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Chronic liver disease is a major public health burden worldwide1. Although different aetiologies and mechanisms of liver injury exist, progression of chronic liver disease follows a common pathway of liver inflammation, injury and fibrosis2. Here we examined the association between clonal haematopoiesis of indeterminate potential (CHIP) and chronic liver disease in 214,563 individuals from 4 independent cohorts with whole-exome sequencing data (Framingham Heart Study, Atherosclerosis Risk in Communities Study, UK Biobank and Mass General Brigham Biobank). CHIP was associated with an increased risk of prevalent and incident chronic liver disease (odds ratio = 2.01, 95% confidence interval (95% CI) [1.46, 2.79]; P < 0.001). Individuals with CHIP were more likely to demonstrate liver inflammation and fibrosis detectable by magnetic resonance imaging compared to those without CHIP (odds ratio = 1.74, 95% CI [1.16, 2.60]; P = 0.007). To assess potential causality, Mendelian randomization analyses showed that genetic predisposition to CHIP was associated with a greater risk of chronic liver disease (odds ratio = 2.37, 95% CI [1.57, 3.6]; P < 0.001). In a dietary model of non-alcoholic steatohepatitis, mice transplanted with Tet2-deficient haematopoietic cells demonstrated more severe liver inflammation and fibrosis. These effects were mediated by the NLRP3 inflammasome and increased levels of expression of downstream inflammatory cytokines in Tet2-deficient macrophages. In summary, clonal haematopoiesis is associated with an elevated risk of liver inflammation and chronic liver disease progression through an aberrant inflammatory response.
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Hematopoiese Clonal , Suscetibilidade a Doenças , Hepatite , Cirrose Hepática , Animais , Camundongos , Hematopoiese Clonal/genética , Hepatite/genética , Inflamação/genética , Cirrose Hepática/genética , Hepatopatia Gordurosa não Alcoólica/genética , Razão de Chances , Progressão da DoençaRESUMO
Understanding the local chemical ordering propensity in random solid solutions, and tailoring its strength, can guide the design and discovery of complex, paradigm-shifting multicomponent alloys. First, we present a simple thermodynamic framework, based solely on binary enthalpies of mixing, to select optimal alloying elements to control the nature and extent of chemical ordering in high-entropy alloys (HEAs). Next, we couple high-resolution electron microscopy, atom probe tomography, hybrid Monte-Carlo, special quasirandom structures, and density functional theory calculations to demonstrate how controlled additions of Al and Ti and subsequent annealing drive chemical ordering in nearly random equiatomic face-centered cubic CoFeNi solid solution. We establish that short-range ordered domains, the precursors of long-range ordered precipitates, inform mechanical properties. Specifically, a progressively increasing local order boosts the tensile yield strengths of the parent CoFeNi alloy by a factor of four while also substantially improving ductility, which breaks the so-called strength-ductility paradox. Finally, we validate the generality of our approach by predicting and demonstrating that controlled additions of Al, which has large negative enthalpies of mixing with the constituent elements of another nearly random body-centered cubic refractory NbTaTi HEA, also introduces chemical ordering and enhances mechanical properties.
