| 1. |
- Feng, Shaohong, et al.
(författare)
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Dense sampling of bird diversity increases power of comparative genomics
- 2020
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 587:7833
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Tidskriftsartikel (refereegranskat)abstract
- Whole-genome sequencing projects are increasingly populating the tree of life and characterizing biodiversity(1-4). Sparse taxon sampling has previously been proposed to confound phylogenetic inference(5), and captures only a fraction of the genomic diversity. Here we report a substantial step towards the dense representation of avian phylogenetic and molecular diversity, by analysing 363 genomes from 92.4% of bird families-including 267 newly sequenced genomes produced for phase II of the Bird 10,000 Genomes (B10K) Project. We use this comparative genome dataset in combination with a pipeline that leverages a reference-free whole-genome alignment to identify orthologous regions in greater numbers than has previously been possible and to recognize genomic novelties in particular bird lineages. The densely sampled alignment provides a single-base-pair map of selection, has more than doubled the fraction of bases that are confidently predicted to be under conservation and reveals extensive patterns of weak selection in predominantly non-coding DNA. Our results demonstrate that increasing the diversity of genomes used in comparative studies can reveal more shared and lineage-specific variation, and improve the investigation of genomic characteristics. We anticipate that this genomic resource will offer new perspectives on evolutionary processes in cross-species comparative analyses and assist in efforts to conserve species. A dataset of the genomes of 363 species from the Bird 10,000 Genomes Project shows increased power to detect shared and lineage-specific variation, demonstrating the importance of phylogenetically diverse taxon sampling in whole-genome sequencing.
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| 2. |
- Fraley, Alexander E, et al.
(författare)
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Relationship of Oxidized Phospholipids and Biomarkers of Oxidized Low- Density Lipoprotein With Cardiovascular Risk Factors, Inflammatory Biomarkers, and Effect of Statin Therapy in Patients With Acute Coronary Syndromes Results From the MIRACL (Myocardial Ischemia Reduction With Aggressive Cholesterol Lowering) Trial
- 2009
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Ingår i: JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY. - : Elsevier BV. - 0735-1097. ; 53:23, s. 2186-2196
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Tidskriftsartikel (refereegranskat)abstract
- Objectives This study sought to define the relationship between oxidative biomarkers, cardiovascular disease (CVD) risk factors, and inflammatory and thrombosis biomarkers. Background Elevated levels of oxidized phospholipids (OxPL) on apolipoprotein B particles (apoB) represent a novel biomarker of CVD. Previous studies suggest that an increase in OxPL/apoB reflects a positive response to statins and a low-fat diet. Methods This study measured OxPL/apoB, lipoprotein (a) [Lp(a)], and oxidized low-density lipoprotein (OxLDL) biomarkers, consisting of immunoglobulin (Ig) G and IgM autoantibodies to malondialdehyde (MDA)-low-density lipoprotein (LDL) and IgG and IgM apoB-100 immune complexes (IC/apoB), at baseline and after 16 weeks of treatment with atorvastatin 80 mg/day or placebo in 2,342 patients with acute coronary syndromes (ACS) enrolled in the MIRACL (Myocardial Ischemia Reduction With Aggressive Cholesterol Lowering) trial. Results At baseline, potentially atheroprotective IgM autoantibodies and IgM IC/apoB were lower in male patients, diabetic patients, and patients andgt;65 years of age. Patients with an LDL level greater than the median (122 mg/dl) had higher levels of OxPL/apoB, Lp(a), and OxLDL biomarkers compared with those who had an LDL level less than the median. Atorvastatin resulted in significantly larger changes in all biomarkers in female patients, patients age andlt;65 years, patients with LDL cholesterol andlt;122 mg/dl, nonsmokers, and nondiabetic patients (p andlt; 0.0001 for all). In particular, a significant increase in OxPL/apoB in response to atorvastatin was noted in all 20 subgroups evaluated. Weak or no significant correlations were noted between all OxLDL biomarkers and C-reactive protein, serum amyloid A, tissue plasminogen activator, interleukin-6, intercellular adhesion molecule, vascular cell adhesion molecule, P-selectin, and E-selectin at randomization and 16 weeks. Conclusions In patients with ACS, baseline levels of oxidative biomarkers varied according to specific CVD risk factors and were largely independent of inflammatory biomarkers. Atorvastatin uniformly increased OxPL/apoB levels in all subgroups studied. Future studies are warranted to assess whether the increase in OxPL/apoB levels reflects the benefit of effective therapeutic interventions and prediction of new CVD events.
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| 3. |
- Kinlay, Scott, et al.
