article (peer-reviewed)abstract
- OBJECTIVE: Matricellular Secreted Protein, Acidic and Rich in Cysteine (SPARC), originally discovered in bone as osteonectin, is a mediator of collagen deposition and promotes fibrosis. Adipose tissue collagen has recently been found to be linked with metabolic dysregulation. Therefore, we tested the hypothesis that SPARC in human adipose tissue is influenced by glucose metabolism and adipokines. RESEARCH DESIGN AND METHODS: Serum and adipose tissue biopsies were obtained from morbidly obese nondiabetic subjects undergoing bariatric surgery and lean control subjects for analysis of metabolic markers, SPARC, and various cytokines (RT-PCR). Additionally, 24 obese subjects underwent a very-low-calorie diet of 1,883 kJ (450 kcal)/day for 16 weeks and serial subcutaneous-abdominal-adipose tissue (SCAT) biopsies (weight loss: 28 +/- 3.7 kg). Another six lean subjects underwent fast-food-based hyperalimentation for 4 weeks (weight gain: 7.2 +/- 1.6 kg). Finally, visceral adipose tissue explants were cultured with recombinant leptin, insulin, and glucose, and SPARC mRNA and protein expression determined by Western blot analyses. RESULTS: SPARC expression in human adipose tissue correlated with fat mass and was higher in SCAT. Weight loss induced by very-low-calorie diet lowered SPARC expression by 33% and increased by 30% in adipose tissue of subjects gaining weight after a fast-food diet. SPARC expression was correlated with leptin independent of fat mass and correlated with homeostasis model assessment-insulin resistance. In vitro experiments showed that leptin and insulin potently increased SPARC production dose dependently in visceral adipose tissue explants, while glucose decreased SPARC protein. CONCLUSIONS: Our data suggest that SPARC expression is predominant in subcutaneous fat and its expression and secretion in adipose tissue are influenced by fat mass, leptin, insulin, and glucose. The profibrotic effects of SPARC may contribute to metabolic dysregulation in obesity.
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