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BACKGROUND: Serum liver tests (serum tests) and histological assessment for T-cell mediated (TcM) rejection are essential for post-liver transplant monitoring. Liver biopsy carries risk of complications which are preferably avoided in low-risk patients. Multiparametric MRI (mpMRI) is a reliable non-invasive diagnostic method which quantifies liver disease activity and has prognostic utility. Our aim was to determine whether using mpMRI in combination with serum tests could noninvasively identify low-risk post-liver transplant patients who are eligible to avoid invasive liver biopsies. METHODS: In a multicentre prospective study (RADIcAL2), including 131 adult and paediatric (children and adolescent) patients with previous liver transplant from the Netherlands, Portugal, and UK, concomitant mpMRI and liver biopsies were performed. Biopsies were centrally read by two expert pathologists. TcM rejection was assessed using BANFF global assessment (BANFF-GA). Diagnostic accuracy to discriminate no rejection vs. indeterminate or TcM liver transplant rejection was performed using area under the receiver operating characteristic curve (AUC). RESULTS: In this study, 52% of patients received a routine (protocol) biopsy whilst 48% had a biopsy for suspicion of pathology. 38% of patients had no rejection, while 62% had either indeterminate (21%) or TcM rejection (41%). However, there was a high inter-observer variability (0
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BACKGROUND: Optimisation of the future liver remnant (FLR) is crucial to outcomes of extended liver resections. This study aimed to assess the quality of the FLR before and after dual vein embolization (DVE) by quantitative multiparametric MRI. METHODS: Of 100 patients with liver metastases recruited in a clinical trial (Precision1:NCT04597710), ten consecutive patients with insufficient FLR underwent quantitative multiparametric MRI pre- and post-DVE (right portal and hepatic vein). FLR volume, liver fibro-inflammation (corrected T1) scores and fat percentage (proton density fat fraction, PDFF) were determined. Patient metrics were compared by Wilcoxon signed-rank test and statistical analysis done using R software. RESULTS: All patients underwent uncomplicated DVE with improvement in liver remnant health, median 37 days after DVE: cT1 scores reduced from median (interquartile range) 790 ms (753-833 ms) to 741 ms (708-760 ms) p = 0.014 [healthy range <795 ms], as did PDFF from 11% (4-21%), to 3% (2-12%) p = 0.017 [healthy range <5.6%]. There was a significant increase in median (interquartile range) FLR volume from 33% (30-37%)% to 49% (44-52%), p = 0.002. CONCLUSION: This non-invasive and reproducible MRI technique showed improvement in volume and quality of the FLR after DVE. This is a significant advance in our understanding of how to prevent liver failure in patients undergoing major liver surgery.
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Embolização Terapêutica , Neoplasias Hepáticas , Imageamento por Ressonância Magnética Multiparamétrica , Valor Preditivo dos Testes , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hepatectomia , Veias Hepáticas/diagnóstico por imagem , Fígado/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/diagnóstico por imagem , Regeneração Hepática , Veia Porta/diagnóstico por imagem , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND & AIMS: Chronic liver disease (CLD) is associated with increased cardiovascular disease (CVD) risk. We investigated whether early signs of liver disease (measured by iron-corrected T1-mapping [cT1]) were associated with an increased risk of major CVD events. METHODS: Liver disease activity (cT1) and fat (proton density fat fraction [PDFF]) were measured using LiverMultiScan® between January 2016 and February 2020 in the UK Biobank imaging sub-study. Using multivariable Cox regression, we explored associations between liver cT1 (MRI) and primary CVD (coronary artery disease, atrial fibrillation [AF], embolism/vascular events, heart failure [HF] and stroke), and CVD hospitalisation and all-cause mortality. Liver blood biomarkers, general metabolism biomarkers, and demographics were also included. Subgroup analysis was conducted in those without metabolic syndrome (defined as at least three of: a large waist, high triglycerides, low high-density lipoprotein cholesterol, increased systolic blood pressure, or elevated haemoglobin A1c). RESULTS: A total of 33,616 participants (mean age 65 years, mean BMI 26 kg/m2, mean haemoglobin A1c 35 mmol/mol) had complete MRI liver data with linked clinical outcomes (median time to major CVD event onset: 1.4 years [range: 0.002-5.1]; follow-up: 2.5 years [range: 1.1-5.2]). Liver disease activity (cT1), but not liver fat (PDFF), was associated with higher risk of any major CVD event (hazard ratio 1.14; 95% CI 1.03-1.26; p = 0.008), AF (1.30; 1.12-1.51; p <0.001); HF (1.30; 1.09-1.56; p= 0.004); CVD hospitalisation (1.27; 1.18-1.37; p <0.001) and all-cause mortality (1.19; 1.02-1.38; p = 0.026). FIB-4 index was associated with HF (1.06; 1.01-1.10; p = 0.007). Risk of CVD hospitalisation was independently associated with cT1 in individuals without metabolic syndrome (1.26; 1.13-1.4; p <0.001). CONCLUSION: Liver disease activity, by cT1, was independently associated with a higher risk of incident CVD and all-cause mortality, independent of pre-existing metabolic syndrome, liver fibrosis or fat. IMPACT AND IMPLICATIONS: Chronic liver disease (CLD) is associated with a twofold greater incidence of cardiovascular disease. Our work shows that early liver disease on iron-corrected T1 mapping was associated with a higher risk of major cardiovascular disease (14%), cardiovascular disease hospitalisation (27%) and all-cause mortality (19%). These findings highlight the prognostic relevance of a comprehensive evaluation of liver health in populations at risk of CVD and/or CLD, even in the absence of clinical manifestations or metabolic syndrome, when there is an opportunity to modify/address risk factors and prevent disease progression. As such, they are relevant to patients, carers, clinicians, and policymakers.