(författare)
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Endogenous tissue plasminogen activator and risk of recurrent cardiac events after an acute coronary syndrome in the MIRACL study
- 2009
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Ingår i: Atherosclerosis. - : Elsevier BV. - 0021-9150 .- 1879-1484. ; 206:2, s. 551-555
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To examine the relationship of baseline tissue plasminogen activator (t-PA) to early cardiovascular risk after an acute coronary syndrome, and the effect of intensive statin therapy. Methods: We measured plasma t-PA in 2860 of the 3086 (93%) subjects in the MIRACL study, an international randomized trial of atorvastatin 80mg daily versus placebo in patients with acute coronary syndromes. The relationship of t-PA to death, non-fatal acute myocardial infarction, cardiac arrest, or worsening angina over 16 weeks was assessed by Cox Proportional Hazards. D-dimer was measured in a random sample of 395 subjects. Results: Higher baseline t-PA was significantly related to the risk of recurrent events (HR = 1.25, p = 0.0014). This relationship was unaffected by adjustment for age, sex, troponin, hsCRP, and lipids (HR = 1.17, p = 0.029), but was attenuated by adjustment including body mass index and smoking (HR = 1.14, p = 0.08). D-dimer and t-PA concentrations were not related. Atorvastatin reduced the risk of recurrent events, but did not affect t-PA or D-dimer concentrations or the relationship of t-PA to outcomes. Conclusion: In patients with acute coronary syndromes, increasing t-PA concentration was related to a higher early risk of recurrent events, paradoxically reflecting impaired endogenous fibrinolysis. This relationship is due in part to the association of t-PA with age, body mass index and smoking. Although statins lower the risk of recurrent events after acute coronary syndromes, it is unlikely that this benefit is achieved through thrombolytic and fibrinolytic pathways. Published by Elsevier Ireland Ltd.
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| 4. |
- Zamani, Payman, et al.
(författare)
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Inflammatory Biomarkers, Death, and Recurrent Nonfatal Coronary Events After an Acute Coronary Syndrome in the MIRACL Study
- 2013
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Ingår i: Journal of the American Heart Association. - : WILEY-BLACKWELL, 111 RIVER ST, HOBOKEN 07030-5774, NJ USA. - 2047-9980. ; 2:1
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Tidskriftsartikel (refereegranskat)abstract
- Background-In acute coronary syndromes, C-reactive protein (CRP) strongly relates to subsequent death, but surprisingly not to recurrent myocardial infarction. Other biomarkers may reflect different processes related to these outcomes. We assessed 8 inflammatory and vascular biomarkers and the risk of death and recurrent nonfatal cardiovascular events in the 16 weeks after an acute coronary syndrome. less thanbrgreater than less thanbrgreater thanMethods and Results-We measured blood concentrations of CRP, serum amyloid A (SAA), interleukin-6 (IL-6), soluble intercellular adhesion molecule (ICAM), soluble vascular cell adhesion molecule (VCAM), E-selectin, P-selectin, and tissue plasminogen activator antigen (tPA) 24 to 96 hours after presentation with acute coronary syndrome in 2925 subjects participating in a multicenter study. Biomarkers were related to the risk of death, and recurrent nonfatal acute coronary syndromes (myocardial infarction or unstable angina) over 16 weeks using Cox proportional hazard models. On univariate analyses, baseline CRP (P=0.006), SAA (P=0.012), and IL-6 (Pandlt;0.001) were related to death, but not to recurrent nonfatal acute coronary syndromes. VCAM and tPA related to the risk of death (Pandlt;0.001, P=0.021, respectively) and to nonfatal acute coronary syndromes (P=0.021, P=0.049, respectively). Adjusting for significant covariates reduced the strength of the associations; however, CRP and SAA continued to relate to death. less thanbrgreater than less thanbrgreater thanConclusions-In acute coronary syndromes, the CRP inflammatory axis relates to the risk of death and may reflect myocardial injury. VCAM and tPA may have greater specificity for processes reflecting inflammation and thrombosis in the epicardial arteries, which determine recurrent coronary events.
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| 5. |
- Bhattacharya, Romit, et al.
(författare)
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Risk factors for clonal hematopoiesis of indeterminate potential in people with HIV : a report from the REPRIEVE trial
- 2024
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Ingår i: Blood Advances. - 2473-9529. ; 8:4, s. 959-967
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Tidskriftsartikel (refereegranskat)abstract
- Clonal hematopoiesis of indeterminate potential (CHIP), the clonal expansion of myeloid cells with leukemogenic mutations, results in increased coronary artery disease (CAD) risk. CHIP is more prevalent among people with HIV (PWH), but the risk factors are unknown. CHIP was identified among PWH in REPRIEVE (Randomized Trial to Prevent Vascular Events in HIV) using whole-exome sequencing. Logistic regression was used to associate sociodemographic factors and HIV-specific factors with CHIP adjusting for age, sex, and smoking status. In the studied global cohort of 4486 PWH, mean age was 49.9 (standard deviation [SD], 6.4) years; 1650 (36.8%) were female; and 3418 (76.2%) were non-White. CHIP was identified in 223 of 4486 (4.97%) and in 38 of 373 (10.2%) among those aged ≥60 years. Age (odds ratio [OR], 1.07; 95% confidence interval [CI], 1.05-1.09; P < .0001) and smoking (OR, 1.37; 95% CI, 1.14-1.66; P < .001) associated with increased odds of CHIP. Globally, participants outside of North America had lower odds of CHIP including sub- Saharan Africa (OR, 0.57; 95% CI, 0.4-0.81; P = .0019), South Asia (OR, 0.45; 95% CI, 0.23-0.80; P = .01), and Latin America/Caribbean (OR, 0.56; 95% CI, 0.34-0.87; P = .014). Hispanic/Latino ethnicity (OR, 0.38; 95% CI, 0.23-0.54; P = .002) associated with significantly lower odds of CHIP. Among HIV-specific factors, CD4 nadir <50 cells/mm3 associated with a 1.9-fold (95% CI, 1.21-3.05; P = .006) increased odds of CHIP, with the effect being significantly stronger among individuals with short duration of antiretroviral therapy (ART; OR, 4.15; 95% CI, 1.51-11.1; P = .005) (Pinteraction= .0492). Among PWH at low-to-moderate CAD risk on stable ART, smoking, CD4 nadir, North American origin, and non-Hispanic ethnicity associated with increased odds of CHIP.