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Doenças Cardiovasculares , Doenças do Sistema Digestório , Hepatopatias , Síndrome Metabólica , Humanos , Idoso , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Síndrome Metabólica/complicações , Síndrome Metabólica/epidemiologia , Bancos de Espécimes Biológicos , Hemoglobinas Glicadas , Biobanco do Reino Unido , Fatores de Risco , Hepatopatias/complicações , Biomarcadores , FerroRESUMO
BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is increasing in prevalence worldwide. NAFLD is associated with excess risk of all-cause mortality, and its progression to nonalcoholic steatohepatitis (NASH) and fibrosis accounts for a growing proportion of cirrhosis and hepatocellular cancer and thus is a leading cause of liver transplant worldwide. Noninvasive precise methods to identify patients with NASH and NASH with significant disease activity and fibrosis are crucial when the disease is still modifiable. The aim of this study was to examine the clinical utility of corrected T1 (cT1) vs magnetic resonance imaging (MRI) liver fat for identification of NASH participants with nonalcoholic fatty liver disease activity score ≥4 and fibrosis stage (F) ≥2 (high-risk NASH). METHODS: Data from five clinical studies (n = 543) with participants suspected of NAFLD were pooled or used for individual participant data meta-analysis. The diagnostic accuracy of the MRI biomarkers to stratify NASH patients was determined using the area under the receiver operating characteristic curve (AUROC). RESULTS: A stepwise increase in cT1 and MRI liver fat with increased NAFLD severity was shown, and cT1 was significantly higher in participants with high-risk NASH. The diagnostic accuracy (AUROC) of cT1 to identify patients with NASH was 0.78 (95% CI, 0.74-0.82), for liver fat was 0.78 (95% CI, 0.73-0.82), and when combined with MRI liver fat was 0.82 (95% CI, 0.78-0.85). The diagnostic accuracy of cT1 to identify patients with high-risk NASH was good (AUROC = 0.78; 95% CI, 0.74-0.82), was superior to MRI liver fat (AUROC = 0.69; 95% CI, 0.64-0.74), and was not substantially improved by combining it with MRI liver fat (AUROC = 0.79; 95% CI, 0.75-0.83). The meta-analysis showed similar performance to the pooled analysis for these biomarkers. CONCLUSIONS: This study shows that quantitative MRI-derived biomarkers cT1 and liver fat are suitable for identifying patients with NASH, and cT1 is a better noninvasive technology than liver fat to identify NASH patients at greatest risk of disease progression. Therefore, MRI cT1 and liver fat have important clinical utility to help guide the appropriate use of interventions in NAFLD and NASH clinical care pathways.
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Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico , Imageamento por Ressonância Magnética/métodos , Biomarcadores , Estudos Multicêntricos como AssuntoRESUMO
Refractory high-entropy alloys (RHEAs) are promising candidates for next-generation high-temperature materials. RHEAs containing Al, often exhibit a checkered pattern microstructure comprising a combination of disordered BCC and ordered B2 phases. Since the ordered B2 phase is based on the BCC parent matrix, distinguishing these two phases can be rather challenging. Advanced characterization techniques are necessary for a reliable qualitative and quantitative analysis of BCC and B2 phases in RHEAs. Additionally, there is a tendency for transformation of the ordered B2 phase into more complex ordered-omega type phases that are usually deleterious to mechanical properties. The current study focuses on the phase stability of a candidate RHEA, Al0.5Mo0.5NbTa0.5TiZr. Correlative transmission electron microscopy (TEM) and atom probe tomography (APT) have been employed to investigate the phase stability and transformation pathway of this RHEA when isothermally annealed at 800°C. The results show that a metastable two-phase BCC + B2 microstructure formed at the early stages of decomposition, eventually transforming into a three-phase BCC + B2 + hP18 microstructure. The hP18 phase is an ordered omega derivative of the ordered B2 phase. The correlative microscopy techniques (TEM and APT) reveal a very interesting interplay of compositional partitioning between the different phases and their respective stability.
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BACKGROUND & AIMS: A common genetic variant near MBOAT7 (rs641738C>T) has been previously associated with hepatic fat and advanced histology in 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 to characterise its role in the regulation of related metabolic phenotypes through a meta-analysis. METHODS: We performed a meta-analysis of studies with data on the association between rs641738C>T genotype and liver fat, NAFLD histology, and serum alanine aminotransferase (ALT), lipids or insulin. These included directly genotyped studies and population-level data from genome-wide association studies (GWAS). We performed a random effects meta-analysis using recessive, additive and dominant genetic models. RESULTS: 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 = 4.8×10-5) and diagnosis of NAFLD (odds ratio [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 = 1.5×10-4). rs641738C>T was not associated with fasting insulin and no effect was observed in children with NAFLD. CONCLUSIONS: Our study validates rs641738C>T near MBOAT7 as a risk factor for the presence and severity of NAFLD in individuals of European descent. LAY SUMMARY: Fatty liver disease is a common condition where fat builds up in the liver, which can cause liver inflammation and scarring (including 'cirrhosis'). It is closely linked to obesity and diabetes, but some genes are also thought to be important. We did this study to see whether one specific change ('variant') in one gene ('MBOAT7') was linked to fatty liver disease. We took data from over 40 published studies and found that this variant near MBOAT7 is linked to more severe fatty liver disease. This means that drugs designed to work on MBOAT7 could be useful for treating fatty liver disease.
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Aciltransferases/genética , Cirrose Hepática , Fígado/patologia , Proteínas de Membrana/genética , Hepatopatia Gordurosa não Alcoólica , Alanina Transaminase/sangue , Descoberta de Drogas , Predisposição Genética para Doença , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
NGM282, an engineered fibroblast growth factor 19 analogue, rapidly and significantly reduced liver fat content in a multicenter, randomized, double-blind, placebo-controlled study in patients with biopsy-confirmed nonalcoholic steatohepatitis (NASH). However, it is unclear whether these changes would be accompanied by histological improvement. In this open-label study, we assessed the histological efficacy of NGM282 in patients with biopsy-confirmed nonalcoholic steatohepatitis. Paired liver biopsies from 43 patients who received subcutaneous NGM282 (1 mg, n = 24; 3 mg, n = 19) once daily for 12 weeks were evaluated blinded to time point, subject, and clinical information. At week 12, NGM282 significantly reduced nonalcoholic fatty liver disease activity score (NAS; -1.9; 95% confidence interval, -2.6 to -1.2; P < 0.001 in the 1 mg group; -2.2, -3.1 to -1.3; P < 0.001 in the 3 mg group) and fibrosis (-0.5; -0.9 to 0; P = 0.035 in the 3 mg group) scores. Overall, 50% and 63% of the patients receiving NGM282 1 mg or 3 mg, respectively, improved NAS by 2 or more points without fibrosis worsening. Of the patients receiving NGM282 1 mg or 3 mg, 25% and 42%, respectively, improved liver fibrosis by one stage or more without worsening of steatohepatitis. Treatment with NGM282 led to relative reductions in liver fat content (-58% and -67% in the 1 mg and 3 mg groups, respectively), corrected T1 (cT1; -8% and -9%), alanine aminotransferase (ALT) (-67% and -60%), aspartate aminotransferase (-57% and -52%), and fibrogenesis biomarkers neoepitope-specific N-terminal propeptide of type III collagen (Pro-C3; -22% and -33%) and enhanced liver fibrosis score (ELF; -3% and -6%) at week 12. Greater reductions in Pro-C3, ELF, and cT1, but not in liver fat content, 7alpha-hydroxy-4-cholesten-3-one, or ALT, were observed in histological responders than in nonresponders. Conclusion: In this open-label study, NGM282 improved the histological features of NASH in 12 weeks with significant reductions in NAS and fibrosis scores, accompanied by improvements in noninvasive imaging and serum markers.