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| 6. |
- Commins, Scott P, et al.
(författare)
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Galactose-α-1,3-galactose-specific IgE is associated with anaphylaxis but not asthma.
- 2012
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Ingår i: American journal of respiratory and critical care medicine. - 1535-4970 .- 1073-449X. ; 185:7, s. 723-30
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Tidskriftsartikel (refereegranskat)abstract
- IgE antibodies to the mammalian oligosaccharide galactose-α-1,3-galactose (α-gal) are common in the southeastern United States. These antibodies, which are induced by ectoparasitic ticks, can give rise to positive skin tests or serum assays with cat extract.
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| 7. |
- Dollery, Clare M., et al.
(författare)
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Neutrophil elastase in human atherosclerotic plaques : production by macrophages
- 2003
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Ingår i: Circulation. - : Lippincott Williams & Wilkins. - 0009-7322 .- 1524-4539. ; 107:22, s. 2829-2836
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Catabolism of the extracellular matrix (ECM) contributes to vascular remodeling in health and disease. Although metalloenzymes and cysteinyl proteinases have garnered much attention in this regard, the role of serine-dependent proteinases in vascular ECM degradation during atherogenesis remains unknown. We recently discovered the presence of the metalloproteinase MMP-8, traditionally associated only with neutrophils, in atheroma-related cells. Human neutrophil elastase (NE) plays a critical role in lung disease, but the paucity of neutrophils in the atheromatous plaque has led to neglect of its potential role in vascular biology. NE can digest elastin, fibrillar and nonfibrillar collagens, and other ECM components in addition to its ability to modify lipoproteins and modulate cytokine and MMP activity.METHODS AND RESULTS: Fibrous and atheromatous plaques but not normal arteries contained NE. In particular, NE abounded in the macrophage-rich shoulders of atheromatous plaques with histological features of vulnerability. Neutrophil elastase and macrophages colocalized in such vulnerable plaques (n=7). In situ hybridization revealed NE mRNA in macrophage-rich areas, indicating local production of this enzyme. Freshly isolated blood monocytes, monocyte-derived macrophages, and vascular endothelial cells in culture produced active NE and contained NE mRNA. Monocytes produced NE constitutively, with little regulation by cytokines IL-1beta, TNF-alpha, or IFN-gamma but released it when stimulated by CD40 ligand, a cytokine found in atheroma.CONCLUSIONS: These findings point to a novel role for the serine protease, neutrophil elastase, in matrix breakdown by macrophages, a critical process in adaptive remodeling of vessels and in the pathogenesis of arterial diseases.
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| 8. |
- Gumuser, Esra D., et al.
(författare)
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Clonal Hematopoiesis of Indeterminate Potential Predicts Adverse Outcomes in Patients With Atherosclerotic Cardiovascular Disease
- 2023
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Ingår i: Journal of the American College of Cardiology. - 0735-1097. ; 81:20, s. 1996-2009
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Tidskriftsartikel (refereegranskat)abstract
- Background: Clonal hematopoiesis of indeterminate potential (CHIP)—the age-related clonal expansion of blood stem cells with leukemia-associated mutations—is a novel cardiovascular risk factor. Whether CHIP remains prognostic in individuals with established atherosclerotic cardiovascular disease (ASCVD) is less clear. Objectives: This study tested whether CHIP predicts adverse outcomes in individuals with established ASCVD. Methods: Individuals aged 40 to 70 years from the UK Biobank with established ASCVD and available whole-exome sequences were analyzed. The primary outcome was a composite of ASCVD events and all-cause mortality. Associations of any CHIP (variant allele fraction ≥2%), large CHIP clones (variant allele fraction ≥10%), and the most commonly mutated driver genes (DNMT3A, TET2, ASXL1, JAK2, PPM1D/TP53 [DNA damage repair genes], and SF3B1/SRSF2/U2AF1 [spliceosome genes]) with incident outcomes were compared using unadjusted and multivariable-adjusted Cox regression. Results: Of 13,129 individuals (median age: 63 years) included, 665 (5.1%) had CHIP. Over a median follow-up of 10.8 years, any CHIP and large CHIP at baseline were associated with adjusted HRs of 1.23 (95% CI: 1.10-1.38; P < 0.001) and 1.34 (95% CI: 1.17-1.53; P < 0.001), respectively, for the primary outcome. TET2 and spliceosome CHIP, especially large clones, were most strongly associated with adverse outcomes (large TET2 CHIP: HR: 1.89; 95% CI: 1.40-2.55; P <0.001; large spliceosome CHIP: HR: 3.02; 95% CI: 1.95-4.70; P < 0.001). Conclusions: CHIP is independently associated with adverse outcomes in individuals with established ASCVD, with especially high risks observed in TET2 and SF3B1/SRSF2/U2AF1 CHIP.
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| 9. |
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| 10. |
- Isaksson, Hanna, et al.