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Fatores de Crescimento de Fibroblastos/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/complicações , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Feminino , Fatores de Crescimento de Fibroblastos/administração & dosagem , Humanos , Injeções Subcutâneas , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Mastiha is a natural nutritional supplement with known anti-inflammatory properties. Non-alcoholic fatty liver disease (NAFLD) and Inflammatory bowel disease (IBD) are immune mediated inflammatory diseases that share common pathophysiological features. Mastiha has shown beneficial effects in both diseases. MicroRNAs have emerged as key regulators of inflammation and their modulation by phytochemicals have been extensively studied over the last years. Therefore, the aim of this study was to investigate whether a common route exists in the anti-inflammatory activity of Mastiha, specifically through the regulation of miRNA levels. Plasma miR-16, miR-21 and miR-155 were measured by Real-Time PCR before and after two double blinded and placebo-controlled randomized clinical trials with Mastiha. In IBD and particularly in ulcerative colitis patients in relapse, miR-155 increased in the placebo group (p = 0.054) whereas this increase was prevented by Mastiha. The mean changes were different in the two groups even after adjusting for age, sex and BMI (p = 0.024 for IBD and p = 0.042). Although the results were not so prominent in NAFLD, miR-155 displayed a downward trend in the placebo group (p = 0.054) whereas the levels did not changed significantly in the Mastiha group in patients with less advanced fibrosis. Our results propose a regulatory role for Mastiha in circulating levels of miR-155, a critical player in T helper-17 (Th17) differentiation and function.
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Anti-Inflamatórios/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Resina Mástique/uso terapêutico , MicroRNAs/sangue , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Adolescente , Adulto , Idoso , Anti-Inflamatórios/farmacologia , Método Duplo-Cego , Feminino , Humanos , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Masculino , Resina Mástique/farmacologia , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/imunologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Adulto JovemRESUMO
OBJECTIVES: Autoimmune hepatitis (AIH) is a progressive liver disease managed with corticosteroids and immunosuppression and monitored using a combination of liver biochemistry and histology. However, liver biopsy is invasive with risk of pain and bleeding. The aim of the present study was to investigate the utility of noninvasive imaging with multiparametric magnetic resonance imaging (MRI) (mpMRI) to provide clinically useful information on the presence and extent of hepatic inflammation, potentially guiding immunosuppression. METHODS: Eighty-one participants (aged 6-18), 21 healthy and 60 AIH patients, underwent multiparametric MRI to measure fibro-inflammation with iron-corrected T1 (cT1) at the Children's Memorial Health Institute in Warsaw alongside other clinical blood tests and liver biopsy at recruitment and after an average of 16-month follow-up (range 9-22 months). Correlation analyses were used to investigate the associations between cT1 with blood serum markers and histological scores. RESULTS: At recruitment, patients with AIH had a higher cT1 value than healthy controls (Pâ<â0.01). cT1 correlated significantly with key histopathological features of disease. Treatment naïve AIH patients showed evidence of inflammation and heterogeneity across the liver compared to healthy controls.At follow-up, cT1 showed utility in monitoring disease regression as most patients showed significantly reduced fibro-inflammation with treatment (Pâ<â0.0001) over the observational period. Six patients had histological fibrosis and clear fibro-inflammation on MR despite biochemical remission (normalized aspartate aminotransferase (AST), alanine aminotransferase (ALT), and immunoglobulin G [IgG]). CONCLUSIONS: Multiparametric MRI can measure disease burden in pediatric AIH and can show changes over time in response to therapy. Active disease can be seen even in biochemical remission in children.