(författare)
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The consequences of budding versus binary fission on adaptation and aging in primitive multicellularity
- 2021
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Ingår i: Genes. - : MDPI. - 2073-4425. ; 12:5
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Tidskriftsartikel (refereegranskat)abstract
- Early multicellular organisms must gain adaptations to outcompete their unicellular ancestors, as well as other multicellular lineages. The tempo and mode of multicellular adaptation is influenced by many factors including the traits of individual cells. We consider how a fundamental aspect of cells, whether they reproduce via binary fission or budding, can affect the rate of adaptation in primitive multicellularity. We use mathematical models to study the spread of beneficial, growth rate mutations in unicellular populations and populations of multicellular filaments reproducing via binary fission or budding. Comparing populations once they reach carrying capacity, we find that the spread of mutations in multicellular budding populations is qualitatively distinct from the other populations and in general slower. Since budding and binary fission distribute age-accumulated damage differently, we consider the effects of cellular senescence. When growth rate decreases with cell age, we find that beneficial mutations can spread significantly faster in a multicellular budding population than its corresponding unicellular population or a population reproducing via binary fission. Our results demonstrate that basic aspects of the cell cycle can give rise to different rates of adaptation in multicellular organisms.
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| 11. |
- Krettek, Alexandra, 1968-, et al.
(författare)
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Elastogenesis in human arterial disease : A role for macrophages in disordered elastin synthesis
- 2003
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Ingår i: Arteriosclerosis, Thrombosis and Vascular Biology. - : Lippincott Williams & Wilkins. - 1079-5642 .- 1524-4636. ; 23:4, s. 582-587
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Elastin, an extracellular matrix protein, constitutes about 30% of the dry weight of the arteries. Elastolysis induced by inflammatory processes is active in chronic arterial diseases. However, elastogenesis in arterial diseases has received little attention. In this work we hypothesized that disordered elastogenesis is active in matrix remodeling in atheroma and abdominal aortic aneurysm (AAA).METHODS AND RESULTS: Human AAA and atheroma have 4- to 6-fold more tropoelastin protein than nondiseased arteries. The smooth muscle cell-containing media and fibrous cap of atherosclerotic arteries contain ordered mature elastin, whereas macrophage (MPhi)-rich regions often have disorganized elastic fibers. Surprisingly, in addition to smooth muscle cells, MPhis in diseased arteries also produce the elastin precursor tropoelastin, as shown by double immunostaining, in situ hybridization, and reverse transcription-polymerase chain reaction for tropoelastin mRNA. Cultured monocyte-derived MPhis can express the elastin gene. AAA have 9-fold but atheroma only 1.6-fold lower levels of desmosine, a marker for mature cross-linked elastin, than normal arteries.CONCLUSIONS: This study demonstrates ongoing but often ineffective elastogenesis in arterial disease and establishes human macrophages as a novel source for this important matrix protein. These results have considerable import for understanding mechanisms of extracellular matrix remodeling in arterial diseases.
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| 12. |
- Krettek, Alexandra, 1968-, et al.
(författare)
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Enhanced expression of CD44 variants in human atheroma and abdominal aortic aneurysm : possible role for a feedback loop in endothelial cells
- 2004
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Ingår i: American Journal of Pathology. - : Elsevier. - 0002-9440 .- 1525-2191. ; 165:5, s. 1571-1581
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Tidskriftsartikel (refereegranskat)abstract
- CD44, a polymorphic hyaluronate receptor, may participate in chronic inflammation. We hypothesized that CD44 variants contribute to the development of arterial diseases. CD44 levels vary in normal and diseased arterial tissues in the following order: unaffected arteries < fibrous plaques < or = abdominal aortic aneurysm < atheromatous plaques; and correlate with macrophage content. Furthermore, plaque microvessels express CD44, and anti-CD44v3 or anti-CD44v6 treatment reduces endothelial cell proliferation but not apoptosis in vitro, suggesting functionality of these receptors. Endothelial cells express CD44H and CD44v6 after exposure to interleukin-1beta and tumor necrosis factor-alpha. Macrophages, a major source of abundant CD44 in vitro, express not only CD44H but also variants CD44v4/5, CD44v6, and CD44v7/8, isoforms distinctively regulated by proinflammatory cytokines. Several proinflammatory cytokines induce shedding of CD44 from the surface of macrophages and endothelial cells. Soluble CD44 stimulates the expression and release of interleukin-1beta from endothelial cells, suggesting a positive feedback loop of this cytokine. By demonstrating augmented expression of CD44 and variants within human atheroma and in abdominal aortic aneurysm as well as the vascular cell release of sCD44, a process regulated by proinflammatory cytokines, this study provides new insights on the functions of CD44 in arterial diseases.
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| 13. |
- Lannin, Natasha A., et al.
(författare)
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Public perspectives on acquired brain injury rehabilitation and components of care : A Citizens’ Jury
- 2021
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Ingår i: Health Expectations. - : John Wiley & Sons. - 1369-6513 .- 1369-7625. ; 24:2, s. 352-362
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Tidskriftsartikel (refereegranskat)abstract
- Background: Brain injury rehabilitation is an expensive and long-term endeavour. Very little published information or debate has underpinned policy for service delivery in Australia. Within the context of finite health budgets and the challenges associated with providing optimal care to persons with brain injuries, members of the public were asked ‘What considerations are important to include in a model of care of brain injury rehabilitation?’.Methods: Qualitative study using the Citizen Jury method of participatory research. Twelve adult jurors from the community and seven witnesses participated including a health services funding model expert, peak body representative with lived experience of brain injury, carer of a person with a brain injury, and brain injury rehabilitation specialists. Witnesses were cross-examined by jurors over two days.Results: Key themes related to the need for a model of rehabilitation to: be consumer-focused and supporting the retention of hope; be long-term; provide equitable access to services irrespective of funding source; be inclusive of family; provide advocacy; raise public awareness; and be delivered by experts in a suitable environment. A set of eight recommendations were made.Conclusion: Instigating the recommendations made requires careful consideration of the need for new models of care with flexible services; family involvement; recruitment and retention of highly skilled staff; and providing consumer-focused services that prepare individuals and their carers for the long term.Patient and public contribution: As jury members, the public deliberated information provided by expert witnesses (including a person with a head injury) and wrote the key recommendations.
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| 14. |
- Libby, Eric, et al.
(författare)
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Probabilistic models for predicting mutational routes to new adaptive phenotypes
- 2019
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Ingår i: Bio-protocol. - : Bio-Protocol, LLC. - 2331-8325. ; 9:20
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the translation of genetic variation to phenotypic variation is a fundamental problem in genetics and evolutionary biology. The introduction of new genetic variation through mutation can lead to new adaptive phenotypes, but the complexity of the genotype-to-phenotype map makes it challenging to predict the phenotypic effects of mutation. Metabolic models, in conjunction with flux balance analysis, have been used to predict evolutionary optimality. These methods however rely on large scale models of metabolism, describe a limited set of phenotypes, and assume that selection for growth rate is the prime evolutionary driver.Here we describe a method for computing the relative likelihood that mutational change will translate into a phenotypic change between two molecular pathways. The interactions of molecular components in the pathways are modeled with ordinary differential equations. Unknown parameters are offset by probability distributions that describe the concentrations of molecular components, the reaction rates for different molecular processes, and the effects of mutations. Finally, the likelihood that mutations in a pathway will yield phenotypic change is estimated with stochastic simulations.One advantage of this method is that only basic knowledge of the interaction network underlying a phenotype is required. However, it can also incorporate available information about concentrations and reaction rates as well as mutational biases and mutational robustness of molecular components. The method estimates the relative probabilities that different pathways produce phenotypic change, which can be combined with fitness models to predict evolutionary outcomes.
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| 15. |
- Lin, Amy Erica, et al.
(författare)
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Clonal Hematopoiesis of Indeterminate Potential With Loss of Tet2 Enhances Risk for Atrial Fibrillation Through Nlrp3 Inflammasome Activation
- 2024
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Ingår i: Circulation. - 0009-7322. ; 149:18, s. 1419-1434
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Clonal hematopoiesis of indeterminate potential (CHIP), a common age-associated phenomenon, associates with increased risk of both hematological malignancy and cardiovascular disease. Although CHIP is known to increase the risk of myocardial infarction and heart failure, the influence of CHIP in cardiac arrhythmias, such as atrial fibrillation (AF), is less explored. METHODS: CHIP prevalence was determined in the UK Biobank, and incident AF analysis was stratified by CHIP status and clone size using Cox proportional hazard models. Lethally irradiated mice were transplanted with hematopoietic-specific loss of Tet2, hematopoietic-specific loss of Tet2 and Nlrp3, or wild-type control and fed a Western diet, compounded with or without NLRP3 (NLR [NACHT, LRR {leucine rich repeat}] family pyrin domain containing protein 3) inhibitor, NP3-361, for 6 to 9 weeks. Mice underwent in vivo invasive electrophysiology studies and ex vivo optical mapping. Cardiomyocytes from Ldlr−/− mice with hematopoietic-specific loss of Tet2 or wild-type control and fed a Western diet were isolated to evaluate calcium signaling dynamics and analysis. Cocultures of pluripotent stem cell-derived atrial cardiomyocytes were incubated with Tet2deficient bone marrow-derived macrophages, wild-type control, or cytokines IL-1β (interleukin 1β) or IL-6 (interleukin 6). RESULTS: Analysis of the UK Biobank showed individuals with CHIP, in particular TET2 CHIP, have increased incident AF. Hematopoietic-specific inactivation of Tet2 increases AF propensity in atherogenic and nonatherogenic mouse models and is associated with increased Nlrp3 expression and CaMKII (Ca2+/calmodulin-dependent protein kinase II) activation, with AF susceptibility prevented by inactivation of Nlrp3. Cardiomyocytes isolated from Ldlr−/− mice with hematopoietic inactivation of Tet2 and fed a Western diet have impaired calcium release from the sarcoplasmic reticulum into the cytosol, contributing to atrial arrhythmogenesis. Abnormal sarcoplasmic reticulum calcium release was recapitulated in cocultures of cardiomyocytes with the addition of Tet2-deficient macrophages or cytokines IL-1β or IL-6. CONCLUSIONS: We identified a modest association between CHIP, particularly TET2 CHIP, and incident AF in the UK Biobank population. In a mouse model of AF resulting from hematopoietic-specific inactivation of Tet2, we propose altered calcium handling as an arrhythmogenic mechanism, dependent on Nlrp3 inflammasome activation. Our data are in keeping with previous studies of CHIP in cardiovascular disease, and further studies into the therapeutic potential of NLRP3 inhibition for individuals with TET2 CHIP may be warranted.
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| 16. |
- Lind, Peter A, et al.
(författare)
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Predicting mutational routes to new adaptive phenotypes
- 2019
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Ingår i: eLIFE. - : eLife Sciences Publications. - 2050-084X. ; 8, s. 1-31
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Tidskriftsartikel (refereegranskat)abstract
- Predicting evolutionary change poses numerous challenges. Here we take advantage of the model bacterium Pseudomonas fluorescens in which the genotype-to-phenotype map determining evolution of the adaptive ‘wrinkly spreader’ (WS) type is known. We present mathematical descriptions of three necessary regulatory pathways and use these to predict both the rate at which each mutational route is used and the expected mutational targets. To test predictions, mutation rates and targets were determined for each pathway. Unanticipated mutational hotspots caused experimental observations to depart from predictions but additional data led to refined models. A mismatch was observed between the spectra of WS-causing mutations obtained with and without selection due to low fitness of previously undetected WS-causing mutations. Our findings contribute toward the development of mechanistic models for forecasting evolution, highlight current limitations, and draw attention to challenges in predicting locus-specific mutational biases and fitness effects.