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Hepatite Autoimune , Imageamento por Ressonância Magnética Multiparamétrica , Alanina Transaminase , Aspartato Aminotransferases , Criança , Hepatite Autoimune/diagnóstico por imagem , HumanosRESUMO
BACKGROUND & AIMS: MRI-based corrected T1 (cT1) is a non-invasive method to grade the severity of steatohepatitis and liver fibrosis. We aimed to identify genetic variants influencing liver cT1 and use genetics to understand mechanisms underlying liver fibroinflammatory disease and its link with other metabolic traits and diseases. METHODS: First, we performed a genome-wide association study (GWAS) in 14,440 Europeans, with liver cT1 measures, from the UK Biobank. Second, we explored the effects of the cT1 variants on liver blood tests, and a range of metabolic traits and diseases. Third, we used Mendelian randomisation to test the causal effects of 24 predominantly metabolic traits on liver cT1 measures. RESULTS: We identified 6 independent genetic variants associated with liver cT1 that reached the GWAS significance threshold (p <5×10-8). Four of the variants (rs759359281 in SLC30A10, rs13107325 in SLC39A8, rs58542926 in TM6SF2, rs738409 in PNPLA3) were also associated with elevated aminotransferases and had variable effects on liver fat and other metabolic traits. Insulin resistance, type 2 diabetes, non-alcoholic fatty liver and body mass index were causally associated with elevated cT1, whilst favourable adiposity (instrumented by variants associated with higher adiposity but lower risk of cardiometabolic disease and lower liver fat) was found to be protective. CONCLUSION: The association between 2 metal ion transporters and cT1 indicates an important new mechanism in steatohepatitis. Future studies are needed to determine whether interventions targeting the identified transporters might prevent liver disease in at-risk individuals. LAY SUMMARY: We estimated levels of liver inflammation and scarring based on magnetic resonance imaging of 14,440 UK Biobank participants. We performed a genetic study and identified variations in 6 genes associated with levels of liver inflammation and scarring. Participants with variations in 4 of these genes also had higher levels of markers of liver cell injury in blood samples, further validating their role in liver health. Two identified genes are involved in the transport of metal ions in our body. Further investigation of these variations may lead to better detection, assessment, and/or treatment of liver inflammation and scarring.
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Proteínas de Transporte de Cátions/genética , Fígado Gorduroso/genética , Cirrose Hepática/genética , Fígado , Síndrome Metabólica/genética , Europa (Continente)/epidemiologia , Fígado Gorduroso/epidemiologia , Feminino , Predisposição Genética para Doença , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/epidemiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Análise da Randomização Mendeliana , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Proteção , Medição de Risco/métodosRESUMO
BACKGROUND: Magnetic resonance cholangiopancreatography (MRCP) is an important tool for noninvasive imaging of biliary disease, however, its assessment is currently subjective, resulting in the need for objective biomarkers. PURPOSE: To investigate the accuracy, scan/rescan repeatability, and cross-scanner reproducibility of a novel quantitative MRCP tool on phantoms and in vivo. Additionally, to report normative ranges derived from the healthy cohort for duct measurements and tree-level summary metrics. STUDY TYPE: Prospective. PHANTOMS/SUBJECTS: Phantoms: two bespoke designs, one with varying tube-width, curvature, and orientation, and one exhibiting a complex structure based on a real biliary tree. Subjects Twenty healthy volunteers, 10 patients with biliary disease, and 10 with nonbiliary liver disease. SEQUENCE/FIELD STRENGTH: MRCP data were acquired using heavily T2 -weighted 3D multishot fast/turbo spin echo acquisitions at 1.5T and 3T. ASSESSMENT: Digital instances of the phantoms were synthesized with varying resolution and signal-to-noise ratio. Physical 3D-printed phantoms were scanned across six scanners (two field strengths for each of three manufacturers). Human subjects were imaged on four scanners (two fieldstrengths for each of two manufacturers). STATISTICAL TESTS: Bland-Altman analysis and repeatability coefficient (RC). RESULTS: Accuracy of the diameter measurement approximated the scanning resolution, with 95% limits of agreement (LoA) from -1.1 to 1.0 mm. Excellent phantom repeatability was observed, with LoA from -0.4 to 0.4 mm. Good reproducibility was observed across the six scanners for both phantoms, with a range of LoA from -1.1 to 0.5 mm. Inter- and intraobserver agreement was high. Quantitative MRCP detected strictures and dilatations in the phantom with 76.6% and 85.9% sensitivity and 100% specificity in both. Patients and healthy volunteers exhibited significant differences in metrics including common bile duct (CBD) maximum diameter (7.6 mm vs. 5.2 mm P = 0.002), and overall biliary tree volume 12.36 mL vs. 4.61 mL, P = 0.0026). DATA CONCLUSION: The results indicate that quantitative MRCP provides accurate, repeatable, and reproducible measurements capable of objectively assessing cholangiopathic change. Evidence Level: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;52:807-820.