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| 17. |
- Ovchinnikova, Olga, et al.
(författare)
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T-Cell Activation Leads to Reduced Collagen Maturation in Atherosclerotic Plaques of Apoe−/− Mice
- 2009
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Ingår i: American Journal of Pathology. - : Elsevier. - 0002-9440 .- 1525-2191. ; 174:2, s. 693-700
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Tidskriftsartikel (refereegranskat)abstract
- Rupture of the collagenous, fibrous cap of an atherosclerotic plaque commonly causes thrombosis. Activated immune cells can secrete mediators that jeopardize the integrity of the fibrous cap. This study aimed to determine the relationship between T-cell-mediated inflammation and collagen turnover in a mouse model of experimental atherosclerosis. Both Apoe(-/-) x CD4dnT beta RII mice with defective transforming growth factor-beta receptors in T cells (and hence released from tonic suppression of T-cell activation) and lesion size-matched Apoe(-/-) mice were used. Picrosirius red staining showed a lower content of thick mature collagen fibers in lesions of Apoe(-/-) x CD4dnT beta RII mice, although both groups had similar levels of procollagen type I or M mRNA and total collagen content in lesions. Analysis of both gene expression and protein content showed a significant decrease of lysyl oxidase, the extracellular enzyme needed for collagen cross-linking, in aortas of Apoe(-/-) - CD4dnT beta RII mice. T-cell-driven inflammation provoked a selective and limited increase in the expression of proteinases that catabolize the extracellular matrix. Atheromata of Apoe(-/-) - CD4dnT beta RII mice had increased levels of matrix metalloproteinase-13 and cathepsin S mRNAs and of the active form of cathepsin S protein but no increase was detected in collagen fragmentation. our results suggest that exaggerated T-cell-driven inflammation limits collagen maturation in the atherosclerotic plaque while having little effect on collagen degradation.
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| 18. |
- Pentz, Jennifer T., et al.
(författare)
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Ecological Advantages and Evolutionary Limitations of Aggregative Multicellular Development
- 2020
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Ingår i: Current Biology. - : Cell Press. - 0960-9822 .- 1879-0445. ; 30:21, s. 4155-4164
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Tidskriftsartikel (refereegranskat)abstract
- All multicellular organisms develop through one of two basic routes: they either aggregate from free-living cells, creating potentially chimeric multicellular collectives, or they develop clonally via mother-daughter cellular adhesion. Although evolutionary theory makes clear predictions about trade-offs between these developmental modes, these have never been experimentally tested in otherwise genetically identical organisms. We engineered unicellular baker's yeast (Saccharomyces cerevisiae) to develop either clonally ("snowflake''; Dace2) or aggregatively ("floc''; GAL1p::FLO1) and examined their fitness in a fluctuating environment characterized by periods of growth and selection for rapid sedimentation. When cultured independently, aggregation was far superior to clonal development, providing a 35% advantage during growth and a 2.5-fold advantage during settling selection. Yet when competed directly, clonally developing snowflake yeast rapidly displaced aggregative floc. This was due to unexpected social exploitation: snowflake yeast, which do not produce adhesive FLO1, nonetheless become incorporated into flocs at a higher frequency than floc cells themselves. Populations of chimeric clusters settle much faster than floc alone, providing snowflake yeast with a fitness advantage during competition. Mathematical modeling suggests that such developmental cheating may be difficult to circumvent; hypothetical "choosy floc'' that avoid exploitation by maintaining clonality pay an ecological cost when rare, often leading to their extinction. Our results highlight the conflict at the heart of aggregative development: non-specific cellular binding provides a strong ecological advantage-the ability to quickly form groups-but this very feature leads to its exploitation.
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| 19. |
- Pentz, Jennifer T., et al.
(författare)
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Evolutionary consequences of nascent multicellular life cycles
- 2023
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Ingår i: eLIFE. - : eLife Sciences Publications Ltd. - 2050-084X. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- A key step in the evolutionary transition to multicellularity is the origin of multicellular groups as biological individuals capable of adaptation. Comparative work, supported by theory, suggests clonal development should facilitate this transition, although this hypothesis has never been tested in a single model system. We evolved 20 replicate populations of otherwise isogenic clonally reproducing 'snowflake' yeast (Δace2/∆ace2) and aggregative 'floc' yeast (GAL1p::FLO1 /GAL1p::FLO1) with daily selection for rapid growth in liquid media, which favors faster cell division, followed by selection for rapid sedimentation, which favors larger multicellular groups. While both genotypes adapted to this regime, growing faster and having higher survival during the group-selection phase, there was a stark difference in evolutionary dynamics. Aggregative floc yeast obtained nearly all their increased fitness from faster growth, not improved group survival; indicating that selection acted primarily at the level of cells. In contrast, clonal snowflake yeast mainly benefited from higher group-dependent fitness, indicating a shift in the level of Darwinian individuality from cells to groups. Through genome sequencing and mathematical modeling, we show that the genetic bottlenecks in a clonal life cycle also drive much higher rates of genetic drift-a result with complex implications for this evolutionary transition. Our results highlight the central role that early multicellular life cycles play in the process of multicellular adaptation.
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| 20. |
- Pineau, Rozenn M., et al.
(författare)
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Emergence and maintenance of stable coexistence during a long-term multicellular evolution experiment
- 2024
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Ingår i: Nature Ecology & Evolution. - : Nature Publishing Group. - 2397-334X. ; 8:5, s. 1010-1020
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Tidskriftsartikel (refereegranskat)abstract
- The evolution of multicellular life spurred evolutionary radiations, fundamentally changing many of Earth’s ecosystems. Yet little is known about how early steps in the evolution of multicellularity affect eco-evolutionary dynamics. Through long-term experimental evolution, we observed niche partitioning and the adaptive divergence of two specialized lineages from a single multicellular ancestor. Over 715 daily transfers, snowflake yeast were subjected to selection for rapid growth, followed by selection favouring larger group size. Small and large cluster-forming lineages evolved from a monomorphic ancestor, coexisting for over ~4,300 generations, specializing on divergent aspects of a trade-off between growth rate and survival. Through modelling and experimentation, we demonstrate that coexistence is maintained by a trade-off between organismal size and competitiveness for dissolved oxygen. Taken together, this work shows how the evolution of a new level of biological individuality can rapidly drive adaptive diversification and the expansion of a nascent multicellular niche, one of the most historically impactful emergent properties of this evolutionary transition.
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| 21. |
- Ridker, Paul M, et al.
(författare)
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Relationship of C-reactive protein reduction to cardiovascular event reduction following treatment with canakinumab: a secondary analysis from the CANTOS randomised controlled trial.
- 2018
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Ingår i: Lancet (London, England). - 1474-547X. ; 391:10118, s. 319-328
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Tidskriftsartikel (refereegranskat)abstract
- Canakinumab, a monoclonal antibody targeting interleukin-1β, reduces inflammation and cardiovascular event rates with no effect on lipid concentrations. However, it is uncertain which patient groups benefit the most from treatment and whether reductions in the inflammatory biomarker high-sensitivity C-reactive protein (hsCRP) correlate with clinical benefits for individual patients.The Canakinumab Anti-Inflammatory Thrombosis Outcomes Study (CANTOS) used computer-generated codes to randomly allocate 10061 men and women with a history of myocardial infarction to placebo or one of three doses of canakinumab (50 mg, 150 mg, or 300 mg) given subcutaneously once every 3 months. In a prespecified secondary analysis designed to address the relationship of hsCRP reduction to event reduction in CANTOS, we evaluated the effects of canakinumab on rates of major adverse cardiovascular events, cardiovascular mortality, and all-cause mortality according to on-treatment concentrations of hsCRP. We used multivariable modelling to adjust for baseline factors associated with achieved hsCRP and multiple sensitivity analyses to address the magnitude of residual confounding. The median follow-up was 3·7 years. The trial is registered with ClinicalTrials.gov, number NCT01327846.Baseline clinical characteristics did not define patient groups with greater or lesser cardiovascular benefits when treated with canakinumab. However, trial participants allocated to canakinumab who achieved hsCRP concentrations less than 2 mg/L had a 25% reduction in major adverse cardiovascular events (multivariable adjusted hazard ratio [HRadj]=0·75, 95% CI 0·66-0·85, p<0·0001), whereas no significant benefit was observed among those with on-treatment hsCRP concentrations of 2 mg/L or above (HRadj=0·90, 0·79-1·02, p=0·11). For those treated with canakinumab who achieved on-treatment hsCRP concentrations less than 2 mg/L, cardiovascular mortality (HRadj=0·69, 95% CI 0·56-0·85, p=0·0004) and all-cause mortality (HRadj=0·69, 0·58-0·81, p<0·0001) were both reduced by 31%, whereas no significant reduction in these endpoints was observed among those treated with canakinumab who achieved hsCRP concentrations of 2 mg/L or above. Similar differential effects were found in analyses of the trial prespecified secondary cardiovascular endpoint (which additionally included hospitalisation for unstable angina requiring unplanned revascularisation) and in sensitivity analyses alternatively based on median reductions in hsCRP, on 50% or greater reductions in hsCRP, on the median percent reduction in hsCRP, in dose-specific analyses, and in analyses using a causal inference approach to estimate the effect of treatment among individuals who would achieve a targeted hsCRP concentration.The magnitude of hsCRP reduction following a single dose of canakinumab might provide a simple clinical method to identify individuals most likely to accrue the largest benefit from continued treatment. These data further suggest that lower is better for inflammation reduction with canakinumab.Novartis Pharmaceuticals.
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| 22. |
- Saba, Luca, et al.