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Colangiopancreatografia por Ressonância Magnética , Processamento de Imagem Assistida por Computador , Humanos , Imageamento por Ressonância Magnética , Imagens de Fantasmas , Estudos Prospectivos , Reprodutibilidade dos TestesRESUMO
BACKGROUND & AIMS: Liver cT1 , liver T1 , transient elastography (TE) and blood-based biomarkers have independently been shown to predict clinical outcomes but have not been directly compared in a single cohort of patients. Our aim was to compare these tests' prognostic value in a cohort of patients with compensated chronic liver disease. METHODS: Patients with unselected compensated liver disease aetiologies had baseline assessments and were followed up for development of clinical outcomes, blinded to the imaging results. The prognostic value of non-invasive liver tests at prespecified thresholds was assessed for a combined clinical endpoint comprising ascites, variceal bleeding, hepatic encephalopathy, hepatocellular carcinoma, liver transplantation and mortality. RESULTS: One hundred and ninety-seven patients (61% male) with median age of 54 years were followed up for 693 patient-years (median (IQR) 43 (26-58) months). The main diagnoses were NAFLD (41%), viral hepatitis (VH, 25%) and alcohol-related liver disease (ArLD; 14%). During follow-up 14 new clinical events, and 11 deaths occurred. Clinical outcomes were predicted by liver cT1 > 825ms with HR 9.9 (95% CI: 1.29-76.4, P = .007), TE > 8kPa with HR 7.8 (95% CI: 0.97-62.3, P = .02) and FIB-4 > 1.45 with HR 4.09 (95% CI: 0.90-18.4, P = .05). In analysis taking into account technical failure and unreliability, liver cT1 > 825 ms could predict clinical outcomes (P = .03), but TE > 8kPa could not (P = .4). CONCLUSIONS: We provide further evidence that liver cT1 , TE and serum-based biomarkers can predict clinical outcomes, but when taking into account technical failure/unreliability, TE cut-offs perform worse than those of cT1 and blood biomarkers.
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Técnicas de Imagem por Elasticidade , Varizes Esofágicas e Gástricas , Neoplasias Hepáticas , Imageamento por Ressonância Magnética Multiparamétrica , Biomarcadores , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/patologia , Feminino , Hemorragia Gastrointestinal/patologia , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , PrognósticoRESUMO
We study the two-dimensional assemblies of interacting colloidal particles in a loosely focussed optical trap. As the optical confinement is increased, the system becomes ordered and we investigate how these crystallites maintain their order under externally imposed oscillation. For small amplitudes, the crystalline order remains intact and the system behaves like a rigid body as predicted by numerical simulations. However, the rigidity breaks at large amplitudes, which we infer to be caused by the anharmonic component of the confinement potential. These studies are general enough to be applied to other physical systems comprising ordered finite-sized assemblies under external dynamic perturbation.
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Lamellar eutectic structure in Al0.7CoCrFeNi high-entropy alloy (HEA) is emerging as a promising candidate for structural applications because of its high strength-ductility combination. The alloy consists of a fine-scale lamellar fcc + B2 microstructure with high flow stresses > 1300 MPa under quasi-static tensile deformation and >10% ductility. The response to shear loading was not investigated so far. This is the first report on the shear deformation of a eutectic structured HEA and effect of precipitation on shear deformation. A split-Hopkinson pressure bar (SHPB) was used to compress the hat-shaped specimens to study the local dynamic shear response of the alloy. The change in the width of shear bands with respect to precipitation and deformation rates was studied. The precipitation of L12 phase did not delay the formation of adiabatic shear bands (ASB) or affect the ASB width significantly, however, the deformed region around ASB, consisting of high density of twins in fcc phase, was reduced from 80 µm to 20 µm in the stronger precipitation strengthened condition. We observe dynamic recrystallization of grains within ASBs and local mechanical response of individual eutectic lamellae before and after shear deformation and within the shear bands was examined using nano-indentation.