(författare)
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Carotid plaque-RADS : a novel stroke risk classification system
- 2024
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Ingår i: JACC Cardiovascular Imaging. - : Elsevier. - 1936-878X .- 1876-7591. ; 17:1, s. 62-75
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Tidskriftsartikel (refereegranskat)abstract
- Background: Carotid artery atherosclerosis is highly prevalent in the general population and is a well-established risk factor for acute ischemic stroke. Although the morphological characteristics of vulnerable plaques are well recognized, there is a lack of consensus in reporting and interpreting carotid plaque features.Objectives: The aim of this document is to establish a consistent and comprehensive approach for imaging and reporting carotid plaque by introducing the Plaque–Reporting and Data System (RADS) score.Methods: A panel of experts recognized the necessity to develop a classification system for carotid plaque and its defining characteristics. Using a multimodality analysis approach, the Plaque-RADS categories were established through consensus, drawing on existing published reports.Results: The authors present a universal classification that is applicable to both researchers and clinicians. The Plaque-RADS score offers a morphological assessment in addition to the prevailing quantitative parameter of “stenosis.” The Plaque-RADS score spans from grade 1 (indicating complete absence of plaque) to grade 4 (representing complicated plaque). Accompanying visual examples are included to facilitate a clear understanding of the Plaque-RADS categories.Conclusions: Plaque-RADS is a standardized and reliable system of reporting carotid plaque composition and morphology via different imaging modalities, such as ultrasound, computed tomography, and magnetic resonance imaging. This scoring system has the potential to help in the precise identification of patients who may benefit from exclusive medical intervention and those who require alternative treatments, thereby enhancing patient care. A standardized lexicon and structured reporting promise to enhance communication between radiologists, referring clinicians, and scientists.
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| 23. |
- Schuermans, Art, et al.
(författare)
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Clonal haematopoiesis of indeterminate potential predicts incident cardiac arrhythmias
- 2024
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Ingår i: European Heart Journal. - 0195-668X. ; 45:10, s. 791-805
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Tidskriftsartikel (refereegranskat)abstract
- Background and Clonal haematopoiesis of indeterminate potential (CHIP), the age-related expansion of blood cells with preleukemic mutaAims tions, is associated with atherosclerotic cardiovascular disease and heart failure. This study aimed to test the association of CHIP with new-onset arrhythmias.Methods UK Biobank participants without prevalent arrhythmias were included. Co-primary study outcomes were supraventricular arrhythmias, bradyarrhythmias, and ventricular arrhythmias. Secondary outcomes were cardiac arrest, atrial fibrillation, and any arrhythmia. Associations of any CHIP [variant allele fraction (VAF) ≥ 2%], large CHIP (VAF ≥10%), and gene-specific CHIP subtypes with incident arrhythmias were evaluated using multivariable-adjusted Cox regression. Associations of CHIP with myocardial interstitial fibrosis [T1 measured using cardiac magnetic resonance (CMR)] were also tested. Results This study included 410 702 participants [CHIP: n = 13 892 (3.4%); large CHIP: n = 9191 (2.2%)]. Any and large CHIP were associated with multi-variable-adjusted hazard ratios of 1.11 [95% confidence interval (CI) 1.04–1.18; P = .001] and 1.13 (95% CI 1.05–1.22; P = .001) for supraventricular arrhythmias, 1.09 (95% CI 1.01–1.19; P = .031) and 1.13 (95% CI 1.03–1.25; P = .011) for bradyarrhythmias, and 1.16 (95% CI, 1.00–1.34; P = .049) and 1.22 (95% CI 1.03–1.45; P = .021) for ventricular arrhythmias, respectively. Associations were independent of coronary artery disease and heart failure. Associations were also heterogeneous across arrhythmia subtypes and strongest for cardiac arrest. Gene-specific analyses revealed an increased risk of arrhythmias across driver genes other than DNMT3A. Large CHIP was associated with 1.31-fold odds (95% CI 1.07–1.59; P = .009) of being in the top quintile of myocardial fibrosis by CMR. Conclusions CHIP may represent a novel risk factor for incident arrhythmias, indicating a potential target for modulation towards arrhythmia prevention and treatment.
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| 24. |
- Shi, Guo-Ping, et al.
(författare)
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Cystatin C deficiency in human atherosclerosis and aortic aneurysms
- 1999
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Ingår i: Journal of Clinical Investigation. - 0021-9738. ; 104:9, s. 1191-1197
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Tidskriftsartikel (refereegranskat)abstract
- The pathogenesis of atherosclerosis and abdominal aortic aneurysm involves breakdown of the elastic laminae. Elastolytic cysteine proteases, including cathepsins S and K, are overexpressed at sites of arterial elastin damage, but whether endogenous local inhibitors counterbalance these proteases is unknown. We show here that, whereas cystatin C is normally expressed in vascular wall smooth muscle cells (SMCs), this cysteine protease inhibitor is severely reduced in both atherosclerotic and aneurysmal aortic lesions. Furthermore, increased abdominal aortic diameter among 122 patients screened by ultrasonography correlated inversely with serum cystatin C levels. In vitro, cytokine-stimulated vascular SMCs secrete cathepsins, whose elastolytic activity could be blocked when cystatin C secretion was induced by treatment with TGF-beta(1). The findings highlight a potentially important role for imbalance between cysteine proteases and cystatin C in arterial wall remodeling and establish that cystatin C deficiency occurs in vascular disease.
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| 25. |
- Smith, Hillary H., et al.
(författare)
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The grayness of the origin of life
- 2021
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Ingår i: Life. - : MDPI AG. - 2075-1729. ; 11:6
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Tidskriftsartikel (refereegranskat)abstract
- In the search for life beyond Earth, distinguishing the living from the non-living is paramount. However, this distinction is often elusive, as the origin of life is likely a stepwise evolutionary process, not a singular event. Regardless of the favored origin of life model, an inherent “grayness” blurs the theorized threshold defining life. Here, we explore the ambiguities between the biotic and the abiotic at the origin of life. The role of grayness extends into later transitions as well. By recognizing the limitations posed by grayness, life detection researchers will be better able to develop methods sensitive to prebiotic chemical systems and life with alternative biochemistries.
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