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BACKGROUND: The prevalence of metabolic syndrome (MetS) is increasing dramatically of late, across all ages irrespective of gender, socioeconomic status, and ethnicity. People with MetS have twice the likelihood of developing and dying from cardiovascular disease and more than seven times the risk of developing diabetes. OBJECTIVES: This study was undertaken to determine the prevalence of MetS among adults who were in their first three decades of adulthood and to find out the risk factors of MetS among them. METHODS: This was a community based cross-sectional study among 388 subjects aged 18-49 years selected by multistage random sampling in an area of Kolkata, India, from November 2016 to October 2018 over 2 years. Data collection was done using a structured questionnaire along with anthropometry, blood pressure measurement, and relevant blood tests. Physical activity was classified by the International Physical Activity Questionnaire Short-Form questionnaire. Data were analyzed using the Statistical Package for the Social Sciences (version 16.0), and descriptive statistics were calculated as frequency and percentage. Logistic regression was done to determine the strength of association between MetS and different risk factors. RESULTS: The prevalence of MetS was 44.6% (35.4% in males and 55.6% in females), and female gender, poor economic status, sedentary lifestyle, poor diet, and addiction of tobacco were found to be the risk factors of MetS in the final model using multivariable logistic regression. CONCLUSION: This research revealed the high prevalence of MetS in the community. The effective primordial and primary level of prevention along with prevailing secondary or tertiary level of prevention should have been employed to curtail the epidemic of MetS.
Assuntos
Síndrome Metabólica/epidemiologia , Adolescente , Adulto , Antropometria , Biomarcadores , Pressão Sanguínea , Estudos Transversais , Dieta , Exercício Físico , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Índia/epidemiologia , Estilo de Vida , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Sexuais , Fatores Socioeconômicos , Uso de Tabaco/epidemiologia , Adulto JovemAssuntos
Doenças Cardiovasculares , Sistema Cardiovascular , Hepatopatias , Humanos , Bancos de Espécimes Biológicos , Biobanco do Reino Unido , Hepatopatias/epidemiologia , Hepatopatias/etiologia , Reino Unido/epidemiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Análise da Randomização MendelianaRESUMO
BACKGROUND & AIMS: Excess liver iron content is common and is linked to the risk of hepatic and extrahepatic diseases. We aimed to identify genetic variants influencing liver iron content and use genetics to understand its link to other traits and diseases. METHODS: First, we performed a genome-wide association study (GWAS) in 8,289 individuals from UK Biobank, whose liver iron level had been quantified by magnetic resonance imaging, before validating our findings in an independent cohort (nâ¯=â¯1,513 from IMI DIRECT). Second, we used Mendelian randomisation to test the causal effects of 25 predominantly metabolic traits on liver iron content. Third, we tested phenome-wide associations between liver iron variants and 770 traits and disease outcomes. RESULTS: We identified 3 independent genetic variants (rs1800562 [C282Y] and rs1799945 [H63D] in HFE and rs855791 [V736A] in TMPRSS6) associated with liver iron content that reached the GWAS significance threshold (pâ¯<5â¯×â¯10-8). The 2 HFE variants account for â¼85% of all cases of hereditary haemochromatosis. Mendelian randomisation analysis provided evidence that higher central obesity plays a causal role in increased liver iron content. Phenome-wide association analysis demonstrated shared aetiopathogenic mechanisms for elevated liver iron, high blood pressure, cirrhosis, malignancies, neuropsychiatric and rheumatological conditions, while also highlighting inverse associations with anaemias, lipidaemias and ischaemic heart disease. CONCLUSION: Our study provides genetic evidence that mechanisms underlying higher liver iron content are likely systemic rather than organ specific, that higher central obesity is causally associated with higher liver iron, and that liver iron shares common aetiology with multiple metabolic and non-metabolic diseases. LAY SUMMARY: Excess liver iron content is common and is associated with liver diseases and metabolic diseases including diabetes, high blood pressure, and heart disease. We identified 3 genetic variants that are linked to an increased risk of developing higher liver iron content. We show that the same genetic variants are linked to higher risk of many diseases, but they may also be associated with some health advantages. Finally, we use genetic variants associated with waist-to-hip ratio as a tool to show that central obesity is causally associated with increased liver iron content.